- Email: [email protected]
Effect of source of betaine on growth performance and carcass traits in lambs
Animal Feed Science and Technology 86 (2000) 71±82
Effect of source of betaine on growth performance and carcass traits in lambs C. FernaÂndeza,*, A. LoÂpez-Saezb, L. Gallegob, J.M. de la Fuentec a
Departamento TecnologõÂa Agroalimentaria, Div. ProduccioÂn Animal, Universidad Miguel HernaÂndez, EPSO, 03312-Orihuela, Alicante, Spain b E.T.S.I.A. Universidad de Castilla-La Mancha, 02071-Albacete, Spain c TROUW Nutrition EspanÄa, Ronda de Poniente 9, 28760-Tres Cantos, Madrid, Spain Received 18 June 1999; received in revised form 11 April 2000; accepted 17 April 2000
Abstract An experiment was conducted to determine the effect of the source of betaine and sex on growth performance and carcass characteristics of growing lambs. A factorial structure 32 with dietary betaine and sex as main effects were made. A total of 60 Manchego breed lambs with an initial weight of 13 kg were randomly distributed into 12 pens. Weaned males and females were fed on a starter diet until 20 kg live weight (LW) and then were changed to a ®nisher diets up to the slaughter live weight (approx. 28 kg). Within each feeding period, starter and ®nisher diets containing 0 or 2 g kgÿ1 betaine (betaine anhydrous or rumen escape betaine) were used to fed each group of male and female lambs. Effect of sex was observed on daily gain, feed conversion rate, fat thickness (FT), and carcass characteristics (p<0.001); faster growth and less lipids deposition were found in males versus females. No effect of source of betaine was found on growth performance and carcass traits in male lambs. Female takes 12 more days than males to reach the slaughter live weight and more lipid depositions was observed. Reduction in fat thickness, perirenal fat and intramuscular content of lipids were found in female lambs when they were fed the diet enriched in betaine anhydrous (p<0.05). Same effect for diet with rumen escape added betaine and control were observed in male and female lambs. # 2000 Elsevier Science B.V. All rights reserved. Keywords: Betaine; Betaine bypass; Growth performance; Carcass traits; Intramuscular fat; Lamb
*
Corresponding author. Fax: 34-966-749-677. E-mail address: [email protected] (C. FernaÂndez) 0377-8401/00/$ ± see front matter # 2000 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 7 - 8 4 0 1 ( 0 0 ) 0 0 1 5 0 - 4
72
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
1. Introduction Betaine is a natural occurring product found in many plant and animal species. Betaine is present in relatively large quantities in sugar beets and aquatic invertebrates but is not present in signi®cant quantities in most animal feedstuffs. Chemically, betaine is trimethylglycine and the major involvement of betaine in lipids metabolism is in its lipotropic activity. Choline is an essential part of the lecithin molecule. Lecithin facilitates the transport of fat through the body and choline can be partially replaced in the diet by betaine or methionine for production of essential phospholipids, provided the precursor for choline synthesis dimethylethanolamine. Betaine, as well as methionine, donate a methyl group to dimethylethanolamine to form trimethylethanolamine which is choline. Choline can then be used directly for the synthesis of lecithin (Saunderson and Mackinlay, 1990). The involvement of betaine in lipid metabolism offer interesting challenge in meat producing animals due to the current interest in producing lean meat. The use of dietary betaine in commercial swine diets has increased since Cadogan et al. (1993) reported a 14.8% decrease in backfat thickness in pigs fed betaine, although growth performance and carcass traits were not affected. An increase in longissimus muscle area (LMA) was also found in pigs (Lawrence et al., 1995; Smith et al., 1995), but in other studies betaine increased backfat thickness and decreased longissimus dorsi area (Haydon et al., 1995). Thus, even though betaine may affect growth performance and carcass characteristics of pigs, the effect is variable. Information on possible effects of betaine on growth performance and lipid deposition in growing lambs is scarce. In previous studies on the effect of betaine in lamb diets, FernaÂndez and Gallego (1996) did not observe changes in growth performance, but a reduction of 11% in subcutaneous fat thickness (FT) was evident (FernaÂndez et al., 1998a,b). The purpose of this experiment was to study the effect of two sources of betaine (betaine anhydrous and rumen escape betaine) on growth performance and carcass characteristics in both growing male and female lambs. 2. Materials and methods 2.1. Diets Six diets were formulated and betaine were added to four of them at 2 g kgÿ1. The ®rst three diets were used from weaning to 20 kg live weight (LW), with the ®rst having no betaine (C), the second 2 g kgÿ1 added betaine (B) and the third 2 g kgÿ1 of rumen escape betaine (EB). From 20 kg LW to slaughter, three ®nisher diets were formulated with the same proportions of added betaine (C, B and EB). The ingredients and chemical composition is in Table 1. A total of six groups (three male and three female groups) of lambs were fed the formulated diet with ad libitum availability of barley straw. Betaine (Cultor Feed Ingredients), rumen escape betaine (Soda Micropearls), feed ingredients and vitamin±mineral premix were provided by Trouw Nutrition EspanÄa S.A. The nutrient level of the diets were determined based on recommended values of INRA
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
73
Table 1 Ingredient and chemical composition of the dietsa Ingredient (g kgÿ1)
Rolled corn grain Rolled barley grain Rolled wheat grain Rolled rye grain Beet liquid molasses Soybean meal, 44% Fat protected, maxcare Betaine Rumen escape betainec Limestone Calcium bicarbonate Salt Calcium carbonate Vitamin/mineral premixd Chemical analysis Dry matter Ash, %DM Crude protein, %DM NDF, %DM Ether extract, %DM
Starter (12±20 kg LW)
Finisher (20±29 kg LW)
Cb
B
EB
C
B
EB
200 280 100 51 10 290 30 ± ± 5 5 6 18 5
200 280 100 49 10 290 30 2 ± 5 5 6 18 5
200 280 100 49 10 290 30 ± 2 5 5 6 18 5
300 300 100 14 10 210 25 ± ± 5 5 6 20 5
300 300 100 12 10 210 25 2 ± 5 5 6 20 5
300 300 100 12 10 210 25 ± 2 5 5 6 20 5
88.1 6.8 18.7 24.0 4.6
88.0 6.7 18.7 24.1 4.5
87.8 6.6 18.8 24.0 4.5
89.0 6.4 16.7 24.2 3.7
89.0 6.6 16.8 24.2 3.9
88.9 7.0 16.9 24.1 4.0
a
Animals also had ad libitum access to barley straw. C: control; B: betaine; EB: rumen escape betaine. c Microencapsulated (SODA Microsystems Division, Monaco). d Provided by Trouw Nutrition EspanÄa S.A. to give (ppm or UI per kilogram of diet) 12±20 kg LW Se: 30; I: 120; Co: 190; Cu: 1100; Fe: 4200; Zn: 27,000; Mn: 13,000; S: 69,000; Mg: 45,000; Vitamin A: 1,650,000 UI; Vitamin D3: 330,000; Vitamin E: 5000 ppm; Vitamin B2: 600; Vitamin B12: 2000 ppb; Vitamin C: 2000; Vitamin K: 180; nicotinic acid: 4000. 10±28 kg LW; Se: 30; I: 240; Co: 190; Cu: 1100; Fe: 4200; Zn: 27,000; Mn: 13,000; S: 69,000; Mg: 45,000; Vitamin A: 1,000,000 UI; Vitamin D3: 280,000; Vitamin E: 2000 ppm. b
(1988), and all diets were pelleted. Chemical analyses of diets were conducted according to the methods of AOAC (1995). 2.2. Animals A total of 60 Manchego breed lambs were placed at the facilities of the Experimental Farm of the University of Castilla-La Mancha. Male and female lambs were distributed in two sets of three randomized groups (10 lambs per group) and each randomly assigned to one of the three experimental diets. Each group of 10 lambs was then split in subgroups of ®ve lambs in order to have a replicated estimate of feed intake by treatment. Lambs were weaned at 13.190.31 kg and slaughtered at 28.410.70 kg LW. The groups were as follows: CF are female lambs fed the control diet, CM are male lambs fed the control diet, BF are female lambs fed the betaine added to the diet, BM are
74
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
male lambs fed the betaine added to the diet, EBF are female lambs and rumen escape betaine added to the diet, and EBM are male lambs fed rumen escape betaine. Throughout the experiment, the lambs were handled according to the principles for the care of animals in experimentation (NRC, 1985). 2.3. Experimental equipment Subcutaneous fat thickness and longissimus dorsi area was determined by ultrasound technology. The ultrasound image acquisition equipment consisted in an ultrasonic unit (Toshiba Sonolayer real-time ultrasonic machine, model SAL-32B), and a 5 MHz probe. The computer and image processing system consisted in a personal computer (486/ 33 MHz IBM-compatible computer), an image analyzer (Global Lab Image V2.1, Data Translation Inc., Marlboro, MA) and an image graEBer board (DT55 Vision-EZ, Data Translation, Marlboro, MA). A video cassette recorder (SABA Ultravideo 4A10) was used to record the ultrasound images on VHS tapes for subsequent review and manual measurements. 2.4. Ultrasound measurements Wool was removed from measurement areas by shearing to improve image retrieval at weaning and a total of six determinations were done each 10 days. The transducter was placed between the 12th and 13th rib lateral to the vertebral column and parallel to the rib following physical palpation and preparation. In addition, liquid vaseline was applied to the scanning site to improve conduction between the skin and the transducter. All measurements were taken on the left side at 4 cm from the vertebral column. After obtaining ultrasound recording, ultrasound FT was estimated on site using the internal electronic calipers of the ultrasound unit. Captured ultrasonic images were recorded on a standard VHS video cassette recorder and later viewed to determine LMA using computer/image analyzer software with a frame grabber boar (the same equipment mentioned above). The digital image was 76812 pixels and calibration was taken from the internal scale of the ultrasound machine and we obtained a pixel of 0.018 cm. A technician traced the periphery of the muscle (from video recorded images) to allow calculation of LMA by counting pixels and converting them to square centimeters. All scanning and interpretation of scans were done by the same technician. 2.5. Carcass measurements All 60 lambs were slaughtered at same body weight. Facilities of an industrial slaughterhouse and commercial slaughtering processes were used. The carcasses were hung in a conventional chill cooler at 68C for 24 h by a standard gambrel of 14 cm through each hock (tarsus), without the hind legs being crossed. Shoulders were hung freely, with forelegs not tied to the neck. Carcasses were then graded (Colomer-Rocher et al., 1986) by trained personnel as described ahead. Conformation score of the entire carcass was assessed visually. The scale is constituted by ®ve classes (EUROP classi®cation) as E: excellent, U: very good, R: good, O: normal,
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
75
and P: poor. The visual score for the level of external fat cover had ®ve classes as follows: 1very lean, 2lean, 3poor lean, 4fat, 5very fat. Each score class was accompanied by a sign (), (ÿ) or (), so assessment was actually on a 15-point scale. To evaluate the fat cover of kidneys, a subjective scale based upon the visual score of the level of internal kidney fat was as follows: 1kidneys almost without fat, 2kidneys partially cover of fat, 3kidneys completely cover of fat. Each score class was accompanied by a sign (), (ÿ) or (), so assessment was actually on a 9-point scale. These subjective classi®cations were converted to numeric values in order to analyze data, so for instance, excellent conformation (E) had the value 15, very fat external fat (5) had value 15, and the number 9 for kidneys completely covered of fat (3). Kidney fat was also weighed and recorded. Cold carcasses were halved carefully and the left side was obtained according to the standard methods and procedures for lamb carcass evaluation suggested by ColomerRocher et al. (1986). From the left side, the 12th and 13th rib was cut laterally to the vertebral column and parallel to the rib and subcutaneous FT over the rib eye muscle was measured with a caliper at the same anatomical point where measurements were taken in the live animal using ultrasonic equipment. At the same point LMA was traced on acetate paper and measured with a planimeter (Planix 5.6, Tamaya Digital Planimeter, Tamaya Technics Inc.). Intramuscular lipids content from longissimus muscle samples (12th and 13th rib) were obtained according to the method developed by Marmer and Maxwell (1981). 2.6. Data analysis Data were analyzed as a 32 (three diets and two sex) factorial design using the GLM procedures of SAS (1988). Means comparison among groups were carried out using the following contrasts: Contrast I, effect of control diet versus betaine diets (CF CM versus BF BM EBF EBM); Contrast II, effect of source of betaine (BF BM versus EBF EBM); Contrast III, effect of sex (CF BF EBF versus CM BM EBM); Contrast IV, interaction between dietsex (CF BM EBM versus CM BF EBF) and Contrast V, interaction between dietbetaine (BF EBM versus BM EBF). The FT and LMA during the growth trial were determined by ultrasound measurements. To examine the in¯uence of time on ultrasound measurements, a repeated measures analysis was used. Growth was divided into 10-day intervals from weaning onwards. A repeated measurement analysis was made in which orthogonal polynomial contrasts over time were analyzed. 3. Results and discussion 3.1. Growth performance No effect of betaine was observed on ®nal body weight of lambs (Table 2) feed intake, and daily gain but signi®cant differences (p<0.05) were found for daily gain between lambs fed betaine or rumen escape betaine. Contrast III was also signi®cant (p<0.001) for daily gain, males growing faster than females and reached the same slaughter weight at
76
Item
CFb Initial weight (kg) Slaughter weight (kg) Feed intake (g per day) Average daily gain (g per day) Feed conversion rate (g gÿ1) Ultrasound fat thickness (mm) Ultrasound LMA (cm2) a
Contrasta
Diets
12.89 29.32 1024 329 3.15 3.70 8.55
CM 13.57 29.16 1008 410 2.49 2.80 8.27
BF 12.89 27.90 1002 334 3.02 2.60 7.14
BM 13.46 28.47 1027 395 2.63 2.70 7.78
EBF 12.94 27.78 981 297 3.34 3.10 7.25
EBM 13.37 27.80 1014 380 2.70 2.70 7.03
S.E.M. 0.16 0.27 20.33 0.01 0.04 0.06 0.12
I c
NS 0.068 NS 0.098 NS 0.002 0.001
II
III
IV
V
NS NS NS 0.034 0.039 NS NS
0.094 NS NS 0.001 0.001 0.003 NS
NS NS NS NS NS 0.011 NS
NS NS NS NS NS NS NS
Contrast I: control vs. betaine; Contrast II: betaine vs. rumen escape betaine; Contrast III: female vs. male; Contrast IV: diet vs. sex; Contrast V: diet vs. betaine. CF: control female; CM: control male; BF: betaine female; BM: betaine male; EBF: rumen escape betaine female; EBM: rumen escape betaine male. c NS: not signi®cant (Pr>0.1). b
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Table 2 Effect of dietary betaine administration on growth performance
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
77
less age. The same tendency was observed for feed conversion rate, we found effect of sex (p<0.001; 2.61 versus 3.17 for males and females, respectively) and differences between the two sources of betaine (p<0.05; 2.83 versus 3.02 for B and EB, respectively). Again, no differences were found when the control group was compared with both betaine and rumen escape betaine groups. In a previous study with lambs (FernaÂndez and Gallego, 1996; FernaÂndez, 1998), betaine (2 g kgÿ1) neither affected feed conversion rate as in this trial (Contrast I). This is in agreement with results reported in pigs (Virtanen and Campbell, 1994; Smith et al., 1995), although Cadogan et al. (1993) no effect of betaine was reported on feed intake, average daily gain, and feed conversion rate. Haydon et al. (1995) and Mattews et al. (1998) reported that betaine affects growth performance of pigs, but the effect is variable being in¯uenced by crude protein and net energy content of the diet. Currently, there is a complete lack of information in small ruminants about the role of betaine on growth performance under different dietary levels of energy and protein, although some authors had indicated a positive effect of betaine on protein metabolism (Radcliffe and Egan, 1978; Mitchell et al., 1979; Xue and Snoswell, 1985; Puchala et al., 1995). Table 2 also shows ultrasound FT determined on lambs 24 h prior to slaughter and signi®cant differences were found. Lower (p<0.01) FT was found for betaine than control diet (2.8 versus 3.3 mm as average, respectively), and for males than females (2.7 versus 3.1 mm, respectively), but no signi®cant difference was found between betaine and rumen escape betaine. The interaction between diet and sex was also signi®cant (p<0.05) indicating that betaine reduced FT in females (2.6 for BF versus 3.7 and 3.1 mm for CF and EBF, respectively) and no effect was found in males (2.7 mm as average). However, rumen escape betaine did not promote any signi®cant effect, indicating that only unprotected betaine had a positive effect in reducing the subcutaneous fat at the 12th and13th rib level in female lambs but not in males. In the study of FernaÂndez (1998) lambs fed the diet enriched in betaine reduced FT 0.5 mm and no effect of sex was observed. These results are in agreement with previous ®ndings in pigs in which betaine signi®cantly reduced P2 fat thickness (p<0.05; Virtanen and Campbell, 1994). The reduction of backfat in pigs with P2 values around 20 mm was estimated to be 2±2.5 mm when betaine was supplemented at the rate of 1±2 g kgÿ1, which represents a proportional similar reduction to that we observed in the studies with lambs. The same tendency were reported in gilts by Cadogan et al. (1993) and Smith et al. (1995), but not by Haydon et al. (1995). Despite that, chicks given a diet with 0.6 g kgÿ1 betaine had a lower body fat concentration than those given diets enriched in methionine and choline (Saunderson and Mackinlay, 1990). In order to study in more detail the effect of diet and sex during growth, the evolution over time of ultrasonic determination of FT and LMA were made. These results are shown in Figs. 1 and 2, respectively. Using repeated measurement analysis of variance, a signi®cant effect of time (p<0.001) over treatments for FT were found. The effect of sex (p<0.001) and diet (p<0.05) were signi®cant, and interaction between treatments and time was observed (p<0.01). Time had a linear effect (p<0.001) on FT deposition in treatments CF, CM, EBF and EBM, and a quadratic effect (p<0.01) in treatments BF and BM. Therefore, betaine treatment seems to slow down fat deposition or lipid mobilization during later stages of growth, both in males and females. However, male lambs had
78
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Fig. 1. Effect of betaine inclusion into the diet and sex on the evolution of FT measured by ultrasound in growing lambs from weaning to slaughter (28.40.7 kg).
similar subcutaneous FT deposition independently if betaine is added to the diet or not. Lipid deposition in females was different, and reduction of FT was observed in lambs added betaine when compared with control and rumen escape betaine. According to this data, it seems that betaine reduced subcutaneous FT in animals that have more capacity for lipid deposition, similar to observations for chicks and pigs (Saunderson and Mackinlay, 1990; Virtanen and Campbell, 1994). This is in agreement with the results shown in Tables 2 and 3 (effect of source of betaine on carcass characteristics), where more FT, perirenal fat, external carcass fat score and internal kidneys fat score were found in females than males. Males reached slaughter LW 12 days before than females, on average, and no effect of betaine was found (Figs. 1 and 2). However, more time was
Fig. 2. Effect of betaine inclusion into the diet and sex on the evolution of LMA measured by ultrasound in growing lambs from weaning to slaughter (28.40.7 kg).
Item
CFb Hot carcass weight (kg) Cold carcass weight (kg) Dressing percentage (%) EUROP classi®cationd External carcass fat score (1±5)d Internal kidneys fat score (1±3)d Carcass fat thickness (mm) Carcass LMA (cm2) Perirenal fat (g) Intramuscular content of lipids (g 100 gÿ1) a
Contrasta
Diets
15.63 15.27 53.30 R 2 2 3.50 9.97 401.67 3.43
CM 14.61 14.22 50.07 R 2ÿ 2ÿ 2.00 10.45 220.00 2.51
BF 14.62 14.24 52.39 R 2 2 2.80 10.01 396.00 2.95
BM 14.27 13.80 50.08 R 2ÿ 2ÿ 2.00 10.52 245.50 3.28
EBF 14.50 14.16 52.23 R 2 2 3.70 9.83 405.00 3.01
EBM 13.86 13.50 49.88 R 2ÿ 2ÿ 2.30 10.11 217.00 2.74
S.E.M. 0.15 0.14 0.17 0.06 0.05 0.04 0.09 0.25 11.44 0.22
I 0.013 0.010 NS NS NS NS NS NS NS NS
II c
NS NS NS NS NS NS 0.006 0.059 NS NS
III
IV
V
0.025 0.015 0.001 0.016 0.003 0.001 0.001 0.017 0.001 NS
NS NS NS NS NS NS NS NS NS 0.050
NS NS NS NS NS NS NS NS NS 0.001
Contrast I: control vs. betaine; Contrast II: betaine vs. rumen escape betaine; Contrast III: female vs. male; Contrast IV: diet vs. sex; Contrast V: diet vs. betaine. CF: control female; CM: control male; BF: betaine female; BM: betaine male; EBF: rumen escape betaine female; EBM: rumen escape betaine male. c NS: not signi®cant (Pr>0.1). d Converted to numeric values for statistical analysis. b
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Table 3 Effect of dietary betaine administration on carcass characteristics
79
80
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
taken for females to reach slaughter LW, and therefore, more deposition of lipid was observed. It seems that anhydrous betaine is more effective in promoting lipid mobilization or distribution when the animal has more capacity to synthesize lipid tissue. Fig. 2 shows an effect of time over LMA by treatment. Treatment did not in¯uence LMA but the effect of time was signi®cant (p<0.001). By means of orthogonal polynomials contrast we observed a quadratic effect of time over LMA (p<0.05) but no differences in the slopes for treatments were observed. 3.2. Carcass characteristics The effect of betaine on carcass characteristics is shown in Table 3. Signi®cant differences (p<0.05) were found for hot and cold carcass weight. These differences could be due to control diets on which lambs had slightly greater slaughter weights than on betaine diets (29.24 versus 27.99 kg, respectively). No signi®cant differences among diets were found for dressing percentage (average 51.33%). However, signi®cant differences were found for the effect of sex (Contrast III), females having greater values of dressing percentage than males (p<0.001; 52.64 versus 50.01%, respectively). Other reports in the literature have indicated that betaine does not affect carcass traits in pigs (Smith et al., 1994; Cera and Schinckel, 1995), and our data are in agreement with these observations, with the exception of those reported by Mattews et al. (1998) where betaine increased dressing percentage. We did not ®nd signi®cant differences among diets in the conformation of the carcasses according to the EUROP scale. All carcasses were classi®ed as R with the exception of BF and EBF that were R (good), males having slightly better conformation that females (p<0.05; in Contrast III). In a previous study with lambs, FernaÂndez et al. (1998b) did not ®nd signi®cant differences for diets added betaine (2 g kgÿ1) or between sex. The EUROP classi®cation obtained was Rÿ but slaughtering weight was slightly lower (25.9 kg LW) than in the present trial (28.4 kg LW). External carcass fat, internal kidney fat score and perirenal fat (Table 3) were affected by sex (p<0.01) but not by betaine source. Females record higher classi®cation (2) and perirenal fat (401 g) than males (2ÿand 228 g), indicating the greater fatness of females than males. In the study by FernaÂndez et al. (1998b), they did not ®nd signi®cant differences for betaine and sex in external carcass fat, with an average classi®cation of 2, but internal kidney fat was affected (p<0.01) by betaine (2ÿ versus 2; betaine and control, respectively). Although redistribution or decrease fat deposition in pigs have been reported (Virtanen and Campbell, 1994), we have been unable to ®nd in the literature references to a positive effect of betaine on subjective carcass conformation or external fat score. Saunderson and Mackinlay (1990) have shown that betaine decreased fat of chicks. Treated chickens were heavier but leaner compared to control group chickens, and breast meat yield of the betaine group was 3.7% higher than control group. The present results also need to be viewed in context of the inherent protein and fat deposition potential of the lambs involved. Subcutaneous FT and LMA at the 12th and 13th rib level obtained on the carcass 24 h after slaughter are shown in Table 3. No signi®cant differences were observed for control versus betaine diets (Contrast I), although signi®cant differences were obtained (p<0.01
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
81
and p<0.05 for carcass FT and LMA, respectively) between sources of betaine (Contrast II). Thus, carcass FT was lower for betaine than rumen escape betaine (2.37 versus 3.03 mm, respectively) and LMA followed the opposite tendency (10.27 versus 9.97 cm2 for betaine and rumen escape betaine, respectively). Campbell et al. (1995), using betaine supplementation at 1.25 kg tÿ1 in pigs, observed a reduction of 2.0±2.5 mm of FT at P2 level and an increase of LMA of 2 cm2. However, Horcas et al. (1998) working with lambs did not report any reduction in lipid deposition when betaine was added to the ®nishing diets (3 mm as average). In order to evaluate if the reduction of FT was only in subcutaneous tissues or it affected other parts of the carcass, intramuscular content of lipids in longissimus muscle was measured. Intramuscular content of lipids is shown in Table 3 and neither the effect of diet nor that of sex was observed. In a previous study, FernaÂndez et al. (1998a) observed a lower concentration of intramuscular fat content in lambs fed on diets enriched in betaine compared to those fed a basal diet (2.58 versus 4.46 g 100 gÿ1), being the effect independent of sex. In this study interaction was observed and females had greater intramuscular contents of lipids for C and EB than males, but the opposite tendency was observed for B, where males had greater values than females (3.28 versus 2.95 g 100 gÿ1, respectively). There were means interactions between diet and sex (p<0.05), diet and betaine (p<0.001) indicating a reduction of intramuscular lipids in females fed with betaine. This may be due to the relative late deposition of intramuscular fat (Koohmaraie et al., 1995), the period when betaine seems to be more effective in lowering lipid accumulation. However, some compounds with methyl donor properties interact with fat metabolism (Percival et al., 1970) which suggest that the activity of some enzymes involved in lipid metabolism might also be involved. So, while reduction of subcutaneous fat may be considered as a positive effect of betaine, the reduction of intramuscular lipids needs further investigation. In summary, the effect of source of betaine on growth performance and carcass characteristics was variable. Results from this experiment indicate that dietary supplementation with rumen escape betaine had no effect on growth performance and carcass fatness in both males and females. Neither anhydrous betaine affected males but it promoted lower subcutaneous FT and fatness in females, probably due to the greater potential for response at higher rate of lipid deposition. Acknowledgements This work was partially supported by a Technology Contract with Trouw Nutrition EspanÄa S.A. References AOAC, 1995. Of®cial Methods of Analysis, 16th Edition. Association of Of®cial Analytical Chemists, Washington, DC. Cadogan, D.J., Campbell, R.G., Harrison, D., Edwards, A.C., 1993. The effects of betaine on the growth performance and carcass characteristics of female pigs. In: Batterham, E.S. (Ed.), Manipulating Pig Production. Australasian Pig Science Association, Attwood, Victoria, Australia, p. 219.
82
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Campbell, R.G., Cadogan, D.J., Morley, W.C., Uusitalo, R., Virtanen, E., 1995. Interrelationships between dietary methionine and betaine on the growth performance of pigs from 65 to 100 kg. J. Anim. Sci. 73 (Suppl. 1), 82 (Abstract). Cera, K,R., Schinckel, A.P., 1995. Carcass and performance responses to feeding betaine in pigs. J. Anim. Sci. 73 (Suppl. 1), 82 (Abstract). Colomer-Rocher, F., Delfa, R., Sierra, I., 1986. Cuadernos INIA (1988). 17, 19±41. FernaÂndez, C., 1998. UtilizacioÂn de bioproductos en la nutricioÂn de pequenÄos rumiantes; betaina en corderos. 1. Congreso Nordestino de ProduccioÂn Animal, Vol. 3. VII Simposium Nordestino de AlimentacioÂn de Rumiantes, SNPA, Fortaleza, Brazil, pp. 27±34. FernaÂndez, C., Gallego, L., 1996. Efecto de la betaõÂna sobre los rendimientos productivos y el nivel de engrasamiento en corderos de raza Manchega. XXI Jornadas Cientõ®cas de la SEOC, LogronÄo, EspanÄa, pp. 281±289. FernaÂndez, C., Gallego, L., LoÂpez-Bote, C.J., 1998a. Effect of betaine on fat content in growing lambs. Anim. Feed Sci. Technol. 73, 329±338. FernaÂndez, C., Gallego, L., Molina, A., de la Fuente, J.M., 1998. The effect of betaine on subcutaneous fat thickness. EAAP Publication No. 90, 446±450. Haydon, K.D., Campbell, R.G., Prince, T.J., 1995. Effect of dietary betaine additions and amino:calorie ratio on performance and carcass traits of ®nishing pigs. J. Anim. Sci. 73 (Suppl. 1), 83 (Abstract). Horcas, E., Cuartielles, M.I., Lahera, L.M., Delfa, R., 1998. UtilizacioÂn de betaõÂna en pienso de corderos al ®nalizar el cebo como factor retardador del engrasamiento. XXIII Jornadas Cientõ®cas de la SEOC, 95±97. INRA, 1988. In: Jarrige, G. (Ed.), Alimentation des Bovins, Ovins et Caprins. INRA, Paris, France, 476 pp. Koohmaraie, M., Shackelford, S.D., Wheeler, T.L., Lonergan, S.M., Doumit, M.E., 1995. A muscle hypertrophy condition in lamb (callipyge) Ð characterization of effects on muscle growth and meat quality traits. J. Anim. Sci. 73, 3596±3607. Lawrence, B.V., Schinckel, A.P., Adeola, O., Cera, K., 1995. Performance of pigs fed betaine from 60 to 110 kg body weight. J. Anim. Sci. 73 (Suppl. 1), 195. Marmer, W.N., Maxwell, R.J., 1981. Dry column method for the quantitative extraction and simultaneous class separation of lipids from muscle tissue. Lipids 16, 365±371. Mattews, J.O., Southern, L.L., Pontif, J.E., Higbie, A.D., Bidner, T.D., 1998. Interactive effects of betaine, crude protein, and net energy in ®nishing pigs. J. Anim. Sci. 76, 2444±2455. Mitchell, A.D., Chappell, A., Knox, K.L., 1979. Metabolism of betaine in the ruminant. J. Anim. Sci. 49, 764±774. National Research Council, 1985. Guide for the Care and Use of Laboratory Animals. Publication No. 85-23, NIH, Washington, DC. Percival, G.S., Dunn, S.H., Howe, J.M., Clark, H.E., 1970. Interaction between methionine, fat and choline in the growing rat. J. Nutr. 100, 664±670. Puchala, R., Sahlu, T., Herselman, M.J., Davis, J.J., 1995. In¯uence of betaine on blood metabolites on alpine and angora kids. Small Rum. Res. 18, 137±143. Radcliffe, B.C., Egan, A.R., 1978. The effect of diet and of methionine loading on activity of enzymes in the transulfuration pathway in sheep. Aust. J. Biol. Sci. 31, 105±114. SAS, 1988. SAS/STAT User's Guide, Release 6.03 Edition. SAS Institute Inc., Cary, NC, 1028 pp. Saunderson, C.L., Mackinlay, J., 1990. Changes in body weight, composition and hepatic enzyme activities in response to dietary methionine, betaine and choline levels in growing chicks. Br. J. Nutr. 63, 339±349. Smith, J.W., Owen, K.Q., Nelssen, J.L., Goodband, M.D., Tokach, M.D., Friesen, K.G., Lohrmann, T.L., Blum, S.A., 1994. The effects of dietary carnitine, betaine and chromium nicotinate supplementation on growth and carcass characteristics in growing ®nishing pigs. J. Anim. Sci. 72 (Suppl. 1), 274 (Abstract). Smith, J.W., Nelssen, J.L., Goodband, M.D., Tokach, M.D., Richert, B.T., Owen, K.Q., Bergstrom, J.R., Blum, S.A., 1995. The effects of supplementing growing ®nishing swine diets with betaine and (or) choline on growth and carcass characteristics. J. Anim. Sci. 73 (Suppl. 1), 83 (Abstract). Virtanen, E., Campbell, R., 1994. Reduzierung der Ruckenspeckdicke durch Einsatz von Betain bei Mastchweinen. Handbuch der tierischen Veredlung, Vol. 19. Verlag H. Kamlage, Onsnabruek, Deutschland, pp. 145±150. Xue, G.P., Snoswell, A.M., 1985. Regulation of methyl group metabolism in lactating ewes. Biochem. Int. 11, 381±385.
Effect of source of betaine on growth performance and carcass traits in lambs C. FernaÂndeza,*, A. LoÂpez-Saezb, L. Gallegob, J.M. de la Fuentec a
Departamento TecnologõÂa Agroalimentaria, Div. ProduccioÂn Animal, Universidad Miguel HernaÂndez, EPSO, 03312-Orihuela, Alicante, Spain b E.T.S.I.A. Universidad de Castilla-La Mancha, 02071-Albacete, Spain c TROUW Nutrition EspanÄa, Ronda de Poniente 9, 28760-Tres Cantos, Madrid, Spain Received 18 June 1999; received in revised form 11 April 2000; accepted 17 April 2000
Abstract An experiment was conducted to determine the effect of the source of betaine and sex on growth performance and carcass characteristics of growing lambs. A factorial structure 32 with dietary betaine and sex as main effects were made. A total of 60 Manchego breed lambs with an initial weight of 13 kg were randomly distributed into 12 pens. Weaned males and females were fed on a starter diet until 20 kg live weight (LW) and then were changed to a ®nisher diets up to the slaughter live weight (approx. 28 kg). Within each feeding period, starter and ®nisher diets containing 0 or 2 g kgÿ1 betaine (betaine anhydrous or rumen escape betaine) were used to fed each group of male and female lambs. Effect of sex was observed on daily gain, feed conversion rate, fat thickness (FT), and carcass characteristics (p<0.001); faster growth and less lipids deposition were found in males versus females. No effect of source of betaine was found on growth performance and carcass traits in male lambs. Female takes 12 more days than males to reach the slaughter live weight and more lipid depositions was observed. Reduction in fat thickness, perirenal fat and intramuscular content of lipids were found in female lambs when they were fed the diet enriched in betaine anhydrous (p<0.05). Same effect for diet with rumen escape added betaine and control were observed in male and female lambs. # 2000 Elsevier Science B.V. All rights reserved. Keywords: Betaine; Betaine bypass; Growth performance; Carcass traits; Intramuscular fat; Lamb
*
Corresponding author. Fax: 34-966-749-677. E-mail address: [email protected] (C. FernaÂndez) 0377-8401/00/$ ± see front matter # 2000 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 7 - 8 4 0 1 ( 0 0 ) 0 0 1 5 0 - 4
72
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
1. Introduction Betaine is a natural occurring product found in many plant and animal species. Betaine is present in relatively large quantities in sugar beets and aquatic invertebrates but is not present in signi®cant quantities in most animal feedstuffs. Chemically, betaine is trimethylglycine and the major involvement of betaine in lipids metabolism is in its lipotropic activity. Choline is an essential part of the lecithin molecule. Lecithin facilitates the transport of fat through the body and choline can be partially replaced in the diet by betaine or methionine for production of essential phospholipids, provided the precursor for choline synthesis dimethylethanolamine. Betaine, as well as methionine, donate a methyl group to dimethylethanolamine to form trimethylethanolamine which is choline. Choline can then be used directly for the synthesis of lecithin (Saunderson and Mackinlay, 1990). The involvement of betaine in lipid metabolism offer interesting challenge in meat producing animals due to the current interest in producing lean meat. The use of dietary betaine in commercial swine diets has increased since Cadogan et al. (1993) reported a 14.8% decrease in backfat thickness in pigs fed betaine, although growth performance and carcass traits were not affected. An increase in longissimus muscle area (LMA) was also found in pigs (Lawrence et al., 1995; Smith et al., 1995), but in other studies betaine increased backfat thickness and decreased longissimus dorsi area (Haydon et al., 1995). Thus, even though betaine may affect growth performance and carcass characteristics of pigs, the effect is variable. Information on possible effects of betaine on growth performance and lipid deposition in growing lambs is scarce. In previous studies on the effect of betaine in lamb diets, FernaÂndez and Gallego (1996) did not observe changes in growth performance, but a reduction of 11% in subcutaneous fat thickness (FT) was evident (FernaÂndez et al., 1998a,b). The purpose of this experiment was to study the effect of two sources of betaine (betaine anhydrous and rumen escape betaine) on growth performance and carcass characteristics in both growing male and female lambs. 2. Materials and methods 2.1. Diets Six diets were formulated and betaine were added to four of them at 2 g kgÿ1. The ®rst three diets were used from weaning to 20 kg live weight (LW), with the ®rst having no betaine (C), the second 2 g kgÿ1 added betaine (B) and the third 2 g kgÿ1 of rumen escape betaine (EB). From 20 kg LW to slaughter, three ®nisher diets were formulated with the same proportions of added betaine (C, B and EB). The ingredients and chemical composition is in Table 1. A total of six groups (three male and three female groups) of lambs were fed the formulated diet with ad libitum availability of barley straw. Betaine (Cultor Feed Ingredients), rumen escape betaine (Soda Micropearls), feed ingredients and vitamin±mineral premix were provided by Trouw Nutrition EspanÄa S.A. The nutrient level of the diets were determined based on recommended values of INRA
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
73
Table 1 Ingredient and chemical composition of the dietsa Ingredient (g kgÿ1)
Rolled corn grain Rolled barley grain Rolled wheat grain Rolled rye grain Beet liquid molasses Soybean meal, 44% Fat protected, maxcare Betaine Rumen escape betainec Limestone Calcium bicarbonate Salt Calcium carbonate Vitamin/mineral premixd Chemical analysis Dry matter Ash, %DM Crude protein, %DM NDF, %DM Ether extract, %DM
Starter (12±20 kg LW)
Finisher (20±29 kg LW)
Cb
B
EB
C
B
EB
200 280 100 51 10 290 30 ± ± 5 5 6 18 5
200 280 100 49 10 290 30 2 ± 5 5 6 18 5
200 280 100 49 10 290 30 ± 2 5 5 6 18 5
300 300 100 14 10 210 25 ± ± 5 5 6 20 5
300 300 100 12 10 210 25 2 ± 5 5 6 20 5
300 300 100 12 10 210 25 ± 2 5 5 6 20 5
88.1 6.8 18.7 24.0 4.6
88.0 6.7 18.7 24.1 4.5
87.8 6.6 18.8 24.0 4.5
89.0 6.4 16.7 24.2 3.7
89.0 6.6 16.8 24.2 3.9
88.9 7.0 16.9 24.1 4.0
a
Animals also had ad libitum access to barley straw. C: control; B: betaine; EB: rumen escape betaine. c Microencapsulated (SODA Microsystems Division, Monaco). d Provided by Trouw Nutrition EspanÄa S.A. to give (ppm or UI per kilogram of diet) 12±20 kg LW Se: 30; I: 120; Co: 190; Cu: 1100; Fe: 4200; Zn: 27,000; Mn: 13,000; S: 69,000; Mg: 45,000; Vitamin A: 1,650,000 UI; Vitamin D3: 330,000; Vitamin E: 5000 ppm; Vitamin B2: 600; Vitamin B12: 2000 ppb; Vitamin C: 2000; Vitamin K: 180; nicotinic acid: 4000. 10±28 kg LW; Se: 30; I: 240; Co: 190; Cu: 1100; Fe: 4200; Zn: 27,000; Mn: 13,000; S: 69,000; Mg: 45,000; Vitamin A: 1,000,000 UI; Vitamin D3: 280,000; Vitamin E: 2000 ppm. b
(1988), and all diets were pelleted. Chemical analyses of diets were conducted according to the methods of AOAC (1995). 2.2. Animals A total of 60 Manchego breed lambs were placed at the facilities of the Experimental Farm of the University of Castilla-La Mancha. Male and female lambs were distributed in two sets of three randomized groups (10 lambs per group) and each randomly assigned to one of the three experimental diets. Each group of 10 lambs was then split in subgroups of ®ve lambs in order to have a replicated estimate of feed intake by treatment. Lambs were weaned at 13.190.31 kg and slaughtered at 28.410.70 kg LW. The groups were as follows: CF are female lambs fed the control diet, CM are male lambs fed the control diet, BF are female lambs fed the betaine added to the diet, BM are
74
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
male lambs fed the betaine added to the diet, EBF are female lambs and rumen escape betaine added to the diet, and EBM are male lambs fed rumen escape betaine. Throughout the experiment, the lambs were handled according to the principles for the care of animals in experimentation (NRC, 1985). 2.3. Experimental equipment Subcutaneous fat thickness and longissimus dorsi area was determined by ultrasound technology. The ultrasound image acquisition equipment consisted in an ultrasonic unit (Toshiba Sonolayer real-time ultrasonic machine, model SAL-32B), and a 5 MHz probe. The computer and image processing system consisted in a personal computer (486/ 33 MHz IBM-compatible computer), an image analyzer (Global Lab Image V2.1, Data Translation Inc., Marlboro, MA) and an image graEBer board (DT55 Vision-EZ, Data Translation, Marlboro, MA). A video cassette recorder (SABA Ultravideo 4A10) was used to record the ultrasound images on VHS tapes for subsequent review and manual measurements. 2.4. Ultrasound measurements Wool was removed from measurement areas by shearing to improve image retrieval at weaning and a total of six determinations were done each 10 days. The transducter was placed between the 12th and 13th rib lateral to the vertebral column and parallel to the rib following physical palpation and preparation. In addition, liquid vaseline was applied to the scanning site to improve conduction between the skin and the transducter. All measurements were taken on the left side at 4 cm from the vertebral column. After obtaining ultrasound recording, ultrasound FT was estimated on site using the internal electronic calipers of the ultrasound unit. Captured ultrasonic images were recorded on a standard VHS video cassette recorder and later viewed to determine LMA using computer/image analyzer software with a frame grabber boar (the same equipment mentioned above). The digital image was 76812 pixels and calibration was taken from the internal scale of the ultrasound machine and we obtained a pixel of 0.018 cm. A technician traced the periphery of the muscle (from video recorded images) to allow calculation of LMA by counting pixels and converting them to square centimeters. All scanning and interpretation of scans were done by the same technician. 2.5. Carcass measurements All 60 lambs were slaughtered at same body weight. Facilities of an industrial slaughterhouse and commercial slaughtering processes were used. The carcasses were hung in a conventional chill cooler at 68C for 24 h by a standard gambrel of 14 cm through each hock (tarsus), without the hind legs being crossed. Shoulders were hung freely, with forelegs not tied to the neck. Carcasses were then graded (Colomer-Rocher et al., 1986) by trained personnel as described ahead. Conformation score of the entire carcass was assessed visually. The scale is constituted by ®ve classes (EUROP classi®cation) as E: excellent, U: very good, R: good, O: normal,
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
75
and P: poor. The visual score for the level of external fat cover had ®ve classes as follows: 1very lean, 2lean, 3poor lean, 4fat, 5very fat. Each score class was accompanied by a sign (), (ÿ) or (), so assessment was actually on a 15-point scale. To evaluate the fat cover of kidneys, a subjective scale based upon the visual score of the level of internal kidney fat was as follows: 1kidneys almost without fat, 2kidneys partially cover of fat, 3kidneys completely cover of fat. Each score class was accompanied by a sign (), (ÿ) or (), so assessment was actually on a 9-point scale. These subjective classi®cations were converted to numeric values in order to analyze data, so for instance, excellent conformation (E) had the value 15, very fat external fat (5) had value 15, and the number 9 for kidneys completely covered of fat (3). Kidney fat was also weighed and recorded. Cold carcasses were halved carefully and the left side was obtained according to the standard methods and procedures for lamb carcass evaluation suggested by ColomerRocher et al. (1986). From the left side, the 12th and 13th rib was cut laterally to the vertebral column and parallel to the rib and subcutaneous FT over the rib eye muscle was measured with a caliper at the same anatomical point where measurements were taken in the live animal using ultrasonic equipment. At the same point LMA was traced on acetate paper and measured with a planimeter (Planix 5.6, Tamaya Digital Planimeter, Tamaya Technics Inc.). Intramuscular lipids content from longissimus muscle samples (12th and 13th rib) were obtained according to the method developed by Marmer and Maxwell (1981). 2.6. Data analysis Data were analyzed as a 32 (three diets and two sex) factorial design using the GLM procedures of SAS (1988). Means comparison among groups were carried out using the following contrasts: Contrast I, effect of control diet versus betaine diets (CF CM versus BF BM EBF EBM); Contrast II, effect of source of betaine (BF BM versus EBF EBM); Contrast III, effect of sex (CF BF EBF versus CM BM EBM); Contrast IV, interaction between dietsex (CF BM EBM versus CM BF EBF) and Contrast V, interaction between dietbetaine (BF EBM versus BM EBF). The FT and LMA during the growth trial were determined by ultrasound measurements. To examine the in¯uence of time on ultrasound measurements, a repeated measures analysis was used. Growth was divided into 10-day intervals from weaning onwards. A repeated measurement analysis was made in which orthogonal polynomial contrasts over time were analyzed. 3. Results and discussion 3.1. Growth performance No effect of betaine was observed on ®nal body weight of lambs (Table 2) feed intake, and daily gain but signi®cant differences (p<0.05) were found for daily gain between lambs fed betaine or rumen escape betaine. Contrast III was also signi®cant (p<0.001) for daily gain, males growing faster than females and reached the same slaughter weight at
76
Item
CFb Initial weight (kg) Slaughter weight (kg) Feed intake (g per day) Average daily gain (g per day) Feed conversion rate (g gÿ1) Ultrasound fat thickness (mm) Ultrasound LMA (cm2) a
Contrasta
Diets
12.89 29.32 1024 329 3.15 3.70 8.55
CM 13.57 29.16 1008 410 2.49 2.80 8.27
BF 12.89 27.90 1002 334 3.02 2.60 7.14
BM 13.46 28.47 1027 395 2.63 2.70 7.78
EBF 12.94 27.78 981 297 3.34 3.10 7.25
EBM 13.37 27.80 1014 380 2.70 2.70 7.03
S.E.M. 0.16 0.27 20.33 0.01 0.04 0.06 0.12
I c
NS 0.068 NS 0.098 NS 0.002 0.001
II
III
IV
V
NS NS NS 0.034 0.039 NS NS
0.094 NS NS 0.001 0.001 0.003 NS
NS NS NS NS NS 0.011 NS
NS NS NS NS NS NS NS
Contrast I: control vs. betaine; Contrast II: betaine vs. rumen escape betaine; Contrast III: female vs. male; Contrast IV: diet vs. sex; Contrast V: diet vs. betaine. CF: control female; CM: control male; BF: betaine female; BM: betaine male; EBF: rumen escape betaine female; EBM: rumen escape betaine male. c NS: not signi®cant (Pr>0.1). b
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Table 2 Effect of dietary betaine administration on growth performance
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
77
less age. The same tendency was observed for feed conversion rate, we found effect of sex (p<0.001; 2.61 versus 3.17 for males and females, respectively) and differences between the two sources of betaine (p<0.05; 2.83 versus 3.02 for B and EB, respectively). Again, no differences were found when the control group was compared with both betaine and rumen escape betaine groups. In a previous study with lambs (FernaÂndez and Gallego, 1996; FernaÂndez, 1998), betaine (2 g kgÿ1) neither affected feed conversion rate as in this trial (Contrast I). This is in agreement with results reported in pigs (Virtanen and Campbell, 1994; Smith et al., 1995), although Cadogan et al. (1993) no effect of betaine was reported on feed intake, average daily gain, and feed conversion rate. Haydon et al. (1995) and Mattews et al. (1998) reported that betaine affects growth performance of pigs, but the effect is variable being in¯uenced by crude protein and net energy content of the diet. Currently, there is a complete lack of information in small ruminants about the role of betaine on growth performance under different dietary levels of energy and protein, although some authors had indicated a positive effect of betaine on protein metabolism (Radcliffe and Egan, 1978; Mitchell et al., 1979; Xue and Snoswell, 1985; Puchala et al., 1995). Table 2 also shows ultrasound FT determined on lambs 24 h prior to slaughter and signi®cant differences were found. Lower (p<0.01) FT was found for betaine than control diet (2.8 versus 3.3 mm as average, respectively), and for males than females (2.7 versus 3.1 mm, respectively), but no signi®cant difference was found between betaine and rumen escape betaine. The interaction between diet and sex was also signi®cant (p<0.05) indicating that betaine reduced FT in females (2.6 for BF versus 3.7 and 3.1 mm for CF and EBF, respectively) and no effect was found in males (2.7 mm as average). However, rumen escape betaine did not promote any signi®cant effect, indicating that only unprotected betaine had a positive effect in reducing the subcutaneous fat at the 12th and13th rib level in female lambs but not in males. In the study of FernaÂndez (1998) lambs fed the diet enriched in betaine reduced FT 0.5 mm and no effect of sex was observed. These results are in agreement with previous ®ndings in pigs in which betaine signi®cantly reduced P2 fat thickness (p<0.05; Virtanen and Campbell, 1994). The reduction of backfat in pigs with P2 values around 20 mm was estimated to be 2±2.5 mm when betaine was supplemented at the rate of 1±2 g kgÿ1, which represents a proportional similar reduction to that we observed in the studies with lambs. The same tendency were reported in gilts by Cadogan et al. (1993) and Smith et al. (1995), but not by Haydon et al. (1995). Despite that, chicks given a diet with 0.6 g kgÿ1 betaine had a lower body fat concentration than those given diets enriched in methionine and choline (Saunderson and Mackinlay, 1990). In order to study in more detail the effect of diet and sex during growth, the evolution over time of ultrasonic determination of FT and LMA were made. These results are shown in Figs. 1 and 2, respectively. Using repeated measurement analysis of variance, a signi®cant effect of time (p<0.001) over treatments for FT were found. The effect of sex (p<0.001) and diet (p<0.05) were signi®cant, and interaction between treatments and time was observed (p<0.01). Time had a linear effect (p<0.001) on FT deposition in treatments CF, CM, EBF and EBM, and a quadratic effect (p<0.01) in treatments BF and BM. Therefore, betaine treatment seems to slow down fat deposition or lipid mobilization during later stages of growth, both in males and females. However, male lambs had
78
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Fig. 1. Effect of betaine inclusion into the diet and sex on the evolution of FT measured by ultrasound in growing lambs from weaning to slaughter (28.40.7 kg).
similar subcutaneous FT deposition independently if betaine is added to the diet or not. Lipid deposition in females was different, and reduction of FT was observed in lambs added betaine when compared with control and rumen escape betaine. According to this data, it seems that betaine reduced subcutaneous FT in animals that have more capacity for lipid deposition, similar to observations for chicks and pigs (Saunderson and Mackinlay, 1990; Virtanen and Campbell, 1994). This is in agreement with the results shown in Tables 2 and 3 (effect of source of betaine on carcass characteristics), where more FT, perirenal fat, external carcass fat score and internal kidneys fat score were found in females than males. Males reached slaughter LW 12 days before than females, on average, and no effect of betaine was found (Figs. 1 and 2). However, more time was
Fig. 2. Effect of betaine inclusion into the diet and sex on the evolution of LMA measured by ultrasound in growing lambs from weaning to slaughter (28.40.7 kg).
Item
CFb Hot carcass weight (kg) Cold carcass weight (kg) Dressing percentage (%) EUROP classi®cationd External carcass fat score (1±5)d Internal kidneys fat score (1±3)d Carcass fat thickness (mm) Carcass LMA (cm2) Perirenal fat (g) Intramuscular content of lipids (g 100 gÿ1) a
Contrasta
Diets
15.63 15.27 53.30 R 2 2 3.50 9.97 401.67 3.43
CM 14.61 14.22 50.07 R 2ÿ 2ÿ 2.00 10.45 220.00 2.51
BF 14.62 14.24 52.39 R 2 2 2.80 10.01 396.00 2.95
BM 14.27 13.80 50.08 R 2ÿ 2ÿ 2.00 10.52 245.50 3.28
EBF 14.50 14.16 52.23 R 2 2 3.70 9.83 405.00 3.01
EBM 13.86 13.50 49.88 R 2ÿ 2ÿ 2.30 10.11 217.00 2.74
S.E.M. 0.15 0.14 0.17 0.06 0.05 0.04 0.09 0.25 11.44 0.22
I 0.013 0.010 NS NS NS NS NS NS NS NS
II c
NS NS NS NS NS NS 0.006 0.059 NS NS
III
IV
V
0.025 0.015 0.001 0.016 0.003 0.001 0.001 0.017 0.001 NS
NS NS NS NS NS NS NS NS NS 0.050
NS NS NS NS NS NS NS NS NS 0.001
Contrast I: control vs. betaine; Contrast II: betaine vs. rumen escape betaine; Contrast III: female vs. male; Contrast IV: diet vs. sex; Contrast V: diet vs. betaine. CF: control female; CM: control male; BF: betaine female; BM: betaine male; EBF: rumen escape betaine female; EBM: rumen escape betaine male. c NS: not signi®cant (Pr>0.1). d Converted to numeric values for statistical analysis. b
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Table 3 Effect of dietary betaine administration on carcass characteristics
79
80
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
taken for females to reach slaughter LW, and therefore, more deposition of lipid was observed. It seems that anhydrous betaine is more effective in promoting lipid mobilization or distribution when the animal has more capacity to synthesize lipid tissue. Fig. 2 shows an effect of time over LMA by treatment. Treatment did not in¯uence LMA but the effect of time was signi®cant (p<0.001). By means of orthogonal polynomials contrast we observed a quadratic effect of time over LMA (p<0.05) but no differences in the slopes for treatments were observed. 3.2. Carcass characteristics The effect of betaine on carcass characteristics is shown in Table 3. Signi®cant differences (p<0.05) were found for hot and cold carcass weight. These differences could be due to control diets on which lambs had slightly greater slaughter weights than on betaine diets (29.24 versus 27.99 kg, respectively). No signi®cant differences among diets were found for dressing percentage (average 51.33%). However, signi®cant differences were found for the effect of sex (Contrast III), females having greater values of dressing percentage than males (p<0.001; 52.64 versus 50.01%, respectively). Other reports in the literature have indicated that betaine does not affect carcass traits in pigs (Smith et al., 1994; Cera and Schinckel, 1995), and our data are in agreement with these observations, with the exception of those reported by Mattews et al. (1998) where betaine increased dressing percentage. We did not ®nd signi®cant differences among diets in the conformation of the carcasses according to the EUROP scale. All carcasses were classi®ed as R with the exception of BF and EBF that were R (good), males having slightly better conformation that females (p<0.05; in Contrast III). In a previous study with lambs, FernaÂndez et al. (1998b) did not ®nd signi®cant differences for diets added betaine (2 g kgÿ1) or between sex. The EUROP classi®cation obtained was Rÿ but slaughtering weight was slightly lower (25.9 kg LW) than in the present trial (28.4 kg LW). External carcass fat, internal kidney fat score and perirenal fat (Table 3) were affected by sex (p<0.01) but not by betaine source. Females record higher classi®cation (2) and perirenal fat (401 g) than males (2ÿand 228 g), indicating the greater fatness of females than males. In the study by FernaÂndez et al. (1998b), they did not ®nd signi®cant differences for betaine and sex in external carcass fat, with an average classi®cation of 2, but internal kidney fat was affected (p<0.01) by betaine (2ÿ versus 2; betaine and control, respectively). Although redistribution or decrease fat deposition in pigs have been reported (Virtanen and Campbell, 1994), we have been unable to ®nd in the literature references to a positive effect of betaine on subjective carcass conformation or external fat score. Saunderson and Mackinlay (1990) have shown that betaine decreased fat of chicks. Treated chickens were heavier but leaner compared to control group chickens, and breast meat yield of the betaine group was 3.7% higher than control group. The present results also need to be viewed in context of the inherent protein and fat deposition potential of the lambs involved. Subcutaneous FT and LMA at the 12th and 13th rib level obtained on the carcass 24 h after slaughter are shown in Table 3. No signi®cant differences were observed for control versus betaine diets (Contrast I), although signi®cant differences were obtained (p<0.01
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
81
and p<0.05 for carcass FT and LMA, respectively) between sources of betaine (Contrast II). Thus, carcass FT was lower for betaine than rumen escape betaine (2.37 versus 3.03 mm, respectively) and LMA followed the opposite tendency (10.27 versus 9.97 cm2 for betaine and rumen escape betaine, respectively). Campbell et al. (1995), using betaine supplementation at 1.25 kg tÿ1 in pigs, observed a reduction of 2.0±2.5 mm of FT at P2 level and an increase of LMA of 2 cm2. However, Horcas et al. (1998) working with lambs did not report any reduction in lipid deposition when betaine was added to the ®nishing diets (3 mm as average). In order to evaluate if the reduction of FT was only in subcutaneous tissues or it affected other parts of the carcass, intramuscular content of lipids in longissimus muscle was measured. Intramuscular content of lipids is shown in Table 3 and neither the effect of diet nor that of sex was observed. In a previous study, FernaÂndez et al. (1998a) observed a lower concentration of intramuscular fat content in lambs fed on diets enriched in betaine compared to those fed a basal diet (2.58 versus 4.46 g 100 gÿ1), being the effect independent of sex. In this study interaction was observed and females had greater intramuscular contents of lipids for C and EB than males, but the opposite tendency was observed for B, where males had greater values than females (3.28 versus 2.95 g 100 gÿ1, respectively). There were means interactions between diet and sex (p<0.05), diet and betaine (p<0.001) indicating a reduction of intramuscular lipids in females fed with betaine. This may be due to the relative late deposition of intramuscular fat (Koohmaraie et al., 1995), the period when betaine seems to be more effective in lowering lipid accumulation. However, some compounds with methyl donor properties interact with fat metabolism (Percival et al., 1970) which suggest that the activity of some enzymes involved in lipid metabolism might also be involved. So, while reduction of subcutaneous fat may be considered as a positive effect of betaine, the reduction of intramuscular lipids needs further investigation. In summary, the effect of source of betaine on growth performance and carcass characteristics was variable. Results from this experiment indicate that dietary supplementation with rumen escape betaine had no effect on growth performance and carcass fatness in both males and females. Neither anhydrous betaine affected males but it promoted lower subcutaneous FT and fatness in females, probably due to the greater potential for response at higher rate of lipid deposition. Acknowledgements This work was partially supported by a Technology Contract with Trouw Nutrition EspanÄa S.A. References AOAC, 1995. Of®cial Methods of Analysis, 16th Edition. Association of Of®cial Analytical Chemists, Washington, DC. Cadogan, D.J., Campbell, R.G., Harrison, D., Edwards, A.C., 1993. The effects of betaine on the growth performance and carcass characteristics of female pigs. In: Batterham, E.S. (Ed.), Manipulating Pig Production. Australasian Pig Science Association, Attwood, Victoria, Australia, p. 219.
82
C. FernaÂndez et al. / Animal Feed Science and Technology 86 (2000) 71±82
Campbell, R.G., Cadogan, D.J., Morley, W.C., Uusitalo, R., Virtanen, E., 1995. Interrelationships between dietary methionine and betaine on the growth performance of pigs from 65 to 100 kg. J. Anim. Sci. 73 (Suppl. 1), 82 (Abstract). Cera, K,R., Schinckel, A.P., 1995. Carcass and performance responses to feeding betaine in pigs. J. Anim. Sci. 73 (Suppl. 1), 82 (Abstract). Colomer-Rocher, F., Delfa, R., Sierra, I., 1986. Cuadernos INIA (1988). 17, 19±41. FernaÂndez, C., 1998. UtilizacioÂn de bioproductos en la nutricioÂn de pequenÄos rumiantes; betaina en corderos. 1. Congreso Nordestino de ProduccioÂn Animal, Vol. 3. VII Simposium Nordestino de AlimentacioÂn de Rumiantes, SNPA, Fortaleza, Brazil, pp. 27±34. FernaÂndez, C., Gallego, L., 1996. Efecto de la betaõÂna sobre los rendimientos productivos y el nivel de engrasamiento en corderos de raza Manchega. XXI Jornadas Cientõ®cas de la SEOC, LogronÄo, EspanÄa, pp. 281±289. FernaÂndez, C., Gallego, L., LoÂpez-Bote, C.J., 1998a. Effect of betaine on fat content in growing lambs. Anim. Feed Sci. Technol. 73, 329±338. FernaÂndez, C., Gallego, L., Molina, A., de la Fuente, J.M., 1998. The effect of betaine on subcutaneous fat thickness. EAAP Publication No. 90, 446±450. Haydon, K.D., Campbell, R.G., Prince, T.J., 1995. Effect of dietary betaine additions and amino:calorie ratio on performance and carcass traits of ®nishing pigs. J. Anim. Sci. 73 (Suppl. 1), 83 (Abstract). Horcas, E., Cuartielles, M.I., Lahera, L.M., Delfa, R., 1998. UtilizacioÂn de betaõÂna en pienso de corderos al ®nalizar el cebo como factor retardador del engrasamiento. XXIII Jornadas Cientõ®cas de la SEOC, 95±97. INRA, 1988. In: Jarrige, G. (Ed.), Alimentation des Bovins, Ovins et Caprins. INRA, Paris, France, 476 pp. Koohmaraie, M., Shackelford, S.D., Wheeler, T.L., Lonergan, S.M., Doumit, M.E., 1995. A muscle hypertrophy condition in lamb (callipyge) Ð characterization of effects on muscle growth and meat quality traits. J. Anim. Sci. 73, 3596±3607. Lawrence, B.V., Schinckel, A.P., Adeola, O., Cera, K., 1995. Performance of pigs fed betaine from 60 to 110 kg body weight. J. Anim. Sci. 73 (Suppl. 1), 195. Marmer, W.N., Maxwell, R.J., 1981. Dry column method for the quantitative extraction and simultaneous class separation of lipids from muscle tissue. Lipids 16, 365±371. Mattews, J.O., Southern, L.L., Pontif, J.E., Higbie, A.D., Bidner, T.D., 1998. Interactive effects of betaine, crude protein, and net energy in ®nishing pigs. J. Anim. Sci. 76, 2444±2455. Mitchell, A.D., Chappell, A., Knox, K.L., 1979. Metabolism of betaine in the ruminant. J. Anim. Sci. 49, 764±774. National Research Council, 1985. Guide for the Care and Use of Laboratory Animals. Publication No. 85-23, NIH, Washington, DC. Percival, G.S., Dunn, S.H., Howe, J.M., Clark, H.E., 1970. Interaction between methionine, fat and choline in the growing rat. J. Nutr. 100, 664±670. Puchala, R., Sahlu, T., Herselman, M.J., Davis, J.J., 1995. In¯uence of betaine on blood metabolites on alpine and angora kids. Small Rum. Res. 18, 137±143. Radcliffe, B.C., Egan, A.R., 1978. The effect of diet and of methionine loading on activity of enzymes in the transulfuration pathway in sheep. Aust. J. Biol. Sci. 31, 105±114. SAS, 1988. SAS/STAT User's Guide, Release 6.03 Edition. SAS Institute Inc., Cary, NC, 1028 pp. Saunderson, C.L., Mackinlay, J., 1990. Changes in body weight, composition and hepatic enzyme activities in response to dietary methionine, betaine and choline levels in growing chicks. Br. J. Nutr. 63, 339±349. Smith, J.W., Owen, K.Q., Nelssen, J.L., Goodband, M.D., Tokach, M.D., Friesen, K.G., Lohrmann, T.L., Blum, S.A., 1994. The effects of dietary carnitine, betaine and chromium nicotinate supplementation on growth and carcass characteristics in growing ®nishing pigs. J. Anim. Sci. 72 (Suppl. 1), 274 (Abstract). Smith, J.W., Nelssen, J.L., Goodband, M.D., Tokach, M.D., Richert, B.T., Owen, K.Q., Bergstrom, J.R., Blum, S.A., 1995. The effects of supplementing growing ®nishing swine diets with betaine and (or) choline on growth and carcass characteristics. J. Anim. Sci. 73 (Suppl. 1), 83 (Abstract). Virtanen, E., Campbell, R., 1994. Reduzierung der Ruckenspeckdicke durch Einsatz von Betain bei Mastchweinen. Handbuch der tierischen Veredlung, Vol. 19. Verlag H. Kamlage, Onsnabruek, Deutschland, pp. 145±150. Xue, G.P., Snoswell, A.M., 1985. Regulation of methyl group metabolism in lactating ewes. Biochem. Int. 11, 381±385.