The growth hormone gene polymorphism and its relationship to performance and carcass features in Egyptian Awassi lambs

The main purpose of the existing experiment was to assess the allelic and genotypic polymorphisms of the Growth hormone (GH) gene and its correlation with growth indices, efficiency of consumed feed, some body indices and carcass traits of the Egyptian Awassi sheep. Forty Egyptian Awassi male lambs were selected for their growing indices (post-weaning daily gain, marketing weight, and weaning weight), feed efficiency (consumed feed and of consumed feed), body conformational indicators (skeletal muscle index, relative body index, body mass index, and body index), and carcass features (dressing %, hot carcass weight, fore-legs %, neck %, loin %, ribs %, abdominal fat %, Tail % and hind-legs %). The polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP) tool was applied to detect the genotypic and allelic GH gene polymorphisms properties. The PCR-RFLP analysis identified three main genotypes (AA, AB and BB) and two main alleles (A and B). The GH genotype (AA or AB) exhibited moderate significant influence (P < 0.05) on marketing weight, Loin% and Tail%. Also, genotype (AB or BB) of expressed GH gene significantly (P < 0.01) influence on consumed feed, post-weaning daily gain, neck% and body mass index, whereas, it had no influence on the phenotypic values of the other characteristics investigated. The presence of the A allele in the genotype was markedly associated (P < 0.01) with consumed feed, body mass index and post-weaning daily growth; conversely, the presence of the B allele in the genotype was significantly related (P < 0.05) with marketing weight, loin %, and tail %. While, GH gene expression was revealed to be highly significant (P < 0.01) in relation to post-weaning daily growth, feed intake, and neck %. According to the findings, determining the associations between GH gene variation and growth, efficiency of consumed feed, body measurements, and carcass features of Egyptian Awassi sheep and applying marker assisted selection with the GH gene to improve these traits is warranted and will be of significant economic value to sheep production.

Effect of feeding pomegranate seed pulp on Awassi lambs' nutrient digestibility, growth performance, and carcass quality

Background and Aim

The use of alternative feeds in feeding livestock as an alternative to traditional feeds has been used for many years, on the one hand, to lower the price of feed and, on the other hand, to raise the profitability of raising livestock. The study aimed to investigate the effect of feeding pomegranate seed pulp (PSP) on the growth performance and carcass characteristics and the health of Awassi lambs.

Materials and Methods

Twenty-four male lambs (16.9 ± 0.42 kg) were assigned randomly to one of two isonitrogenous (160 g/kg crude protein of dietary dry matter [DM]) treatment diets. The diets were the control (CON) and PSP-containing diet (100 g/kg of dietary DM; PSP100). The experimental period was 70 days preceded by 7 days of adaptation to diets. Feed intake was measured and lambs were weighed on day one and then biweekly. On day 49, eight lambs (four lambs per treatment) were chosen randomly and placed in metabolic cages for a digestibility trial. At the end of the trial, lambs were slaughtered to evaluate carcass characteristics and meat quality. The data were analyzed using Proc Mixed procedures of SAS.

Results

The results revealed that nutrient intake was greater (p < 0.05) in lambs fed PSP100 than those fed the CON diet. Nitrogen intake and nitrogen retention were greater (p < 0.05) for lambs who consumed the PSP100 diet compared to CON. Final weight, total gain, and average daily gain were greater (p < 0.05) with lambs fed PSP100. Hot and cold carcass weights were higher (p < 0.05) by the PSP100 group than by the CON group. Carcass cut weight increased (p < 0.05) with feeding PSP100 diet. No differences were detected in blood parameters except high-density lipoprotein content, which was greater (p < 0.05) in the PSP100 group compared with the CON group.

Conclusion

It could be concluded that adding PSP to lambs' diets improved growth and carcass measurements positively and did not negatively affect lambs' health; therefore, it is recommended to use PSP as an alternative to traditional feeds in lambs formulated rations.

Effects of Different Levels of Yucca Supplementation on Growth Rates, Metabolic Profiles, Fecal Odor Emissions, and Carcass Traits of Growing Lambs

Sixty male Awassi lambs were used to investigate the effects of dietary Yucca schidgera extract (YS) on the production, fecal and urinary odor emissions, and carcass traits of growing lambs fed complete pellets. Lambs were fed either a complete pelleted diet without yucca (control) or supplemented with 300 or 600 mg YS/kg dry matter (DM) during the 84-day experiment. The weights and feed consumption of the lambs were measured weekly. Blood samples were taken on days 1, 28, 58, and 84, and ruminal fluid samples were collected on day 70. On day 90, the odor emissions from feces and urine were measured. On day 84, 12 lambs were slaughtered for the evaluation of carcass and meat quality. The final values for bodyweight, bodyweight gain, and feed efficiency of lambs fed the YS₃₀₀ diet were 3.40%, 6.64%, and 6.17%, respectively, higher (p < 0.05) than those fed the YS₆₀₀ diet. Additionally, the percentage of dressing, myofibril fragmentation index, and ruminal isovalerate percentage of lambs treated with YS₆₀₀ were higher than those treated with YS₃₀₀. Compared with the control, the addition of yucca reduced odor emissions from feces and urine. In conclusion, dietary YS₃₀₀ had no additional benefits on growth rate, feed efficiency, and carcass traits, while dietary YS₆₀₀ improved fecal and urinary odors.

Impacts of substituting soybean meal with cold extraction sesame meal on growth accomplishment and health in growing Awassi lambs

Blood metabolites and growing performing were evaluated in lambs (15.7 ± 0.33 kg; initial body weight) fed diets containing either soybean meal or cold extraction sesame meal (SM). The design of the study was a complete randomized design. Twenty-two lambs were divided into two diets, 0% SM (CON) or 12.5% SM (SM12.5) of dietary dry matter (DM), raised for 84 days (7 and 77 days for adaptation and data collection, respectively) and fed ad libitum diets (crude protein (CP) content 15.6% DM). Parameters that were measured included nutrient intake, average daily gain (ADG), digestibility, N balance, and blood parameters. Excluding ether extract (EE) and metabolizable energy intake which were greater (P ≤ 0.05) in the SM12.5 group versus the CON group, no differences in other nutrient intakes were detected (P ≥ 0.05) between the two diets. Lambs fed the SM12.5 diet had more digestibility for DM, CP, neutral detergent fiber, and EE. Nitrogen in feces was lower (P ≤ 0.05) in the SM12.5 group versus the CON group. However, retained N (g/day) increased (P ≤ 0.05) in the SM12.5 group versus the CON group. Final body weight and ADG improved (P ≤ 0.05) in the SM12.5 diet. Cost per kilogram of gain diminished (P ≤ 0.05) in the SM12.5 than the CON diet. Blood glucose increased while creatinine decreased (P ≤ 0.05) in lambs that consumed SM12.5. Results obtained herein proved that replacing soybean meal with sesame meal improved growth performance while reducing the cost of gain in addition to not affecting health negatively.

The impact of lamb diets containing either barley or corn on growth performance and carcass quality

BACKGROUND AND AIM

Grains, such as barley (BAR) and corn (CORN), are major energy sources for small ruminants. This study aimed to assess the impact of feeding either BAR or CORN-based diets on growth performance and carcass characteristics.

MATERIALS AND METHODS

Awassi male lambs, average body weight of 20.4±0.49 kg, were chosen randomly. Lambs were acclimated for 10 days and assigned to one of two diets (1) BAR and (2) CORN. Feeding continued for 70 days with 60 days of data collection. Daily intake was recorded. Measurements of body weight were taken starting from day 1 then once per week throughout the study period. On day 40, six lambs were randomly chosen from each group and placed in metabolism cages to assess digestibility and N balance. Lambs were slaughtered on the last day of the study to evaluate carcass characteristics and meat quality.

RESULTS

Neutral and acid detergent fiber and ether extract intake were greater (p≤0.05) for lambs fed the BAR diets. Nitrogen loss in feces tended to be greater (p=0.09) for the CORN diet. Eye muscle depth (mm) tended to be greater (p=0.07) for the BAR diet. Nutrient digestibility, daily weight gain, carcass characteristics, and meat quality were not different (p≥0.1) between diets.

CONCLUSION

The results herein demonstrate that feeding BAR grain improved nutrient intake efficiency and consistency and did not affect weight gain and carcass traits. BAR-based diets might be a useful alternative to CORN for feeding growing lambs.

The inclusion of black cumin meal improves the carcass characteristics of growing Awassi lambs

Background and Aim:

Black cumin meal (BCM) is the principal by-product that can be obtained from black cumin seed (Nigella sativa L) after the oil is removed from the fruit and represents 70-75% of the fruit weight. The aim of this experiment was to assess the influence of feeding BCM on the carcass characteristics and meat quality of growing lambs.

Materials and Methods:

Twenty-four Awassi lambs were randomly divided into two dietary treatments. The lambs were penned individually in single pens and provided access to ad libitum feed and water. The dietary treatments were no BCM (control [CON]; n=12) or 150 g BCM/kg (BCM 150; n=12) of dietary dry matter.

Results:

Lambs fed BCM had greater (p≤0.01) fasting live BW, and hot and cold carcass weights. Leg fat and eye muscle depth were lower (p≤0.05) in CON versus BCM lambs. Meat whiteness (L*), redness (a*), and yellowness did not differ between lambs fed the two diets.

Conclusion:

The inclusion of BCM improves lamb carcass characteristics, but does not affect lamb meat quality.

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.

Dietary inclusion of alternative feedstuffs had no negative effects on hematological and biochemical parameters of growing Awassi lambs

Dietary inclusion of alternative feedstuffs (AF) could impact animal performance, ruminal ecosystem, and/or blood parameters. The objective of the current trial was to evaluate the effects of dietary inclusion of mixed AF on hematological and biochemical parameters of growing lambs. Male Awassi lambs (n = 27, average BW = 20.0 ± 0.5 kg and average age of 90 days) were randomly assigned to one of three dietary groups (9 lambs/group). Diets were formulated to contain (on DM basis) 0 (CTL; conventional diet without AF), 25% (25AF), or 50% (50AF) of mixed AF (dry bread, carob pods, olive cake, and sesame meal). Blood samples were collected from each lamb before morning feeding at the beginning (7 days after the start), middle (day 35), and end (68 day) of the study. Hematological parameters were not affected (P ≥ 0.11) by treatment diets. Except for urea N and cortisol, dietary treatments had no significant (P ≥ 0.07) effects on serum levels of all of the measured metabolites and enzymes. Lambs fed the 50AF diet had the lowest blood level of urea N and cortisol. The current study demonstrates that dietary inclusion of AF up to 50% did not negatively impact lambs' health assessed with changes in hematological and biochemical parameters.

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.

Polymorphism of prolactin, growth differentiation factor 9, and calpastatin genes and their effects on weight traits in Awassi lambs

OBJECTIVES

This study was conducted to determine the correlation among prolactin gene (PRG), growth differentiation factor 9 (GDF-9), and calpastatin (CAG) genes polymorphism with growth traits in Awassi lambs.

MATERIALS AND METHODS

Records of 779 Awassi lambs from 264 dams and 15 sires were used. The sex, type of birth (single versus twins), weight at birth, average daily gain (ADG), and the adjusted weight at 60 days of age were determined for each animal. Blood samples were collected from all lambs to determine PRG, GDF-9, and CAG polymorphism using polymerase chain reaction-Restriction fragment length polymorphism.

RESULTS

Three PRG genotypes (AA, AB, and BB) were determined with a frequency of 0.88, 0.05, and 0.07, respectively. The frequency of each allele was 0.84 and 0.16 for A and B alleles, respectively. For GDF-9, there were only two genotypes detected (AB and BB) with a frequency of 0.96 and 0.04, respectively. The frequency of each allele was 0.92 and 0.08 for A and B alleles, respectively. For CAG, two genotypes were also detected (AB and BB) with a frequency of 0.92 and 0.08, respectively. The frequency of each allele was 0.96 and 0.04 for A and B alleles, respectively. A significant (p ≤ 0.04) effect of PRG genotype on birth weight was detected but this effect was not significant on ADG and weight at weaning. There were no associations between any of the pre-weaning growth traits and GDF-9 and CAG variants.

CONCLUSION

The results of this study show that PRG could be used to select dams with a high frequency of dystocia to reduce birth weight of newborn lambs and therefore conserve the dam's reproductive functions and improve lamb survivability.