Conformation Traits Research Articles

Conformation trait characterization of indigenous goats in selected districts of East Gojjam zone, Amhara region, Ethiopia

ABSTRACT Morphological differences between and within the indigenous goat populations have important economic and socio-cultural values to the communities. This study was phenotypically characterized conformation traits of indigenous goats in selected districts of East Gojjam Zone, Amhara Region, Ethiopia. A total of 706 (589 does, and 117 bucks) mature (>1PPI), healthy, lactating does, and intact bucks goats were used to collect qualitative and quantitative data. The qualitative and quantitative data were analyzed for female and male goats separately using the frequency and general linear model (GLM) procedures of SAS, 9.0, respectively. Most of the does had intermediate fore udder attachment, teat placement side and rearview, and strong central ligament. Most goats were explained by intermediate rear legs set side view, less sloped rump profile, intermediate angle, and strong loin strength. The district and goats dentition had significant influence on does’ bodyweight and most conformation trait measurments. Heart girth (r = 0.82) in does, and neck circumference (r = 0.68) in bucks showed the highest strong and positive correlation (P < 0.001) with bodyweight and were the utmost important variables to predict bodyweight. Indigenous goats in the study area have a dairy aptitude. However, further studies are needed to identify the indigenous goats for their production purpose.

Effect of Feed Form on Body Conformation Traits of Different Hybrids of Broiler Chickens

This research was conducted to measure the exterior characteristics in four hybrids of broilers fed pelleted and commercial mash feed. A total of 112 one-day-old chicks from four broiler hybrids, namely, Arbor Acre, Cobb 500, Marshall, and Ross 308 were used for this experimentation and allocated into four treatments with 28 birds of each hybrid and were replicated four times with 7 birds per replicate in a 2 × 4 factorial experiment. Pelleted and milled (mash) commercial feed was used for this experiment. The feeding trial lasted at the age of 59 days old, and data on the conformation trait were recorded. The results of the conformation traits showed no significant difference ( P &gt; 0.05 ) in any of the parameters measured. Most of the conformation traits examined were positive and strongly correlated with one another. Finally as a suggestion, further deep study needed to be conducted by considering different factors including an interaction effect of the main factors.

Genetic and phenotypic characterization of Kuzi ducks of Odisha and evaluation of carcass quality

In the present investigation, the Kuzi ducks of Odisha were studied with respect to different phenotypic traits and genetic parameters measured for Juvenile traits from 1,718 ducklings hatched in three hatches using 40 sires and 160 dams reared under standard management conditions. Fertility, hatchability, juvenile traits, body weight gains and plumage characteristics were recorded. Carcass characteristics of the drakes were also measured at 20 weeks of age. The average fertility was 75.42% and hatchability on total egg set and fertile egg set basis were 61.79 and 82.10%, respectively. The body weight between male and female showed sexual dimorphisms with respect to body weight and conformation traits from 4th week onwards in Kuzi ducks. The least square body weight recorded at 8 weeks of age in male, female and pooled over sexes were 1,388, 1,231 and 1,282 g, respectively. Heritability estimates for different juvenile traits were moderate to high in magnitude for the traits studied. Body weight recorded at 20 weeks of age was 1,818 g in male and 1,628 g in female. Total edible carcass yield was 76.48% at 20 weeks of age in male. Multi-colour is found to be dominant plumage colour. The study revealed that Kuzi ducks of Odisha have very good potential for duck farming in the country and the body weight of the duck may be improved by selection of the birds and the drake (male) may be used for meat purpose. The growth of the ducklings was very fast from 2 to 8 weeks of age.

Estimation of heritability and breeding values for performance and body conformation traits in Harnali Sheep

The present study was conducted to evaluate the effect of non-genetic factors on performance and body conformation traits along with estimation of heritability and breeding values of these traits in Harnali sheep. Nongenetic factors had significant effect on the performance and body conformation traits in Harnali sheep. Heritability estimates varied from low to moderate for performance traits indicating the presence of genetic variability which could be used for further improvement of these traits. Comparatively higher heritability estimates for body conformation traits in the present study indicated towards the presence of genetic variability which might be due to the reason that linear type traits were not included in the selection criterion of Harnali sheep so far. High genetic variability in these traits noticeably indicated the scope of improvement in these body dimensions through selection. Breeding value estimates for different performance and body conformation traits pointed the variability between the genetic merit of individuals which can be exploited through selection for making improvement in the considered traits in Harnali sheep.

Enhancer promoter interactome and Mendelian randomization identify network of druggable vascular genes in coronary artery disease

Coronary artery disease (CAD) is a multifactorial disorder, which is partly heritable. Herein, we implemented a mapping of CAD-associated candidate genes by using genome-wide enhancer-promoter conformation (H3K27ac-HiChIP) and expression quantitative trait loci (eQTL). Enhancer-promoter anchor loops from human coronary artery smooth muscle cells (HCASMC) explained 22% of the heritability for CAD. 3D enhancer-promoter genome mapping of CAD-genes in HCASMC was enriched in vascular eQTL genes. By using colocalization and Mendelian randomization analyses, we identified 58 causal candidate vascular genes including some druggable targets (MAP3K11, CAMK1D, PDGFD, IPO9 and CETP). A network analysis of causal candidate genes was enriched in TGF beta and MAPK pathways. The pharmacologic inhibition of causal candidate gene MAP3K11 in vascular SMC reduced the expression of athero-relevant genes and lowered cell migration, a cardinal process in CAD. Genes connected to enhancers are enriched in vascular eQTL and druggable genes causally associated with CAD.

Genome-Wide Association Study of Body Conformation Traits by Whole Genome Sequencing in Dazu Black Goats

Simple SummaryBody conformation traits are economically important in the goat meat industry. Good growth performance in goats, including an accelerated growth rate, can improve carcass weight and meat yield. The identification of genetic variants associated with these traits provides a basis for the genetic improvement of growth performance. In this study, we measured six body conformation traits, including body height, body length, cannon circumference, chest depth, chest width, and heart girth. By a genome-wide association study of a Chinese meat goat breed, 53 significant single nucleotide polymorphisms and 42 candidate genes associated with these traits were detected. These findings improve our understanding of the genetic basis of body conformation traits in goats.Identifying associations between genetic markers and economic traits has practical benefits for the meat goat industry. To better understand the genomic regions and biological pathways contributing to body conformation traits of meat goats, a genome-wide association study was performed using Dazu black goats (DBGs), a Chinese indigenous goat breed. In particular, 150 DBGs were genotyped by whole-genome sequencing, and six body conformation traits, including body height (BH), body length (BL), cannon circumference (CC), chest depth (CD), chest width (CW), and heart girth (HG), were examined. In total, 53 potential SNPs were associated with these body conformation traits. A bioinformatics analysis was performed to evaluate the genes located close to the significant SNPs. Finally, 42 candidate genes (e.g., PSTPIP2, C7orf57, CCL19, FGF9, SGCG, FIGN, and SIPA1L) were identified as components of the genetic architecture underlying body conformation traits. Our results provide useful biological information for the improvement of growth performance and have practical applications for genomic selection in goats.

An algorithm-based approach for identification of most relevant linear traits for selecting high producing Murrah buffaloes

Selection of high producing dairy animals is important for dairy profitability and future breeding stock. Thefarmers have relied on physical characters for identification of milk producing ability in animals. In the presentstudy feature selection algorithm were implemented to identify most relevant traits for prediction of peak milk yieldin buffaloes. Based on data recorded from 259 lactating Murrah buffaloes, 14 different body and udder conformation traits, viz. Body Length (BL), Height at Wither (HW), Heart Girth (HG), Body Depth (BD), Paunch Girth (PG), Naval-Udder Distance (NUD), Udder Depth (UD), Rear Udder Height (RUH), Fore Teat Distance (FTD), RearTeat Distance (RTD), Fore Rear Teat Distance (FRTD), Teat Length (TL), Rump Width (RW) and Rear UdderWidth (RUW) were selected. Descriptive statistical analysis revealed that the correlation with peak yield is highestfor RUH, followed RUW, lactation number (LN), NUD, FRTD, HG, RW, RTD, UD, TL, PG, BL, BD, HW andFTD. Correlation-based feature selection in ‘WEKA’ software platform suggested that nine parameters have highcorrelation with peak yield – UD, NUD, RTD, FRTD, TL, RW, RUW, RUH and TL. The Multiple linear regression(MLR) was implemented using the linear regression function available under function classifier in WEKA. TwoRegression models (Model 1 and Model 2) were developed using all fifteen input parameters and with subset of 9input parameters suggested in ‘feature selection’. All models were trained and validated with 10-fold cross validation method. The performance of models developed for prediction peak milk yield was evaluated using the metrics correlation coefficient and root mean squared error (RMSE). Comparison of the performance evaluation matrices revealed that the Model 2 requiring lesser number of inputs is good enough in predicting peak yield with 0.8429 correlation coefficient and 2.16 root mean squared error.

The application of Legendre Polynomials to model muscularity and body condition score in primiparous Italian Simmental cattle

The aim of the present study was to develop a model to predict muscularity and body condition score (BCS) during the lactation of Italian Simmental dairy cows in Emilia Romagna herds. A total of 2656 Italian Simmental primiparous cows from 324 dairy herds were linear classified between 2002 and 2020. Lactation curves for muscularity and BCS were modelled for each cow using random regression model. The model included the fixed effects of age at linear scoring and days in milk modelled with a Legendre polynomial, and the random effects of herd-year of classification, cow and days in milk for each cow modelled with Legendre polynomials. The most parsimonious model included a fixed cubic Legendre polynomial and a random linear polynomial for cow effects. Results indicated that, on an average, BCS nadir was anticipated to that of muscularity, and, in both cases, this moment was around the lactation peak, when animals have the greatest nutrients requirement. After this period, both BCS and muscularity recovered up to post-partum levels. Moreover, after the 9 month of lactation, the absolute growth rate of muscularity and BCS was negative, suggesting that late-gestating cows could potentially enter a phase of body conformation loss. Results reported in the current research indicate that random regression using Legendre polynomials can be successfully employed to predict muscularity and BCS during the lactation of dairy cows. Highlights Modelling dairy cows’ muscularity and BCS allows to use these parameters as indicator traits for functionality in dairy cows. The use of prediction model of muscularity and BCS allows to understand the evolution of these conformation traits during the lactation. The analysis of muscularity and BCS allows to assess health and welfare status of dairy cows, which is essential to maximise production performances.

Comparison of a single-step with a multistep single nucleotide polymorphism best linear unbiased predictor model for genomic evaluation of conformation traits in German Holsteins

Genomic evaluation based on a single-step model uses all available data of phenotype, genotype, and pedigree; therefore, it should provide unbiased genomic breeding values with a higher correlation of prediction than the current multistep genomic model. Since 2019, a mixed reference population of cows and bulls has been applied to the routine multistep genomic evaluation in German Holsteins. For a fair comparison between the single-step and multistep genomic models, the same phenotype, genotype, and pedigree data were used. Because of its simple structure of the standard multitrait animal model used for German Holstein conventional evaluation, conformation traits were chosen as the first trait group to test a single-step SNP BLUP model for the large, genotyped population of German Holsteins. Genotype, phenotype, and pedigree data were taken from the official August 2020 conventional and genomic evaluation. Because of the same trait definition in national and multiple across-country evaluation for the conformation traits, deregressed multiple across-country evaluation estimated breeding value (EBV) of foreign bulls were treated as a new source of data for the same trait in the genomic evaluations. Due to a short history of female genotyping in Germany, the last 3 yr of youngest cows and bulls were deleted, instead of 4 yr, to perform a genomic validation. In comparison to the multistep genomic model, the single-step SNP BLUP model resulted in a higher correlation and greater variance of genomic EBV according to 798 national validation bulls. The regression of genomic prediction of the current, full evaluation on the earlier, truncated evaluation was slightly closer to 1 than the multistep model. For the validation bulls or youngest genomic artificial insemination bulls, correlation of genomic EBV between the 2 models was, on average, 0.95 across all the conformation traits. We did not find overprediction of young animals by the single-step SNP BLUP model for the conformation traits in German Holsteins.

A review of inbreeding depression in dairy cattle: current status, emerging control strategies, and future prospects.

Dairy cattle breeding has historically focused on relatively small numbers of elite bulls as sires of sons. In recent years, even if generation intervals were reduced and more diverse sires of sons could have been selected, genomic selection has not fundamentally changed the fact that a large number of individuals are being analyzed. However, a relatively small number of elite bulls are still siring those animals. Therefore inbreeding-derived negative consequences in the gene pool have brought concern. The detrimental effects of non-additive genetic changes such as inbreeding depression and dominance have been widely disseminated while seriously affecting bioeconomically important parameters because of an antagonistic relationship between dairy production and reproductive traits. Therefore, the estimation of benefits and limitations of inbreeding and variance of the selection response deserves to be evaluated and discussed to preserve genetic variability, a significant concern in the selection of individuals for reproduction and production. Short-term strategies for genetic merit improvement through modern breeding programs have severely lowered high-producing dairy cattle fertility potential. Since the current selection programs potentially increase long-term costs, genetic diversity has decreased globally as a consequence. Therefore, a greater understanding of the potential that selection programs have for supporting long-term genetic sustainability and genetic diversity among dairy cattle populations should be prioritized in managing farm profitability. The present review provides a broad approach to current inbreeding-derived problems, identifying critical points to be solved and possible alternative strategies to control selection against homozygous haplotypes while maintaining sustained selection pressure. Moreover, this manuscript explores future perspectives, emphasizing theoretical applications and critical points, and strategies to avoid the adverse effects of inbreeding in dairy cattle. Finally, this review provides an overview of challenges that will soon require multidisciplinary approaches to managing dairy cattle populations, intending to combine increases in productive trait phenotypes with improvements in reproductive, health, welfare, linear conformation, and adaptability traits into the foreseeable future.

Copy number variation of bovine DYNC1I2 gene is associated with body conformation traits in chinese beef cattle.

Previous, studies have shown that the dynein transporter compound has a role in diseases such as intellectual disability and cerebral malformations. However, the study of CNV in DYNC1I2 gene has not been reported. Q-PCR and data association analysis were used for DYNC1I2 gene copy in this study. In this study, blood samples were collected from five breeds of Chinese cattle (Qingchuan cattle, Xianan cattle, Yunling cattle, Pinan cattle and Guyuan cattle) for DYNC1I2 gene CNV type detection. SPSS 20.0 software and method of ANOVA were used to analyzed the association between types of CNV and growth traits. Results reveal that the distribution of different copy number types in different cattle breeds is different. Association analysis indicate that CNV of DYNC1I2 gene showed a positive effect in cattle growth: in XN cattle, individuals with deletion types showed better performance on height at hip cross (P<0.05); individuals with duplication types have better performance on body length (P<0.05) in PN cattle; individuals with deletion types was significantly correlated with chest width and Hucklebone width (P<0.05) in QC cattle; individuals with duplication types in Yunling cattle were better than the normal types, and there was a significant correlation between copy number variant and chest depth (P<0.05). The results showed that CNV markers closely related to cattle production traits were detected at DNA level, which could be used as an important candidate molecular marker for marker-assisted selection of growth traits in Chinese cattle, and provided a new research basis for genetics and breeding of Chinese beef cattle.

Distribution of Copy Number Variation in SYT11 Gene and Its Association with Growth Conformation Traits in Chinese Cattle.

Simple SummaryIt is known that many different breeds of cattle are widely distributed in China. However, due to a lengthy selection of draught direction, there are obvious shortcomings in Chinese cattle, such as less meat production, slow weight gain, poor meat quality, and a lack of specialized beef cattle breeds. Animal breeding heavily benefits from molecular technologies, among which molecular genetic markers were widely used to improve the economic traits of beef cattle. Because the copy number variation (CNV) involves a longer DNA sequence or even the entire functional gene, it may have a greater impact on the phenotype. Recent studies have indicated that CNVs are widespread in the Chinese cattle genome. By investigating the effects of CNVs on gene expression and cattle traits, we aim to find those genomic variations which could significantly affect cattle traits, and which could provide a basis for genetic selection and molecular breeding of local Chinese cattle.Currently, studies of the SYT11 gene mainly focus on neurological diseases such as schizophrenia and Parkinson’s disease. However, some studies have shown that the C2B domain of SYT11 can interact with RISC components and affect the gene regulation of miRNA, which is important for cell differentiation, proliferation, and apoptosis, and therefore has an impact on muscle growth and development in animals. The whole-genome resequencing data detected a CNV in the SYT11 gene, and this may affect cattle growth traits. In this study, CNV distribution of 672 individuals from four cattle breeds, Yunling, Pinan, Xianan, and Qinchuan, were detected by qPCR. The relationship between CNV, gene expression and growth traits was further investigated. The results showed that the proportion of multiple copy types was the largest in all cattle breeds, but there were some differences among different breeds. The normal type had higher gene expression than the abnormal copy type. The CNVs of the SYT11 gene were significantly correlated with body length, cannon circumference, chest depth, rump length, and forehead size of Yunling cattle, and was significantly correlated with the bodyweight of Xianan cattle, respectively. These data improve our understanding of the effects of CNV on cattle growth traits. Our results suggest that the CNV of SYT11 gene is a protentional molecular marker, which may be used to improve growth traits in Chinese cattle.

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.

Multivariate analysis of body weight, morphometric and thermo-physiological traits of indigenous pigs under tropical conditions

The study aimed at describing objectively the interdependence among the morphological and heat tolerance traits of Nigerian indigenous pigs and to predict body weight from conformation traits. Data on body weight, eight linear body measurements (BL, CG, CD, WH, RH, EL, SL and TL) and three thermo-physiological parameters were measured on 150 randomly selected pigs of three growth stages (piglets, growers and finishers) from February to December, 2020. The animals were managed in an extensive system in Plateau State, north central Nigeria. General linear model was used to study growth stage and sex effects including their interaction. Multivariate principal component analysis was used for the size, shape and heat tolerance determination while the animals were classified using canonical discriminant analysis. The stepwise regression was used for body weight prediction. The results showed that finishers had significantly higher (P&lt;0.05) body weight, body length, chest girth, chest depth, withers height, rump height, ear length, snout length and tail length, followed by growers while the least values were recorded in piglets. Pulse rate was not significantly different (P&gt;0.05) between piglets and finishers, although the latter had higher respiratory rate (39.48±0.53 vs. 39.90±0.53 vs. 36.77±0.75). However, rectal temperature was similar (P&gt;0.05) among the three pig categories. With the exception of tail length, sexual dimorphism was observed in all the morphometric traits with higher values recorded for males. However, the three thermo-physiological traits were not affected by sex (P&gt;0.05). BW was highly and positively correlated with most biometric traits (r = 0.80-0.93, 0.66-0.80 and 0.83-0.93; P&lt;0.01 for piglets, growers and finishers, respectively). Three principal components (PC1, PC2 and PC3) were extracted for optimal balance of the animals. Withers height, ear length and body weight were found to be the most discriminating variables to separate the pig categories. Classification results showed that 100% of piglets, 96.7% of growers and 96.7% of finishers were correctly assigned to their distinct populations. The present Information could be exploited in devising appropriate management and breeding programs for tropically adapted pigs in Nigeria.

Genetic analysis of biometric traits in Murrah buffaloes using Bayesian approach

The body conformation traits, which support higher production and longer productive life are very important to breed future dairy buffaloes. Bayesian multiple-trait analysis was performed in biometric traits of Murrah buffaloes to estimate the (co)variance components using an animal model and Gibbs sampling. The model included the fixed effects of parity, season of calving, period of calving, and age group at the time of recording of traits. Random effects included were additive genetic and residual effects. Posterior means of heritability distribution for body length (BL), height at wither (HW), rump width (RW), hip bone distance (HBD), rump slope (RS), brisket distance (BD), navel flap length (NFL) and average skin thickness (AST) were 0.45, 0.56, 0.56, 0.60, 0.48, 0.44, 0.53, and 0.53, respectively. Genetic correlation estimates ranged from -0.64 (RS and NFL) to 0.53 (HDB and HW) and residual correlation estimates ranged from -0.35 (RS and BL) to 0.57 (RS and HW). Results of the current study indicated that all considered linear type traits have a lot of genetic variabilities, which can be used for selection and genetic improvement of Murrah buffaloes in future.

Comparative analysis of inbreeding parameters and runs of homozygosity islands in 2 Italian autochthonous cattle breeds mainly raised in the Parmigiano-Reggiano cheese production region

Reggiana and Modenese are autochthonous cattle breeds, reared in the North of Italy, that can be mainly distinguished for their standard coat color (Reggiana is red, whereas Modenese is white with some pale gray shades). Almost all milk produced by these breeds is transformed into 2 mono-breed branded Parmigiano-Reggiano cheeses, from which farmers receive the economic incomes needed for the sustainable conservation of these animal genetic resources. After the setting up of their herd books in 1960s, these breeds experienced a strong reduction in the population size that was subsequently reverted starting in the 1990s (Reggiana) or more recently (Modenese) reaching at present a total of about 2,800 and 500 registered cows, respectively. Due to the small population size of these breeds, inbreeding is a very important cause of concern for their conservation programs. Inbreeding is traditionally estimated using pedigree data, which are summarized in an inbreeding coefficient calculated at the individual level (FPED). However, incompleteness of pedigree information and registration errors can affect the effectiveness of conservation strategies. High-throughput SNP genotyping platforms allow investigation of inbreeding using genome information that can overcome the limits of pedigree data. Several approaches have been proposed to estimate genomic inbreeding, with the use of runs of homozygosity (ROH) considered to be the more appropriate. In this study, several pedigree and genomic inbreeding parameters, calculated using the whole herd book populations or considering genotyping information (GeneSeek GGP Bovine 150K) from 1,684 Reggiana cattle and 323 Modenese cattle, were compared. Average inbreeding values per year were used to calculate effective population size. Reggiana breed had generally lower genomic inbreeding values than Modenese breed. The low correlation between pedigree-based and genomic-based parameters (ranging from 0.187 to 0.195 and 0.319 to 0.323 in the Reggiana and Modenese breeds, respectively) reflected the common problems of local populations in which pedigree records are not complete. The high proportion of short ROH over the total number of ROH indicates no major recent inbreeding events in both breeds. ROH islands spread over the genome of the 2 breeds (15 in Reggiana and 14 in Modenese) identified several signatures of selection. Some of these included genes affecting milk production traits, stature, body conformation traits (with a main ROH island in both breeds on BTA6 containing the ABCG2, NCAPG, and LCORL genes) and coat color (on BTA13 in Modenese containing the ASIP gene). In conclusion, this work provides an extensive comparative analysis of pedigree and genomic inbreeding parameters and relevant genomic information that will be useful in the conservation strategies of these 2 iconic local cattle breeds.

Fleckscore system of exterior evaluation as a more accurate indirect predictor of longevity in Slovak Simmental dairy cows

The goal of the work was to discover the influence of conformation traits evaluated by the Fleckscore system on the length of productive life of Slovak Simmental dairy cows. Evaluation of body conformation traits according to the Fleckscore system was performed on 3 452 cows. The relationship of individual traits to longevity was analysed using the Weibull proportional hazard model. The results confirmed that smaller and longer cows, which were well muscular and with a deeper body, had a lower risk of early culling than cows in the reference group. Hock angularity, pastern and hoof height scored with low or high marks were associated with an early culling of cows. In terms of the length of productive life, a slightly more elastic pattern is required. Cows with a deeper udder and a stronger and tighter fore udder attachment, which were also average in notching and height central ligament and centrally placed teats, reached a longer productive life.

Relationships of conformation traits with somatic cell score in Nubian goats

Records of 3716 Nubian goats from the United States (US) were analyzed to estimate relationships between fourteen conformation traits (CT) with lactation average somatic cell score (ASCS). To analyze ASCS, a mixed model was implemented. Linear and quadratic effects of CT traits, days in milk (DIM), and kidding age in months (KA) were considered as fixed covariates, and herd-year (HY) of kidding as a random effect. Correlation coefficients between CT traits and ASCS adjusted for HY and linear and [...]

Genetic analyses of metabolic body weight, carcass weight and body conformation traits in Nordic dairy cattle

Improving feed efficiency in dairy cattle by animal breeding has started in the Nordic countries. One of the two traits included in the applied Saved feed index is called maintenance and it is based on the breeding values for metabolic BW (MBW). However, BW recording based on heart girth measurements is decreasing and recording based on scales is increasing only slowly, which may weaken the maintenance index in future. Therefore, the benefit of including correlated traits, like carcass weight and conformation traits, is of interest. In this study, we estimated genetic variation and genetic correlations for eight traits describing the energy requirement for maintenance in dairy cattle including: first, second and third parity MBW based on heart girth measurements, carcass weight (CARW) and predicted MBW (pMBW) based on predicted slaughter weight, and first parity conformation traits stature (ST), chest width (CW) and body depth (BD). The data consisted of 21329 records from Finnish Ayrshire and 9780 records from Holstein cows. Heritability estimates were 0.44, 0.53, 0.56, 0.52, 0.54, 0.60, 0.17 and 0.26 for MBW1, MBW2, MBW3, CARW, pMBW, ST, CW and BD, respectively. Estimated genetic correlations among MBW traits were strong (>0.95). Genetic correlations between slaughter traits (CARW and pMBW) and MBW traits were higher (from 0.77 to 0.90) than between conformation and MBW traits (from 0.47 to 0.70). Our results suggest that including information on carcass weight and body conformation as correlated traits into the maintenance index is beneficial when direct BW measurements are not available or are difficult or expensive to obtain.

The Effect of Location and Parity in The Body, Udder Conformation and Milk Production Traits in Buffaloes

Seventy two adult lactating Iraqi buffaloes (Bubalus bubalis) were chosen randomly from two regions of Iraq, Baghdad (Abu Ghraib Ruminants Researches Station in the west of Baghdad, Iraq) and AL-Muthanna province (Alhilal township), during 2018/2019 lactating season. The effect of location and parity in the body, udder conformation and milk production traits were studied. The body conformation, body weight, udder measurements, and milk production traits were significant to high significant effected by both the location and the parity except there is the non-significant effect of location on body height at the shoulder, front teat diameter, rear teat length and rear teat diameter. Similarly non-significant effect of parity was observed on front teat diameter, rear teat length, distance between front and rear teats, fat%, lactose%, and SNF%.