Body Conformation Research Articles

Genome-wide association study identifies candidate genes affecting body conformation traits of Zhongwei goat

BackgroundIdentifying markers or genes crucial for growth traits in Zhongwei goats is pivotal for breeding. Pinpointing genetic factors linked to body size gain enhances breeding efficiency and economic value. In this study, we used the MGISEQ-T7 platform to re-sequence 240 Zhongwei goats (133 male; 107 female) belonging to 5 metrics of growth traits at different growth stages (40 days and 6 months, here in after referred to as 40d and 6 m), namely, Body Weight (BW), Body Height (BH), Body Length (BL), Chest Circumference (CC), Tube Circumference (TC) were examined. A Genome-wide association study (GWAS) was conducted to identify candidate genes associated with the five indicators of body conformation traits, thereby establishing a foundation for subsequent investigations into the biological functions of these genes.ResultsA total of 19.89 Tb of raw data was generated with an average sequencing depth of about 20×. After quality control, 15,958,716 SNPs were available for the analysis. A total of 342 genome-wide significant SNPs were obtained. Among them, in the two physiological stages of 40d and 6 m, 147 and 32 SNPs were significantly associated with BW; 1 and 4 SNPs were significantly associated with BH; 19 and 6 SNPs were significantly associated with BL; 33 and 64 SNPs were significantly associated with CC, 34 and 2 SNPs were significantly associated with TC. These SNPs were annotated to 425 candidate genes. Finally, A total of 39 candidate genes are closely related to biological processes such as skeletal muscle development, skeletal formation, carcass quality, and embryonic development, where ADIPOQ, CCDD39, PTPRT, ZNF215, VRTN, ABCD4, DLST, ADAMTS2, ROBO1, AKAP13, AQPI, SOX2, and AHSG were identified as an important component of the genetic framework that may control somatic conformational traits in Zhongwei goats. which warrants further investigation and review. We verified the polymorphism of 11 SNPs by KASP, and found that Chr13_g.11,700,438 A > G, Chr15_g.37,120,328 A > G, Chr6_g.7,209,383 C > T, Chr20_g.51277932T > A, Chr19_g.17,078,199 A > G, and Chr1_g.79,943,276 C > T were significantly genotyped in verified populations (P < 0.001).ConclutionIt is the first GWAS study to analyze genomic data from 40d and 6 m of Zhongwei goats to understand the molecular genetic mechanisms of growth. Our research identified a series of SNPs and candidate genes associated with growth traits, which could assist us in developing the meat production trait in Zhongwei goats.

The Evolution and Role of Molecular Tools in Measuring Diversity and Genomic Selection in Livestock Populations (Traditional and Up-to-Date Insights): A Comprehensive Exploration.

Distinctive molecular approaches and tools, particularly high-throughput SNP genotyping, have been applied to determine and discover SNPs, potential genes of interest, indicators of evolutionary selection, genetic abnormalities, molecular indicators, and loci associated with quantitative traits (QTLs) in various livestock species. These methods have also been used to obtain whole-genome sequencing (WGS) data, enabling the implementation of genomic selection. Genomic selection allows for selection decisions based on genomic-estimated breeding values (GEBV). The estimation of GEBV relies on the calculation of SNP effects using prediction equations derived from a subset of individuals in the reference population who possess both SNP genotypes and phenotypes for target traits. Compared to traditional methods, modern genomic selection methods offer advantages for sex-limited traits, low heritability traits, late-measured traits, and the potential to increase genetic gain by reducing generation intervals. The current availability of high-density genotyping and next-generation sequencing data allow for genome-wide scans for selection. This investigation provides an overview of the essential role of advanced molecular tools in studying genetic diversity and implementing genomic selection. It also highlights the significance of adaptive selection in light of new high-throughput genomic technologies and the establishment of selective comparisons between different genomes. Moreover, this investigation presents candidate genes and QTLs associated with various traits in different livestock species, such as body conformation, meat production and quality, carcass characteristics and composition, milk yield and composition, fertility, fiber production and characteristics, and disease resistance.

Genome-wide association analysis of body conformation traits in Chinese Holstein Cattle

BackgroundThe body conformation traits of dairy cattle are closely related to their production performance and health. The present study aimed to identify gene variants associated with body conformation traits in Chinese Holstein cattle and provide marker loci for genomic selection in dairy cattle breeding. These findings could offer robust theoretical support for optimizing the health of dairy cattle and enhancing their production performance.ResultsThis study involved 586 Chinese Holstein cattle and used the predicted transmitting abilities (PTAs) of 17 body conformation traits evaluated by the Council on Dairy Cattle Breeding in the USA as phenotypic values. These traits were categorized into body size traits, rump traits, feet/legs traits, udder traits, and dairy characteristic traits. On the basis of the genomic profiling results from the Genomic Profiler Bovine 100 K SNP chip, genotype data were quality controlled via PLINK software, and 586 individuals and 80,713 SNPs were retained for further analysis. Genome-wide association studies (GWASs) were conducted via GEMMA software, which employs both univariate linear mixed models (LMMs) and multivariate linear mixed models (mvLMMs). The Bonferroni method was used to determine the significance threshold, identifying gene variants significantly associated with body conformation traits in Chinese Holstein cattle. The single-trait GWAS identified 24 SNPs significantly associated with body conformation traits (P < 0.01), with annotation leading to the identification of 21 candidate genes. The multi-trait GWAS identified 54 SNPs, which were annotated to 57 candidate genes, including 39 new SNPs not identified in the single-trait GWAS. Additionally, 14 SNPs in the 86.84–87.41 Mb region of chromosome 6 were significantly associated with multiple traits, such as body size, udder, and dairy characteristics. Four genes—SLC4A4, GC, NPFFR2, and ADAMTS3—were annotated in this region.ConclusionsA total of 63 SNPs were identified as significantly associated with 17 body conformation traits in Chinese Holstein cattle through both single-trait and multi-trait GWAS analyses. Sixty-six candidate genes were annotated, with 12 genes identified by both methods, such as SLC4A4, GC, NPFFR2, and ADAMTS3, which are involved in pathways such as growth hormone synthesis and secretion, sphingolipid signaling, and dopaminergic synapse pathways. These findings provide potential genetic marker information related to body conformation traits for the breeding of Chinese Holstein cattle.

Long-lasting effects of in utero heat stress on subsequent performances of heifers and primiparous cows

The performance of an adult dairy cow may be influenced by heat stress that occurs during her gestation. The present study investigated potential effects of temperature-humidity index (THI) experienced by a cow during pregnancy, on the gestated daughter's performance on her first lactation, for the French Holstein and Montbeliarde dairy cattle populations. Fourteen traits were analyzed, all measured on genotyped cows: 305-d milk, fat, and protein yields, 305-d somatic cell score, clinical mastitis (both occurrence and number of events), body conformation traits, and heifer and cow conception rate. To study the effect of heat stress, we considered the THI experienced by the gestating cow, averaged for each month of her pregnancy and then categorized in 7 classes (≤40; 40-45; 45-50; 50-55; 55-60; 60-65; and >65). These average THI classes were then fitted as categorical covariates in the regression models used for this study, which included other fixed effects, and the genomic estimated breeding value as a covariate, both specific to each trait, the latter previously obtained from the official French evaluations. The THI effect was therefore estimated as the deviation between the observed and the predicted performances. In general, the estimated heat stress effects were small, presenting limited practical impact on the studied traits, and particularly for fertility and udder health, the estimated heat stress effects were not statistically significant. For the production traits, i.e., milk, fat, and protein yields, the estimated effect associated to high THI experienced at the beginning of the gestation was negative, and lightly positive when associated to high THI experienced by the dam at the end of her pregnancy. Finally, our results suggest that under the current French climate conditions, heat stress experienced by cows during any stage of their pregnancy has limited impact on future performances of their gestated daughters, however we cannot exclude that significant in utero heat stress effect may be present in climate conditions warmer than the French.

Genome-wide association study for milk yield, frame, and udder conformation traits of Gir dairy cattle

Genome-wide association studies (GWAS) are employed to identify genomic regions and candidate genes associated with several traits. The aim of this study was to perform a GWAS to identify causative variants and genes associated with milk yield, frame, and udder conformation traits in Gir dairy cattle. Body conformation traits were classified as "frame," and "udder" traits for this study. After genotyping imputation and quality control 42,105 polymorphisms were available for analyses and 24,489 cows with pedigree information had phenotypes. First, P-value was calculated based on the variance of the prediction error of the SNP-effects on the first iteration. After that, 2 more iterations were performed to carry out the weighted single-step genome-wide association methodology, performed using genomic moving windows defined based on linkage disequilibrium. The significant SNPs and top 10 windows explaining the highest percentage of additive genetic variance were selected and used for QTL and gene annotation. The variants identified in our work overlapped with QTLs from the animal QTL database on chromosomes 1 to 23, except for chromosome 4. The Gir breed is less studied than the Holstein breed and as such the animal QTL database is biased to Holstein results. Hence it is noteworthy that our GWAS had similarities with previously described QTLs. These previously known QTLs were related to milk yield, body height, rump angle, udder width, and udder depth. In total, 5 genes were annotated. Of these genes, FAM13A and CMSS1 had been previously related to bone and carcass weight in cattle.

Principal Component Analysis of Morphometric Traits of Tripura Desi Cattle

Background: In 234 cows of Tripura desi cattle from three districts, 18 different biometric traits were measured and analyzed by PCA to explain body conformation. These traits included body length, height at withers, heart girth, paunch girth etc. The native cattle in Tripura are of a smaller breed, according to the average of these several traits. Methods: Six factors that accounted for roughly 75.67% of the variation overall were found using factor analysis with promax rotation. Explaining 26.07% of the total variation, factor 1 characterized the overall body structure. The measurements of tail length, shank length, heart girth, paunch girth, circumference of horn and horn length were significantly positive with high loadings. Result: The outcome indicates that a significant decrease in the number of biometric parameters required to record in order to explain body conformation could lead to the application of principal component analysis (PCA) in breeding programmes. As a result, the study will support conservation efforts and the stabilization of this non-descript breed of cow.

Evaluations of Morphometric Traits and Body Conformation Indices of Horse Ecotypes Reared in the Highlands of Bale Eco-Region, Ethiopia.

Morphometric traits discrepancies are associated with production, reproduction, adaptation and behaviours in horses. It also determines the design of harnessing implements, physical injury level and working performance of the native horses. Thus, the study was conducted to evaluate morphometric traits and body conformation indices of horse ecotypes reared across four districts of Bale Zone, Ethiopia. Data of croup height, croup length, hip height, mid-back height, wither height, hip width, thoracic depth, chest width, body length, sternum height, thorax perimeter and cannon perimeter were measured in 500 horses (294 male and 206 female). Using those traits, 17 body conformation indices were calculated to define the horses for multi-faceted performances. The study revealed that croup height, hip height, wither height, hip width, croup length, body length, thorax perimeter and sternum height were significantly (p < 0.0001) different among the studied districts. The district effect was also significant at p < 0.05 for mid-back height, thoracic depth, chest width and cannon perimeter. The sexual dimorphism effect was statistically significant for all measured traits; however, females were inferior to males except for cannon perimeter. Body conformation indices of pelvic index, body index, transversal pelvic index and weight were highly significant (p < 0.0001) among the studied districts. The sex dimorphism effect was significant (p < 0.001) for dactyl-costal index, pelvic index, longitudinal pelvic index, transversal pelvic index, weight, tare index 1 (trot or gallop), tare index 2 (walk) and riding comfort degree, while non-significant (p > 0.05) for the remaining indices. The studied horses were classified as mediline, elipometric, light, small and suitable riding ecotypes with a medium-conforming body structure and good capacity for carrying loads on carts and backs for functional effectiveness. The correlations of body conformation indices ranged from very high to low, with positive and negative associations for functional capabilities. Therefore, selection for improvement needs to rank morphometric traits and body conformation indices in correlation to developing racing and modern sport horses in the highlands of the Bale eco-regions. Further, molecular studies will be essential to determine whether the predominated phenotypic multiplicity is genetic or environmentally progressed.

Genomic Prediction and Genome-Wide Association Studies for Productivity, Conformation and Heat Tolerance Traits in Tropical Smallholder Dairy Cows.

Genomic selection (GS) and genome-wide association studies (GWAS) have not been investigated in Vietnamese dairy cattle, even for basic milk production traits, largely due to the scarcity of individual phenotype recording in smallholder dairy farms (SDFs). This study aimed to estimate heritability (h2) and test the applicability of GS and GWAS for milk production, body conformation and novel heat tolerance traits using single test day phenotypic data. Thirty-two SDFs located in either the north (a lowland vs. a highland) or the south (a lowland vs. a highland) of Vietnam were each visited for an afternoon and the next morning to collect phenotype data of all lactating cows (n = 345). Tail hair from each cow was sampled for subsequent genotyping with a 50K SNP chip at that same visit. Milk production traits (single-test day) were milk yield (MILK, kg/cow/day), energy corrected milk yield adjusted for body weight (ECMbw, kg/100 kg BW/day), fat (mFA, %), protein (mPR, %) and dry matter (mDM, %). Conformation traits were body weight (BW, kg) and body condition score (BCS, 1 = thin to 5 = obese). Heat tolerance traits were panting score (PS, 0 = normal to 4.5 = extremely heat-stressed) and infrared temperatures (IRTs, °C) at 11 areas on the external body surface of the cow (inner vulval lip, outer vulval surface, inner tail base surface, ocular area, muzzle, armpit area, paralumbar fossa area, fore udder, rear udder, forehoof and hind hoof), assessed by an Infrared Camera. Univariate linear mixed models and a 10-fold cross-validation approach were applied for GS. Univariate single SNP mixed linear models were applied for the GWAS. Estimated h2 (using the genotype information to build relationships among animals) were moderate (0.20-0.37) for ECMbw, mFA, mPR, mRE, BW, BCS and IRT at rear udder; low (0.08-0.19) for PS and other IRTs; and very low (≤ 0.07) for MILK, ECM and mDM. Accuracy of genomic estimated breeding values (GEBVs) was low (≤ 0.12) for MILK, ECM, mDM and IRT at hind hoof; and moderate to high (0.32-0.46) for all other traits. The most significant regions on chromosomes (BTA) associated with milk production traits were 0.47-1.18 Mb on BTA14. Moderate to high h2 and moderate accuracies of GEBVs for mFA, mPR, ECMbw, BCS, BW, PS and IRTs at rear udder and outer vulval surface suggested that GS using single test day phenotypic data could be applied for these traits. However, a greater sample size is required to decrease the bias of GEBVs by GS and increase the power of detecting significant quantitative trait loci (QTLs) by GWAS.

Assessment of horse breeding and husbandry practices in southwest Ethiopia: Its implication to design breeding program

Ethiopian horses are multipurpose horses that have socioeconomic significance for smallholder farmers. However, studies regarding their husbandry practices have received little attention. Thus, the current study was conducted to assess the horse husbandry practices in the southwest Ethiopia. Data were collected through semi-structured questionnaires from a total of 196 randomly selected respondents. The general linear model and frequency procedures of the Statistical Analysis System (SAS 9.0) were used to analyze the quantitative and qualitative data, while indices were calculated using Microsoft Excel 2016. Most of the respondents from the Telo district were illiterate, while the percentage of literate farmers was greater in the Gesha and Masha districts. The within-household flock structure and level of importance were dominated by cattle and sheep, followed by horses. The horses were used for transport, draft power, and breeding purposes. In terms of shelters, the horses in the Telo district stayed in shelters, while the horses in the Masha district stayed in forests during both the dry and wet seasons. However, the majority of the horses in the Gesha district were sheltered during the wet season, while they were left to stay in the forest during the dry season. The respondents provided supplementary feed and water to their horses while the water point was located within a kilometer distance. Government and private veterinary shops were the primary sources of veterinary services. Farmers sold their horses at the local market. Castration was performed to minimize aggressiveness. Body size, conformation, and temperament were used as sire selection criteria. An increasing trend in horse population size due to increased farmer interest was observed. In the studied areas, horses were found to be highly important to the livelihood of the farmers. However, horse husbandry practices were led by a considerably greater number of illiterate farmers. Moreover, horse management activities, including the housing of horses, need more attention. Therefore, successive awareness-raising campaigns, including the introduction of formal schooling, are recommended to improve the horse breeding and husbandry practices. Moreover, breeding programs with the aim of genetic improvement and conservation need to be designed to optimize the sustainable utilization of the horses.

Myostatin gene polymorphisms do not determine muscle hypertrophy in buffaloes: A case report

The aim of the study was to detect variations in the exonic and intronic regions of the myostatin gene in buffaloes with different body conformations. The regions of the gene were analyzed using the PCR-sequencing technique comparing an animal with muscle hypertrophy and ten animals with normal musculature. The hypertrophied buffalo sequence was compared to the others and no exclusive genotype was identified. It suggests that the found MSTN variants are not singly associated to muscle hypertrophy in buffaloes.

Genome-Wide Association Study on Body Conformation Traits in Xinjiang Brown Cattle.

Body conformation traits are linked to the health, longevity, reproductivity, and production performance of cattle. These traits are also crucial for herd selection and developing new breeds. This study utilized pedigree information and phenotypic (1185 records) and genomic (The resequencing of 496 Xinjiang Brown cattle generated approximately 74.9 billion reads.) data of Xinjiang Brown cattle to estimate the genetic parameters, perform factor analysis, and conduct a genome-wide association study (GWAS) for these traits. Our results indicated that most traits exhibit moderate to high heritability. The principal factors, which explained 59.12% of the total variance, effectively represented body frame, muscularity, rump, feet and legs, and mammary system traits. Their heritability estimates range from 0.17 to 0.73, with genetic correlations ranging from -0.53 to 0.33. The GWAS identified 102 significant SNPs associated with 12 body conformation traits. A few of the SNPs were located near previously reported genes and quantitative trait loci (QTLs), while others were novel. The key candidate genes such as LCORL, NCAPG, and FAM184B were annotated within 500 Kb upstream and downstream of the significant SNPs. Therefore, factor analysis can be used to simplify multidimensional conformation traits into new variables, thus reducing the computational burden. The identified candidate genes from GWAS can be incorporated into the genomic selection of Xinjiang Brown cattle, enhancing the reliability of breeding programs.

Exploring body morphometry and weight prediction in Ganjam goats in India through principal component analysis.

The body conformations of 262 adult Ganjam goats were subjected to principal component analysis (PCA) with 11 morphometric variables. The results were then used to predict the mature body weight of the goats. Most of the traits were positively correlated, and the correlations were statistically significant. The three main components that the PCA recovered explained 76.12% of the variation in body morphometry overall. The first component accounted for approximately 54.74% of the overall variation and described almost all the traits except ear length and tail length, as indicated by high component loadings. The second component accounted for approximately 11.48% of the variation, mostly accounting for the variation in tail length. The principal component accounted for 9.89% and mostly explained the variation in ear length. The communalities ranged between 0.557 (horn length) and 0.848 (chest circumference) for the first three extracted components. The highest percentage of variability in chest girth was explained by the first three principal components, whereas it was the lowest for the horn length. In the context of predicting body weight through stepwise regression analysis, nine primary variables accounted for 57.3% of the total variance in body weight. Conversely, utilizing the first principal component alongside six additional principal components as independent variables resulted in capturing 56.3% of the variation in the adult live weight of goats while maintaining model comparability with other pertinent parameters. PCA was used efficiently for body weight prediction from major morphometric traits of Ganjam goats addressing the multicollinearity issue.

Exercise Volume Provides New Insight into the Effects of Housing Systems on Chicken Body Conformation, Carcass Traits, Meat Quality, and Serum Biochemical Parameters.

This study aims to investigate the dynamic changes in daily step counts under different housing systems and further explore the effects of housing system on the body conformation, carcass traits, meat quality, and serum biochemical parameters of a Chinese indigenous chicken breed. At 60 d of age, 300 Jiuyuan Black male chickens with similar body weights in each housing system were further raised until the age of 150 d. At 90, 120, and 150 d of age, in both cage-reared and free-range systems, the top 20 chickens with the highest step counts measured using pedometers and the bottom 20 chickens with the lowest step counts were designated as the cage high-steps group (CHS), the cage low-steps group (CLS), the free-range high-steps group (FHS), and the free-range low-steps group (FLS), respectively. The results show that, at any age stage, the average daily steps (ADS) and total steps (TS) of the FHS group are significantly higher than the other three groups (p < 0.05). The TS of almost all groups showed an overall downward trend as the age increased. Increased exercise volume results in reduced shank length (90 d), breast width (90 d), and keel length (150 d) (p < 0.05). Only birds at 90 d of age from the FHS and FLS groups exhibited lower live body weight, carcass weight, half-eviscerated weight, eviscerated weight, breast muscle weight, leg muscle weight, and percentage of eviscerated weight than the CLS group (p < 0.05). Birds from the FHS group showed the highest heart weight values but the lowest abdominal fat weight values among these four groups (p < 0.05). Both the breast and leg muscle samples from the FHS group displayed higher dry matter and shear force than those from the CHS and CLS groups (p < 0.05). The FHS group displayed the lowest intramuscular fat among the four groups (p < 0.05). The creatine kinase (CK) and lactate dehydrogenase (LDH) levels in chickens of all age stages were almost observed to rise with increased physical activity. In conclusion, free-range chickens with more exercise volume exhibited an elevated heart weight and reduced abdominal fat but showed negative effects on some body measurements and carcass traits. These results can provide a theoretical basis for the selection of different housing systems for Chinese indigenous chickens.

Reasons and Criteria for Selecting and Culling Dairy Cows in Small and Medium Farms in the Northeastern Region of Thailand

The objective of this study was to investigate the criteria for cow culling and the methods used for semen selection in small and medium dairy farms in Thailand. Dairy cows on small and medium farms are culled for many different reasons. Methods of selection and culling were examined using data collected from a questionnaire asking about the number of milking cows, farm experience in raising dairy cows, criteria used for culling cows, selection of new cows, replacement cattle, and semen for breeding. Ninety-one farms were randomly selected using a snowball technique from dairy cooperatives in Khon Kaen, Maha Sarakham, and Sakon Nakhon Provinces, Thailand, with data analyzed using ANOVA and Chi-square statistics. The results showed that most farmers did not cull cows due to low milk production or aging (71.43%, 72.53%) and used 5 to &gt;12 insemination events as a criterion for involuntary culling (50.55%). Chronic mastitis was the highest health reason for culling cows (52.10%). Farmers usually kept on-farm female calves as replacement cows (41.67%), chosen by considering their dams’ milking ability. Most farmers (67.00%) let an artificial inseminator select suitable semen for their cows. When selecting pregnant heifers for replacement, the farmers considered body conformation, udder characteristics, and cow price. Farmers with small and medium farms conducted low levels of voluntary culling and paid less attention to the genetic information of the semen. In summary, this study explains various factors influencing the selection and culling of dairy cows. Challenges leading to cattle culling included mastitis and infertility. Educating farmers on hygiene, reproductive systems, and household accounting is imperative as it facilitates sustainable cattle rearing practices.

Production system analysis and breeding practices of indigenous goats in North Wollo zone, Amhara region, Ethiopia

ABSTRACT This study describes the goat production system and breeding practices in selected districts of North Wollo zone, Ethiopia. Data were collected from 180 respondents through a semi-structured questionnaire and group discussions. Descriptive and GLM procedures were employed for data analysis. A mixed crop-livestock production system was the main production system in the area. The mean number of goats per household is 9.66 and they are mainly kept for cash income and meat consumption. The flock structure of indigenous goats consisted of a large number of female goats. Natural pasture and crop residue were the major feed resources in the dry and wet seasons, with an overall mean of 37.53% and 54.26%, respectively. Feed shortage, diseases, and drought were the major constraints for goat production. Most goat owners (97.1%) practiced an uncontrolled mating system. Most farmers (88.93%) reported selecting breeding goats to be a parent for the next generation. Body conformation and coat colour were the preferred traits for the selection of goats. The current level of goat management and breeding methods would not significantly enhance goats’ productivity and profitability. Therefore, designing management and genetic improvement programmes would be vital to improving the productivity of indigenous goats.

Genome-Wide Association Study as an Efficacious Approach to Discover Candidate Genes Associated with Body Linear Type Traits in Dairy Cattle.

Body shape traits are very important and play a crucial role in the economic development of dairy farming. By improving the accuracy of selection for body size traits, we can enhance economic returns across the dairy industry and on farms, contributing to the future profitability of the dairy sector. Registered body conformation traits are reliable and cost-effective tools for use in national cattle breeding selection programs. These traits are significantly related to the production, longevity, mobility, health, fertility, and environmental adaptation of dairy cows. Therefore, they can be considered indirect indicators of economically important traits in dairy cows. Utilizing efficacious genetic methods, such as genome-wide association studies (GWASs), allows for a deeper understanding of the genetic architecture of complex traits through the identification and application of genetic markers. In the current review, we summarize information on candidate genes and genomic regions associated with body conformation traits in dairy cattle worldwide. The manuscript also reviews the importance of body conformation, the relationship between body conformation traits and other traits, heritability, influencing factors, and the genetics of body conformation traits. The information on candidate genes related to body conformation traits provided in this review may be helpful in selecting potential genetic markers for the genetic improvement of body conformation traits in dairy cattle.

EFFECT OF AGE AND BODY WEIGHT ON CONFORMATION TRAITS IN KANO BROWN DOES AT SMALL HOLDER SYSTEM

The study was conducted to determine the effect of age and body weight on conformation traits in Kano brown does as well as to determine the relationship between the conformation traits and body weight using 110 Kano Brown Does at three age groups (9-12, 13-24 and 25-36 months). The body weight was taken and recorded in kilogram. The conformation traits used for the study were heart girth (HG), body depth (BD), withers height (WH), body length (BL), stature (ST), rump width (RW) and chest width (CW). These conformation traits were measured with flexible tape in centimeters. The experimental result showed that age significantly (P&lt;0.01) influenced heart girth, body depth, stature and height at withers. However body length rump width and chest width had no significant influenced on age. All the body conformation traits except body length, rump width and chest width increased with increase in age. Body weight significantly (P&lt;0.01) influenced all the conformation traits evaluated except that chest width had no significant (P&gt;001; P&gt;0.05) influenced on the body weight. The correlation coefficient obtained for the measured traits were positive and significant. Based on the result obtained from this study it's recommended that age and body weight should be taken in to consideration for selection and breeding in Kano Brown does.

Genomic patterns of selection in morphometric traits across diverse Indian cattle breeds.

This study seeks a comprehensive exploration of genome-wide selective processes impacting morphometric traits across diverse cattle breeds, utilizing an array of statistical methods. Morphometric traits, encompassing both qualitative and quantitative variables, play a pivotal role in characterizing and selecting livestock breeds based on their external appearance, size, and physical attributes. While qualitative traits, such as color, horn structure, and coat type, contribute to adaptive features and breed identification, quantitative traits like body weight and conformation measurements bear a closer correlation with production characteristics. This study employs advanced genotyping technologies, including the Illumina BovineSNP50 Bead Chip and next-generation sequencing methods like Reduced Representation sequencing, to identify genomic signatures associated with these traits. We applied four intra-population methods to find evidence of selection, such as Tajima's D, CLR, iHS, and ROH. We found a total of 40 genes under the selection signature, that were associated with morphometric traits in five cattle breeds (Kankrej, Tharparkar, Nelore, Sahiwal, and Gir). Crucial genes such as ADIPDQ, DPP6, INSIG1, SLC35D2 in Kankrej, LPL, ATP6V1B2, CDC14B in Tharparkar, HPSE2, PLAG1 in Nelore, PCSK1, PRKD1 in Sahiwal, and GNAQ, HPCAL1 in Gir were identified in our study. This approach provides valuable insights into the genetic basis of variations in body weight and conformation traits, facilitating informed selection processes and offering a deeper understanding of the evolutionary and domestication processes in diverse cattle breeds.

Evaluation of the current situation of sheep production characteristics in Nkasi District, Tanzania

Abstract. Kapongo RY, Mbaga SH. 2024. Evaluation of the current situation of sheep production characteristics in Nkasi District, Tanzania. Intl J Trop Drylands 8: 44-57. This study was conducted in two divisions, Namanyere and Mkwamba of Nkasi District in the Rukwa Region, Tanzania, to assess the sheep production status of smallholder farmers. Eight wards, namely Namanyere, Mtenga, Chala, Swaila, Kipande, Sintali, Kate, and Isale, were surveyed from November 2010 to April 2011. The random sampling technique was adopted to get 20 respondents from each selected ward. Two villages from each ward were chosen randomly, whereby ten respondents were interviewed in each village. A structured questionnaire was used to collect data from smallholder farmers keeping sheep and was complimented by secondary data from the district council offices. The results showed that sheep strains kept mainly by smallholder farmers were variant crosses of local strains and Red Maasai. The strains were deemed tolerant to diseases/parasites, heat, and drought and had better carcasses. Most smallholder farmers adopted an extensive grazing system during both dry and wet seasons. Breeding was uncontrolled; however, rams were selected based on their body sizes, conformation, and performance (e.g., number of lambs per ewe's lifetime, age at first lambing, and lambing intervals). Traits such as disease tolerance, drought, and heat tolerance scored higher for most strains. The average age at first lambing was 6.5 months, the lambing interval was three months, and the average number of lambs per ewe's lifetime was 14. The constraints to sheep production mostly were poor market availability, endemic diseases, and mortality of lambs. On marketing, fewer sheep were sold in the market compared to goats, and the price was 22% lower than that of goats.

Assessment of body metrics, weight, and carcass yields in dusky grouper (Epinephelus marginatus) through correlation and path analysis: Implications for optimizing genetic breeding programs

One of the objectives of aquaculture selective breeding programs is to enhance body conformation traits, often by using indirect criteria like correlation between live body measurements and carcass traits. This research investigated the relationship between live body measurements and carcass traits in dusky grouper (Epinephelus marginatus). We assessed the relationship between body measurements and carcass traits in 150 farmed dusky groupers with an average weight of 680 ± 221 g. The fish were measured for length, width, height, and length of head, and then processed to obtain weights (body, fillet, steaks, head, and residues) and yields (carcass, fillet, steaks, head, and residues). Path analysis was employed to estimate direct and indirect effects, with body part weight and yields as dependent variables and morphometric measurements and relationships as explanatory variables. The findings indicate that morphometric measurements can be used to estimate farmed dusky grouper body weights and carcass yields. Among the morphometric measurements and relationships examined, fish body height and standard length were identified as the main factors influencing variation in body weights and carcass yields.