TL;DR: Deposition of relatively less subcutaneous fat by goats than sheep adversely affects storage properties of meat, most importantly dehydration and cold-shortening and the magnitude of effect of castration on carcass fatness varies considerably with plane of nutrition.
TL;DR: Goats are spontaneously ovulating, polyoestrous animals as mentioned in this paper and the onset and length of the breeding season is dependent on various factors such as latitude, climate, breed, physiological stage, presence of the male, breeding system and specifically photoperiod.
TL;DR: The main target of treatment trials was to save the animal life and to prevent LSD complications and Eosinophilic intracytoplasmic inclusion bodies specific for LSD were detected by electron microscopy.
Abstract: The present study was conducted on 500 cattle of different breed in Giza governorate. Their age ranged from 1-7 years of different sexes. All suspected animals were clinically examined. The recoded lesions including the complicated cases in different age and sexes were described. The infected animals were classified according to the severity of clinical status into mild and severe forms. The severe form was recorded in all ages and both sexes in the frezian cattle and some of the native ones while the mild form was recorded in native cattle.The morbidity, mortality and case fatality rates of LSD among examined Egyptian cattle were 100%, 1.8%, and 1.8% respectively. Grossly lumpy skin lesions appeared as nodules 1 to 7 cm in diameter and occurred anywhere on the animal body. The hair stands erected over early skin lesions. The nodules involved the epidermis, dermis, and subcutaneous tissue and may even spread to the musculature. Histopathological examinations of lumpy skin disease revealed ballooning degeneration of stratum spinosum with microvesicles formation. Eosinophilic intracytoplasmic inclusion bodies specific for LSD were detected by electron microscopy. The main target of treatment trials was to save the animal life and to prevent LSD complications.
TL;DR: Investigating the behaviour profiles of 98 breeds and the behavioural differences among conventional breed groups based on historical utility and among genetic breed clusters found that two of the behaviour traits significantly differed both among the conventional and the genetic breed groups.
TL;DR: Small ruminant species such as sheep and goats are short-day breeders, which is a crucial factor affecting the offer of lambs and kids throughout the year, and an appropriate management of reproduction allows ewes and does to breed in the spring to increase the supply of product to the marketplace on a year-round basis.
Abstract: Small ruminant species such as sheep and goats are short-day breeders, which is a crucial factor affecting the offer of lambs and kids throughout the year. An appropriate management of reproduction allows ewes and does to breed in the spring to increase the supply of product to the marketplace on a year-round basis. Pharmaceutical control of reproduction is possible, usually through administration of hormones or analogues related to the natural estrous cycle, such as progesterone, prostaglandins, and/or melatonin.
TL;DR: The popular sire phenomenon is the most problematic breeding practice, since it has also led to the dissemination of a large number of inherited defects and the practice should be limited by taking measures such as restricting the number of litters per breeding animal.
Abstract: Pedigree analysis constitutes a classical approach for the study of the evolution of genetic diversity, genetic structure, history and breeding practices within a given breed As a consequence of selection pressure, management in closed populations and historical bottlenecks, many dog breeds have experienced considerable inbreeding and show (on the basis of a pedigree approach) comparable diversity loss compared to other domestic species This evolution is linked to breeding practices such as the overuse of popular sires or mating between related animals The popular sire phenomenon is the most problematic breeding practice, since it has also led to the dissemination of a large number of inherited defects The practice should be limited by taking measures such as restricting the number of litters (or offspring) per breeding animal
TL;DR: It was concluded that the breeds differed on various growth, production, egg and semen quality, and behavioral traits, but not on welfare traits, although female Aseel birds exhibited a greater fear response.
TL;DR: The present results indicate that the effects of the markers studied are breed-specific and cannot be extended to all Bos taurus breeds.
Abstract: The objectives of the study were to evaluate allelic frequencies and to test the association of polymorphisms in the calpastatin (CAST) and μ-calpain (CAPN1) genes with meat tenderness in 3 French beef breeds A total of 1,114 Charolais, 1,254 Limousin, and 981 Blonde d'Aquitaine purebred young bulls were genotyped for 3 SNP in the CAST gene and 4 SNP in the CAPN1 gene Two of these markers, 1 in each gene, can be found in Australian or American commercial genetic tests Others have previously been reported in American studies or are newly evidenced SNP The quantitative traits studied were Warner-Bratzler shear force and a tenderness score evaluated by trained sensory panels All the SNP were informative in the 3 breeds Associations of individual markers or haplotypes with traits were analyzed The results differed in the 3 breeds The G allele of a CAST marker (position 97574679 on Btau40) was found to exert a significant effect on the shear force (+018 phenotypic SD; RSD) and tenderness score (-022 RSD) in the Blonde d'Aquitaine breed In the same breed, this marker was associated with another CAST SNP (position 97576054 on Btau40) such that the GA haplotype appeared to be associated with tougher meat Two CAPN1 markers (positions 45221250 and 45241089 on Btau40) had a significant effect on both traits in the Charolais breed (from |011| to |025| RSD) In the same breed, these markers were associated with another CAPNI SNP (position 45219395 on Btau40) such that the ACA and AGG haplotypes appeared to be associated with a tender meat and a tougher meat, respectively Consequently, the present results indicate that the effects of the markers studied are breed-specific and cannot be extended to all Bos taurus breeds Further studies are also required to identify other more appropriate markers for French beef breeds
TL;DR: Between the Santa Inês groups, the group with white hair showed the better parameters for heat adaptation, while the brown hair group showed the lower heat adaptation when compared with another hair breed groups.
Abstract: The objective of this study was to evaluate and compare physical parameters in groups of sheep with different phenotypic characteristics in the Centre-west region of Brazil. Five groups of sheep, with nine animals per group, were selected, three groups of Santa Ines animals with different coat colours (white, brown and black), one group with crossbred animals (Santa Ines × Bergamasca) and one group with animals of the Bergamasca breed. The following traits were evaluated: coat thickness, number and length of hair, pigmentation level in the coat and the skin as well as the percentage area of sweats glands in the skin tissue, carried out by histological analysis. The number of hairs and the area of sweats glands were not significantly different between the evaluated groups. The Bergamasca breed showed low pigmentation of the skin and long hairs. The levels of pigmentation of the hair and of the skin were highly correlated. Between the Santa Ines groups, the group with white hair showed the better parameters for heat adaptation, while the brown hair group showed the lower heat adaptation when compared with another hair breed groups.
TL;DR: Three breeds (Fleckvieh, Holstein, and Jersey) were included in a reference population to assess the accuracy of prediction of genomic breeding values in single-breed validation populations, finding that using 2 other breeds in the reference was generally better than only 1 breed.
TL;DR: In this paper, the authors examined the feasibility and accuracy of using genotype data from the most prevalent bovine genome-wide association studies platform, the Illumina BovineSNP50 array (Illumina Inc., San Diego, CA), to estimate breed composition for individual breeds of cattle.
Abstract: Knowledge of breed composition can be useful in multiple aspects of cattle production, and can be critical for analyzing the results of whole genome-wide association studies currently being conducted around the world. We examine the feasibility and accuracy of using genotype data from the most prevalent bovine genome-wide association studies platform, the Illumina BovineSNP50 array (Illumina Inc., San Diego, CA), to estimate breed composition for individual breeds of cattle. First, allele frequencies (of Illumina-defined allele B) of SNP on the array for each of 16 beef cattle breeds were defined by genotyping a large set of more than 2,000 bulls selected in cooperation with the respective breed associations to be representative of their breed. With these breed-specific allele frequencies, the breed compositions of approximately 2,000 two-, three-, and four-way cross (of 8 breeds) cattle produced at the US Meat Animal Research Center were predicted by using a simple multiple regression technique or Mendel (http://www.genetics.ucla.edu/software/mendel) and their genotypes from the Illumina BovineSNP50 array, and were then compared with pedigree-based estimates of breed composition. The accuracy of marker-based breed composition estimates was 89% when using either estimation method for all breeds except Angus and Red Angus (averaged 79%), based on comparing estimates with pedigree-based average breed composition. Accuracy increased to approximately 88% when these 2 breeds were combined into an aggregate Angus group. Additionally, we used a subset of these markers, approximately 3,000 that populate the Illumina Bovine3K (Illumina Inc.), to see whether breed composition could be estimated with similar accuracy when using this reduced panel of SNP makers. When breed composition was estimated using only SNP in common with the Bovine 3K array, accuracy was slightly reduced to 83%. These results suggest that SNP data from these arrays could be used to estimate breed composition in most US beef cattle in situations where pedigree is not known (e.g., multiple-sire natural service matings, non-source-verified animals in feedlots or at slaughter). This approach can aid analyses that depend on knowledge of breed composition, including identification and adjustment of breed-based population stratification, when performing genome-wide association studies on populations with incomplete pedigrees. In addition, SNP-based breed composition estimates may facilitate fitting cow germplasm to the environment, managing cattle in the feedlot, and tracing disease cases back to the geographic region or farm of origin.
TL;DR: Low variation was found for all indices of the Creole goats, showing homogeneity between the groups of animals studied, and most of the functional indices are related to the milk biotype which is in agreement the possible origin of the breed from animals of the Iberian Peninsula and Canary Islands.
Abstract: In this work, linear body measures were taken and production indices calculated for 100 Cuban Creole goats and 100 crossbred goats in order to aid in the characterization of animal genetic resources in Cuba. Low variation was found for all indices of the Creole goats, showing homogeneity between the groups of animals studied. Most of the functional indices are related to the milk biotype which is in agreement the possible origin of the breed from animals of the Iberian Peninsula and Canary Islands. The crossbreds were more varied, mostly due to undesigned disorganized crossing. These data may help in identifying a commercial niche for the breed and contribute to in situ conservation of the Cuban Creole goat.
TL;DR: Results indicate that producers' trait preferences were heterogeneous except for body size in rams and mothering ability in ewes where nearly homogeneous preferences were investigated.
Abstract: Identification of breeding objective traits pertinent to specific production environments with the involvement of target beneficiaries is crucial to the success of a breed improvement program. A choice experiment was conducted in four locations representing different production systems and agro-ecologies that are habitat to four indigenous sheep breeds (Afar, Bonga, Horro and Menz) of Ethiopia with the objective of identifying farmers’/pastoralists’ preferences for sheep breeding traits. Following a synthesis of secondary information and diagnostic surveys, two communities per location consisting of 60 households each having at least four breeding ewes were identified. Producers’ priority attributes used in the choice sets were identified through in-depth production system studies conducted from December 2007 to March 2008. On the basis of prior information, four to seven attributes were used to design choice sets with different profiles in order to capture results that mimic real life of the different communities. The attributes and levels chosen for the sheep profile were as follows: body size (large/small), coat color (brown/white/black), tail type (good/bad) for both rams and ewes; horn (polled/horned) and libido (active/poor) for rams; and lambing interval (three lambings in 2 years/two lambings in 2 years time), mothering ability (good mother/bad mother), twinning rate (twin bearer/single bearer) and milk yield (two cups per milking/one cup per milking) for ewes. A fractional factorial design was implemented to construct the alternatives included in the choice sets. The design resulted in a randomized selection of 48 sheep profiles (24 sets) for both sexes, which were grouped into four blocks with six choice sets each. An individual respondent was presented with one of the four blocks to make his/her choices. Results indicate that producers’ trait preferences were heterogeneous except for body size in rams and mothering ability in ewes where nearly homogeneous preferences were investigated. In the pastoral production system, attention was given to coat color of both breeding rams and ewes, favoring brown and white colors over black. Ram libido influenced producers’ decisions in Bonga, Horro and Menz areas. The influence of milk yield and twinning on respondents’ decision making was high in Afar and Horro, respectively. Breeders in all areas attempt to combine production and reproduction traits as well as they can in order to maximize benefits from their sheep. The elicited measurable objective traits were used to design alternative community-based sheep breeding plans for the four indigenous sheep breeds in their production environments that have been implemented since.
TL;DR: It was found that an increase of SCC promulgated a progressive decline in the daily yield of milk, which was significantly true for the Polish Holstein-Friesian, and the interactions of a breed with increased SCC has indicated various levels of susceptibility to the increase in different breeds.
TL;DR: Goats’ milk from the autochthonous Greek breed (Prisca) provided the best antioxidant capacity and inhibitory properties on platelet aggregation of the milk samples tested.
TL;DR: Implementing large-scale selection schemes that implement emerging new information on the sheep genome, overcoming threats of inbreeding depression, and further breeding for high uterine capacity are the new breeding goals for the Awassi, Assaf, and their derivatives.
Abstract: The Local Awassi, a triple-purpose breed for meat, milk, and carpet–wool production, is a low-prolific, hardy breed that is well adapted to the unfavorable conditions of the Middle East, where it is managed under traditionally extensive to semi-extensive conditions. Breeding work with the Awassi has included within-breed selection, crossbreeding, and gene introgression. Those efforts resulted in a variety of Awassi-derived genotypes that successfully occupy semi-intensive as well as intensive production systems. Thus, within-breed selection resulted in development of the “Improved Awassi”—a dairy-type Awassi strain which, under intensive management, produces over 500 l milk/ewe annually; crossbreeding with the East Friesian breed led to the development of the Assaf dairy breed, which exceeds the Improved Awassi in prolificacy and in year-round breeding activity, and introgression of the B allele of the FecB locus into the Awassi and Assaf breeds resulted in the formation of the prolific Afec Awassi and Afec Assaf strains, with prolificacies of 1.9 and 2.5 lambs born per ewe lambing, respectively. Advanced molecular genetics tools have enabled a better understanding of how the Awassi breed was formed during domestication and have uncovered differences in its genetic structure compared to other breeds. Implementing large-scale selection schemes that implement emerging new information on the sheep genome, overcoming threats of inbreeding depression, and further breeding for high uterine capacity are the new breeding goals for the Awassi, Assaf, and their derivatives.
TL;DR: Although breed, age, and SC did not significantly affect the prevalence of head or midpiece defects, morphologically normal or abnormal sperm, tail defects were more prevalent in Angus and Hereford bulls compared with other breeds.
Abstract: The objectives of this study were to determine the associations of breed, age, and scrotal circumference (SC), and their interaction, on the prevalence of sperm abnormalities in beef bulls in Alberta, Canada, and the percentage of satisfactory potential breeders identified during breeding soundness examination solely due to normal sperm morphology. Eosin-nigrosin stained semen smears and evaluation reports of 1642 bull breeding soundness evaluations were procured from 6 veterinary clinics in Alberta. Sperm morphology was determined for at least 100 sperm per bull. The most common defects were detached head [4.86% ± 5.71%; mean ± standard deviation (s)], distal midpiece reflex (6.19% ± 9.13%), and bent tail (1.01% ± 1.54%). Although breed, age, and SC did not significantly affect the prevalence of head or midpiece defects, morphologically normal or abnormal sperm, tail defects were more prevalent in Angus and Hereford bulls compared with other breeds. Overall, solely on the basis of sperm morphology, 1363 (83.0%) bulls were classified as satisfactory potential breeders and the remainder 279 (17.0%) as unsatisfactory (> 30% abnormal sperm, > 20% defective heads, or both). Although not significantly different, the breed with the highest percentage of satisfactory potential breeders was Limousin (90.6%) and the lowest was Hereford (78.8%). That 17% of bulls subjected to breeding soundness evaluation were designated as unsatisfactory solely on the basis of sperm morphology highlights its importance.
TL;DR: Simulation results confirmed that the popular sire practice leads to a dissemination of genetic disorders, and under a realistic scenario, regarding the imbalance in the use of sires, the dissemination risk was 4.4 times higher than under random mating conditions.
Abstract: On the basis of simulations and genealogical data of ten dog breeds, three popular mating practices (popular sire effect, line breeding, close breeding) were investigated along with their effects on the dissemination of genetic disorders. Our results showed that the use of sires in these ten breeds is clearly unbalanced. Depending on the breed, the effective number of sires represented between 33% and 70% of the total number of sires. Mating between close relatives was also found to be quite common, and the percentage of dogs inbred after two generations ranged from 1% to about 8%. A more or less long-term genetic differentiation, linked to line breeding practices, was also emphasized in most breeds. F(IT) index based on gene dropping proved to be efficient in differentiating the effects of the different mating practices, and it ranged from -1.3% to 3.2% when real founders were used to begin a gene dropping process. Simulation results confirmed that the popular sire practice leads to a dissemination of genetic disorders. Under a realistic scenario, regarding the imbalance in the use of sires, the dissemination risk was indeed 4.4 times higher than under random mating conditions. In contrast, line breeding and close breeding practices tend to decrease the risk of the dissemination of genetic disorders.
TL;DR: Opportunities to minimise the risk of boar taint in entire male pigs by carefully selecting a combination of breed and slaughter weight are indicated.
Abstract: Pietrain (P), Large White (LW) and Belgian Landrace stress negative (BN) boars were slaughtered at 50, 70, 90 or 110 kg live weight to investigate breed differences and the effect of slaughter weight on boar taint prevalence. Boar taint was quantified by four different methodologies: sensory evaluation of neckfat heated with a hot iron in the slaughterhouse, sensory evaluation of meat by consumer panels, sensory evaluation of fat and meat by expert panels and laboratory analysis of indole, skatole and androstenone in backfat. Skatole levels in backfat were significantly higher for LW and BN than for P boars. The androstenone levels and the hot iron method revealed a significant interaction between breed and slaughter weight. On the other hand, experts detected an effect of weight on the androstenone odour perception, which was significantly higher in fat from boars slaughtered at 90 kg compared with 50 kg, and significantly higher in meat from boars slaughtered at 110 kg compared with 50 kg. Consumers did not detect differences in the sensory characteristics among breeds or slaughter weight. These results indicate opportunities to minimise the risk of boar taint in entire male pigs by carefully selecting a combination of breed and slaughter weight. Along with the optimal slaughter weight, the effectiveness of reducing boar taint by lowering slaughter weight appeared to be breed dependent.
TL;DR: The population structure of 302 randomly selected West African Dwarf and Red Sokoto goats was examined using multivariate morphometric analyses to make the case for conservation, rational management and genetic improvement of these two most important Nigerian goat breeds.
Abstract: The population structure of 302 randomly selected West African Dwarf (WAD) and Red Sokoto (RS) goats was examined using multivariate morphometric analyses. This was to make the case for conservation, rational management and genetic improvement of these two most important Nigerian goat breeds. Fifteen morphometric measurements were made on each individual animal. RS goats were superior (P < 0.05) to the WAD for the body size and skeletal proportions investigated. The phenotypic variability between the two breeds was revealed by their mutual responses in the principal components. While four principal components were extracted for WAD goats, three components were obtained for their RS counterparts with variation in the loading traits of each component for each breed. The Mahalanobis distance of 72.28 indicated a high degree of spatial racial separation in morphology between the genotypes. The Ward’s option of the cluster analysis consolidated the morphometric distinctness of the two breeds. Application of selective breeding to genetic improvement would benefit from the detected phenotypic differentiation. Other implications for management and conservation of the goats are highlighted.
TL;DR: Commercially important breeds were found to have substantial variation, which should enable breeders to proceed, unencumbered by genetic diversity concerns, with selection strategies that maximize profit.
Abstract: Understanding existing levels of genetic diversity of sheep breeds facilitates in situ and ex situ conservation activities. A comprehensive evaluation of US sheep breeds has not been previously performed; therefore, we evaluated the genetic diversity among and within 28 US sheep breeds. Both major and minor breeds were included in the analysis and consisted of 666 animals from 222 producers located in 38 states. The level of within-breed genetic diversity was variable and not dependent upon status of a breed as a major or minor breed. Bayesian cluster analysis indicated the breeds were grouped more by physiological differences (meat vs. wool production) rather than geographic origin. Results suggest several actionable items to improve in situ and ex situ conservation. The results clearly identify breeds in need of increased in situ and ex situ management (e.g., Hog Island and Karakul) and allow several suggestions for in situ management of flocks. Conversely, several of the breeds appear genetically similar and therefore require less emphasis on collecting germplasm samples for the gene bank. Commercially important breeds (e.g., Rambouillet and Suffolk) were found to have substantial variation, which should enable breeders to proceed, unencumbered by genetic diversity concerns, with selection strategies that maximize profit.
TL;DR: Differences in milk fat composition can be used in strategies to breed for milk with a FA profile more favorable for human health, and support the relevance of safeguarding the local Dutch breeds.
TL;DR: Female calves had a longer gestation length, had a greater incidence of calving difficulty, had greater mortality to weaning, were heavier, and grew faster than female calves, and sire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
Abstract: The objective of this study was to characterize breeds representing diverse biological types for birth and weaning traits in crossbred cattle. Gestation length, calving difficulty, percentage of unassisted calving, percentage of perinatal survival, percentage of survival from birth to weaning, birth weight, BW at 200 d, and ADG were measured in 2,500 calves born and 2,395 calves weaned. Calves were obtained by mating Hereford, Angus, and MARC III (one-fourth Hereford, one-fourth Angus, one-fourth Pinzgauer, and one-fourth Red Poll) mature cows to Hereford or Angus (British breed), Brahman, Tuli, Boran, and Belgian Blue sires. Calves were born during the spring seasons of 1992, 1993, and 1994. Sire breed was significant for all traits (P < 0.002). Offspring from British breeds and the Belgian Blue breed had the shortest gestation length (285 d) when compared with progeny from other sire breeds (average of 291 d). Calving difficulty was greater in offspring from Brahman sires (1.24), whereas the offspring of Tuli sires had the least amount of calving difficulty (1.00). Offspring from all sire breeds had similar perinatal survival and survival from birth to weaning (average of 97.2 and 96.2%, respectively), with the exception of offspring from Brahman sires, which had less (92.8 and 90.4%, respectively). Progeny of Brahman sires were heaviest at birth (45.7 kg), followed by offspring from British breed, Boran, and Belgian Blue sires (average of 42.4 kg). The lightest offspring at birth were from Tuli sires (38.6 kg). Progeny derived from Brahman sires were the heaviest at 200 d (246 kg), and they grew faster (1.00 kg/d) than offspring from any other group. The progeny of British breeds and the Belgian Blue breed had an intermediate BW at 200 d (238 kg) and an intermediate ADG (average of 0.98 kg/d). The progeny of Boran and Tuli sires were the lightest at 200 d (227 kg) and had the least ADG (0.93 kg/d). Male calves had a longer gestation length, had a greater incidence of calving difficulty, had greater mortality to weaning, were heavier, and grew faster than female calves. Sire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
TL;DR: The seasonal variation in the sexual activity of ovine and caprine species with special regard to local Spanish sheep and goats breeds is described, how the photoperiod regulates their annual reproductive cycle is examined, and a number of strategies that can be used to induce and synchronise ovulation outside the natural breeding season are discussed.
Abstract: Sheep and goat breeds from subtropical, middle and high latitudes show seasonal changes in reproductive activity. In general, the breeding season starts in autumn and ends in winter, with anoestrus in spring/summer. An endogenous circannual rhythm driven and synchronised by the annual photoperiod cycle regulates the onset and offset of the breeding season. However, the timing and duration of the breeding season can be affected by interactions between the photoperiod and factors such as breed, geographical origin, nutritional and lactational status, social interactions, and the season of parturition. Seasonality in reproduction is naturally accompanied by variation in the availability and price of meat, milk and cheese over the year, affecting the economy of farmers, consumers and the food industry alike. The control of reproduction outside the normal breeding season by inducing and synchronizing oestrus and ovulation plus the use of artificial insemination and/or natural mating would help ensure the year-round availability of products. This review describes the seasonal variation in the sexual activity of ovine and caprine species with special regard to local Spanish sheep and goats breeds, examines how the photoperiod regulates their annual reproductive cycle, and discusses a number of strategies that can be used to induce and synchronise ovulation outside the natural breeding season.
TL;DR: It is suggested that the two sheep breeds have disparate immune responses following infection with the parasite and that γδ+ T cells in association with eosinophils may play a hitherto unrecognised role in modulating fecundity in H. contortus adult female parasites.
TL;DR: It is demonstrated that a relationship exists between parturition duration, neonatal viability and behavior, and acid-base balance values in single- and twin-born lambs, suggesting that birth asphyxia is an important risk factor in perinatal lamb mortality.
Abstract: The objective of the present study was to test the hypothesis that parturition duration is related to birth asphyxia in lambs and that asphyxia affects newborn lamb viability and vigor. Two sire and dam genotypes (Texel: TX; Polwarth: PW) and their crosses were represented in the study. Eighty lambs (25 PW sire × PW dam, 13 TX × TX, 25 TX × PW, and 17 PW × TX) born to 69 grazing ewes were used. At birth, the log₁₀ length of the second stage of parturition, birth weight, placental weight, and several body measurements were recorded on all lambs, and jugular blood samples were analyzed with the i-Stat Portable Clinical Analyzer (Abbott, Montevideo, Uruguay). A modified Apgar viability score at birth and lamb behavior during their first hour of life were recorded. Brain weight, muscle:bone ratio, and bone density were recorded in 20 male lambs (5 from each breed group) that were euthanized and dissected 24 h after birth. Data were analyzed by linear regression, least squares ANOVA, and ordinal and binary logistic regressions. Mean blood gas and acid-base variables were 7.21 ± 0.09 for pH, 18.4 ± 9.8 mmHg for partial pressure of oxygen, 53 ± 12.5 mmHg for partial pressure of carbon dioxide, and -4 ± 5.1 mmol/L for extracellular fluid base excess. Parturition duration increased with birth weight (P < 0.001) and was shorter in TX ewes (P < 0.001), female lambs (P < 0.05), twins (P < 0.09), and twin females (sex × litter size interaction, P < 0.02). Twenty-six (32.9%) lambs were born asphyxiated (pO₂ < 10 mmHg or pH <7.1). Parturition duration increased the risk of asphyxia (P < 0.001), decreased the viability score (P < 0.001), and increased the latency to suckle the udder (P < 0.05). Twin-born lambs presented at birth a 16-fold greater risk of asphyxia (P < 0.01) and reduced placental efficiency (P < 0.05). Texel-sired lambs appeared immature at birth, with less bone density (P < 0.05), smaller brain (P < 0.05), shorter forelimbs (P < 0.05), greater anterior (P < 0.001) and posterior (P < 0.05) neck circumference, and greater muscle:bone ratio (P < 0.05). Immaturity may explain greater TX biotype survival. Together these results demonstrate that a relationship exists between parturition duration, neonatal viability and behavior, and acid-base balance values in single- and twin-born lambs, suggesting that birth asphyxia is an important risk factor in perinatal lamb mortality.
TL;DR: Boer goats were not superior to Kiko or Spanish for preweaning kid performance when semi-intensively managed on humid, subtropical pasture and Kiko should be a preferred breed and to a lesser extent Spanish for enhancing birth to weaning kidperformance.
Abstract: Boer, Kiko, and Spanish meat goats were semi-intensively managed in a complete 3-breed diallel mating scheme to evaluate genetic effects on preweaning kid performance. Over a 6-yr period, 1,547 kids were born in March and May with 1,173 kids raised by their dams to weaning at 3 mo of age. March-born kids were lighter (P 0.10). Maternal Boer effects were negative (P 0.5) for preweaning ADG or weaning weight. Heterosis for birth weight was exhibited (P < 0.01) for each pair of breed crosses, but only between Boer and Kiko for ADG and weaning weight. Kiko and Spanish dams had greater (P < 0.01) preweaning kid survival rates than Boer dams, but the former 2 did not differ (P = 0.72). Significant genetic variation was observed between meat goat breeds for kid performance to weaning. Maternal breed effects were more influential than direct breed effects. Boer goats were not superior to Kiko or Spanish for preweaning kid performance when semi-intensively managed on humid, subtropical pasture. Kiko should be a preferred breed and to a lesser extent Spanish for enhancing birth to weaning kid performance. Findings of this study emphasize the importance of proper doe breed selection in achieving desired kid performance to weaning in meat goats.
TL;DR: The main factors involved in gestational length in broodmares were the mating period within the breeding season, climate, year of breeding, photoperiod, and treatment with artificial light.
TL;DR: The Bayesian clustering approach suggested poor breed differentiation in the north-western arid and semi-arid region when compared to the breeds from the eastern and southern peninsular regions and moderate discrimination between the indigenous sheep breeds was revealed.
Abstract: Summary
This study attempts to provide a comprehensive insight into the prevailing genetic status of Indian sheep breeds using microsatellite markers. Seventeen Indian sheep breeds from 3 agroecological zones were analysed using a panel of 25 microsatellite markers. All of the sheep breeds investigated were genetically diverse, as evident from the high allele (>6) and gene (>0.6) diversity values. The gene diversity values for all breeds ranged from 0.621 to 0.780. The within-population heterozygote deficit (FIS) varied from −0.098 to 0.234, reflecting significant levels for 12 of the 17 breeds investigated. The average genetic differentiation between all breeds (FST) was 11.1%, revealing moderate discrimination between the indigenous sheep breeds. The genetic distance and principal component analysis revealed a separation of sheep breeds based on geographical propinquity. The Bayesian clustering approach suggested poor breed differentiation in the north-western arid and semi-arid region when compared to the breeds from the eastern and southern peninsular regions. The observed results mirror the divergent management strategies in the different agroecological regions, lack of specific selection policies, and intermixing of breeds in close proximity. Immediate steps to curb the intermixing and erosion of breed purity for some of these breeds need to be implemented, for example, by introducing measures like making proven rams available and ensuring their frequent exchange between flocks. The data generated here provides valuable information about the genetic structure of the 17 Indian sheep breeds and this can be used for designating priorities for their conservation.
TL;DR: The Boran bucks were found to have superior body and reproduction traits and SC, which is easily measured in the live animal and predicted to be the best indicator of testicular and epididymal measurements.