Dietary Supplementation of Yeast Culture Into Pelleted Total Mixed Rations Improves the Growth Performance of Fattening Lambs

Abstract

There is a growing interest in the use of yeast (Saccharomyces cerevisiae) culture (YC) for the enhancement of growth performance and general animal health. Grain-based pelleted total mixed rations (TMR) are emerging in intensive sheep farming systems, but it is uncertain if the process of pelleting results in YC becoming ineffective. This study aimed to examine the effects of YC supplemented to pelleted TMR at two proportions of corn in the diet on animal performance, feed digestion, blood parameters, rumen fermentation, and microbial community in fattening lambs. A 2 × 2 factorial design was adopted with two experimental factors and two levels in each factor, resulting in four treatments: (1) low proportion of corn in the diet (LC; 350 g corn/kg diet) without YC, (2) LC with YC (5 g/kg diet), (3) high proportion of corn in the diet (HC; 600 g corn/kg diet) without YC, and (4) HC with YC. Fifty-six 3-month-old male F2 hybrids of thin-tailed sheep and Northeast fine-wool sheep with a liveweight of 19.9 ± 2.7 kg were randomly assigned to the four treatment groups with an equal number of animals in each group. The results showed that live yeast cells could not survive during pelleting, and thus, any biological effects of the YC were the result of feeding dead yeast and the metabolites of yeast fermentation rather than live yeast cells. The supplementation of YC resulted in 31.1 g/day more average daily gain regardless of the proportion of corn in the diet with unchanged feed intake during the 56-day growth measurement period. The digestibility of neutral detergent fibre and acid detergent fibre was increased, but the digestibility of dry matter, organic matter, and crude protein was not affected by YC. The supplementation of YC altered the rumen bacterial population and species, but the most abundant phyla Bacteroidetes, Firmicutes, and Proteobacteria remained unchanged. This study indicates that YC products can be supplemented to pelleted TMR for improved lamb growth performance, although live yeast cells are inactive after pelleting. The improved performance could be attributed to improved fibre digestibility.

Modulation of rumen bacterial community and feed utilization in camel and sheep using combined supplementation of live yeast and microalgae

“…This phylum was dominated by Christensenellaceae_R-7_group, Butyrivibrio, Ruminococcus , Saccharofermentans , Anaerovorax , Succiniclasticum (Table 8 ; Fig. 2 ), which agree with previous studies 7 , 63 , 68 – 71 . Christensenellaceae _R-7_group was also found in the rumen of goats and Yak and has a potential role in cellulose degradation 69 , 72 .…”

“…1 , 2 ). Similar findings were obtained by Song et al 63 who investigated the effect of yeast supplementation in the diet of lambs on rumen microbiota. Limited information is available about the effect of the microalgae Spirulina and Chlorella on rumen microbiota, and few studies quantified some of rumen bacterial genera using qPCR and concluded that algae supplementation affected the copy number of those genera, which supports our results 28 , 66 , 67 .…”

“…The concentration of acetic was declined and propionate was increased in sheep, which was also indicated in previous studies 48 , 51 , 53 . Song et al 63 included the yeast culture in the diet of growing lambs and observed that rumen pH and total VFA were not affected; rumen ammonia and butyric acid were increased, and acetic acid was decreased. Previous studies 54 , 57 revealed that fiber degradation stimulates acetic acid production, which could demonstrate higher acetic acid in supplemented camel group (TC).…”

“…Limited information is available about the effect of the microalgae Spirulina and Chlorella on rumen microbiota, and few studies quantified some of rumen bacterial genera using qPCR and concluded that algae supplementation affected the copy number of those genera, which supports our results 28 , 66 , 67 . The majority of phylum Bacteriodetes was assigned to genus Prevotella and RC9_gut_group, reflecting the importance of these genera in rumen fermentation 63 . Genus Prevotella is involved in the degradation of different substrates in the rumen, including protein, xylan, pectin, and starch, and can produce propionate 6 , 7 , which might demonstrate the positive correlation between genus Prevotella, propionic acid, and CPD (Fig.…”

Growth Performance, Rumen Fermentation and Inflammatory Response on Holstein Growing Cattle Treated with Low and High Non-Fibrous Carbohydrate to Neutral Detergent Fiber Ratio Pelleted Total Mixed Ration

“…The pelleting procedure encompasses steam heating and mechanical strain to break complex fiber constituents and boost starch gelatinization, increasing nutrient digestibility and feed slaking [8]. In comparison with the loose TMR, pelleted TMR has been regarded as an expeditious feed form for ameliorating the digestibility and reducing animal diet sorting, which was a practicable strategy to raise fattening ruminants under the intensive feedlot feeding mode [9]. However, roughage ingredients need to be dried and rough pulverized before they can be used in pelleted TMR.…”