Analysis of size and conformation of native Creole goat breeds and crossbreds used in smallholder agrosilvopastoral systems in Puebla, Mexico

Prediction of birth weight using body measurements of local caprine population kids raised in a low-input breeding mode under arid environment

The aim of this study is to establish linear measurements of local goat kids at birth and their factors of variation, as well as their possible correlations with birth weight. Additionally, the study analyses statistical models and barymetric functions to predict birth weight of kids based on their morphometric data. The database includes data on 128 goat kids born to 89 goats and 9 bucks in the experimental goat herd at the El GORDHAB station of IRA. Average BW, withers height (L1), heart girth (L2), rump height (L3), and body length (L4) of all kids were 2.45kg, 32.66cm,30.56cm, 33.41cm, and 31.21cm respectively. Results show that in general, local goat kids are small in size and weight at birth, which varies depending on sex, dam age, and type of birth. Highest and positive correlation coefficient value between birth weight and heart girth were observed (r = 0.95). The coefficient of determination (R2) for heart girth (0.78) was higher than other body measurements in single trait evaluation indicating it as the best trait for the predication of birth weight. The most appropriate combination of body measurements (R2 = 0.82) was observed between height at withers and heart girth for predication of birth weight estimation. Developing a system for recording birth weight based on easily obtainable body measurements could be a useful approach for rural areas. Result join the study objective by conceiving feasible genetic improvement plans for agropastoral herds by establishing individual phenotypes estimation even when the classical animal management does not already allowed.

Genome-Wide Association Analysis Reveals Genetic Loci and Candidate Genes for Chest, Abdominal, and Waist Circumferences in Two Duroc Pig Populations

Chest circumference (CC), abdominal circumference (AC), and waist circumference (WC) are regarded as important indicators for improving economic traits because they can reflect the growth and physiological status in pigs. However, the genetic architecture of CC, AC, and WC is still elusive. Here, we performed single-trait and multi-trait genome-wide association studies (GWASs) for CC, AC, and WC in 2,206 American origin Duroc (AOD) and 2,082 Canadian origin Duroc (COD) pigs. As a result, one novel quantitative trait locus (QTL) on Sus scrofa chromosome (SSC) one was associated with CC and AC in COD pigs, which spans 6.92 Mb (from 170.06 to 176.98 Mb). Moreover, multi-trait GWAS identified 21 significant SNPs associated with the three conformation traits, indicating the multi-trait GWAS is a powerful statistical approach that uncovers pleiotropic locus. Finally, the three candidate genes (ITGA11, TLE3, and GALC) were selected that may play a role in the conformation traits. Further bioinformatics analysis indicated that the candidate genes for the three conformation traits mainly participated in sphingolipid metabolism and lysosome pathways. For all we know, this study was the first GWAS for WC in pigs. In general, our findings further reveal the genetic architecture of CC, AC, and WC, which may offer a useful reference for improving the conformation traits in pigs.

Growth performance of Black Bengal, Saanen, and their crossbred F1 as affected by sex, litter size, and season of kidding

The objective of the present study was to determine the factors that influenced growth performance of the goat kids of Black Bengal (BB), Saanen (SA), and their crossbred F1 (male Bengal × female Saanen [BBSA] and male Saanen × female Black Bengal [SABB]). Data for 674 kids were analyzed from 316 litters and 134 does. All kids were weekly measured on their characteristics (body weight, length, height at the withers, and chest girth) from birth to 11 weeks old. The kid's breed and sex, litter size, and season of kidding influenced birth weight and other characteristics through the experiment. The SA and BBSA kids showed similar performance, which were higher than BB and SABB kids. Male kids had higher performance than female kids, and kids from a single litter showed the highest performance. Kids born during rainy season showed lower performance than those born in hot and cool seasons. In conclusion, the crossbred BBSA is superior to SABB or BB to raise in tropical climate Moreover, sex, litter size, and kidding season also affected growth performance during the preweaning period up to 11 weeks old.

Morphostructural Characterization of the Black Creole Goat Raised in Central Mexico, a Currently Threatened Zoogenetic Resource

In order to evaluate the morphostructural variability of the Black Creole goat (BCG), the present study was carried out in a population of 226 animals from eight localities and 14 morphometric variables were taken. Descriptive statistics for the variables were obtained and 10 of these presented variation coefficients of less than 10%. The degree of harmony in the morphology of the population was determined by the number of positive correlations with significant differences (p < 0.05), including a correlation test using Spearman's method. In order to reduce the matrix of variables, a principal components analysis was performed, and it was evaluated based on Kaiser's criteria (eigenvalue > 1). Finally, a hierarchical analysis of conglomerates using Ward's method was performed using the Euclidean distance to evaluate the distances among localities. Morphometric variables were also included to visualize the relationship among the localities and their average per variable. The results showed that the animals evaluated presented a certain degree of homogeneity and maintained a highly harmonic model. The BCG population showed a high aptitude for milk production, which confirmed the zootechnical purpose of the breed. The BCG populations evaluated maintain similar morphostructural profiles specific to them that can distinguish this population from other animal breeds.

Growth and carcass characteristics of three Ethiopian indigenous goats fed concentrate at different supplementation levels

The study was carried out to evaluate the effect of genotypes and concentrate levels on growth performance and carcass characteristics of Bati, Hararghe highland (HH) and Short eared Somali (SS) goat types found in Ethiopia. A 3 × 2 factorial arrangement (3 genotype × 2 concentrate levels) was used to randomly allocate 36 goats (15.2 ± 0.30 kg initial weight); 12 goats from each genotype with age about 1 year were divided randomly into two groups for a feeding trial of 90 days. The two concentrate levels were L1 and L2, where L1 and L2 are levels fed to animals at the rate of 1 and 1.5 % BW, respectively. Hay was fed ad libitum with 20 % refusal rate. The mean daily dry matter intake of the goats was 520.5 g/day. The intake was about 67 g/day higher for L2 than L1 goats. Consequently, L2 goats had significantly (p < 0.05) higher average daily gain, dressing percentage, primal carcass cuts and total non-carcass fat than those fed L1. Among genotypes, HH goats were found to have higher (p < 0.05) carcass weight, heart girth, neck girth, and carcass cuts (legs and shoulders) than SS goats. However, they were not better in dressing percentage than SS goats. Compared to Bati goats, HH goats had significantly (p < 0.05) wider rib-eye area, heavier ribs/racks weights, and better dressing percentage. Despite smaller body size, the performance of SS goats was comparable to Bati goats. In conclusion, the study indicates the potential of Ethiopian indigenous goats to produce optimum amount of meat when supplemented with concentrate at the rate of 1.5 % body weight.

Zoometric measures and their utilization in prediction of live weight of local goats in southern México

Objectives of this study were: (a) to compare live weight (LW) and zoometric measures (ZM) of local goats in two locations, (b) to fit the best regression equation for goat LW prediction using ZM. LW, body length (BL), trunk length (TL), withers height (WH), hearth girth (HG), rump width (RW), rump length (RL), head length (HL), head width (HW), and ear length (EL) were measured in 318 Local does in Amatepec and Tejupilco, State of Mexico. Statistical methods included student’s “t” tests for comparison of means, and correlation, principal components (PC), and multiple linear regression analyses. To evaluate the goodness of fit for LW prediction models the R² value was used as a criterion. Differences (P ≤ 0.05) were found between does of Amatepec and Tejupilco in LW, BL, TL, HG, RL, HL, HW, and EL. In Amatepec, LW was correlated with HG, BL, and HW (P ≤ 0.01), whereas in Tejupilco LW was correlated with HG, BL, TL, and HW (P ≤ 0.01). From the Amatepec measures 5 PC were extracted, and which in a multiple regression analysis explained 83.3 % of the total variance, whereas from Tejupilco 4 PC were extracted, and which in a multiple regression analysis explained 82.4 % of the total variance. The best regression model to predict doe LW in Amatepec included TL, HG, RW, and HW, whereas for Tejupilco the best model included BL, HG, HW, and EL. It is concluded that: (1) Amatepec does surpass those of Tejupilco in LW and most ZM, (2) there are reliable ZM for predicting LW of local does in both locations, HG, and HW being common measures for both populations.

Morphological and microsatellite DNA diversity of Nigerian indigenous sheep

Background

Sheep is important in the socio-economic lives of people around the world. It is estimated that more than half of our once common livestock breeds are now endangered. Since genetic characterization of Nigerian sheep is still lacking, we analyzed ten morphological traits on 402 animals and 15 microsatellite DNA markers in 384 animals of the 4 Nigerian sheep breeds to better understand genetic diversity for breeding management and germplasm conservation.

Results

Morphological traits of Uda and Balami were significantly (P < 0.05) higher than Yankasa, which were both higher than West African Dwarf (WAD) sheep. Stepwise discriminant analysis showed tail length, rump height, chest girth, ear length and chest depth as the most discriminating variables for classification. Mahalanobis distances show the least differentiation between Uda and Balami and the largest between WAD and Balami sheep. While 93.3% of WAD sheep were correctly assigned to their source genetic group, 63.9% of Yankasa, 61.2% of Balami and 45.2% of Uda were classified correctly by nearest neighbour discriminant analysis. The overall high Polymorphism Information Content (PIC) of all microsatellite markers ranged from 0.751 to 0.927 supporting their use in genetic characterization. Expected heterozygosity was high for all loci (0.783 to 0.93). Mean heterozygote deficiency across all populations (0.171 to 0.534) possibly indicate significant inbreeding (P < 0.05). Mean values for F_ST, F_IT and F_IS statistics across all loci were 0.088, 0.394 and 0.336 respectively. Yankasa and Balami are the most closely related breeds (D_A = 0.184) while WAD and Balami are the farthest apart breeds (D_A = 0.665), which is coincident with distance based on morphological analysis and population structure assessed by STRUCTURE.

Conclusions

These results suggest that within-breed genetic variation in Nigerian sheep is higher than between-breeds and may be a valuable tool for genetic improvement and conservation. The higher genetic variability in Yankasa suggests the presence of unique ancestral alleles reflecting the presence of certain functional genes which may result in better adaptability in more agro-ecological zones of Nigeria. These genetic characteristics are potentially useful in planning improvement and conservation strategies in Nigerian indigenous sheep.