- Email: [email protected]
Influence of whole corn feeding on the performance, digestive tract development, and nutrient retention of geese1
Influence of whole corn feeding on the performance, digestive tract development, and nutrient retention of geese1 J. Lu,*2 X. L. Kong,*2 Z. Y. Wang,*†3 H. M. Yang,* K. N. Zhang,† and J. M. Zou‡ *College of Animal Science and Technology, Yangzhou University, 225009 Yangzhou, Jiangsu Province, P. R. China; †Jiangsu Engineering Research Center of Poultry Industry, 213000 Changzhou, Jiangsu Province, P. R. China; and ‡Poultry Institute, Chinese Academy of Agricultural Sciences, 225003 Yangzhou, Jiangsu Province, P. R. China ABSTRACT The objective of the current study was to investigate the influence of including whole corn (WC) in goose diets on the performance, digestive tract development, and nutrient retention. A total of 112 Yangzhou geese, 7 d old and with similar BW, were distributed into 8 pens of 14 birds/pen (7 male, 7 female). Each treatment was represented by 4 replicates. Geese were fed corn–soybean-based diets containing 640 g (8–28 d) and 615 g (29–70 d) of corn/kg of diet from 8 to 70 d of age, and 2 particle sizes of corn grains were used: ground corn (GC) and WC. During the period from 8 to 49 d, daily feed intake (P < 0.05) and daily weight gain (P = 0.054) of WC-fed birds tended to be lower than that of GC-fed birds. However, WC diet tended to improve (P = 0.07) G:F from 50 to 70 d of age. Higher relative weights of the gizzard (P < 0.05) at 28, 49, and 70 d, proventriculus at 49 d, and duodenum
at 28 and 70 d of age were observed in birds fed the WC diet compared with those fed the GC diet. Intestinal wall thickness in the jejunum and crypt depth and intestinal wall thickness in the ileum were greater (P < 0.05) in WC-fed birds at 28 d of age. Villus height and intestinal wall thickness in the duodenum and villus height in the jejunum were greater in birds fed the WC diet compared with those fed the GC diet at 70 d of age, and birds fed the WC diet had a greater (P < 0.05) intestinal wall thickness, villus height, and crypt depth measurements in the ileum compared with those fed the GC diet. The retention ratio of CP and neutral detergent fiber were higher (P < 0.05) in birds fed the WC diet than in those fed the GC diet. Overall, no negative effect was observed in birds fed the WC diet compared with those maintained on the GC diet.
Key words: goose, whole corn, performance, digestive tract development, nutrient retention ratio 2011 Poultry Science 90:587–594 doi:10.3382/ps.2010-01054
INTRODUCTION
ing will significantly lower the cost of feed manufacture (Reece et al., 1986; Amerah et al., 2009). Moreover, it addresses consumer requirements for a more natural feeding system and can further improve bird performance (Gabriel et al., 2003, 2007). Many researchers have indicated that inclusion of whole grain could improve the performance and stimulate the development of the gastrointestinal tract in broilers (Gabriel et al., 2003). Taylor and Jones (2004) found that prepelleting inclusion of 200 g/kg of whole wheat had no effect on broiler performance but increased relative gizzard weights. Similar results were reported by Svihus et al. (2004) with prepelleting inclusion of 500 g/kg of whole wheat. The gastrointestinal tract represents a functional link among ingestion, digestion, and absorption. Furthermore, digestive constraints may, in part, influence traits such as growth, reproduction, and survival (Naya et al., 2005). For example, a more developed gizzard may enhance the grinding of feed that will increase the exposure of nutrients to digestive
Cereal grains are generally ground before incorporation into poultry feed. However, the use of whole grains has been of interest to researchers in Northern European countries, in Australia, and in Canada, to reduce the feed costs caused by transport, handling, and processing (Gabriel et al., 2007; Amerah and Ravindran, 2008; Amerah et al., 2008, 2009). Because decreasing feed particles to a finer size requires greater energy, any reduction in energy consumption used for grind©2011 Poultry Science Association Inc. Received August 8, 2010. Accepted December 11, 2010. 1 This work was financially supported by Scientific and Technical Support Program of Jiangsu Province (BE2009351) and National Technology System of Waterfowl Industrial (nycytx-45-22), P. R. China. 2 These authors contributed equally to the work. 3 Corresponding author: [email protected], [email protected]
587
588
Lu et al.
enzymes and improve nutrient digestion (Hetland et al., 2002; Gabriel et al., 2003), energy utilization (Preston et al., 2000), and performance (Ravindran et al., 2006). A well-developed gizzard is associated with improvement in gut motility (Ferket, 2000) and may prevent pathogenic bacteria from entering the intestinal tract (Bjerrum et al., 2005), thus reducing the risk of coccidiosis and other enteric diseases (Engberg et al., 2004; Bjerrum et al., 2005). Recently, Ravindran et al. (2006) studied the effects of a low inclusion level of whole wheat (100 g/kg from 1 to 21 d and 200 g/kg from 22 to 35 d) on the development of digestive organs. Gabriel et al. (2007) studied the effects of feeding whole wheat (200 g/kg in starter diet, 300 g/kg in grower diet, and 400 g/kg in finisher diet) on the development of the digestive tract of broiler chickens. In the current study, geese were selected as experimental animals. With the development of animal husbandry in china, goose production is becoming specialized and more widespread, and there are approximately 204 million geese in China (FAO-STAT, 2008). Geese are herbivorous waterfowl and they consume and digest large amounts of green grass, clover, and some plants (Kropp, 1975). They are able to utilize a highfiber diet because they have an efficient and powerful proventriculus and gizzard and because of the effective microbial breakdown of fiber in the cecum and large intestine (Yang et al., 2009). Most research has been reported in broilers, and most of the grains used have been wheat. Data on the effect of whole grains on other poultry (for example, geese) are rare. Thus, the objective of the current study was to investigate the influence of including whole corn in diets on the performance, digestive tract development, and nutrient retention ratio of geese from 8 to 70 d of age.
MATERIALS AND METHODS Animal and Housing The experimental procedures were approved by the Yangzhou University Animal Care and Use Committee. A total of 112 Yangzhou geese, 7 d old and with similar BW, produced by the same flock of geese, were obtained from a commercial hatchery. These birds were distributed to 8 pens of 14 birds/pen (7 male, 7 female) according to similar pen weight. Each treatment was represented by 4 replicates (pens). The pens were equipped with drinkers and individual feeders. The birds were transferred to grower pens (4 m × 6 m; in the same room) at 29 d of age. The room temperature was maintained at 28°C for the first week of the experiment and was subsequently gradually reduced to 24°C by 21 d of age, after which no heat was provided. The birds received 20 h of constant lighting during the period from 8 to 28 d, after which the geese were under natural daylight. Body weights were recorded at 7, 28, 49, and
70 d of age and feed intake by pen was measured on a daily basis. Mortality was recorded as it occurred, and G:F values were corrected for the BW of any birds that died during the course of the experiment.
Diets All birds were provided corn–soybean-based diets, and 2 particle sizes of corn grain were used: ground corn (GC) and whole corn (WC). To create the GC, the WC was ground in a hammer mill to pass through a screen size of 2 mm. The diets (Table 1), containing GC or WC plus soybean meal, fish meal, and alfalfa meal, were formulated to meet or exceed NRC (1994) recommendations for major nutrients for geese. The diets differed only by the corn grain size. The diets, in mash form, were offered ad libitum to each replicate. Water was freely available throughout the trial.
Digestive Tract and Intestinal Morphology Measurements On d 28 and 70, 4 birds from each replicate (2 male, 2 female) with BW closest to the mean weight of the pen were killed by cervical dislocation. Two of these birds (1 male, 1 female) were used for measurements of the digestive tract and the other 2 birds (1 male, 1 female) were used for the microscopic study of intestinal morTable 1. Composition and calculated analysis (g/kg, as fed) of the experimental diets1 Item
8–28 d
29–70 d
Ingredient Corn Soybean meal Fish meal Alfalfa meal Soybean oil Calcium hydrogen phosphate Limestone Salt Vitamin and trace mineral premix2 Composition3 ME4 (MJ/kg) CP Crude fiber Calcium Available phosphorus NaCl Methionine Lysine
640 270 30 20 0 18 9 3 10 11.63 190.1 34.8 10.8 6.0 3.7 4.5 10.2
615 136 30 160 20 19 8 2 10 12.17 161.8 59.6 1.13 6.3 3.1 4.3 7.4
1Corn
was provided as either ground or whole. per kilogram of diet: vitamin A (retinyl acetate), 30 mg; vitamin D3 (cholecalciferol), 0.5625 mg; vitamin E (di-α-tocopheryl acetate), 150 mg; vitamin K (2-methyl-1,4-naphthoquinone), 100 mg; thiamin, 50 mg; riboflavin, 600 mg; pyridoxine, 100 mg; vitamin B12 (cobalamin), 1 mg; nicotinic acid, 3 g; pantothenic acid, 900 mg; folic acid, 50 mg; biotin, 4 mg; choline, 35 g; Fe, 6 g; Cu, 1 g; Mn, 9.5 g; Zn, 9 g; I, 50 mg; Se, 30 mg. 3Analyzed values given for CP, crude fiber, calcium, and available phosphorus. Calculated values given for NaCl, methionine, and lysine. 4The values are calculated from ingredient AME values for chickens. 2Supplied,
589
WHOLE CORN IN GOOSE DIETS
phology. On d 49, 2 birds were killed for measurements of the digestive tract. The live weight was measured on 7, 28, 49, and 70 d of age, and weights of digestive tract segments from the proventriculus to the ceca of each bird were determined. The length of each intestinal segment was determined with a flexible tape on a glass surface to prevent inadvertent stretching. The length (±0.01 cm) of the small intestine (from the pyloric junction to the ileocecal junction), the length of the duodenum (from the pyloric junction to the most distal point of insertion of the duodenal mesentery), the length of the jejunum (from the most distal point of insertion of the duodenal mesentery to the junction with Meckel’s diverticulum), the length of the ileum (from the junction with Meckel’s diverticulum to the ileocecal junction), and the length of cecum were determined. After division and freeing of each intestinal segment, separating all connective tissue, and fat and removing the content with ice-cold saline flushing, the empty weights (±0.01 g) and lengths of each segment were determined along with those of the proventriculus and the gizzard. The relative values were calculated as a ratio of live BW. For intestinal morphological examinations, sections from the middle of the duodenum, jejunum, and ileum (about 2 cm in length) were excised and flushed with ice-cold saline and immediately placed in Bouin’s fluid. Samples were transferred into 70% ethanol after 24 h. Each fixed sample was then embedded in wax and sectioned at a thickness of 7 µm, stained with alcian blue and hematoxylin-eosin, and examined by light microscopy. Six intestinal segments were fixed in each slide, and the slides were viewed on a Zeiss Axiophot microscope (Carl Zeiss, Oberkochen, Germany). Visual measurements of villus height, crypt depth, and intestinal wall thickness were made on 10 villi at 40× and 100× magnifications using imaging software (LYWN-HP Super CCD, Liyang, Chengdu, P. R. China). The variables measured were villus height (the distance from the apex of the villus to the junction of the villus and crypt), crypt depth (the distance from the junction to the basement membrane of the epithelial cell at the bottom of the crypt), and intestinal wall thickness.
Determination of Nutrient Retention Ratio Nutrient retention ratio was determined according to the procedure of Yang et al. (2009) and Shi et al. (2009). At 70 d of age, 4 male geese from each group (1 bird/ pen) with BW closest to the mean weight of the group were selected and housed separately in metabolism cages (75 cm × 65 cm × 35 cm) with wire floors, equipped with individual feeders and self-drinking systems, and the data were recorded individually. Housing temperature was maintained at 24°C. The birds were allowed ad libitum access to water and diet (29–70 d) for 10 d. The technique for geese (24 h for fasting + 24 h for excreta collection) advised by Shi et al. (2009) was used
in this experiment. After fasting for 24 h, all birds were tube fed 70 g of diet (29–70 d). After crop intubation, excreta were collected and dried to a constant weight at 65°C, after reaching equilibrium with the atmospheric moisture for 24 h, weighed, and ground to pass through a 40-mesh sieve. The excreta was immediately frozen and stored at −20°C for further analysis. Samples were analyzed for total N using the microKjeldahl method (990.03; AOAC, 2000). Crude protein was calculated as N × 6.25. Calcium was determined by atomic absorption spectrophotometry (927.02; AOAC, 2000). Phosphorus was determined photometrically as orthophosphate from filtered ash solutions using the vanado-molybdate method. Ashing of samples was performed at 550°C for 12 h. Crude fiber was measured by sequential extraction with diluted acid and alkali (962.09; AOAC, 2000). Neutral detergent fiber (NDF) and acid detergent fiber were determined sequentially as described by Van Soest et al. (1991) and expressed on an ash-free basis. The nutrient retention ratio was calculated using the following formula: nutrient retention ratio = (feed intake × nutrientdiet − excreta output × nutrientexcreta)/ (feed intake × nutrientdiet) × 100%.
Statistical Analysis Data were compared in a completely randomized design by the one-tailed t-test of SAS software (SAS Institute, 1996). Statements of significance were based on P < 0.05 unless otherwise stated.
RESULTS Bird Performance During the periods from 8 to 28 and 29 to 49 d of age, daily feed intake of WC-fed birds (P < 0.05) was lower than that of GC-fed birds (Table 2). However, no significant difference (P > 0.05) in daily feed intake was observed from 50 to 70 and 8 to 70 d of age. Daily weight gain tended to decrease (P = 0.054) in birds fed the WC diet from 8 to 28 d of age, whereas WC in diet had no effect (P > 0.05) on the daily weight gain from 29 to 49, 50 to 70, and 8 to 70 d of age. Birds fed the WC diet tended to have improved (P = 0.070) G:F from 50 to 70 d of age compared with that of birds maintained on GC diet, but no effect (P > 0.05) was found in other periods.
Digestive Tract Measurements The effects of WC feeding on the relative tissue weights of the various gastrointestinal components of geese are shown in Table 3. The relative weights of the
590
0.1423 0.1871 0.014 0.070 0.3151 0.2986 0.012 0.376 2GC
1Each
value represents the mean of 4 replicates (8–28 d, 14 birds/replicate; 29–49 d, 10 birds/replicate; 50–70 d, 8 birds/replicate). = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole).
0.4913 0.4915 0.007 0.985 170.03 162.75 3.233 0.163 222.49 214.26 8.658 0.527 196.49 186.44 1.436 0.003 91.10 87.56 0.803 0.021 46.02 46.30 1.245 0.881 31.36 40.19 3.166 0.096 44.73 43.03 0.504 0.054 GC WC SEM Significance
61.96 55.67 2.550 0.132
50–70 d 50–70 d 29–49 d 8–28 d
Daily feed intake (g/bird)
8–70 d 50–70 d 29–49 d 8–28 d
During the period from 8 to 28 d of age, birds fed the WC diet tended to reduce daily feed intake and daily weight gain, as has been reported in broilers with access to whole wheat from 8 to 15 d of age (Gabriel et al., 2007). However, no effect was found on G:F from 8 to 28 d. Daily feed intake of birds fed the WC diet from 29 to 49 d of age was reduced compared with that of birds fed the GC diet, whereas no significant differences in daily feed intake were observed from 50 to 70 and 8 to 70 d of age. The birds were introduced to the WC diet at 7 d of age and had difficulties swallowing the WC diet during the first few days of life, as observed in broilers (Ravindran et al., 2006). Birds fed the WC diet improved G:F from 50 to 70 d of age, but
Treatment2
DISCUSSION
Daily weight gain (g/bird)
The retention ratios of CP, calcium, phosphorus, and fiber species are presented in Table 6. No significant difference (P > 0.05) was found in the retention ratios of calcium and phosphorus between WC-fed birds and GC-fed birds. However, the retention ratio of CP was generally higher (P < 0.05) in birds fed the WC diet. In addition, birds fed the GC diet improved (P < 0.05) the retention ratio of NDF, whereas no effect was found on the retention ratio of acid detergent fiber.
Table 2. Influence of whole corn feeding on the daily weight gain (g), daily feed intake (g), and G:F of geese1
Nutrient Retention Ratio
8–70 d
Intestinal Morphology Histological measurements of the villus, crypts, and intestinal wall were performed at 28 and 70 d of age (Table 5). At 28 d of age, the intestinal wall thickness in the jejunum, crypt depth, and intestinal wall thickness in the ileum were generally shorter (P < 0.05) in birds fed the GC diet compared with those fed the WC diet. At 70 d of age, villus height and intestinal wall thickness in the duodenum and villus height in the jejunum were greater (P < 0.05) in birds fed the WC diet, and birds fed the WC diet had greater (P < 0.05) villus height, crypt depth, and intestinal wall thickness measurements in the ileum compared with those fed the GC diet.
29–49 d 8–28 d
G:F (g/g)
8–70 d
gizzard and duodenum of WC-fed birds were greater (P < 0.05) than those of GC-fed birds at 28 d of age, but the relative weights of the jejunum, ileum, and ceca were not changed (P > 0.05). Similar results were found at 70 d of age; a diet effect was observed in the relative weights of the gizzard and duodenum, with a lower value (P < 0.05) in GC-fed birds. Higher relative weights of the proventriculus and gizzard were observed (P < 0.05) in birds fed the WC diet at 49 d of age, although no significant effect (P > 0.05) was found on the wet tissue weight of gut components. Relative lengths of various intestinal segments of geese at 28, 49, and 70 d of age are shown in Table 4. However, no effect (P > 0.05) was found on the relative length.
0.2708 0.2846 0.007 0.229
Lu et al.
591
WHOLE CORN IN GOOSE DIETS Table 3. Influence of whole corn feeding on the relative weights of gastrointestinal tract (g/kg) of geese at 28, 49, and 70 d of age1,2 Time and treatment3 28 d GC WC SEM Significance 49 d GC WC SEM Significance 70 d GC WC SEM Significance
Proventriculus
Gizzard
Duodenum
Jejunum
Ileum
Cecum
6.12 6.25 0.186 0.608 5.37 7.44 0.459 0.018 3.68 3.49 0.326 0.698
52.13 57.28 0.430 <0.001 34.28 40.13 1.334 0.021 36.36 43.45 1.714 0.026
6.46 7.65 0.281 0.024 4.62 5.33 0.252 0.094 2.46 3.28 0.232 0.046
15.71 15.72 0.248 0.978 11.55 11.34 0.983 0.886 6.02 6.66 0.540 0.434
14.97 15.39 0.453 0.536 9.65 8.87 0.582 0.380 6.61 4.66 0.841 0.151
2.92 3.05 0.145 0.563 2.90 2.87 0.196 0.920 1.54 2.52 0.765 0.400
1Each
value represents the mean of 4 replicates of 2 geese each. gizzard, duodenum, jejunum, ileum, and cecum values calculated as a ratio of live BW. 3GC = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole). 2Proventriculus,
no effect was found in other periods. In brief, results in this study are in agreement with those of studies using whole wheat instead of ground wheat from the second or third week of life, leading to no or positive effects on performance and feed efficiency during the overall rearing period (Preston et al., 2000; Hetland et al., 2002; Gabriel et al., 2003, 2007; Engberg et al., 2004; Svihus et al., 2004). Most studies were reported in broilers and focused on feed particle size. Provision of 200 g of whole wheat/kg in a mixed feeding system had no effect on the weight gain and feed efficiency in broilers (Amerah and Ravindran, 2008). Amerah et al. (2008) found that corn ground through a hammer mill screen opening of 7 mm, which resulted in coarse particles [geometric mean diameter (GMD): 0.528 mm], significantly decreased 21-d BW and increased F:G compared with corn ground through a screen opening of 1 mm (GMD: 0.297 mm). Particle
size influenced both BW and F:G, with coarse grinding (GMD: 1.20 mm) decreasing BW at 21 d and increasing F:G in corn-based diets (Lott et al., 1992). Kilburn and Edwards (2001) also found improvement in F:G and true ME when the diet included medium ground corn (GMD: 0.87 mm) compared with that made from coarse corn (GMD: 2.90 mm). Reece et al. (1986), however, found that the corn particle size (GMD: 0.68 vs. 1.29 mm) had no effect on performance when crumbled or pelleted diets were offered. The results of the current study suggest that WC diet had no negative effect on bird performance. Feeding the WC diet led to modifications of the upper part of the digestive tract (proventriculus, gizzard, duodenum). However, different results of the proventriculus are found in wheat-fed broilers, with a dilation of the proventriculus in birds fed ground wheat compared with those fed whole wheat (Gabriel et al.,
Table 4. Influence of whole corn feeding on the relative lengths of gastrointestinal tract (cm/kg) of geese at 28, 49, and 70 d of age1,2 Time and treatment3 28 d GC WC SEM Significance 49 d GC WC SEM Significance 70 d GC WC SEM Significance 1Each
Small intestine
Duodenum
Jejunum
Ileum
Cecum
145.95 148.27 2.983 0.603 83.71 84.43 4.849 0.920 62.16 60.87 2.213 0.693
25.55 28.00 0.869 0.092 13.15 14.39 0.375 0.058 10.38 11.48 0.451 0.136
61.00 63.11 0.914 0.152 33.44 34.54 2.186 0.735 25.10 25.93 1.229 0.648
59.41 57.15 1.855 0.422 30.51 31.57 1.180 0.547 23.86 22.68 1.138 0.491
16.25 15.53 0.707 0.497 9.21 9.69 0.603 0.604 13.91 12.78 0.821 0.368
value represents the mean of 4 replicates of 2 geese each. intestine, duodenum, jejunum, ileum, and cecum values calculated as a ratio of live BW. Small intestine = duodenum + jejunum + ileum. 3GC = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole). 2Small
592
Lu et al.
Table 5. Influence of whole corn feeding on villus height, crypt depth, and intestinal wall thickness (μm) of geese at 28 and 70 d of age1 Duodenum Time and treatment2 28 d GC2 WC3 SEM Significance 70 d GC2 WC3 SEM Significance
Jejunum
Ileum
Villus height
Crypt depth
Intestinal wall thickness
Villus height
Crypt depth
Intestinal wall thickness
Villus height
Crypt depth
Intestinal wall thickness
656.35 547.85 35.381 0.073 786.56 1,127.71 28.935 <0.001
134.61 152.44 13.853 0.398 114.62 119.94 4.631 0.448
187.34 187.27 18.195 0.998 271.17 320.31 12.404 0.031
801.79 735.86 57.193 0.446 723.48 1,059.27 18.753 <0.001
100.47 134.60 11.343 0.077 108.36 119.39 3.408 0.062
161.13 221.65 16.282 0.039 258.61 263.10 5.027 0.550
575.60 578.98 26.350 0.931 657.60 744.66 15.158 0.007
75.50 113.67 9.489 0.029 89.28 120.40 3.893 0.001
168.31 273.50 16.431 0.004 261.93 304.77 9.671 0.020
1Each 2GC
value represents the mean of 4 replicates of 2 geese each. = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole).
2003). The present data showed that the relative weight of the gizzard was greater in birds fed the WC diet. Similar findings have been reported with the use of whole grains in several studies (Engberg et al., 2004; Gabriel et al., 2007) and were attributed to the increased frequency of contraction of this organ (Roche, 1981) to reduce whole grains to fine particles. Promotion of gizzard development by whole grain is a strategy that has been found to prevent potentially pathogenic bacteria from entering the intestinal tract (Engberg et al., 2004). Moreover, the stronger mechanical development of the gizzard leads to smaller particle size of digesta in the intestine, which may increase digestion of all dietary compounds as observed for starch (Svihus and Hetland, 2001). However, the WC feeding in the current study had no effect on the relative length of the different intestinal segments. The effect of WC feeding was observed only in the relative weight of the duodenum, with a greater value for whole grains at 28 and 70 d of age, which is contrary to many reports: a lower weight of the duodenum was reported with whole wheat (Gabriel et al., 2003) and with a coarse particle diet compared with a fine particle diet (Nir et al., 1994). Other researches showed no modification of relative size of intestinal segments with substitution of ground wheat with whole wheat (Engberg et al., 2004; Ravindran et al., 2006). This can be explained that ef-
fects on the modification of digestive tract depend on grain type as reported by Amerah et al. (2008), who found that birds fed corn-based diets had a relatively heavier gizzard than those fed wheat-based diets. Intestinal wall thickness in the jejunum, crypt depth, and intestinal wall thickness in the ileum were greater in WC-fed birds at 28 d of age. Moreover, WC feeding had positive effects in the 3 segments of the small intestine at 70 d of age. Similar findings have been reported by Amerah and Ravindran (2008), who found that birds fed pelleted diets had a greater mucosal extent, villus height, and crypt depth measurements compared with those fed mash diets. However, the effect of feeding whole wheat was observed only in the duodenum (Gabriel et al., 2007), with crypt depth significantly decreased. The increased crypt depth in the current study was observed just in the ileum, which may be attributed to an increase in some bacterial populations, as observed in feeding whole wheat (Engberg et al., 2004). This may be related to an increased secretory activity such as a lower mucus production, goblet cells being particularly concentrated in the crypts (Langhout et al., 1999), and may also be related to an increase in cell turnover as shown by relationship between crypt depth and cell proliferation (Hedemann et al., 2003). Increased villus height and unchanged crypt depth in the duodenum and jejunum might indicate a general
Table 6. Influence of whole corn feeding on the retention ratio of CP, calcium, phosphorus, and fiber species1 (%) Treatment2
CP
Calcium
Phosphorus
NDF3
ADF4
GC WC SEM Significance
62.61 67.07 0.549 0.001
47.77 49.12 1.229 0.465
47.07 49.08 2.953 0.649
29.28 35.53 1.149 0.009
40.74 42.10 0.611 0.167
1Each
value represents the mean of 4 replicates of 1 bird each. = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole). 3NDF = neutral detergent fiber. 4ADF = acid detergent fiber. 2GC
WHOLE CORN IN GOOSE DIETS
increase in the digestive and absorptive capacity of the proximal small intestine in response to the greater flow of nutrients. It also showed that the intestinal structure was more oriented to digestion, with improved absorptive and hydrolysis potential, than to nutrient requirement for intestinal maintenance. In the current study, the nutrient retention ratio of CP and NDF were higher in birds fed the WC diet than in those fed the GC diet. Similar findings in starch digestibility were reported with inclusion of wood shavings (Amerah et al., 2009), coarse insoluble fiber (Hetland et al., 2003), and whole wheat (Svihus and Hetland, 2001; Hetland et al., 2002; Svihus et al., 2004). The results of the present study can probably be explained by the larger gizzard sizes and increased villus height observed in birds given the WC diet. A large, well-developed gizzard improves gut motility (Ferket, 2000) and may increase cholecystokinin release (Svihus et al., 2004), which in turn stimulates the secretion of pancreatic enzymes and gastroduodenal reflux (Duke, 1992). Hetland et al. (2003) reported that the total amount of bile acids in the gizzard increased in layers with access to wood shavings, indicating increased gastroduodenal reflux. On the other hand, a well-developed gizzard functions as a regulator of feed intake and improves nutrient retention. The findings of the current study support this thesis and it appears that WC in goose diets will have beneficial effects on digestive tract development and improve the nutrient retention ratio of CP and NDF. In summary, the data showed that daily weight gain of birds fed the WC diet was lower than that of birds fed the GC diet from 8 to 28 d of age, but feeding WC did not affect daily weight gain from 8 to 70 d of age. Higher relative weights of the gizzard at 28, 49, and 70 d of age, proventriculus at 49 d of age, and duodenum at 28 and 70 d of age were observed in birds fed WC diet compared with those fed the GC diet. Compared with birds fed the GC diet, villus height and intestinal wall thickness in the duodenum and villus height in the jejunum were greater in birds fed the WC diet at 70 d of age, and greater villus height, crypt depth, and intestinal wall thickness were found in the ileum. Moreover, birds fed the WC diet had improved retention ratio of CP and NDF. Thus, heavier gizzards, increased villus height, and the positive results on the retention ratio seemed sufficient to allow using WC in goose diet.
ACKNOWLEDGMENTS This work was financially supported by Scientific and Technical Support Program of Jiangsu Province (BE2009351), and National Technology System of Waterfowl Industrial (nycytx-45-22), P. R. China.
REFERENCES Amerah, A. M., and V. Ravindran. 2008. Influence of method of whole-wheat feeding on the performance, digestive tract devel-
593
opment and carcass traits of broiler chickens. Anim. Feed Sci. Technol. 147:326–339. Amerah, A. M., V. Ravindran, and R. G. Lentle. 2009. Influence of insoluble fibre and whole wheat inclusion on the performance, digestive tract development and ileal microbiota profile of broiler chickens. Br. Poult. Sci. 50:366–375. Amerah, A. M., V. Ravindran, R. G. Lentle, and D. G. Thomas. 2008. Influence of feed particle size on the performance, energy utilization, digestive tract development, and digesta parameters of broiler starters fed wheat- and corn-based diets. Poult. Sci. 87:2320–2328. AOAC. 2000. Official Methods of Analysis. 17th ed. Association of Official Analytical Chemists, Gaithersburg, MD. Bjerrum, L., K. Pedersen, and R. M. Engberg. 2005. The influence of whole wheat feeding on Salmonella infection and gut flora composition in broilers. Avian Dis. 49:9–15. Duke, G. E. 1992. Recent studies on regulation of gastric motility in turkeys. Poult. Sci. 71:1–8. Engberg, R. M., M. S. Hedemann, S. Steenfeldt, and B. B. Jensen. 2004. Influence of whole wheat and xylanase on broiler performance and microbial composition and activity in the digestive tract. Poult. Sci. 83:925–938. FAO-STAT. 2008. Food and Agriculture Organization of the United Nations. http://faostat.fao.org/site/573/default.aspx#ancor Ferket, P. 2000. Feeding whole grains to poultry improves gut health. Feedstuffs 72:12–14. Gabriel, I., S. Mallet, and M. Leconte. 2003. Differences in the digestive tract characteristics of broiler chickens fed on complete pelleted diet or whole wheat added to pelleted protein concentrate. Br. Poult. Sci. 44:283–290. Gabriel, I., S. Mallet, M. Leconte, A. Travel, and J. P. Lalles. 2007. Effects of whole wheat feeding on the development of the digestive tract of broiler chickens. Anim. Feed Sci. Technol. 142:144– 162. Hedemann, M. S., S. Hojsgaard, and B. B. Jensen. 2003. Small intestinal morphology and activity of intestinal peptidases in piglets around weaning. J. Anim. Physiol. Anim. Nutr. (Berl.) 87:32– 41. Hetland, H., B. Svihus, and A. Krogdahl. 2003. Effects of oat hulls and wood shaving on digestion in broilers and layers fed diets based on whole or ground wheat. Br. Poult. Sci. 44:275–282. Hetland, H., B. Svihus, and V. Olaisen. 2002. Effect of feeding whole cereals on performance, starch digestibility and duodenal particle size distribution in broiler chickens. Br. Poult. Sci. 43:416–423. Kilburn, J., and H. M. Edwards. 2001. The response of broilers to the feeding of mash or pelleted diets containing corn of varying particle sizes. Br. Poult. Sci. 42:484–492. Kropp, L. B. 1975. Geese: America’s fourth fowl. Feedstuffs 16:32– 33. Langhout, D. J., J. B. Schutte, P. Van Leeuwen, J. Wiebenga, and S. Tamminga. 1999. Effect of dietary high- and low-methylated citrus pectin on the activity of the ileal microflora and morphology of the small intestinal wall of broiler chicks. Br. Poult. Sci. 40:340–347. Lott, B. D., E. J. Day, J. W. Deaton, and J. D. May. 1992. The effect of temperature, dietary energy level, and corn particle size on broiler performance. Poult. Sci. 71:618–624. Naya, D. E., G. Farfan, P. Sabat, M. A. Mendez, and F. Bozinovic. 2005. Digestive morphology and enzyme activity in the Andean toad Bufo spinulosus: Hard-wired or flexible physiology? Comp. Biochem. Physiol. A Mol. Integr. Physiol. 140:165–170. Nir, I., R. Hillel, G. Shefet, and Z. Nitsan. 1994. Effect of grain particle size on performance. 2: Grain texture interactions. Poult. Sci. 73:781–791. NRC. 1994. Nutrient Requirements of Poultry. 9th rev. ed. National Academy Press, Washington, DC. Preston, C. M., K. J. McCracken, and A. McAllister. 2000. Effect of diet form and enzyme supplementation on growth, efficiency and energy utilisation of wheat-based diets for broilers. Br. Poult. Sci. 41:324–331. Ravindran, V., Y. B. Wu, D. G. Thomas, and P. C. H. Morel. 2006. Influence of whole wheat feeding on the development of gastrointestinal tract and performance of broiler chickens. Aust. J. Agric. Res. 57:21–26.
594
Lu et al.
Reece, F. N., B. D. Lott, and J. W. Deaton. 1986. The effects of hammer mill screen size on ground corn particle size, pellet durability, and broiler performance. Poult. Sci. 65:1257–1261. Roche, M. 1981. Comportement alimentaire et motricit’e digestive des oiseaux. Reprod. Nutr. Dev. 21:781. SAS Institute. 1996. SAS User’s Guide: Statistics. Version 7.0. SAS Institute, Cary, NC. Shi, S. R., Z. Y. Wang, H. M. Yang, D. F. Sheng, and J. Lu. 2009. Optimization of fasting and excreta collection period in geese for true metabolisable energy assay. J. Appl. Anim. Res. 36:251– 254. Svihus, B., and H. Hetland. 2001. Ileal starch digestibility in growing broiler chickens fed on a wheat-based diet is improved by mash feeding, dilution with cellulose or whole wheat inclusion. Br. Poult. Sci. 42:633–637.
Svihus, B., E. Juvik, H. Hetland, and A. Krogdahl. 2004. Causes for improvement in nutritive value of broiler chicken diets with whole wheat instead of ground wheat. Br. Poult. Sci. 45:55–60. Taylor, R. D., and G. P. D. Jones. 2004. The incorporation of whole grain into pelleted broiler chicken diets. II: Gastrointestinal and digesta characteristics. Br. Poult. Sci. 45:237–246. Van Soest, P. J., J. B. Robertson, and A. Lewis. 1991. Methods for dietary fibre, neutral detergent fibre, and nonstarch poly-saccharides in relation to animal nutrition. J. Dairy Sci. 74:3583– 3597. Yang, H. M., Z. Y. Wang, J. Wang, S. R. Shi, and X. H. Zhu. 2009. Effects of caecectomy on digestibility of crude protein, calcium, phosphorus, neutral detergent fibre and acid detergent fibre in geese. Arch. Geflügelk. 73:189–192.
at 28 and 70 d of age were observed in birds fed the WC diet compared with those fed the GC diet. Intestinal wall thickness in the jejunum and crypt depth and intestinal wall thickness in the ileum were greater (P < 0.05) in WC-fed birds at 28 d of age. Villus height and intestinal wall thickness in the duodenum and villus height in the jejunum were greater in birds fed the WC diet compared with those fed the GC diet at 70 d of age, and birds fed the WC diet had a greater (P < 0.05) intestinal wall thickness, villus height, and crypt depth measurements in the ileum compared with those fed the GC diet. The retention ratio of CP and neutral detergent fiber were higher (P < 0.05) in birds fed the WC diet than in those fed the GC diet. Overall, no negative effect was observed in birds fed the WC diet compared with those maintained on the GC diet.
Key words: goose, whole corn, performance, digestive tract development, nutrient retention ratio 2011 Poultry Science 90:587–594 doi:10.3382/ps.2010-01054
INTRODUCTION
ing will significantly lower the cost of feed manufacture (Reece et al., 1986; Amerah et al., 2009). Moreover, it addresses consumer requirements for a more natural feeding system and can further improve bird performance (Gabriel et al., 2003, 2007). Many researchers have indicated that inclusion of whole grain could improve the performance and stimulate the development of the gastrointestinal tract in broilers (Gabriel et al., 2003). Taylor and Jones (2004) found that prepelleting inclusion of 200 g/kg of whole wheat had no effect on broiler performance but increased relative gizzard weights. Similar results were reported by Svihus et al. (2004) with prepelleting inclusion of 500 g/kg of whole wheat. The gastrointestinal tract represents a functional link among ingestion, digestion, and absorption. Furthermore, digestive constraints may, in part, influence traits such as growth, reproduction, and survival (Naya et al., 2005). For example, a more developed gizzard may enhance the grinding of feed that will increase the exposure of nutrients to digestive
Cereal grains are generally ground before incorporation into poultry feed. However, the use of whole grains has been of interest to researchers in Northern European countries, in Australia, and in Canada, to reduce the feed costs caused by transport, handling, and processing (Gabriel et al., 2007; Amerah and Ravindran, 2008; Amerah et al., 2008, 2009). Because decreasing feed particles to a finer size requires greater energy, any reduction in energy consumption used for grind©2011 Poultry Science Association Inc. Received August 8, 2010. Accepted December 11, 2010. 1 This work was financially supported by Scientific and Technical Support Program of Jiangsu Province (BE2009351) and National Technology System of Waterfowl Industrial (nycytx-45-22), P. R. China. 2 These authors contributed equally to the work. 3 Corresponding author: [email protected], [email protected]
587
588
Lu et al.
enzymes and improve nutrient digestion (Hetland et al., 2002; Gabriel et al., 2003), energy utilization (Preston et al., 2000), and performance (Ravindran et al., 2006). A well-developed gizzard is associated with improvement in gut motility (Ferket, 2000) and may prevent pathogenic bacteria from entering the intestinal tract (Bjerrum et al., 2005), thus reducing the risk of coccidiosis and other enteric diseases (Engberg et al., 2004; Bjerrum et al., 2005). Recently, Ravindran et al. (2006) studied the effects of a low inclusion level of whole wheat (100 g/kg from 1 to 21 d and 200 g/kg from 22 to 35 d) on the development of digestive organs. Gabriel et al. (2007) studied the effects of feeding whole wheat (200 g/kg in starter diet, 300 g/kg in grower diet, and 400 g/kg in finisher diet) on the development of the digestive tract of broiler chickens. In the current study, geese were selected as experimental animals. With the development of animal husbandry in china, goose production is becoming specialized and more widespread, and there are approximately 204 million geese in China (FAO-STAT, 2008). Geese are herbivorous waterfowl and they consume and digest large amounts of green grass, clover, and some plants (Kropp, 1975). They are able to utilize a highfiber diet because they have an efficient and powerful proventriculus and gizzard and because of the effective microbial breakdown of fiber in the cecum and large intestine (Yang et al., 2009). Most research has been reported in broilers, and most of the grains used have been wheat. Data on the effect of whole grains on other poultry (for example, geese) are rare. Thus, the objective of the current study was to investigate the influence of including whole corn in diets on the performance, digestive tract development, and nutrient retention ratio of geese from 8 to 70 d of age.
MATERIALS AND METHODS Animal and Housing The experimental procedures were approved by the Yangzhou University Animal Care and Use Committee. A total of 112 Yangzhou geese, 7 d old and with similar BW, produced by the same flock of geese, were obtained from a commercial hatchery. These birds were distributed to 8 pens of 14 birds/pen (7 male, 7 female) according to similar pen weight. Each treatment was represented by 4 replicates (pens). The pens were equipped with drinkers and individual feeders. The birds were transferred to grower pens (4 m × 6 m; in the same room) at 29 d of age. The room temperature was maintained at 28°C for the first week of the experiment and was subsequently gradually reduced to 24°C by 21 d of age, after which no heat was provided. The birds received 20 h of constant lighting during the period from 8 to 28 d, after which the geese were under natural daylight. Body weights were recorded at 7, 28, 49, and
70 d of age and feed intake by pen was measured on a daily basis. Mortality was recorded as it occurred, and G:F values were corrected for the BW of any birds that died during the course of the experiment.
Diets All birds were provided corn–soybean-based diets, and 2 particle sizes of corn grain were used: ground corn (GC) and whole corn (WC). To create the GC, the WC was ground in a hammer mill to pass through a screen size of 2 mm. The diets (Table 1), containing GC or WC plus soybean meal, fish meal, and alfalfa meal, were formulated to meet or exceed NRC (1994) recommendations for major nutrients for geese. The diets differed only by the corn grain size. The diets, in mash form, were offered ad libitum to each replicate. Water was freely available throughout the trial.
Digestive Tract and Intestinal Morphology Measurements On d 28 and 70, 4 birds from each replicate (2 male, 2 female) with BW closest to the mean weight of the pen were killed by cervical dislocation. Two of these birds (1 male, 1 female) were used for measurements of the digestive tract and the other 2 birds (1 male, 1 female) were used for the microscopic study of intestinal morTable 1. Composition and calculated analysis (g/kg, as fed) of the experimental diets1 Item
8–28 d
29–70 d
Ingredient Corn Soybean meal Fish meal Alfalfa meal Soybean oil Calcium hydrogen phosphate Limestone Salt Vitamin and trace mineral premix2 Composition3 ME4 (MJ/kg) CP Crude fiber Calcium Available phosphorus NaCl Methionine Lysine
640 270 30 20 0 18 9 3 10 11.63 190.1 34.8 10.8 6.0 3.7 4.5 10.2
615 136 30 160 20 19 8 2 10 12.17 161.8 59.6 1.13 6.3 3.1 4.3 7.4
1Corn
was provided as either ground or whole. per kilogram of diet: vitamin A (retinyl acetate), 30 mg; vitamin D3 (cholecalciferol), 0.5625 mg; vitamin E (di-α-tocopheryl acetate), 150 mg; vitamin K (2-methyl-1,4-naphthoquinone), 100 mg; thiamin, 50 mg; riboflavin, 600 mg; pyridoxine, 100 mg; vitamin B12 (cobalamin), 1 mg; nicotinic acid, 3 g; pantothenic acid, 900 mg; folic acid, 50 mg; biotin, 4 mg; choline, 35 g; Fe, 6 g; Cu, 1 g; Mn, 9.5 g; Zn, 9 g; I, 50 mg; Se, 30 mg. 3Analyzed values given for CP, crude fiber, calcium, and available phosphorus. Calculated values given for NaCl, methionine, and lysine. 4The values are calculated from ingredient AME values for chickens. 2Supplied,
589
WHOLE CORN IN GOOSE DIETS
phology. On d 49, 2 birds were killed for measurements of the digestive tract. The live weight was measured on 7, 28, 49, and 70 d of age, and weights of digestive tract segments from the proventriculus to the ceca of each bird were determined. The length of each intestinal segment was determined with a flexible tape on a glass surface to prevent inadvertent stretching. The length (±0.01 cm) of the small intestine (from the pyloric junction to the ileocecal junction), the length of the duodenum (from the pyloric junction to the most distal point of insertion of the duodenal mesentery), the length of the jejunum (from the most distal point of insertion of the duodenal mesentery to the junction with Meckel’s diverticulum), the length of the ileum (from the junction with Meckel’s diverticulum to the ileocecal junction), and the length of cecum were determined. After division and freeing of each intestinal segment, separating all connective tissue, and fat and removing the content with ice-cold saline flushing, the empty weights (±0.01 g) and lengths of each segment were determined along with those of the proventriculus and the gizzard. The relative values were calculated as a ratio of live BW. For intestinal morphological examinations, sections from the middle of the duodenum, jejunum, and ileum (about 2 cm in length) were excised and flushed with ice-cold saline and immediately placed in Bouin’s fluid. Samples were transferred into 70% ethanol after 24 h. Each fixed sample was then embedded in wax and sectioned at a thickness of 7 µm, stained with alcian blue and hematoxylin-eosin, and examined by light microscopy. Six intestinal segments were fixed in each slide, and the slides were viewed on a Zeiss Axiophot microscope (Carl Zeiss, Oberkochen, Germany). Visual measurements of villus height, crypt depth, and intestinal wall thickness were made on 10 villi at 40× and 100× magnifications using imaging software (LYWN-HP Super CCD, Liyang, Chengdu, P. R. China). The variables measured were villus height (the distance from the apex of the villus to the junction of the villus and crypt), crypt depth (the distance from the junction to the basement membrane of the epithelial cell at the bottom of the crypt), and intestinal wall thickness.
Determination of Nutrient Retention Ratio Nutrient retention ratio was determined according to the procedure of Yang et al. (2009) and Shi et al. (2009). At 70 d of age, 4 male geese from each group (1 bird/ pen) with BW closest to the mean weight of the group were selected and housed separately in metabolism cages (75 cm × 65 cm × 35 cm) with wire floors, equipped with individual feeders and self-drinking systems, and the data were recorded individually. Housing temperature was maintained at 24°C. The birds were allowed ad libitum access to water and diet (29–70 d) for 10 d. The technique for geese (24 h for fasting + 24 h for excreta collection) advised by Shi et al. (2009) was used
in this experiment. After fasting for 24 h, all birds were tube fed 70 g of diet (29–70 d). After crop intubation, excreta were collected and dried to a constant weight at 65°C, after reaching equilibrium with the atmospheric moisture for 24 h, weighed, and ground to pass through a 40-mesh sieve. The excreta was immediately frozen and stored at −20°C for further analysis. Samples were analyzed for total N using the microKjeldahl method (990.03; AOAC, 2000). Crude protein was calculated as N × 6.25. Calcium was determined by atomic absorption spectrophotometry (927.02; AOAC, 2000). Phosphorus was determined photometrically as orthophosphate from filtered ash solutions using the vanado-molybdate method. Ashing of samples was performed at 550°C for 12 h. Crude fiber was measured by sequential extraction with diluted acid and alkali (962.09; AOAC, 2000). Neutral detergent fiber (NDF) and acid detergent fiber were determined sequentially as described by Van Soest et al. (1991) and expressed on an ash-free basis. The nutrient retention ratio was calculated using the following formula: nutrient retention ratio = (feed intake × nutrientdiet − excreta output × nutrientexcreta)/ (feed intake × nutrientdiet) × 100%.
Statistical Analysis Data were compared in a completely randomized design by the one-tailed t-test of SAS software (SAS Institute, 1996). Statements of significance were based on P < 0.05 unless otherwise stated.
RESULTS Bird Performance During the periods from 8 to 28 and 29 to 49 d of age, daily feed intake of WC-fed birds (P < 0.05) was lower than that of GC-fed birds (Table 2). However, no significant difference (P > 0.05) in daily feed intake was observed from 50 to 70 and 8 to 70 d of age. Daily weight gain tended to decrease (P = 0.054) in birds fed the WC diet from 8 to 28 d of age, whereas WC in diet had no effect (P > 0.05) on the daily weight gain from 29 to 49, 50 to 70, and 8 to 70 d of age. Birds fed the WC diet tended to have improved (P = 0.070) G:F from 50 to 70 d of age compared with that of birds maintained on GC diet, but no effect (P > 0.05) was found in other periods.
Digestive Tract Measurements The effects of WC feeding on the relative tissue weights of the various gastrointestinal components of geese are shown in Table 3. The relative weights of the
590
0.1423 0.1871 0.014 0.070 0.3151 0.2986 0.012 0.376 2GC
1Each
value represents the mean of 4 replicates (8–28 d, 14 birds/replicate; 29–49 d, 10 birds/replicate; 50–70 d, 8 birds/replicate). = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole).
0.4913 0.4915 0.007 0.985 170.03 162.75 3.233 0.163 222.49 214.26 8.658 0.527 196.49 186.44 1.436 0.003 91.10 87.56 0.803 0.021 46.02 46.30 1.245 0.881 31.36 40.19 3.166 0.096 44.73 43.03 0.504 0.054 GC WC SEM Significance
61.96 55.67 2.550 0.132
50–70 d 50–70 d 29–49 d 8–28 d
Daily feed intake (g/bird)
8–70 d 50–70 d 29–49 d 8–28 d
During the period from 8 to 28 d of age, birds fed the WC diet tended to reduce daily feed intake and daily weight gain, as has been reported in broilers with access to whole wheat from 8 to 15 d of age (Gabriel et al., 2007). However, no effect was found on G:F from 8 to 28 d. Daily feed intake of birds fed the WC diet from 29 to 49 d of age was reduced compared with that of birds fed the GC diet, whereas no significant differences in daily feed intake were observed from 50 to 70 and 8 to 70 d of age. The birds were introduced to the WC diet at 7 d of age and had difficulties swallowing the WC diet during the first few days of life, as observed in broilers (Ravindran et al., 2006). Birds fed the WC diet improved G:F from 50 to 70 d of age, but
Treatment2
DISCUSSION
Daily weight gain (g/bird)
The retention ratios of CP, calcium, phosphorus, and fiber species are presented in Table 6. No significant difference (P > 0.05) was found in the retention ratios of calcium and phosphorus between WC-fed birds and GC-fed birds. However, the retention ratio of CP was generally higher (P < 0.05) in birds fed the WC diet. In addition, birds fed the GC diet improved (P < 0.05) the retention ratio of NDF, whereas no effect was found on the retention ratio of acid detergent fiber.
Table 2. Influence of whole corn feeding on the daily weight gain (g), daily feed intake (g), and G:F of geese1
Nutrient Retention Ratio
8–70 d
Intestinal Morphology Histological measurements of the villus, crypts, and intestinal wall were performed at 28 and 70 d of age (Table 5). At 28 d of age, the intestinal wall thickness in the jejunum, crypt depth, and intestinal wall thickness in the ileum were generally shorter (P < 0.05) in birds fed the GC diet compared with those fed the WC diet. At 70 d of age, villus height and intestinal wall thickness in the duodenum and villus height in the jejunum were greater (P < 0.05) in birds fed the WC diet, and birds fed the WC diet had greater (P < 0.05) villus height, crypt depth, and intestinal wall thickness measurements in the ileum compared with those fed the GC diet.
29–49 d 8–28 d
G:F (g/g)
8–70 d
gizzard and duodenum of WC-fed birds were greater (P < 0.05) than those of GC-fed birds at 28 d of age, but the relative weights of the jejunum, ileum, and ceca were not changed (P > 0.05). Similar results were found at 70 d of age; a diet effect was observed in the relative weights of the gizzard and duodenum, with a lower value (P < 0.05) in GC-fed birds. Higher relative weights of the proventriculus and gizzard were observed (P < 0.05) in birds fed the WC diet at 49 d of age, although no significant effect (P > 0.05) was found on the wet tissue weight of gut components. Relative lengths of various intestinal segments of geese at 28, 49, and 70 d of age are shown in Table 4. However, no effect (P > 0.05) was found on the relative length.
0.2708 0.2846 0.007 0.229
Lu et al.
591
WHOLE CORN IN GOOSE DIETS Table 3. Influence of whole corn feeding on the relative weights of gastrointestinal tract (g/kg) of geese at 28, 49, and 70 d of age1,2 Time and treatment3 28 d GC WC SEM Significance 49 d GC WC SEM Significance 70 d GC WC SEM Significance
Proventriculus
Gizzard
Duodenum
Jejunum
Ileum
Cecum
6.12 6.25 0.186 0.608 5.37 7.44 0.459 0.018 3.68 3.49 0.326 0.698
52.13 57.28 0.430 <0.001 34.28 40.13 1.334 0.021 36.36 43.45 1.714 0.026
6.46 7.65 0.281 0.024 4.62 5.33 0.252 0.094 2.46 3.28 0.232 0.046
15.71 15.72 0.248 0.978 11.55 11.34 0.983 0.886 6.02 6.66 0.540 0.434
14.97 15.39 0.453 0.536 9.65 8.87 0.582 0.380 6.61 4.66 0.841 0.151
2.92 3.05 0.145 0.563 2.90 2.87 0.196 0.920 1.54 2.52 0.765 0.400
1Each
value represents the mean of 4 replicates of 2 geese each. gizzard, duodenum, jejunum, ileum, and cecum values calculated as a ratio of live BW. 3GC = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole). 2Proventriculus,
no effect was found in other periods. In brief, results in this study are in agreement with those of studies using whole wheat instead of ground wheat from the second or third week of life, leading to no or positive effects on performance and feed efficiency during the overall rearing period (Preston et al., 2000; Hetland et al., 2002; Gabriel et al., 2003, 2007; Engberg et al., 2004; Svihus et al., 2004). Most studies were reported in broilers and focused on feed particle size. Provision of 200 g of whole wheat/kg in a mixed feeding system had no effect on the weight gain and feed efficiency in broilers (Amerah and Ravindran, 2008). Amerah et al. (2008) found that corn ground through a hammer mill screen opening of 7 mm, which resulted in coarse particles [geometric mean diameter (GMD): 0.528 mm], significantly decreased 21-d BW and increased F:G compared with corn ground through a screen opening of 1 mm (GMD: 0.297 mm). Particle
size influenced both BW and F:G, with coarse grinding (GMD: 1.20 mm) decreasing BW at 21 d and increasing F:G in corn-based diets (Lott et al., 1992). Kilburn and Edwards (2001) also found improvement in F:G and true ME when the diet included medium ground corn (GMD: 0.87 mm) compared with that made from coarse corn (GMD: 2.90 mm). Reece et al. (1986), however, found that the corn particle size (GMD: 0.68 vs. 1.29 mm) had no effect on performance when crumbled or pelleted diets were offered. The results of the current study suggest that WC diet had no negative effect on bird performance. Feeding the WC diet led to modifications of the upper part of the digestive tract (proventriculus, gizzard, duodenum). However, different results of the proventriculus are found in wheat-fed broilers, with a dilation of the proventriculus in birds fed ground wheat compared with those fed whole wheat (Gabriel et al.,
Table 4. Influence of whole corn feeding on the relative lengths of gastrointestinal tract (cm/kg) of geese at 28, 49, and 70 d of age1,2 Time and treatment3 28 d GC WC SEM Significance 49 d GC WC SEM Significance 70 d GC WC SEM Significance 1Each
Small intestine
Duodenum
Jejunum
Ileum
Cecum
145.95 148.27 2.983 0.603 83.71 84.43 4.849 0.920 62.16 60.87 2.213 0.693
25.55 28.00 0.869 0.092 13.15 14.39 0.375 0.058 10.38 11.48 0.451 0.136
61.00 63.11 0.914 0.152 33.44 34.54 2.186 0.735 25.10 25.93 1.229 0.648
59.41 57.15 1.855 0.422 30.51 31.57 1.180 0.547 23.86 22.68 1.138 0.491
16.25 15.53 0.707 0.497 9.21 9.69 0.603 0.604 13.91 12.78 0.821 0.368
value represents the mean of 4 replicates of 2 geese each. intestine, duodenum, jejunum, ileum, and cecum values calculated as a ratio of live BW. Small intestine = duodenum + jejunum + ileum. 3GC = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole). 2Small
592
Lu et al.
Table 5. Influence of whole corn feeding on villus height, crypt depth, and intestinal wall thickness (μm) of geese at 28 and 70 d of age1 Duodenum Time and treatment2 28 d GC2 WC3 SEM Significance 70 d GC2 WC3 SEM Significance
Jejunum
Ileum
Villus height
Crypt depth
Intestinal wall thickness
Villus height
Crypt depth
Intestinal wall thickness
Villus height
Crypt depth
Intestinal wall thickness
656.35 547.85 35.381 0.073 786.56 1,127.71 28.935 <0.001
134.61 152.44 13.853 0.398 114.62 119.94 4.631 0.448
187.34 187.27 18.195 0.998 271.17 320.31 12.404 0.031
801.79 735.86 57.193 0.446 723.48 1,059.27 18.753 <0.001
100.47 134.60 11.343 0.077 108.36 119.39 3.408 0.062
161.13 221.65 16.282 0.039 258.61 263.10 5.027 0.550
575.60 578.98 26.350 0.931 657.60 744.66 15.158 0.007
75.50 113.67 9.489 0.029 89.28 120.40 3.893 0.001
168.31 273.50 16.431 0.004 261.93 304.77 9.671 0.020
1Each 2GC
value represents the mean of 4 replicates of 2 geese each. = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole).
2003). The present data showed that the relative weight of the gizzard was greater in birds fed the WC diet. Similar findings have been reported with the use of whole grains in several studies (Engberg et al., 2004; Gabriel et al., 2007) and were attributed to the increased frequency of contraction of this organ (Roche, 1981) to reduce whole grains to fine particles. Promotion of gizzard development by whole grain is a strategy that has been found to prevent potentially pathogenic bacteria from entering the intestinal tract (Engberg et al., 2004). Moreover, the stronger mechanical development of the gizzard leads to smaller particle size of digesta in the intestine, which may increase digestion of all dietary compounds as observed for starch (Svihus and Hetland, 2001). However, the WC feeding in the current study had no effect on the relative length of the different intestinal segments. The effect of WC feeding was observed only in the relative weight of the duodenum, with a greater value for whole grains at 28 and 70 d of age, which is contrary to many reports: a lower weight of the duodenum was reported with whole wheat (Gabriel et al., 2003) and with a coarse particle diet compared with a fine particle diet (Nir et al., 1994). Other researches showed no modification of relative size of intestinal segments with substitution of ground wheat with whole wheat (Engberg et al., 2004; Ravindran et al., 2006). This can be explained that ef-
fects on the modification of digestive tract depend on grain type as reported by Amerah et al. (2008), who found that birds fed corn-based diets had a relatively heavier gizzard than those fed wheat-based diets. Intestinal wall thickness in the jejunum, crypt depth, and intestinal wall thickness in the ileum were greater in WC-fed birds at 28 d of age. Moreover, WC feeding had positive effects in the 3 segments of the small intestine at 70 d of age. Similar findings have been reported by Amerah and Ravindran (2008), who found that birds fed pelleted diets had a greater mucosal extent, villus height, and crypt depth measurements compared with those fed mash diets. However, the effect of feeding whole wheat was observed only in the duodenum (Gabriel et al., 2007), with crypt depth significantly decreased. The increased crypt depth in the current study was observed just in the ileum, which may be attributed to an increase in some bacterial populations, as observed in feeding whole wheat (Engberg et al., 2004). This may be related to an increased secretory activity such as a lower mucus production, goblet cells being particularly concentrated in the crypts (Langhout et al., 1999), and may also be related to an increase in cell turnover as shown by relationship between crypt depth and cell proliferation (Hedemann et al., 2003). Increased villus height and unchanged crypt depth in the duodenum and jejunum might indicate a general
Table 6. Influence of whole corn feeding on the retention ratio of CP, calcium, phosphorus, and fiber species1 (%) Treatment2
CP
Calcium
Phosphorus
NDF3
ADF4
GC WC SEM Significance
62.61 67.07 0.549 0.001
47.77 49.12 1.229 0.465
47.07 49.08 2.953 0.649
29.28 35.53 1.149 0.009
40.74 42.10 0.611 0.167
1Each
value represents the mean of 4 replicates of 1 bird each. = ground corn (corn was provided as ground); WC = whole corn (corn was provided as whole). 3NDF = neutral detergent fiber. 4ADF = acid detergent fiber. 2GC
WHOLE CORN IN GOOSE DIETS
increase in the digestive and absorptive capacity of the proximal small intestine in response to the greater flow of nutrients. It also showed that the intestinal structure was more oriented to digestion, with improved absorptive and hydrolysis potential, than to nutrient requirement for intestinal maintenance. In the current study, the nutrient retention ratio of CP and NDF were higher in birds fed the WC diet than in those fed the GC diet. Similar findings in starch digestibility were reported with inclusion of wood shavings (Amerah et al., 2009), coarse insoluble fiber (Hetland et al., 2003), and whole wheat (Svihus and Hetland, 2001; Hetland et al., 2002; Svihus et al., 2004). The results of the present study can probably be explained by the larger gizzard sizes and increased villus height observed in birds given the WC diet. A large, well-developed gizzard improves gut motility (Ferket, 2000) and may increase cholecystokinin release (Svihus et al., 2004), which in turn stimulates the secretion of pancreatic enzymes and gastroduodenal reflux (Duke, 1992). Hetland et al. (2003) reported that the total amount of bile acids in the gizzard increased in layers with access to wood shavings, indicating increased gastroduodenal reflux. On the other hand, a well-developed gizzard functions as a regulator of feed intake and improves nutrient retention. The findings of the current study support this thesis and it appears that WC in goose diets will have beneficial effects on digestive tract development and improve the nutrient retention ratio of CP and NDF. In summary, the data showed that daily weight gain of birds fed the WC diet was lower than that of birds fed the GC diet from 8 to 28 d of age, but feeding WC did not affect daily weight gain from 8 to 70 d of age. Higher relative weights of the gizzard at 28, 49, and 70 d of age, proventriculus at 49 d of age, and duodenum at 28 and 70 d of age were observed in birds fed WC diet compared with those fed the GC diet. Compared with birds fed the GC diet, villus height and intestinal wall thickness in the duodenum and villus height in the jejunum were greater in birds fed the WC diet at 70 d of age, and greater villus height, crypt depth, and intestinal wall thickness were found in the ileum. Moreover, birds fed the WC diet had improved retention ratio of CP and NDF. Thus, heavier gizzards, increased villus height, and the positive results on the retention ratio seemed sufficient to allow using WC in goose diet.
ACKNOWLEDGMENTS This work was financially supported by Scientific and Technical Support Program of Jiangsu Province (BE2009351), and National Technology System of Waterfowl Industrial (nycytx-45-22), P. R. China.
REFERENCES Amerah, A. M., and V. Ravindran. 2008. Influence of method of whole-wheat feeding on the performance, digestive tract devel-
593
opment and carcass traits of broiler chickens. Anim. Feed Sci. Technol. 147:326–339. Amerah, A. M., V. Ravindran, and R. G. Lentle. 2009. Influence of insoluble fibre and whole wheat inclusion on the performance, digestive tract development and ileal microbiota profile of broiler chickens. Br. Poult. Sci. 50:366–375. Amerah, A. M., V. Ravindran, R. G. Lentle, and D. G. Thomas. 2008. Influence of feed particle size on the performance, energy utilization, digestive tract development, and digesta parameters of broiler starters fed wheat- and corn-based diets. Poult. Sci. 87:2320–2328. AOAC. 2000. Official Methods of Analysis. 17th ed. Association of Official Analytical Chemists, Gaithersburg, MD. Bjerrum, L., K. Pedersen, and R. M. Engberg. 2005. The influence of whole wheat feeding on Salmonella infection and gut flora composition in broilers. Avian Dis. 49:9–15. Duke, G. E. 1992. Recent studies on regulation of gastric motility in turkeys. Poult. Sci. 71:1–8. Engberg, R. M., M. S. Hedemann, S. Steenfeldt, and B. B. Jensen. 2004. Influence of whole wheat and xylanase on broiler performance and microbial composition and activity in the digestive tract. Poult. Sci. 83:925–938. FAO-STAT. 2008. Food and Agriculture Organization of the United Nations. http://faostat.fao.org/site/573/default.aspx#ancor Ferket, P. 2000. Feeding whole grains to poultry improves gut health. Feedstuffs 72:12–14. Gabriel, I., S. Mallet, and M. Leconte. 2003. Differences in the digestive tract characteristics of broiler chickens fed on complete pelleted diet or whole wheat added to pelleted protein concentrate. Br. Poult. Sci. 44:283–290. Gabriel, I., S. Mallet, M. Leconte, A. Travel, and J. P. Lalles. 2007. Effects of whole wheat feeding on the development of the digestive tract of broiler chickens. Anim. Feed Sci. Technol. 142:144– 162. Hedemann, M. S., S. Hojsgaard, and B. B. Jensen. 2003. Small intestinal morphology and activity of intestinal peptidases in piglets around weaning. J. Anim. Physiol. Anim. Nutr. (Berl.) 87:32– 41. Hetland, H., B. Svihus, and A. Krogdahl. 2003. Effects of oat hulls and wood shaving on digestion in broilers and layers fed diets based on whole or ground wheat. Br. Poult. Sci. 44:275–282. Hetland, H., B. Svihus, and V. Olaisen. 2002. Effect of feeding whole cereals on performance, starch digestibility and duodenal particle size distribution in broiler chickens. Br. Poult. Sci. 43:416–423. Kilburn, J., and H. M. Edwards. 2001. The response of broilers to the feeding of mash or pelleted diets containing corn of varying particle sizes. Br. Poult. Sci. 42:484–492. Kropp, L. B. 1975. Geese: America’s fourth fowl. Feedstuffs 16:32– 33. Langhout, D. J., J. B. Schutte, P. Van Leeuwen, J. Wiebenga, and S. Tamminga. 1999. Effect of dietary high- and low-methylated citrus pectin on the activity of the ileal microflora and morphology of the small intestinal wall of broiler chicks. Br. Poult. Sci. 40:340–347. Lott, B. D., E. J. Day, J. W. Deaton, and J. D. May. 1992. The effect of temperature, dietary energy level, and corn particle size on broiler performance. Poult. Sci. 71:618–624. Naya, D. E., G. Farfan, P. Sabat, M. A. Mendez, and F. Bozinovic. 2005. Digestive morphology and enzyme activity in the Andean toad Bufo spinulosus: Hard-wired or flexible physiology? Comp. Biochem. Physiol. A Mol. Integr. Physiol. 140:165–170. Nir, I., R. Hillel, G. Shefet, and Z. Nitsan. 1994. Effect of grain particle size on performance. 2: Grain texture interactions. Poult. Sci. 73:781–791. NRC. 1994. Nutrient Requirements of Poultry. 9th rev. ed. National Academy Press, Washington, DC. Preston, C. M., K. J. McCracken, and A. McAllister. 2000. Effect of diet form and enzyme supplementation on growth, efficiency and energy utilisation of wheat-based diets for broilers. Br. Poult. Sci. 41:324–331. Ravindran, V., Y. B. Wu, D. G. Thomas, and P. C. H. Morel. 2006. Influence of whole wheat feeding on the development of gastrointestinal tract and performance of broiler chickens. Aust. J. Agric. Res. 57:21–26.
594
Lu et al.
Reece, F. N., B. D. Lott, and J. W. Deaton. 1986. The effects of hammer mill screen size on ground corn particle size, pellet durability, and broiler performance. Poult. Sci. 65:1257–1261. Roche, M. 1981. Comportement alimentaire et motricit’e digestive des oiseaux. Reprod. Nutr. Dev. 21:781. SAS Institute. 1996. SAS User’s Guide: Statistics. Version 7.0. SAS Institute, Cary, NC. Shi, S. R., Z. Y. Wang, H. M. Yang, D. F. Sheng, and J. Lu. 2009. Optimization of fasting and excreta collection period in geese for true metabolisable energy assay. J. Appl. Anim. Res. 36:251– 254. Svihus, B., and H. Hetland. 2001. Ileal starch digestibility in growing broiler chickens fed on a wheat-based diet is improved by mash feeding, dilution with cellulose or whole wheat inclusion. Br. Poult. Sci. 42:633–637.
Svihus, B., E. Juvik, H. Hetland, and A. Krogdahl. 2004. Causes for improvement in nutritive value of broiler chicken diets with whole wheat instead of ground wheat. Br. Poult. Sci. 45:55–60. Taylor, R. D., and G. P. D. Jones. 2004. The incorporation of whole grain into pelleted broiler chicken diets. II: Gastrointestinal and digesta characteristics. Br. Poult. Sci. 45:237–246. Van Soest, P. J., J. B. Robertson, and A. Lewis. 1991. Methods for dietary fibre, neutral detergent fibre, and nonstarch poly-saccharides in relation to animal nutrition. J. Dairy Sci. 74:3583– 3597. Yang, H. M., Z. Y. Wang, J. Wang, S. R. Shi, and X. H. Zhu. 2009. Effects of caecectomy on digestibility of crude protein, calcium, phosphorus, neutral detergent fibre and acid detergent fibre in geese. Arch. Geflügelk. 73:189–192.