A study on the genetic and phenotypic factors affecting specific ewe productivity traits in Sangsari sheep.

The study's objectives were to assess the genetic parameters of reproductive characteristics in Sangsari sheep. A data set of reproductive information with pedigree details from 1995 to 2016 was used. Studied traits were litter size at birth (LSB), litter size at weaning (LSW), litter mean weight per lamb born (LMWLB), litter mean weight per lamb weaned (LMWLW), total litter weight at birth (TLWB) and total litter weight at weaning (TLWW). Test significance of the environmental factors to be included in the model was conducted using the general linear model procedure of the SAS program. All traits were significantly affected by the year of lambing and ewe age at lambing (P < 0.01). The AI-REML procedure of the Wombat program was used to evaluate genetic parameters. A series of bivariate animal models were employed to calculate genetic (rg) and phenotypic (rp) correlations between traits. The total least square means ± standard error of LSB and LSW were 1.04 ± 0.05 and 0.96 ± 0.03, while LMWLB, LMWLW, TLWB, and TLWW were 3.12 ± 0.08, 15.40 ± 0.13, 3.28 ± 0.04, and 19.31 ± 0.16 kg, respectively. The estimates of h2 were relatively low (P < 0.01) and ranged from 0.063 ± 0.028 for LSW to 0.181 ± 0.063 for TLWW. Repeatability estimates varied from 0.101 for LSW to 0.241 for TLWW. The sire service effects for LMWLB, TLWB, and TLWW were 0.012 ± 0.004, 0.023 ± 0.006, and 0.039 ± 0.009, respectively. The traits studied showed a greater magnitude of genetic correlation than phenotypic correlation, with values ranging from - 0.59 (LSB-LMWLB) to 0.87 (LMWLB-TLWB). It appears that focusing on TLWW for selection could result in more significant improvements in the reproductive performance of Sangsari ewes.

Performance, ruminal and fecal microbiome of lambs fed diets supplemented with probiotics.

The present study aimed to investigate the impact of adding two doses of a commercial probiotic on productive performance, ruminal and fecal microbiome in growing lambs. Forty-two Texel or Ile de France crossbred lambs aged 86.9 ± 8.0 days (body weight: 27.4 ± 3.7 kg) were distributed into three groups: basal diet without probiotic supplementation (CG); basal diet + 1 g/animal/day of probiotic (GP1) and basal diet + 5 g/animal/day of probiotic (GP5). The experimental period was 84 days. The weight was evaluated weekly and dry matter intake (DMI) and leftovers were measured daily. At the end of the experiment, lambs were slaughtered. Feces and rumen fluid were collected for microbiome analysis and rumen fragments for histological evaluation. The use of probiotics did not affect weight gain, but GP1 showed a higher silage and DMI intake than CG (p < 0.001). The CG had a greater thickness of keratinized epithelium and stratum corneum (< 0.001) than GP1 and GP5, and greater total papilla width (p = 0.039) than GP1. There was no difference in the general abundance in the rumen and fecal microbiomes. GP5 had a higher proportion of Azoarcus and Dialister taxa in the rumen fluid (p = 0.012 and p = 0.017, respectively) and higher proportion of Treponema and Fibrobacter taxa in the fecal microbiome (p = 0.015 and p = 0.026, respectively), whereas CG had a higher proportion of Anaeroplasma than the other groups (p = 0.032). These results demonstrated the benefits of probiotics for ruminal epithelium protection and microbial diversity. However, there was no effect on performance parameters.

Detection of putative loci affecting milk yield in Turkish Awassi sheep using microsatellite markers.

On the basis of comparisons between bovine and ovine genome mapping information, the aim of the study was to analyze the genetic diversity of selected DNA microsatellites from the bovine genome and to investigate their correlation with the average daily milk yield in Awassi sheep. 18 informative microsatellite markers were selected from the significant QTL regions affecting milk yield identified in the bovine genome in previous studies. The selected microsatellite markers were then amplified by PCR as reciprocal amplifications on the genomic DNA of Awassi sheep, with standard daily milk yield records. Thus, in this study, 18 microsatellite markers associated with milk yield in the bovine genome were examined for both determination of genetic polymorphism within the flock and the effects of marker loci on average daily milk yield in Awassi sheep. Allele frequencies of markers were determined based on the results of fragment analysis. The analysis of variance showed that the 123 bp allele at the marker locus BMS1341 on BTA2 significantly influenced the average daily milk yield of Ivesi sheep (P < 0.01). On the other hand, the BMS381 locus with a 115 bp allele on BTA2, the MCM140 locus with a 185 bp allele on BTA6, the BMS2721 locus with a 155 bp allele, the BM1237 locus with 174 and 180 bp alleles on BTA7, and finally, the BMS1967 locus with a 117 bp allele, the BM4208 locus with 176 and 182 bp alleles, and the INRA locus with a185 bp allele on BTA8 showed moderately significant effects on the average daily milk yield of Ivesi ewes (P < 0.05).

The effect of Vachellia eriolaba leaf meal inclusion on growth performance, blood parameters and methane gas emission in lambs fed diets containing ammoniated maize stover.

The study evaluated the effect of Vachellia erioloba leaf meal in diets containing ammoniated maize stove on growth performance, methane emission and heath of growing lambs. Thirty-two female lambs were allocated to the following four dietary treatments: total mixed ration (TMR, control), 20% inclusion of untreated maize stover (UMS), 20% inclusion of ammoniated maize stover (AMS), and combined inclusion of 10% ammoniated maize stover and 10% Vachellia erioloba leaves (AMSVL). Each treatment was replicated 8 times and a lamb in an individual pen was regarded as an experimental unit in a completely randomized design. Feed intake was higher (P < 0.05) in lambs fed the AMS and AMSVL diets compared to those fed UMS. Final body weights were higher in lambs fed the AMS and AMSVL diets. Both average daily gain (ADG) and feed convention ratio (FCR) were not affected by diet. In comparison with the AMS and AMSVL diets, the lambs fed the UMS diet had the highest (P < 0.05) methane emission. Overall, lambs fed the control diets had the lowest (P < 0.05) methane gas emission. Blood hematological values were affected by diet with the AMSVL fed lambs having the highest (P < 0.05) mean platelet volume (MPV) and procalcitonin (PCT) values. Furthermore, total albumin, amylase and total bilirubin were the highest (P < 0.05) in lambs fed on the AMSVL diet. Lambs fed on AMS diet had the highest (P < 0.05) serum urea levels. It can be concluded that combined inclusion of ammoniated maize stover and Vachellia leaves improved feed value and lamb performance when compared to the individual inclusion of both UMS and AMS.

First molecular diagnosis of the human pathogen Rickettsia raoultii and other spotted fever group rickettsiae in Sudanese ixodid ticks from domestic ruminants.

BACKGROUND: Rickettsial infections are often neglected and poorly recognized by physicians in many tropical and subtropical regions. Despite a number of recent reports describing rickettsial diseases in new locations and the discovery of new rickettsiae, medical science and research have largely neglected the diagnosis and antimicrobial treatment of rickettsial infections in subtropical and tropical areas; thus, much remains to be discovered. This study aimed to detect and characterize spotted fever group (SFG) rickettsiae in ixodid ticks infesting domestic ruminants in Khartoum State. METHODS: Polymerase chain reaction targeting both genes that encode for citrate synthase (gltA) and outer membrane protein (ompA) was performed for the presence of SFG rickettsia followed by sequence and phylogenetic analysis. RESULTS: Of the 202 ticks examined for the presence of SFG rickettsia, gltA gene was detected in 4 samples (2%). Furthermore, gltA-positive samples were used to amplify the ompA gene, in which only two samples yielded positive results. Sequence and phylogenetic analysis of the positive samples revealed four different species of SFG rickettsiae: Rickettsia aeschlimannii, Rickettsia rhipicephali, Rickettsia massiliae and Rickettsia raoultii. CONCLUSIONS: These results indicated the presence of SFG rickettsia in Sudanese ticks. This also indicates that humans have an opportunity to acquire these infections. It is important to keep in mind the need for careful consideration of rickettsial infections in individuals with a fever of unknown origin.

Estimating genetic parameters and trends in growth curve traits of Zandi sheep using the SAEM algorithm.

The objectives of this study were to evaluate the influence of environmental effects on growth curve traits of Zandi lambs and estimate their genetic parameters with the best-fit animal model. For this purpose, live body weight (BW) records (n = 10,607) of 2,519 individuals (which were progeny of 278 rams and 1,485 ewes) were used to estimate genetic effects on growth curve traits from birth to yearling age of Zandi lambs. Using the Stochastic Approximation Expectation Maximization (SAEM) algorithm the growth curve parameters of five different mixed functions (i.e., Brody, Richards, Von Bertalanffy, Gompertz and Logistic) were obtained, then for the most appropriate model the genetic parameters were estimated using a Bayesian approach fitted multivariate animal model and ignoring or including maternal genetic effect. Except Richards model, all other mixed functions used here closely fitted actual BW records (R2 > 0.96). However, the Logistic function provided the best fit in every type. So, studied growth curve traits were estimated asymptotic weight which considered as mature weight (a), rate parameter (b), rate of maturing (k), and age (Ai)/weight (Wi) at the point of inflection. Of the fixed effects studied (i.e., gender, birth type, dam age, season and year of birth), the only non-significant relationship was the effect dam age on b and Ai. Based on the best-fitted model, posterior means of heritability estimates for a, b, k, Wi and Ai were 0.142 ± 0.036, 0.094 ± 0.029, 0.143 ± 0.063, 0.149 ± 0.039 and 0.029 ± 0.013, respectively. Posterior means of genetic correlations between mentioned traits ranged from -0.018 ± 0.069 (b-k) to 0.959 ± 0.029 (a-b), whereas the phenotypic correlation varied from -0.047 ± 0.014 (b-k) to 0.836 ± 0.007 (a-b). It was concluded that the model including only direct additive effect was sufficient to explain the variation in all investigated growth traits of Zandi lambs, selection for these traits results in slow genetic gain (due to the lack of sufficient genetic variation), but it would not be difficult to improve their mature weight and rate of maturing jointly. The results indicate that although the rate of genetic change for mature weight has been small (0.008 ± 0.003 kg year-1; P < 0.05) but in the favorable direction for this breed.

Effect of replacing Tifton 85 hay with Moringa hay (Moringa oleifera L.) on the nutrient metabolism, metabolic profile, and water balance of sheep.

This study aimed to evaluate the effect of replacing Tifton 85 hay (TH) with Moringa hay (MH) on the intake, apparent digestibility, ingestive behaviour, rumen parameters, serum attributes, nitrogen balance, water balance, and urinary attributes of sheep. Thus, 5 rams, ½ Dorper + ½ Santa Inês, that were 12 ± 4 months of age with an initial body weight of 32.8 ± 2.6 kg were distributed in metabolic cages in a Latin square design. The experiment lasted 85 days and was divided into five 17-day periods. The animals received rations with increasing replacement (0, 100, 200, 300, or 400 g/kg of dry matter in the total diet) of TH for MH. The forage: concentrate ratio of the diets was 40:60. Replacing TH with MH reduced (P < 0.05) the intake of organic matter, crude protein, neutral detergent fibre (NDFap), and total digestible nutrients by sheep. The apparent digestibility of NDFap and the feeding and rumination efficiencies of NDFap were reduced (P < 0.05) when MH replaced TH in the animals' diet. This replacement did not influence (P > 0.05) serum urea, total protein, creatinine, or aspartate aminotransferase in sheep. Replacing TH with MH decreased water intake and excretion (P < 0.05). In addition, nitrogen excretion via urine, urinary creatinine, and nitrogen absorption decreased (P < 0.05) when TH was replaced with MH. However, there was an increase in the sheep's nitrogen retention and urine pH. We recommend replacing 30% TH with MH in the diet of lambs because it does not compromise nutrient metabolism.

Evaluation of performance and estimation of genetic parameters for milk yield and reproductive traits in Awassi and Asaf sheep breeds and crosses in the Palestinian territory.

This study aimed to estimate genetic parameters, including heritability and repeatability, for milk yield and prolificacy in sheep. It included 3682 records from 1837 ewes across various breeds: Awassi, Assaf, and Awassi x Assaf crosses, two Awassi lines: Improved Awassi, AFEC Awassi. The study measured total milk yield (TMY), yield up to 120 days (TMY120), and yield up to 150 days (TMY150), alongside reproductive traits: litter size (LS), number of lambs born alive (NLBA), and lambing interval (LI). The analysis utilized a mixed model and the REML procedure to estimate genetic parameters. Results indicated that litter size (LS) had no significant impact on milk traits, whereas breed, location, ewe parity, and lambing season showed significant effects. Lactation length also significantly influenced TMY. For reproductive traits, treatment was significant for NLBA, with location associated with breed, parity, and season affecting all traits. Heritability estimates for TMY ranged from 0.00 in Awassi x Assaf crosses to 0.11 in Awassi, and for TMY120 and TMY150, from 0.00 in Awassi x Assaf crosses to 0.16 in Awassi. Estimates for LS and NLBA varied similarly. The heritability for LI was 0.03 in Awassi and zero in other breeds and crosses. The findings suggest that in the northern West Bank regions of Nablus and Jenin, Assaf or Awassi x Assaf breeds are preferable. The study underscores the importance of comprehensive performance and pedigree recording for effective sheep farm management.

Effects of drinking saline water on carcass traits and meat quality of growing and mature Blackhead Ogaden sheep and Somali goats.

Water salinity has a significant impact on water quality, posing challenges for livestock production and productivity, particularly in arid regions where climate change affects freshwater availability. This study aimed to determine the effect of drinking saline water on the carcass and meat quality traits of sheep and goats in Ethiopia. A total of 100 males with an average initial body weight of growing (18.17 ± 0.51) and mature (22.22 ± 0.52 kg) Blackhead Ogaden sheep and growing (17.99 ± 0.50) and mature (21.99 ± 0.54) kg) Somali goats were used. The design of the experiment was a three-way factorial RCBD with three-factor combinations (5 treatment levels, 2 species, and 2 age groups).Water treatments were natural water (Lake Basaka water (control), low saline water (L-SW), moderate saline water (M-SW), high saline water (H-SW), and very high saline water (VH-SW); that is, NaCl was added to natural water at concentrations of 7.95, 11.93, 15.90, and 19.88 g TDS/L, respectively. The finding showed that increasing salinity levels in drinking water reduced slaughter body weight (SBW), carcass weight (CW), dressing percentage (DP), rib eye area (RAE), total edible components (TEC), and increased total non-edible components (TNEC) (P < 0.05). Similarly, sheep and mature animals had higher (P < 0.001) SBW, CW, DP, RAE, and TEC than goats and growing animals. Sensory evaluation, shear force, and proximate analysis were affected by water salinity, species, and age groups (P < 0.05). Overall, the study revealed that consuming saline water above 11 g TDS/L affected carcass traits and meat quality in Somali goats and Blackhead Ogaden sheep.

Effects of chickpea grain feeding on the growth and carcass features of growing lambs.

An investigation was conducted to find out how diet formulation of chickpea grains (CHPE) rather than soybean meal and barely grain affected the performance, blood metabolites, carcass, and meat quality features of Awassi lambs. Thirty lambs, with an average age of 73 ± 0.85 days and an initial body weight of 21.0 ± 1.29 kg, were randomly assigned into one of three diets, with 10 lambs per treatment diet. The diets were designed to replace a portion of the barley grain and soybean meal and included no CHPE (CON), 7.5% CHPE (CHPE7.5), and 15% CHPE (CHPE15). Lambs were individually housed, fed every day, and weighed every two weeks to measure performance characteristics over the 60-day study period. Four lambs per treatment were chosen at random on day 42 to participate in an N balance study and assess diet digestibility. All lambs were slaughtered at the termination of the trial period to measure the features of the carcass characteristics and meat quality. As the amount of CHPE included in the diets increased, the cost of diets reduced. As the amount of CHPE in the diets increased, so did the intake of ether extract (EE). The CON group's cost per kilogram of increase was higher (P = 0.017) than that of the CHPE7.5 and CHEP15 groups. The digestibility of EE was higher (P = 0.024) in the CHPE15 diet as opposed to the CHPE7.5 and CON diets. The various treatments did not impact blood metabolites, carcass features, or meat quality. Therefore, the present study suggested that chickpeas might be added to the diets of finishing lambs up to 15% of dry matter.

Optimising Laparoscopic Artificial Insemination in Lohi Sheep: Effects of Timing, Sperm Concentration and Body Condition on Fertility Outcome in Subtropical Climates.

The objective of this study was to determine the optimal timing, sperm concentration, and body condition score (BCS) for laparoscopic artificial insemination (LAI) in the subtropical Lohi sheep breed. In Experiment 1, Lohi ewes (n = 80) were synchronised through progestin-sponges (day 0-day 11), administering PGF2α (d-cloprostenol 75 µg/mL; i.m. @ 75 µg /ewe) on day 09 and eCG (i.m. @ 300 IU/ewe) on day 11. Ewes were divided equally into four groups (n = 20 each) and then LAI was performed at 48 (T48), 60 (T60), 72 (T72) and 96 (T96) hours post-sponge removal using 200 million sperm/insemination. In Experiment 2, ewes (n = 81) were synchronised as in Experiment I. Following synchronisation ewes were divided into four groups, each subjected to LAI employing varying sperm concentrations: 10 (S10; n = 21), 20 (S20; n = 20), 50 (S50; n = 20), or 100 (S100; n = 20) million per insemination. Inseminations were performed within a time window of 48-60 h post-sponge removal, based on the findings from Experiment 1. In both experiments ewes were categorised according to BCS, that is, medium 3 and high > 3. Results of Experiment 1 revealed a quadratic response that ewes inseminated at 60-h post-sponge removal exhibited significantly higher pregnancy and twinning rates (p = 0.02). The results of Experiment 2 revealed that sperm concentration had a quadratic effect, 50 million sperm per insemination resulted in maximal pregnancy rates (p = 0.01). Additionally, ewes with medium BCS (≤ 3) had higher pregnancy rates than high BCS (> 3) ewes. In conclusion, ewes with medium BCS (≤ 3) are ideal candidate for LAI and can be inseminated at 60 h with minimal sperm 50 × 106/dose post-sponge removal to achieve a maximum pregnancy rate.

Estimates of genetic parameters for growth traits in dorper crossbred sheep population.

The study was carried out to estimate genetic and phenotypic parameters for growth traits in Dorper crossbred sheep. The data set consisted of 5717 growth records from 1347 individuals of Dorper 50% crossbred sheep descended from 43 sires and 344 dams born between the years 2012 and 2022 at Debre Birhan Agricultural Research Center sheep research station, Ethiopia. Studied traits were birth weight (WT0), weaning weight (WT3), six months weight (WT6), yearling weight (WT12), average daily gain from birth to weaning (ADG1), average daily gain from weaning to six months (ADG2), average daily gain from six months to yearling (ADG3). The (co)variance components were estimated by fitting six different univariate animal models using Average Information Restricted Maximum Likelihood (AI-REML) procedure. Contrary to the genetic trend, phenotypic performance for all studied traits showed a declining trend over the years. Direct heritability estimates of 0.10 ± 0.06, 0.29 ± 0.09, 0.37 ± 0.10, 0.10 ± 0.09, 0.43 ± 0.15, 0.04 ± 0.05, and 0.14 ± 0.09 were obtained for WT0, WT3, WT6, WT12, ADG1, ADG2 and ADG3, respectively. Genetic correlations among the studied traits ranged from -0.43 (between ADG2 and ADG3) to 0.99 (between WT3 and ADG1). Selection for weaning, six months and pre-weaning average daily gain would be expected to yield good response as these traits were found moderately heritable. Strong to moderate genetic correlation of WT3 with WT6, WT12, and ADG1 suggested that selection based on WT3 would result in improvement of other growth traits due to correlated response.

Optimization of handmade cloning technique in sheep and preliminary investigation of umbilical cord mesenchymal stem cells as donor nuclei.

Handmade cloning (HMC) has a higher yield and is relatively less difficult to operate compared to traditional micromanipulation cloning. Yet, there are few reports on handmade cloning in sheep. Therefore, this study investigates the key nodes such as AC and DC voltage, denucleation method and fusion method in sheep handmade cloning. In addition, it compares the effects of fibroblasts (FC) and umbilical cord mesenchymal stem cells (UC-MSCs) of different states as donors on the development of HMC embryos. Furthermore, the effect of different freezing solutions on the survival rate of frozen blastocysts without zona pellucida was also investigated. The results indicate that an AC voltage of 150 V/cm and a DC voltage of 1800 V/cm significantly enhanced the fusion and blastocyst rates (p < .01). The blastocyst rate achieved with umbilical cord MSCs as nucleus donors was significantly higher (40.3%) than that achieved with fibroblasts and differentiated umbilical cord MSCs (21.5%, 22.5%) (p < .01). The highest survival rate was achieved using 20% DMSO + 20% EG for freezing without zona pellucida. In conclusion, the most efficient and pregnant ovine HMC cloning method using 150 V/cm AC, 1800 V/cm DC, knife-cut denucleation, two-step fusion and the use of UC-MSCs as nucleus donors resulted in the highest overall efficiency and pregnancy after transplantation.

Population structure and selective signature of Kirghiz sheep by Illumina Ovine SNP50 BeadChip.

Objective: By assessing the genetic diversity and associated selective traits of Kirghiz sheep (KIR), we aim to uncover the mechanisms that contribute to sheep's adaptability to the Pamir Plateau environment. Methods: This study utilized Illumina Ovine SNP50 BeadChip data from KIR residing in the Pamir Plateau, Qira Black sheep (QBS) inhabiting the Taklamakan Desert, and commonly introduced breeds including Dorper sheep (DOR), Suffolk sheep (SUF), and Hu sheep (HU). The data was analyzed using principal component analysis, phylogenetic analysis, population admixture analysis, kinship matrix analysis, linkage disequilibrium analysis, and selective signature analysis. We employed four methods for selective signature analysis: fixation index (Fst), cross-population extended homozygosity (XP-EHH), integrated haplotype score (iHS), and nucleotide diversity (Pi). These methods aim to uncover the genetic mechanisms underlying the germplasm resources of Kirghiz sheep, enhance their production traits, and explore their adaptation to challenging environmental conditions. Results: The test results unveiled potential selective signals associated with adaptive traits and growth characteristics in sheep under harsh environmental conditions, and annotated the corresponding genes accordingly. These genes encompass various functionalities such as adaptations associated with plateau, cold, and arid environment (ETAA1, UBE3D, TLE4, NXPH1, MAT2B, PPARGC1A, VEGFA, TBX15 and PLXNA4), wool traits (LMO3, TRPS1, EPHA5), body size traits (PLXNA2, EFNA5), reproductive traits (PPP3CA, PDHA2, NTRK2), and immunity (GATA3). Conclusion: Our study identified candidate genes associated with the production traits and adaptation to the harsh environment of the Pamir Plateau in Kirghiz sheep. These findings provide valuable resources for local sheep breeding programs. The objective of this study is to offer valuable insights for the sustainable development of the Kirghiz sheep industry.

The investigation of SNP in SOCS2 gene and its effect on milk yield, fat, protein, and somatic cell count in Awassi ewes.

BACKGROUND: Livestock farmers face financial losses every year because milk yield and components are severely affected by udder diseases. These udder infections attract the immune response from the host and lead to the influx of neutrophils into milk to fight infection and thus the number of somatic cell count (SCC) is increased. The SCC value of milk could be used as an important indicator in detecting clinical mastitis in dairy animals. Also, the milk yield and milk quality (e.g. fat) are negatively affected by the increased SCC. The SCC is used to estimate the somatic cell score (SCS)of the milk, which is used as an indirect measure to detect subclinical mastitis. Therefore, the purpose of this study was to investigate the presence of a significant SNP rs868996547, on the suppressor of cytokine signaling 2 gene (SOCS2) which is related to milk yield and milk quality in Awassi sheep. METHODS: In this study, milk production data was obtained from 210 healthy Awassi ewes with different parties and ages. The general linear model (GLM) process analysis of variance (ANOVA) was used to determine fixed effects on milk traits. The DNA extraction was done using a blood DNA extraction kit from Qiagen. To validate the presence of SNP a customized SNP detection developed by Thermofisher Scientific was used. The presence of the SNP in the SOCS2 gene was detected with genotypes (C/T, T/T, and C/C) and T being the mutated allele and it had a significant (p < 0.015) effect on the milk yield (p < 0,015;0.091), fat (p < 0,001;0,003), fat/protein ratio (p < 0.001;0,037) and log10SCC value (p < 0,006;0,015) of Awassi ewes. However, the protein, total solid, and lactose percentages in the wild type and the mutated ewes found having no significant difference (P > 0.05). CONCLUSION: Our result showed the increase in SCC or SCS of the milk significantly affected the milk yield and composition. Parity and age had significant effects on ewes' milk yield (p < 0.001). In conclusion, we investigated the presence of SOCS2 gene of Awassi ewes in the study flock and its effect on milk yield, fat, and somatic cell count, and the change in milk composition and milk yield because of SCC.

The use of infrared thermography as an indicator of methane production in hair sheep.

Infrared thermography may be an alternative technology for measuring the amount of CH4 produced and has the advantages of low cost, speed and efficiency in obtaining results. The study's objective was to determine if the infrared thermography is adequate for predicting the emission of CH4 in hair sheep and the best time after feeding to carry out the measurement. Twelve Santa Inês lambs (females, non-pregnant, with twelve months old and mean body weight of 39.3 ± 2.1 kg) remained for two days in respirometric chambers, in a semi-closed system, to determine the CH4 production. The animals were divided into two treatments, according to the diet provided. During this period, seven thermographic photographs were taken, at times - 1 h, -0.5 h, 0 h, 0.5 h, 1 h, 2 h, 3 h, 5 h, and 7 h, according to the feeding time, defined as 0 h. CH4 production was measured over 24 h. Thermographic images measured the maximum, minimum, average and point temperatures at the left and right flanks. The temperature difference between the left and right flanks (left minus right) was calculated each time. Pearson correlation coefficients, multiple regression and principal component analysis were carried out in SAS®. The best prediction of emission intensity of CH4 (kg of CH4 per dry matter intake) was obtained at 3 h after feeding: CH4/DMI = 13.9016-0,38673 * DifP2 + 3.39089 * DifMed2 (R² = 0.48), using the difference between left and right flanks for point and average temperature measures. Therefore, infrared thermography can be used as an indicator of CH4 production in hair sheep three hours after feeding.

Comparative study of the reproductive and growth performance of the Hamra and Rumbi ovine breeds.

Growth and reproductive performance traits are important economic indicators for analyzing the overall performance of breeding systems. This study aims to evaluate the comparative performance of two Algerian sheep (Rumbi and Hamra) in terms of growth and reproductive performance, and the effect of factors such as breed, season of birth, mode of birth and age of the mother on this performance in a semi-intensive breeding system. The reproductive performance of 577 Rumbi ewes and 1328 Hamra ewes bred at the Tiaret and Saïda experimental stations respectively, was analyzed using performance monitoring data. Fertility rates for the Rumbi and Hamra breeds of 87.14% and 78.8% respectively were practically similar (p > 0,05). Litter size at birth and weaning was significantly higher in the Hamra breed than in the Rumbi breed (p < 0,05). Weaning mortality was significantly higher in the Hamra breed than in the Rumbi breed, with an average of 22.60% versus 14.94% (p < 0,05). The effect of factors showed that there was a highly significant effect of the mother's age and season of birth on the reproductive performance of the Hamra and Rumbi breeds with a p < 0.0001 on fertility, litter size at birth, litter size at weaning and fertility. There was a significant effect of the year factor on reproductive performance with p = 0,013 for the Hamra breed and p = 0,031 for the Rumbi breed. The results of this study showed that Rumbi lambs were heavier at birth than Hamra lambs. The values observed were 4,86 kg versus 3,10 kg for the Hamra breed, with a highly significant difference (p < 0,0001), so that the average daily pre-weaning weight gains of Rumbi lambs were higher than those of Hamra lambs, at 0,195 kg/day versus 0,113 kg/day for Hamra lambs, with a high significance (p < 0,0001). The effect of factors showed that there was a significant effect of the mother's age on the ADGs (0-30), (30-70) and (70-90) of the Hamra and Rumbi breeds with a p = 0,034 and p = 0,02 respectively. There was also a highly significant effect of the birth mode effect on ADGs (0-30), (30-70) and (70-90) only for the Hamra breed with a p = 0,004. The effect of the birth weight on ADGs was not significant for both Hamra and Rumbi breeds with a p > 0,05. According to the findings of this study, the Hamra breed had superior reproductive potential and the Rumbi breed had superior growth. The Hamra breed showed better maternal skills in terms of fertility and prolificacy, while the Rumbi breed showed better lamb growth performance. Consequently, these results could be used for selective sheep breeding, taking into account the random effects of the environment and the potential of each breed.

Genomic and transcriptomic landscape to decipher the genetic basis of hyperpigmentation in Lanping black-boned sheep (Ovis aries).

BACKGROUND: Lanping black-boned sheep (LPB) represent a distinctive mammalian species characterized by hyperpigmentation, resulting in black bone and muscle features, in contrast to their conventional counterparts exhibiting red muscle and white bone. The genetic basis underlying LPB hyperpigmentation has remained enigmatic. METHODS: In this study, we conducted whole-genome sequencing of 100 LPB and 50 Lanping normal sheep (LPN), and integrated this data with 421 sequenced datasets from wild and domestic sheep, shedding light on the genetic backdrop and genomic variations associated with LPB. Furthermore, we performed comparative RNA-Seq analysis using liver sample to pinpoint genes implicated in the pigmentation process. We generated a comprehensive dataset comprising 97,944,357 SNPs from 571 sheep, facilitating an in-depth exploration of genetic factors. RESULTS: Population genetic structure analysis revealed that the LPB breed traces its origin back to LPN, having evolved into a distinct breed. The integration of positively selected genes with differentially expressed genes identified two candidates, ERBB4 and ROR1, potentially linked to LPB hyperpigmentation. Comparative analysis of ERBB4 and ROR1 mRNA relative expression levels in liver, spleen, and kidney tissues of LPB, in comparison to Diqing sheep, revealed significant upregulation, except for ERBB4 in the liver. Gene expression heatmaps further underscored marked allelic frequency disparities in different populations. CONCLUSION: Our findings establish the evolutionary lineage of the LPB breed from LPN and underscore the involvement of ERBB4 and ROR1 genes in melanin synthesis. These results enhance our comprehension of the molecular basis of hyperpigmentation and contribute to a more comprehensive depiction of sheep diversity.

Effects of protein grass hay as alternative feed resource on lamb's fattening performance and meat quality.

Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.