Influence of diet supplementation with yeast culture (Saccharomyces cerevisiae) on performance of Zaraibi goats

Small Ruminant Research 52 (2004) 223–229

Influence of diet supplementation with yeast culture (Saccharomyces cerevisiae) on performance of Zaraibi goats A.A. Abd El-Ghani∗ Department of Animal Production, Faculty of Agriculture, Minia University, Minia 61111, Egypt Received 8 January 2003; received in revised form 5 June 2003; accepted 23 June 2003

Abstract This study was conducted to evaluate the effect of supplementing different levels of yeast culture (YC) in Zaraibi goats’ diets on digestibility, milk yield and composition, rumen activity and performance of Zaraibi goats during the lactation period. Fifteen Zaraibi does in the first and second lactation, 12–24 months of age, and weighing in average 32.50 kg were randomly divided into three equal groups. The control group (T1) was fed a concentrate mixture and roughage (alfalfa and wheat straw), while the second (T2) and third (T3) groups were fed the same diet supplemented with 3 or 6 g of YC, respectively. In the digestibility trials, results revealed that bucks fed YC had higher nutrient digestion coefficients than the control group. A similar trend was observed in feed intake. Treatment had a higher effect (P < 0.05) at 3 h post-feeding on pH for bucks fed YC than in the control group. Bucks fed YC had lower ruminal ammonia values (P < 0.05) at 3 and 6 h post-feeding than the control group. Ruminal VFA were higher (P < 0.05) for bucks fed YC at 6 h post-feeding than in the control group. The lactating Zaraibi goats had higher (P < 0.05) milk yield, and contents of milk energy, protein, total solid and solid nonfat than the control goats. It is concluded that the inclusion of 6 g per day of YC in goat’s diets is recommended under field conditions. © 2003 Elsevier B.V. All rights reserved. Keywords: Goats; Yeast; Digestibility; Rumen parameters

1. Introduction Goat numbers around the world have increased around 50% during the last 20 years. Presently research on goats is less developed than on cattle and sheep inspite of the worldwide importance of goats farming. Generally the quality and efficiency of goats research is highly variable although in the last 20 years, the situation has improved (Morand-Fehr et al., 2002). Studies of diet supplementation with yeast culture (YC) (Saccharomyces cerevisiae) to lactating animals was initiated by Adams et al. (1981) and ∗ Tel.: +20-106598256; fax: +20-86342601. E-mail address: [email protected] (A.A. Abd El-Ghani).

Harrison et al. (1988). Yeast culture is considered a non-hormonal growth promoter that showed a positive response in milk yield and composition in dairy animals (Sune, 1998; Garg et al., 2000). Reklewska et al. (2000) reported that goats fed 2 g of yeast culture per head daily had a significantly higher milk yield. Their milk protein content increased in relation to the initial level more (P < 0.01) than in goats fed the standard diet. Similar improvements of digestibility, weight gain and feed conversion have been reported by El-Waziry et al. (2000), Kholif et al. (2000), Martins et al. (2000) and Fayed (2001). During late pregnancy and early lactation, dairy goats are under great physical, psychosocial and metabolic stresses which are reflected in altered

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hormone profiles, increased disease and disorder susceptibility (e.g. mastitis, ketosis, etc.) and possibly reduced production and reproduction. There are few reports concerning the effect of using yeast culture on goats. Therefore, the present work was conducted to study the effect of supplementing different levels of yeast culture in goats’ diets on their milk yield, composition and performance of Zaraibi goats during lactation period. Three digestibility trials were to be done at the end of the feeding trials on three Zaraibi bucks to evaluate nutrient digestion coefficients of the experimental diets and rumen activity. 2. Materials and methods 2.1. Location This work was carried out at the Experimental and Research Center, Minia University, located at Shosha, Samalout, Minia, Egypt. The experiment lasted for 180 days and the animals were housed in semi-open shade. Average of air temperature (AT, ◦ C) and relative humidity (RH, %) were 35.1 ◦ C and 24.5% at day time, while 31.5 ◦ C and 32.5% at night time, respectively. 2.2. Digestibility trials Three digestibility trials in a crossover-design were done on three Zaraibi bucks (average 34.7 kg of BW) using metabolism cages to evaluate nutrient digestion coefficients of experimental diets. Each experimental period consisted of a 7 days preliminary period and 5 days to determine ad libitum feed intake and subsequently bucks were fed at 90% of ad libitum for another 5 days for quantitative collections of feces. Fresh water was available all day. Samples of 10% from feces were daily subsampled separately, combined over each period and stored at −20 ◦ C until laboratory analysis. 2.3. Rumen fluid samples At the end of each digestibility experiment, rumen fluid samples were collected from Zaraibi bucks using a rubber stomach tube. Samples were taken

before feeding, 3 and 6 h post-feeding. Ruminal pH was immediately measured using an E 512 type pH meter (Mecrohm Herisau, Switzerland). Rumen fluid samples were strained through 4 layers of cheesecloth and kept frozen for later analysis. Ammonia N was determined according to the Conway method (1962), and the samples for VFA were assayed according to Warner (1964). 2.4. Lactation trial Fifteen lactating Zaraibi does in the first and second season of lactation, 12–24 months of age and weighing an average 32.50 kg, were randomly divided into three groups of six goats each. The experiment started 1 month post-kidding and continued for 5 months. All animals were fed according to NRC (1981). The control group (T1) was fed a concentrate mixture (60%) and (40%) roughage (alfalfa and wheat straw), while the second (T2) and third (T3) groups were fed the same diet supplemented with 3 or 6 g of YC, respectively. Chemical analysis of the experimental feedstuffs is given in Table 1. Feeding requirements were adjusted biweekly according to weight changes and milk production. The animals were weighed biweekly and milk production was estimated individually once a week throughout the lactation period using the kid suckling technique as reported by Ashmawy (1980) and Ruvuna et al. (1988). Feed conversion was expressed as DM, TDN or DCP required per kg of milk. The animals were treated for internal and external parasites prior to the trials. Animals were given injections of vitamin mixtures consisting of Vitamin A, D and E (1.5 ml contained 55,000 IU Vitamin A, 25,000 IU Vitamin D3 and 25 mg Vitamin E). Water was available all the time in the pens. 2.5. Chemical analysis Feedstuffs and feces samples were dried at 70 ◦ C for 24 h and then ground to pass a 1 mm screen. The DM, N, ether extract, crude fiber and ash were determined according to AOAC (1980). The NFE and OM were calculated by difference. Representative milk samples about 1% of total milk produced were taken once biweekly from each goat in the morning and evening on the same day. Samples were combined and analyzed for TS, fat, protein,

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225

Table 1 Chemical composition of feedstuffs (DM basis) used for experimental rations Items Concentrate feed Alfalfa Wheat straw Yeast culture

mixturea

DM (%)

OM (%)

CP (%)

EE (%)

CF (%)

NFE (%)

ASH (%)

89.05 14.96 88.11 91.60

88.41 85.10 86.11 92.65

15.64 12.80 3.26 45.88

3.92 2.30 1.42 4.40

12.36 23.36 36.01 3.57

56.58 46.64 45.42 38.80

11.59 14.9 13.89 7.35

a Concentrate feed mixture consists of: 30% yellow maize, 25% wheat bran, 22% decorticated cotton seed cake, 20% rice bran, 1.5% ground limestone, 1.5% common salt.

SNF and ash according to AOAC (1980), while lactose were calculated by difference. Milk energy was calculated according to the Kirchgessner equation (1982), while FCM was calculated according to the equation of Reafat and Saleh (1962). 2.6. Statistical analysis Data of these studies were statistically analyzed using General Linear Model (SAS, 1990). Duncan Multiple Range Test was used to test the significant differences between treatment means (Duncan, 1955).

3. Results and discussion 3.1. Digestion coefficients Digestion coefficients and feed intake of experimental rations fed to bucks are shown in Table 2. Results revealed that bucks fed YC had higher nutrient digestion coefficients than the control group. Digestion coefficients of CF, EE and NFE were higher (P < 0.05 or P < 0.01) for bucks fed YC than for controls while the differences for digestion coefficients of DM, OM and CP were not significant. El-Waziry et al. (2000) reported that N degradability was slightly increased by

Table 2 Digestion coefficients, feed intake of experimental rations fed to Zaraibi bucks Items

T1

T2

T3

±S.E.

Significance

Body weight (kg)

35.47

34.29

34.58

1.68

NS

Digestion coefficients DM OM CF CP EE NFE

65.84 71.65 61.32b 69.67 61.47b 71.25b

66.24 72.21 65.24a 72.41 63.40a 71.87b

64.24 72.14 66.21a 70.91 62.10ab 73.85a

1.22 1.25 1.10 1.13 0.21 0.19

NS NS

685b 19.3b 47.1b 425.90b 12.01b 29.31c 60.08b 1.70b 4.28b

765ab 22.3ab 53.9ab 490.20ab 14.30a 34.59b 71.00a 2.08a 5.01a

Feed intake DM intake (g per day) g/kg BW g/kg BW0.75 TDN (g per day) g/kg BW g/kg BW0.75 DCP (g per day) g/kg BW g/kg BW0.75

787a 22.7a 55.2a 514.45a 14.88a 36.08a 72.80a 2.11a 5.12a

15.3 0.86 1.54 0.29 0.13 0.14 0.17 0.06 0.04

∗∗

NS ∗

∗∗

∗∗ ∗ ∗ ∗∗ ∗ ∗ ∗∗ ∗ ∗

The letters a, b, c means in the same columns with different letters are different (P < 0.05). NS: nonsignificant, T1: control ration, T2 = 3 g (YC) yeast culture supplementation per day, T3 = 6 g (YC) yeast culture supplementation per day. ∗ P < 0.05. ∗∗ P < 0.01.

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the addition of yeast. The improvement of digestion coefficients may be attributed to increase in the number of rumen cellulolytic bacteria due to yeast supplementation (Williams, 1989; Gomez-Alarcon et al., 1990). These results are in agreement with Allam et al. (2001) and Fayed (2001) who reported that digestibility coefficients of all nutrients of goats fed YC were higher than in control animals. A similar trend was observed with feed intake (Table 2) as DM, TDN and DCP (g per day, g/kg BW or kg BW0.75 ) for bucks fed YC 3 or 6 g per day were higher (P < 0.05 and P < 0.01) than in the control group. However, bucks fed 3 or 6 g YC had higher feed intake (1.12 and 1.15% times that of the control group). This may be due to the yeast, which provides stimulatory factors to rumen cellulolytic bacteria (Wholt et al., 1998; Chaucheyras-Durand and Fonty, 2002). Putnam and Schwab (1994) illustrated the mode of action of yeast culture (Fig. 1) by stimulating rumen microbes, which improved fiber digestion and consequently increased feed intake. These results are in agreement with those reported by Gado et al. (1998) who reported that YC supplementation improved (P < 0.05) nutritive value in the diets of goats. 3.2. Rumen fluid parameters Rumen fluid parameters for bucks that were fed experimental rations are shown in Table 3. Bucks fed YC had higher pH values (P < 0.05) at 3 h post-feeding than the control group. Bucks fed YC had lower (P < 0.05) ruminal ammonia values at 3 and 6 h post-feeding than the control group. Ruminal VFA were significantly higher for bucks fed YC at 6 h

Decreased Ammonia

Yeast culture .

post-feeding than for the control group. However, the values of VFA were significantly different between treatments before feeding (at 0 time), which may be attributed to differences between animals or to other factors like saliva that affecting these values or to residual effects of treatments. Enjalbert et al. (1999) reported that supplementation of YC (0.5% DM) significantly decreased rumen ammonia from 148.5 to 103.1 mg l−1 , 3 h post-feeding, and significantly increased by about 20% the concentration of VFA. However, Kamra et al. (2002) showed that production of VFA remained unaffected, but NH3-N decreased (P < 0.05) and pH increased (P < 0.05) in rumen liquor of the YC group. The physicochemical and fermentative parameters were altered in the rumen of goats, that had received yeast, suggesting more efficient fermentation processes (Chaucheyras-Durand and Fonty, 2002). El-Waziry et al. (2000) reported that concentrations of ammonia N were decreased and VFA concentrations were increased with yeast supplementation. Results in the present study are in agreement with Putnam and Schwab (1994) who illustrated the mode of action of yeast culture (Fig. 1). Alshaikh et al. (2002) reported that rumen ammonia N concentration decreased significantly after yeast culture supplementation. On the other hand time of sampling on ruminal parameters (Table 3) had no significant effect on pH values. In contrast, time of sampling had a significant effect (P < 0.05 and <0.01) on ruminal ammonia and VFA concentration. Ruminal ammonia concentrations increased at 3 h then decreased at 6 h post-feeding, while VFA increased at 6 h post-feeding. Koul et al. (1998) explained that the effect of YC on rumen

Altered microbial protein synthesis Altered AA profile of Duodenal digesta

St imulating Improved fiber digestion of rumen microbes

Moderate pH

Increased protein passage

Increased intake

Production response

Altered VFA Production

Decreased lactic acid concentration Decreased methane production

Fig. 1. Mode of action of yeast culture (Putnam and Schwab, 1994).

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Table 3 Least square means (±S.E) of rumen fluid parameters for Zaraibi bucks fed experimental rations Items

Time

Treatments T1

pH

0 3 6

Between treatments T2

6.80 6.40B 6.35

T3

6.89 6.47AB 6.25

6.85 6.55A 6.30

±S.E.

Significance

0.05 0.03 0.02

NS ∗

NS

±S.E. and significance between times

±S.E. Significant

0.40 NS

0.46 NS

0.30 NS

– –

– –

Ammonia-N, mg/100 ml

0 3 6

16.54c 24.34Aa 22.47Ab

15.87b 21.68Ba 20.57Ba

16.87b 22.04Ba 20.21Ba

0.66 0.47 0.34

NS

±S.E. and significance between times

±S.E. Significant

∗

– –

– –

VFA, meq./100 ml

0 3 6

7.89Bc 9.52b 11.11Ba

0.02 0.08 0.03

NS

±S.E Significant

∗∗

– –

– –

±S.E and significance between times

1.11

1.05

0.43

1.16

∗∗

∗

8.00ABc 9.20b 12.02Aa

8.54Ac 9.90b 12.32Aa

0.49

∗∗

0.51

∗∗

∗ ∗

∗ ∗

The letters A, B, C means in the same columns and (a, b, c) rows with different letters are significantly different. NS: nonsignificant, T1: control ration, T2 = 3 g (YC) yeast culture supplementation per day, T3 = 6 g (YC) yeast culture supplementation per day. ∗ P < 0.05. ∗∗ P < 0.01.

fermentation was maximum up to 2–4 h after feeding and then it decreased with time.

12.2 or 17.4% higher for goats fed YC 3 or 6 g per day, respectively, than the control group. Milk energy was 3.17, 3.52 and 3.71%, TS were 12.87, 12.40 and 12.57%, SNF was 8.65, 8.33 and 8.26% for goats fed the control diet or 3 or 6 g YC per day, respectively. The increase of milk may be attributed to yeast supplementation, which may act as a source of B-beneficial vitamins. The present results are in agreement with those reported by Iwanska et al. (1999), Kholif et al. (2000) and Alshaikh et al. (2002).

3.3. Milk production parameters of lactating does Milk production parameters of lactating does are presented in Table 4. Results revealed that treatment had an effect (P < 0.05) on milk yield and contents of milk energy, protein, TS and SNF. Milk yield was

Table 4 Least square means (±S.E) of milk yield and composition for Zaraibi does fed different experimental rations supplemented with yeast Items

Milk yield (kg per day)

Milk energy (MJ/kg)

Fat (%)

Protein (%)

Lactose (%)

Ash (%)

Total solids (%)

Solid non-fat (%)

T1 T2 T3

0.980b 1.100a 1.150a

3.17b 3.52a 3.71a

4.22b 4.15c 4.27a

3.15a 3.05ab 2.98b

4.85 4.52 4.65

0.65 0.68 0.67

12.87a 12.40b 12.57b

8.65a 8.33b 8.26b

±S.E. Significance

0.01

0.06

0.02

0.03

0.18 NS

0.41 NS

∗

0.12

0.10

∗

∗

∗

∗

∗

The letters a, b, c means in the same columns with different letters are different. NS: nonsignificant, T1: control ration, T2 = 3 g (YC ) yeast culture supplementation per day, T3 = 6 g (YC) yeast culture supplementation per day. ∗ P < 0.05.

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Table 5 Feed intake and feed conversion of lactating Zaraibi does fed experimental rations Items

T1

T2

T3

±S.E.

FCMa

690.2c 1090b 710b 99.8

774.5b 1210a 850a 105

819.25a 1250a 910a 116

11.14 11.12 10.05 8.25

(7% yield g per day) DM intake (g per day) TDN intake (g per day) DCP intake (g per day) Feed kg kg kg

conversion DM/kg milk TDN/kg milk DCP/kg milk

1.11 0.72b 0.10

1.10 0.77a 0.09

1.08 0.79a 0.10

0.01 0.02 0.001

Significance ∗ ∗∗ ∗

NS NS ∗

NS

The letters a, b, c means in the same columns with different letters are significantly different. NS: nonsignificant, T1: control ration, T2 = 3 g YC, T3 = 6 g YC. a FCM: fat corrected milk. ∗ P < 0.05. ∗∗ P < 0.01.

Goats fed rations supplied with YC 6 g per day (T3) tended to have a higher value of milk fat than controls (T1) or goats fed YC 3 g per day, the difference was significance (P < 0.05). Data of Table 4 showed that lactose decreased with increasing yeast supplementation to 6 g per day YC. These results are in agreement with previous reports by Higginbotham et al. (1994), Sharma et al. (1998) and Allam et al. (2001). Percentages of protein, TS and SNF were decreased as yeast supplementation increased. These finding are in a harmony with reports by El-Badawi et al. (1998) who reported that total solids and protein contents were lower (P < 0.05) in YC-fed goats groups. 3.4. Feed intake and feed conversion of lactating does Feed intake and feed conversion of lactating does fed experimental rations are illustrated in Table 5. Results showed that yeast supplementation increased (P < 0.05 and <0.01) feed intake for does expressed as DM or TDN g per day. Our results are in good agreement with Putnam and Schwab (1994) who illustrated the mode of action of yeast culture (Fig. 1). They reported that yeast supplementation is stimulating rumen microbes, which improved fiber digestion and consequently increased intake. Also increased feed intake by bucks in the digestibility trial or by does in the feeding trial is explained by increased digestibility coefficients of nutrients (Table 2). No significant differences were observed among groups

in feed conversion expressed as kg DM/kg milk or kg DCP/kg milk. These results are in agreement with those previous reported by Castro et al. (2002).

4. Conclusion It is concluded that YC supplementation of lactating Zaraibi goat’s diets had a beneficial effect on productive performance, and the daily inclusion of YC in diets up to 6 g is recommended under field conditions. Further research is necessary to evaluate the mode of action and effects of S. cerevisiae supplementation in diets of goats. References Adams, D.D., Galyean, H.E., Kiesling, J.D., Wallace, M.L., Finkner, M.D., 1981. Influence of viable yeast culture, sodium bicarbonate and monensin on liquid rate, rumen fermentation and feedlot performance of growing steers and digestibility in lambs. J. Anim. Sci. 53, 780–789. Allam, M., El-Shazly, K., Borhami, B.E.A., Mohamed, M.A., 2001. Effect of baker’s yeast (Saccharomyces cerevisiae) supplementation on digestion in sheep and milk response in dairy cows. Egypt. J. Nutr. Feeds 4 (Special Issue), 315–323. Alshaikh, M.A., Alsiadi, M.Y., Zahran, S.M., Mogawer, H.H., Aalshowime, T.A., 2002. Effect of feeding yeast culture from different sources on the performance of lactating Holstein cows in Saudi Arabia. Asian Aust. J. Anim. Sci. 15, 352–356. Ashmawy, B.M., 1980. Comparison of three techniques for the estimation of the milk production of small ruminants. Egypt. J. Anim. Prod. 20, 11–16.

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