Effects of Partial Replacement of Conventional with Alternative Feeds on Nutrient Intake, Digestibility, Milk Yield and Composition of Awassi Ewes and Lambs

The role of olive leaves and saccharomyces cerevisiae supplementation in enhancing the performance and economic feasibility of fattening lambs

Objectives were to assess the use of olive leaves (OL) to replace wheat straw, the forage source, and the supplementation of Saccharomyces cerevisiae (SC) on nutritional intake, growth performance, blood parameters, and carcass quality in lambs. A total of twenty-one newly weaned Awassi lambs, weighing an average of 19 ± 0.6 kg, were randomly distributed to three groups. These three diets were: CON: 0% OL control diet; OL diet of 25%; and OL plus 0.4 g SC/head/d (OLSC) diet of 25% of dietary dry matter (DM). The first seven days were devoted to adaptation and the next sixty days were devoted to gathering data. Daily records of nutrient intake were made. On the 49th day of data collection, four animals were randomly selected from each group and kept in individual metabolism cages (1.0 × 0.8 m) with slatted mash for eight days (four days for data collection and four days for cage adaptation) to evaluate N balance and nutrient digestibility. All lambs were slaughtered after the study to assess the quality of the meat and the carcass features. No difference in DM consumption (P > 0.05) between the treatment groups. When OL-containing diets were compared to the CON diet, the consumption of acid detergent fiber and neutral detergent fiber (NDF) was lower (P ≤ 0.0002), whereas metabolizable energy and ether extract were higher (P < 0.0001). While the OL diet was intermediate, the final BW, total gain, and average daily gain for the OLSC diet tended to be higher (P < 0.087) than the CON diet. Lambs fed the OL-containing diets had a lower (P = 0.0020) cost of growth ($US/kg) than lambs in the CON group. All other nutrient digestibilities were comparable between the treatment diets, except NDF digestibility, which was greater (P = 0.045) in the OLSC group than in the CON group. The N balance variables showed a similarity between the various diets (P > 0.05). Lambs fed the OLSC diet tended to have higher weights (P ≤ 0.098) for fasting live weight, hot carcass weight, carcass cuts weights, and cold carcass weight than lambs on the CON diet. The OLSC diet resulted in higher (P < 0.025) loin weight and intermuscular fat in comparison to the CON and OL diets. No difference (P ≥ 0.05) in the dissected tissues between diets. The longissimus dorsi muscle's dimensions and physicochemical characteristics did not alter (P > 0.05) across the treatment diets. In comparison to the CON and OL diets, the OLSC diet resulted in higher serum glucose levels (P = 0.044). Nonetheless, there were similarities (P ≥ 0.05) in various serum blood parameters between the treatment diets. In conclusion, using OL or/and supplemented SC is positively associated with nutrient intake, growth performance, some carcass parameters, and loin cut tissue, and the most effective aspect is decreasing production cost ($US/kg gain), which makes it a good solution to pass inflation feedstuff prices and cover animal needs.

Polymorphisms at Candidate Genes for Fat Content and Fatty Acids Composition: Effects on Sheep Milk Production and Fatty Acid Profile Using Two Dietary Supplementations

The nutritional value of sheep's milk and its derivatives is influenced by the lipid fraction, which is affected by diet and genetics. This study aimed to explore the genetic variations in the DGAT1 and SCD genes and assessed the impact of the DGAT1 genotype on milk quality in Valle del Belìce sheep, considering diet supplementation with carob pulp and barley grain. Among the potentially polymorphic sites, only DGAT1 g.127 C > A and SCD g.87 C > A showed variability. The DGAT1 genotype did not significantly impact milk yield and composition, except for higher urea content in the CA genotypes than in the CC ones. Carob pulp increased the milk fat content compared to barley grain. Genetic variation in DGAT1 was associated with changes in the milk fatty acid profile; specifically, the CA genotype exhibited higher levels of short-chain fatty acids and lower levels of polyunsaturated fatty acids compared to the CC genotype. Carob pulp supplementation increased saturated fatty acids and reduced unsaturated fractions, leading to milk with higher atherogenic and thrombogenic indices. No significant interaction was found between genotype and diet. This study provides insights into the genetic and dietary factors influencing sheep's milk composition. Further research is needed to understand the impact of these genetic variations on milk production and composition, as well as to determine optimal levels of carob pulp for improving fat percentage and promoting sustainable sheep breeding practices.

Effects of dietary inclusion of dry distillers grains with solubles on performance, carcass characteristics, and nitrogen metabolism in meat sheep: a meta-analysis

We conducted a meta-analysis in this scientific study to determine the effects of feeding meat sheep dry distillers grains with solubles (DDGS). Thirty-three peer-reviewed articles that met our inclusion requirements and were published between 1997 and 2021 were examined. To calculate the variation in performance, fermentation, carcass features, and nitrogen efficiency between the DDGS and control (no DDGS) treatments, we used 940 sheep weighing an average of 29.1 ± 1.5 kg. We used a hierarchical mixed model to conduct a meta-regression, subset, and dose-response analysis, while taking into consideration categorical variables like breed (pure or cross-breed), and continuous factors, like CP, NDF, and DDGS inclusion rate. Our findings indicate that sheep fed DDGS had higher (p < 0.05) final body weight (51.4 vs. 50.4 kg), neutral detergent fiber digestibility (55.9 vs. 53.8%), and total-tract ether extract digestibility (81.7 vs. 78.7%) than sheep on a control diet. No effects were observed on DMI, CP, and rumen fermentation, but dietary DDGS tended to increase (p = 0.07) HC weight (25.53 vs. 24.6 kg) and meat (redness) color (16.6 vs. 16.3) among treatment comparisons. Dietary DDGS was associated with higher N intake (29.9 vs. 26.8 g/d), fecal N (8.2 vs. 7.8 g/d), and digestibility (71.9 vs. 68.5%). Urinary nitrogen was significantly (p < 0.05) affected linearly by increasing the intake of DDGS in the diet. Based on the dose-response analysis, dietary DDGS inclusion should not exceed 20% to avoid negative effects on performance, nitrogen metabolism, and meat color. Dietary protein from DDGS should not exceed 17% to prevent reduced TVFA concentrations. Breed strongly influenced (p < 0.05) RMD in performance, and inconsistent responses were observed between crossbreed and purebred sheep comparisons. Despite these inconsistencies, no publication bias was observed, but a high variance (Ω²) among comparisons-between-studies was detected. This meta-analysis showed evidence in support of the hypothesis that feeding meat sheep DDGS at a rate of 20% can improve their performance, digestibility, carcass weight, and meat color.

Feeding of faba beans (Vicia faba L.) enhances the growth performance of lambs

Background and Aim:

The high price of conventional diet ingredients led livestock producers to search for alternative feed sources such as faba beans (Vicia faba L.; FB). This study aimed to evaluate the effect of feeding FB on the growth performance of lambs.

Materials and Methods:

A total of 24 male lambs were distributed randomly into two groups and fed a control diet (CON; n=12) and 200 g/kg FB (FB200; n=12) dietary dry matter (DM). The study lasted for 70 days. The first 7 days were used for acclimatization, followed by 63 days of data collection (i.e., nutrient intake and digestibility and growth performance). A complete randomized design was used for the statistical analysis.

Results:

The average initial body weight (BW) (20.54±0.798 kg) was similar between the diet treatment groups. Lambs fed the FB200 diet demonstrated higher (p≤0.008) nutrient intake than lambs fed the CON diet. The FB200 diet tended to improve the digestibility of DM, crude protein, and acid detergent fiber more than the CON diet (p≤0.072). Neutral detergent fiber and ether extract digestibility were higher (p<0.05) in lambs fed the FB200 diet than those fed the CON diet. Next, nitrogen retention increased (p<0.05) in lambs fed the FB200 diet compared with the CON diet. Final BW did not differ (p=0.221) between the two groups. However, the average daily gain was higher (p=0.028) in lambs fed the FB200 diet than in lambs fed the CON diet. Furthermore, the cost of gain decreased more (p=0.04) with the FB200 diet than with the CON diet.

Conclusion:

The results obtained in this study demonstrate the feasibility of using FB in feeding growing lambs, as it was shown to improve growth performance and reduce the cost of diet and gain.

Application of Olive By-Products in Livestock with Emphasis on Small Ruminants: Implications on Rumen Function, Growth Performance, Milk and Meat Quality

The olive oil industry has a leading position in the Mediterranean countries, resulting in the production of considerable quantities of the respective by-products (OB) that constitute an important environmental issue. OB contain valuable nutrients and bioactive components that can be re-used under the bioeconomy strategy, and several chemical, physical, and biological processes have been evaluated with the intention to improve their nutritional value. One feasible application of OB is their incorporation in the diets of livestock and especially ruminants due to their high fiber content. As indicated by numerous studies, OB dietary supplementation increases the levels of monounsaturated fatty acids (MUFAs) and decreases that of saturated fatty acids (SFAs) in the milk and meat of ruminants with beneficial effects for consumers' health. At the same time, environmental impact and feeding costs are reduced without detrimental effects on ruminal fermentation, nutrients utilization, growth performance, carcass traits, milk yield and composition.

The Inclusion of Black Cumin Meal Improves Growth Performance of Growing Awassi Lambs

Twenty-four Awassi lambs were randomly divided into two dietary treatments to assess the influence of black cumin meal (BCM; Nigella sativa L.) feeding on growth performance. Diets were no BCM (CON) or 150 g BCM/kg DM (BCM150)). Lambs were fed the experimental diets for 80 days. Lambs were housed randomly in individual pens that were fitted with water and feed containers. During the study, nutrient intake was measured daily. Body weight (BW) and average daily gain (ADG) were evaluated biweekly. Nutrient digestibility and nitrogen (N) balance were evaluated on days 49-59. Intakes of dry matter, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE) and metabolizable energy were greater (p ≤ 0.05) in the BCM150 diet than in the CON diet. The digestibility of DM, CP and EE (p ≤ 0.04) was improved in the BCM150 diet compared to the CON diet. However, NDF and ADF digestibility did not differ between the two diets. Nitrogen retained (g/d; p = 0.01) and N retention (%; p = 0.05) was greater in the BCM150 compared with CON diet. Final BW, ADG, and feed efficiency (DM intake: kg of gain) was greater (p ≤ 0.002) in BCM150 lambs than the CON lambs. However, cost/kg of BW gain was lower in the BCM150 diet than in the CON diet. In conclusion, the inclusion of black cumin meal improved the growth performance and profits in diets of growing lambs. Therefore, it could be used as an alternative to soybean meal and barley as a protein and energy supplement, respectively.

Growth Performance and Carcass Traits Responses to Dried Distillers' Grain with Solubles Feeding of Growing Awassi Ram Lambs

Simple Summary

Corn grain is considered to be the most important crop in the world. Corn dried distiller grains with solubles is a by-product of ethanol production. It is included at 0, 125, or 25 g/kg in lambs’ diets. This inclusion reduced the cost of diet, indicating the good possibility of using it in small ruminant diets.

Abstract

This study considers the impact of dried distillers’ grain with solubles (DDGS) in diets of lambs. Randomly; 27 lambs were distributed to one of three diets. Diets were: a control diet (CON; n = 9), a 125 (DDGS125; n = 9) or a 250 g/kg DDGS (DDGS250; n = 9) of dietary dry matter (DM). The lambs were fed using these diets for 91 days. To assess carcass traits; five lambs were randomly selected at the end of the study. No significant differences were detected in intake and digestibility of DM; crude protein and fiber. Average daily gain did not differ among diets. Carcass characteristics did not differ among diets. With the exception of shear force and redness, which were greater in DDGS250 than in DDGS125 and CON diets, meat quality parameters were unaffected. Eye muscle area decreased in DDGS125 than in DDGS250 and CON diet. These results demonstrate that the feeding of lambs on DDGS at 125 or 250 g/kg DM did not have any impact on growth. These diets only had a simple effect on the characteristics of carcass and meat quality. These results suggest that it would be suitable to introduce these feeds into sheep nutrition in the future.