Small Ruminant Research最新文献

The aim of this study was to assess the population structure and genetic diversity along with determining the accuracy of ongoing selection program in a closed flock of Intercross sheep through pedigree analysis. The pedigree records of 2245 animals maintained at CSWRI-NTRS, Garsa, Kullu during the period from 2012 to 2023 were utilized to calculate the genealogical information, genetic conservation index and other parameters based on gene origin probabilities. Lambs born during 2020 and 2023 were considered as reference population. ENDOG version 4.8 software package was used for pedigree analysis. Analysis revealed that the mean generation interval for the reference population was 3.20 years with a longer interval in dam-offspring pathways relative to sire-offspring pathways. Average inbreeding coefficients for whole and reference population were 0.21 and 0.49 % and corresponding average relatedness was 1.24 and 1.72 %, respectively. The average maximum, equivalent and completed generations were 2.50, 1.96 and 1.63 with 0.12 %, 0.17 % and 0.20 % increase in inbreeding coefficient, respectively. This resultant effective population size estimated using individual increase in inbreeding was 156.52. Effective numbers of founders (f_e) and ancestors (f_a) was 68 and 61, respectively for reference population with a ratio of 1.11, indicating occurrence of minor effects of bottleneck in the flock. The genetic contribution of most influent ancestors contributing 50 % of the gene pool was only 23. The estimated founder genome (f_g) and non-founder genome (f_ng) were 35.87 and 75.91, respectively in the present population. The estimate for f_g/f_a ratio was 0.59 which explained that 59 % of the original genetic diversity is exit in the reference population. Genetic conservation index (GCI) ranged from 1 % to 20.28 % with a mean value of 4.91 %. Overall, males recorded a slightly higher GCI than females, i.e., 5.23 vs 4.65 %, respectively. The results revealed that, the population has augmented genetic diversity and low level of inbreeding. Small fraction of genetic diversity was vanished due to unequal contribution of founders and minor bottleneck effects occurred due to disproportionate contribution of breeding animals to gene pool of population. Use of a sufficient number of breeding rams and optimum contribution selection (OCS) is recommended to maintain the genetic diversity as well as enhancing production potential in this population.

This study aimed to evaluate the effects of two additional doses of chromium propionate on performance, carcass characteristics and meat quality, bone density and metabolites. A total of 29 uncastrated male lambs were divided into 3 treatments: CTL, no chromium added; Cr0.5, 0.5 mg/kg of DM; and Cr1.5, 1.5 mg/kg of DM. The experimental period lasted for 64 days during which blood samples were taken for biochemical analysis, the animals were weighed for performance evaluation, and individual and daily feed consumption were monitored. At slaughter, data were collected to evaluate carcass and meat characteristics, viscera, and femur weight for bone density. The experimental design was completely randomized with means compared by the Tukey test at 5 % probability. The inclusion of chromium propionate increased dry matter intake (P<0.0001), decreased feed efficiency (P=0.0002), and increased Cr concentration in the meat (P=0.0341). The cholesterol (P=0.0023) and phosphorus (P=0.0213) were lower in Cr0.5, and alkaline phosphatase decreased linearly (P=0.0274). Cr improved the parameters of total leukocytes (P=0.0126), lymphocytes (P=0.0476), and monocytes (P = 0.0058). No effect of Cr was observed on carcass characteristics, commercial cuts, meat quality, viscera, and femur density. Supplementation with 0.5 mg of chromium propionate positively affected the immune system of lambs in feedlots, increasing the amount of chromium in the meat. However, above this amount may reduce dry matter intake and feed efficiency.

This study aimed to (1) measure methane emissions from alpacas grazing in Andean grasslands during the dry season and compare them with those of sheep under similar conditions, and (2) estimate the methane conversion and emission factor for alpacas grazing in Andean grasslands, considering methodology, animal class, and season. The comparison involved nine alpacas and nine sheep, with measurements taken for dry matter intake, diet composition, and enteric methane emissions measured with the sulfur hexafluoride technique. Alpacas selected a more digestible diet than sheep (0.62 vs. 0.50 g/g of dry matter), even with limited feed availability. Methane emissions were similar between the two species. For the second objective, the study used observations from the first objective and mean treatments from a literature review. The developed model predicted methane conversion factors, considering animal class and measurement methodology, with no significant influence observed for season. The predicted methane conversion factors (% gross energy in feed converted to methane) for alpacas grazing in Andean grasslands were 7.71 for juveniles (i.e., tuis) alpacas and 8.71 for adults, corresponding to emission factors of 6.49 and 9.77 g per alpaca and day, respectively. These results emphasize the importance of considering animal class, measurement methods, and regional variations when estimating methane emission factors for alpacas.

This study aims to determine an effect between GH, IGF-I, and Pit-I gene polymorphisms and growth traits such as body weight, heart girth, body length, height at wither, and chest width in Saanen, Alpine, and Boer goat breeds. The polymorphism was identified using the PCR-RFLP technique. GH/HaeIII gene polymorphism results identified two alleles (A and B) and two genotypes (AB and BB). A and B allele frequencies for Saanen, Alpine, and Boer goat breeds were found to be 0.438 and 0.562, 0.444 and 0.556, and 0.197 and 0.803, respectively. AB and BB genotype frequencies were found to be 0.876 and 0.124, 0.889 and 0.111, and 0.394 and 0.606, respectively. IGF-I/HaeIII gene polymorphism results identified two alleles (A and B) and three genotypes (AB, BB, and AA). A and B allele frequencies for the Saanen, Alpine, and Boer breeds were found to be 0.191 and 0.809, 0.173 and 0.827, and 0.182 and 0.818, respectively. The AB, BB, and AA genotype frequencies were found to be 0.315, 0.652, and 0.033 for Saanen, 0.247, 0.704, and 0.049 for Alpine, and 0.242, 0.697, and 0.061 for Boer, respectively. Regarding Pit-I/PstI gene polymorphism, T and C allele frequencies were determined as 0.921 and 0.079, 0.988 and 0.012, and 0.985 and 0.015 for Saanen, Alpine, and Boer breeds, respectively. TT and TC genotype frequencies were found to be 0.843 and 0.157, 0.975 and 0.025, and 0.970 and 0.030 in Saanen, Alpine, and Boer goats, respectively. An association was found between GH polymorphism and chest width in Saanen and Alpine goats and between body weight and heart girth in Boer goats. Additionally, an association was identified between IGF-I polymorphism and body weight in Alpine and chest width in Boer. There was also an association between Pit-I polymorphism and body weight in Alpine goats.

The purpose of this study was to investigate the effectiveness of ascorbic acid and thiamine as an adjunctive therapy with antibiotics in treatment of sheep affected with pneumonia. Twenty male lambs (8–12 months old) with clinical signs of pneumonia were randomly allocated into 1 of 4 treatment groups: A (antibiotics alone), B (antibiotics + thiamine), C (antibiotics + ascorbic acid), and D (antibiotics + thiamine + ascorbic acid). A separate group of five male healthy lambs, matching for weight and age served as the control group, received only distilled water. The primary outcomes were the rate of change in the severity of clinical signs of pneumonia and acute phase protein concentrations, assessed at days 1, 3, 6, and 14 after administration. All groups displayed clinical improvement, with groups C and D exhibiting faster resolution of dyspnea and nasal discharge. Serum total protein, ceruloplasmin, and haptoglobin decreased in all groups, with group D showing the fastest decline. Albumin levels increased significantly in all groups, especially in group D. Fibrinogen levels decreased most notably in D. WBC counts in group D converged with the control group on day 14. In conclusion, this study indicates that co-administration of thiamine and ascorbic acid alongside antibiotics may be more effective in treating pneumonia compared to antibiotics alone. Pneumonic animals receiving both thiamine and ascorbic acid displayed faster resolution of clinical signs and a more pronounced improvement in markers of inflammation compared to other treatment groups.

Gastrointestinal nematode Haemonchus contortus is a major challenge for small ruminant production systems in the Southeast US. Alternative approaches to nematode control are needed to circumvent parasite resistance to chemical anthelmintic. The study aimed to evaluate the in vivo effects of orange oil (ORG) and sunn hemp hay (SH) supplementation on fecal egg counts, FAMACHA© and body condition score (BCS), hematological parameters, nutrient digestibility, and growth performance in Texel ewes. Forty-eight ewes (∼ 6 months; 31.3 ± 4.1 kg body weight) were orally dosed with 10,000 H. contortus larvae (L3 stage). Experimental pens (N=12; 4 ewes/pen) were blocked by low, medium, and high fecal egg counts. Treatments were arranged in a 2 × 2 factorial model with 2 levels each for SH and ORG. Treatments were: 1) Control: Pen receiving coastal bermudagrass based basal diet; 2) ORG: Pens receiving basal diet with orange essential oil; 3) SH: Pens receiving basal diet replacing 20% coastal bermudagrass hay with SH; 4) SH+ORG: Pens receiving SH with ORG. Experimental duration was 6 weeks including one week for adaptation and 5 weeks for data collection. Orange oil was orally dosed (600 mg/kg of body weight) once during week 1 of data collection. Data were analyzed using PROC GLIMIMIX of SAS with SH, ORG, and blocks as fixed factors while pen was used as random factor in the model. Fecal and blood samples, body weight, BCS, and FAMACHA© scores were collected once weekly. ORG was effective at lowering 37% of Strongylids (including Haemonchus contortus) egg counts in fecal samples while no effects were observed with SH. No treatment difference was observed on dry matter intake, and body weight (BW); while dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude protein (CP) digestibility was lower in response to SH supplementation. In conclusion, ORG has anthelmintic potential; however, future studies should explore the mechanism and economic benefit of using ORG for small ruminant producers.

The study was designed as a randomized, prospective, blinded, clinical trial to compare the clinical effects of epidural lidocaine hydrochloride 2% (L2%) alone and in combination with dexmedetomidine (DL2%) in sheep. A total of 19 adult sheep, 14 females & 5 males were assigned to one of the two lumbosacral epidural treatments: L2% (4 mg kg ^–1) and DL2% (2.5 µg kg ^–1 + 4 mg kg ^–1) in a randomized order. The total volume of the drug combination was kept constant. Onset, analgesia, motor blockade, sedation and behaviour were determined before treatment, after effect of treatment and at recovery. Duration of epidural anesthesia and motor blockade were recorded. Heart rate, blood pressure, respiratory rate, rectal temperature and capillary refill time were recorded prior to treatments and every 15 minutes following epidural anesthesia for 60 minutes. Epidural anesthesia was produced with both the treatments effectively and was easily performed in all the studied animals. Both the treatments provided complete analgesia however no significant difference (p = 0.35) was recorded in onset time to analgesia. Duration of epidural anesthesia was significantly greater (p < 0.0001) with DL2% (239.56 ± 19.48 min) than L2% (69.30 ± 3.03 min). Significant extension (p < 0.0001) of motor blockade was recorded with DL2% (251.89 ± 22.18 min) than with L2% (88.30 ± 2.36 min) alone. The median analgesic scores were significantly higher in DL2% in comparison to the L2% alone. Rescue analgesia had to be given in 20% of L2% and 33.3% of DL2%.

The aim of this study is to determine how physiological changes occurring in the uterus during early pregnancy affect echotexture values by computer-assisted analysis of ultrasonographic images of the uterus in pregnant and non-pregnant ewes. It was also aimed to clarify the relationship between the echotextural parameters and progesterone (P₄) hormone in this period. A total of 40 Awassi ewes were used in the study, as Group 1 (n=20) not pregnant ewes, and Group 2 (n=20) pregnant ewes. Transrectal ultrasonography was applied on days 4, 7, 10, 13, 15, 16, and 17 after natural mating and the uterus tissue images were recorded. Blood samples were taken for the measurement of progesterone hormone. Measurements were taken on the uterus ultrasonographic images of the mean grayness value (MGV), homogeneity (HOM), and contrast (CON). In the statistical analyses of the data, two-way repeated measures ANOVA were examined with variance analysis and the Pearson test. It was found a time-related significant difference in the echotexture parameters within the groups of the pregnant and non-pregnant ewes in respect of the MGV, HOM, and CON values (P<0.05). The MGV and HOM values in all the days when measurements were taken after natural mating were significantly higher in the non-pregnant ewes compared to the pregnant group (P<0.001). The CON value was significantly higher in the pregnant ewes than the non-pregnant ewes in all days of measurement after natural mating (P<0.001). A time-related statistically significant difference was determined in the serum P₄ within the groups of pregnant and non-pregnant ewes (P<0.001) and it was higher in the pregnant ewes (P<0.001). A significant negative correlation was determined between P₄ and MGV, and between P₄ and HOM, and a significant positive correlation between P₄ and CON. In conclusion, it was found a significant difference between the pregnant and non-pregnant ewes in respect of the echotextural evaluation of the uterus and the measurement of P₄ hormone. In ewes farming, the early determination of pregnancy and early determination of ewes that are not pregnant gives the opportunity for repeat mating, and the evaluation of changes occurring in the uterus by computer-assisted image analysis can be used as an assistive method for providing additional nutrition in pregnant ewes.

Sesame, a polyunsaturated fatty acid (PUFA)-rich oilseed, can be a highly efficient animal feed to enriched ruminants’ milk with unsaturated fatty acids (UFAs). However, oils and oilseeds inclusion in ruminants’ diets can modify lipid metabolism in the mammary gland and affect milk chemical composition. Although the topic has been well-documented in cattle, a limited number of studies are available in small ruminants, particularly in goats. Given that, twenty-four goats (BW = 44.9 ± 5.4 kg) at 80 ± 10 days in milk were split up into three homogeneous groups (n = 8). The control (CON) group was fed a diet with a Forage/Concentrate ratio = 50/50 with no sesame seeds, while the groups S5 and S10 included whole sesame seeds at a level of 5 % and 10 % of concentrates, respectively, by partially substituting both soybean meal and corn grain. Mammary tissues were sampled on the 100th experimental day using a core needle biopsy. Significant increases (p < 0.05) in the gene expression of COX4I1 and AGPAT1 were observed in the S10 group, while none of the gene’s transcription was adversely affected by the whole sesame seed inclusion. In conclusion, sesame seed inclusion in goats’ diet (up to 10 % of concentrate) has a negligible effect on the transcription profile regulating lipid metabolism in the mammary gland.

The growth in demand and demand for quality in the sheep chain has generated the need for automation techniques in the meat industry and the need to obtain responses with greater speed and standardization. The research aimed to predict tissue characteristics of the carcass and commercial cuts based on measurements obtained by VIA – see oimage analysis, carried out on cold carcasses of hairless lambs, using machine learning employing regressive techniques for variable selection. Information from 72 carcasses of castrated male lambs, aged between 8 and 11 months, with an average cold carcass weight of 16.13 ± 3.98 kg, was used. Images of the right side of the carcasses were captured from the dorsal and lateral views using a digital camera. From the ImageJ2 software, VIA data, measurements and shape descriptors (areas, perimeters, widths, lengths, convexities, solidities) were obtained, combined with cold carcass weight and used to generate four sets of data, called descriptor sets (DSs). Obtaining DS1, DS1’, DS2, DS2’, DS3, DS3’, DS4 AND DS4’. To generate these sets, a database was formed and divided into a training bank (with 70% of the observations) and a test bank (30% of the observations). Multiple linear regression models were developed using Stepwise, LASSO, and Elastic Net regression methods, combined with k-fold cross-validation, to evaluate the performance of the models. The accuracy of the estimates was based on RMSE, R², Pearson correlation and bias metrics. For the variables tested in this study, the proposed shape descriptors were mostly efficient in predicting tissue and weight variables. DS1' with the LASSO technique presented the best adjustments for variables total muscle and fat followed by shoulder, loin and rib cuts. The descriptors tested by this study were able to predict with quality the vast majority of the characteristics tested, the variable cold carcass weight (CCW), introduced as additional predictor, promoted a consistent improvement in the fits of all models. DS1 presented greater constancy for the twenty-three predicted characteristics and Stepwise presented the worst predictive performance, in relation to LASSO and Elastic Net. Despite close adjustments between the generated models, in general, Elastic Net presented lower performance than LASSO.