RESUMO
Climate change increases the frequency and intensity of extreme weather events that negatively impact wildlife, from individuals to whole ecosystems1. In polar environments, such events include heat waves2, anomalous sea ice concentrations3 and storms4. Polar seabirds are adapted to withstand harsh conditions, and although extreme weather events affect their breeding success and other demographic rates, they are thought to affect only a part of the population. Complete breeding failure of an entire population due to extreme environmental conditions is rarely observed5. Here we report how exceptional storm activity in Dronning Maud Land (DML), Antarctica, in the austral summer of 2021/2022 caused almost complete and large-scale breeding failures of the area's three most common seabird species - Antarctic petrel (Thalassoica antarctica), Snow petrel (Pagodroma nivea) and South polar skua (Stercorarius maccormicki).
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Charadriiformes , Ecossistema , Humanos , Animais , Regiões Antárticas , Aves , CruzamentoRESUMO
Long-term parental separation can lead to altered behavioral and physical development in human children. Rodent models are popular for studying parent-child separation, and several studies have found that maternal separation leads to chronic changes in the endocrine stress response. However, while human children are generally raised by multiple caregivers, most rodent studies utilize solitary breeding species. Therefore, we used degus (Octodon degus) as a model for studying human parental separation, as these rodents practice plural breeding and communal care. In this study, we cross-fostered degu litters at different ages (post-natal day [PND] 2, 8, and 14) to test the hypotheses that fostering affects offspring stress hormone levels in both the short- and long-term and that these impacts differ depending on the age at which offspring are fostered. We found that fostering had long-term effects, as fostered offspring had higher stress-induced cortisol levels and weaker cortisol negative feedback than non-fostered offspring at weaning age (PND28). We also found that the timing of fostering mattered, as degus fostered at PND8 had higher baseline cortisol levels the day after fostering, while degus fostered at PND2 had higher stress-induced cortisol levels at weaning. These data suggest that long-term cross-fostering has enduring impacts on the endocrine stress response in degus, therefore making them a useful model organism for investigating impacts of parental separation in humans.
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Hidrocortisona , Octodon , Animais , Humanos , Hidrocortisona/farmacologia , Roedores , Octodon/fisiologia , Privação Materna , CruzamentoRESUMO
Seoul orthohantavirus (SEOV) is a rat-associated zoonotic pathogen with an almost worldwide distribution. In 2019, the first autochthonous human case of SEOV-induced hemorrhagic fever with renal syndrome was reported in Germany, and a pet rat was identified as the source of the zoonotic infection. To further investigate the SEOV reservoir, additional rats from the patient and another owner, all of which were purchased from the same vendor, were tested. SEOV RNA and anti-SEOV antibodies were found in both of the patient's rats and in two of the three rats belonging to the other owner. The complete coding sequences of the small (S), medium (M), and large (L) segments obtained from one rat per owner exhibited a high sequence similarity to SEOV strains of breeder rat or human origin from the Netherlands, France, the USA, and Great Britain. Serological screening of 490 rats from breeding facilities and 563 wild rats from Germany (2007-2020) as well as 594 wild rats from the Netherlands (2013-2021) revealed 1 and 6 seropositive individuals, respectively. However, SEOV RNA was not detected in any of these animals. Increased surveillance of pet, breeder, and wild rats is needed to identify the origin of the SEOV strain in Europe and to develop measures to prevent transmission to the human population.
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Vírus Seoul , Zoonoses , Humanos , Animais , Ratos , Europa (Continente) , Cruzamento , Éxons , França , RNA , Vírus Seoul/genéticaRESUMO
Autoimmune subepidermal blistering diseases (AISBDs) are rare skin disorders of animals that were first identified in dogs but several AISBDs are now recognised in other companion animal species. Most AISBDs in animals are homologues of the human diseases and are thought to share similar pathomechanisms of epidermal and/or mucosal blister formation caused by autoantibodies targeting structural proteins of the basement membrane zone (BMZ). Disruption of their structural function by the autoantibodies and/or recruited inflammation leads to BMZ fragility, which presents clinically as vesicles, bullae and, later, deep erosions and ulcers. Canine AISBDs are the best characterised, particularly the more common variants such as mucous membrane pemphigoid (48%), epidermolysis bullosa acquisita (EBA) (26%), and bullous pemphigoid (10%). Exceedingly rare AISBDs in the dog are junctional EBA, mixed AISBD, type-1 bullous systemic lupus erythematosus, linear IgA dermatosis, and pemphigus gestationis. The diagnosis of a specific AISBD is made by combining the clinical features (breed, age, lesion distribution) with histological evidence of subepithelial clefting, but not all AISBDs can be differentiated in this manner and specialised immunological testing is required. This latter, unfortunately, is not readily available and, therefore, the specific AISBD diagnosis often remains unconfirmed. While this limits further understanding of these diseases, it does not prevent clinicians from treating their patients, as the treatment approaches are similar for the different AISBDs in dogs. This review primarily focuses on canine AISBDs, the species for which these diseases have been best characterised, and shorter descriptions of variants in other species are also provided.
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Doenças do Cão , Pênfigo , Humanos , Animais , Cães , Pele , Pênfigo/veterinária , Epiderme , Autoanticorpos , Cruzamento , Doenças do Cão/diagnósticoRESUMO
Chickens are believed to have inhabited the Hawaiian island of Kauai since the first human migrations around 1200AD, but numbers have peaked since the tropical storms Iniki and Iwa in the 1980s and 1990s that destroyed almost all the chicken coops on the island and released large numbers of domestic chickens into the wild. Previous studies have shown these now feral chickens are an admixed population between Red Junglefowl (RJF) and domestic chickens. Here, using genetic haplotypic data, we estimate the time of the admixture event between the feral population on the island and the RJF to 1981 (1976-1995), coinciding with the timings of storm Iwa and Iniki. Analysis of genetic structure reveals a greater similarity between individuals inhabiting the northern and western part of the island to RJF than individuals from the eastern part of the island. These results point to the possibility of introgression events between feral chickens and the wild chickens in areas surrounding the Koke'e State Park and the Alaka'i plateau, posited as two of the major RJF reservoirs in the island. Furthermore, we have inferred haplotype blocks from pooled data to determine the most plausible source of the feral population. We identify a clear contribution from RJF and layer chickens of the White Leghorn (WL) breed. This work provides independent confirmation of the traditional hypothesis surrounding the origin of the feral populations and draws attention to the possibility of introgression of domestic alleles into the wild reservoir.
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Galinhas , Hibridização Genética , Animais , Humanos , Galinhas/genética , Havaí , Ilhas , CruzamentoRESUMO
This article addresses the underrepresentation of Indigenous perspectives in animal sciences by challenging the exclusive use of Western scientific paradigms in research and education. Because of the systematic exclusion of Indigenous peoples, Indigenous perspectives have rarely been represented through empirical study, leading us to believe this is a key reason for the underrepresentation of Native people in these fields. We conducted a literature review, searching for Indigenous contributions in animal sciences and finding a handful of articles in three areas: human-animal bonds, genetic testing and breeding programs, and Traditional Ecological Knowledge. Given the interconnected paradigm of Indigenous worldviews, we suggest that the ongoing siloes of scientific disciplines and the hierarchy of methodology contribute to the dearth of Indigenous perspectives. We suggest increased support for proper tribal consultation, contextualization of the history of research in Native communities, and the creation of scholarly spaces to support these conversations.
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Criação de Animais Domésticos , Povos Indígenas , Animais , Humanos , Cruzamento , Vínculo Humano-Animal , Conhecimento , EcologiaRESUMO
Fungal aerosols are a vital environmental hazard factor impeding the development of the rabbit breeding industry and threatening public health. This study aimed to determine fungal abundance, diversity, composition, diffusion, and variability in aerosols in rabbit breeding environments. Twenty PM2.5 filter samples were collected from five sampling sites (i.e. En5, In, Ex5, Ex15, and Ex45) in a modern rabbit farm in Linyi City, China. Fungal component diversity at the species level was analyzed in all samples using third-generation sequencing technology. Results revealed that fungal diversity and community composition in PM2.5 significantly differed across different sampling sites, and different pollution levels. The highest concentrations of PM2.5 and fungal aerosols (i.e., 102.5 µg/m3 and 18.8 × 103 CFU/m3, respectively) were found at Ex5, and these concentrations were found to decrease as the distance from the exit increased. However, no significant correlation was observed between the internal transcribed spacer (ITS) gene abundance and overall PM2.5 levels, except for Aspergillus ruber and Alternaria eichhorniae. Although most fungi are not pathogenic to humans, zoonotic pathogenic microorganisms that cause pulmonary aspergillosis (e.g., Aspergillus ruber) and invasive fusariosis (e.g., Fusarium pseudensiforme) were observed. The relative abundance of A. ruber was higher at Ex5 than that at In, Ex15, and Ex45 (p < 0.01), and the relative abundance of the fungal species decreased with an increase in distance from the rabbit houses. Moreover, four potential novel strains of Aspergillus ruber were discovered, with 82.9%-90.3% of the nucleotide and amino acid sequences similar to those of reference strains. This study highlights the importance of rabbit environments as a source in shaping fungal aerosol microbial communities. To the best of our knowledge, this is the first study to uncover the initial characteristics of fungal biodiversity and dispersion of PM2.5 in rabbit breeding environments, contributing to infectious disease control and prevention in rabbits.
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Poluentes Atmosféricos , Material Particulado , Humanos , Animais , Coelhos , Material Particulado/análise , Fungos , Microbiologia do Ar , Tecnologia , Aerossóis/análise , Cruzamento , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análiseRESUMO
In the present study, the re-sequencing of our previous whole-genome sequencing (WGS) for selected individuals of Dazu-black goat (DBG) and Inner-Mongolia Cashmere goat (IMCG) breeds was used to detect and compare the differentiation in Indels depending on the reference genome of goat. Then, three selected candidate Indels rs668795676, rs657996810, and rs669452874 of the three genes SUFU, SYCP2L and GLIPR1L1, respectively, have been chosen, based on the results of prior GWAS across the genome, and examined for their association with body weight and dimensions (body height, body length, heart girth, chest width, cannon circumference, and chest depth) by kompetitive allele specific PCR assay for 342 goats from the three studied goat breeds (DBG, n = 203; â99, â104), IMCG (n = 65; 15â, 50â), and Hechuan white goat (HWG, n = 74; 34â, 40â) breeds. The analysis of 192.747 Gb WGS revealed an average 334,151 Indels in the whole genome of DBG and IMCG breeds. Chromosome 1 had a maximum number of mutations (Indels) of 58,497 and 55,527 for IMCG and DBG, respectively, while chromosome 25 had the least number of mutations of 15,680 and 16,103 for IMCG and DBG, respectively. The majority of Indels were either Ins or Del of short fragments of 1-5 bp, which covered 79.06 and 71.78% of the total number of Indels mutations in IMCG and DBG, respectively. Comparing the differences of Indels between the studied goat breeds revealed 100 and 110 unique Indels for IMCG and DBG, respectively. The Indels loci in the intron region were unique for both studied goat breeds which were related to 30 and 38 candidate genes in IMCG and DBG, respectively, including SUFU, SYCP2L, and GLIPR1L1 genes. Concerning rs669452874 locus, body height and body length of Del/Del genotype in DBG were significantly higher (P < 0.05) than that of Ins/Del genotype, while body height and body length of Del/Del genotype in IMCG were significantly higher (P < 0.01) than those of Ins/Ins genotype, whereas body height and body length and heart girth of Del/Del genotype in HWG were significantly higher (P < 0.01) than those of the Ins/Del and Ins/Ins genotypes. Thus, Del/Del genotype of rs669452874 locus can be used as a candidate molecular marker related to the body dimensions in the studied goat breeds.
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Cabras , Mutação INDEL , Animais , Alelos , Genoma , Genótipo , Cabras/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , CruzamentoRESUMO
Although most birds are considered to be at least partially monogamous, molecular evidence continues to uncover that many species can have multiple sexual mates. Many species of Waterfowl (Order Anseriformes) consistently deploy alternative breeding strategies, and although cavity nesting species have been well studied, few attempts to understand rates of alternative breeding strategies exist in the Anatini tribe. Here, we assay mitochondrial DNA and thousands of nuclear markers across 20 broods of American black ducks (Anas rubripes; "black duck") that included 19 females and 172 offspring to study population structure as well as types and rates of secondary breeding strategies in coastal North Carolina. First, we report high levels of relatedness among nesting black ducks and offspring and while 17 (of 19) females were of pure black duck descent, three were found to be black duck x mallard (A. platyrhynchos) hybrids. Next, we evaluated for mismatched mitochondrial DNA and paternity identities across each female's clutch to determine types and frequency of alternative or secondary breeding strategies. Although we report that nest parasitism occurred in two nests, 37% (7 of 19) of the sampled nests were multi-paternal as a result of extra-pair copulation. In addition to being part of a mix of strategies used to increase fecundity by successfully breeding females, we posit nest densities providing easier alternative mate access for males also explains high rates of extra-pair copulation among our sampled black ducks. Ultimately, however, while some proportion of females of many species engage in forms of secondary breeding strategies, we conclude that the decision to do so appears to be seasonally flexible for each individual.
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Cruzamento , Patos , Humanos , Animais , Masculino , Feminino , North Carolina , Aves , Reprodução , Comportamento de NidaçãoRESUMO
Sow farrowing is an important part of pig breeding. The accurate and effective early warning of sow behaviors in farrowing helps breeders determine whether it is necessary to intervene with the farrowing process in a timely manner and is thus essential for increasing the survival rate of piglets and the profits of pig farms. For large pig farms, human resources and costs are important considerations in farrowing supervision. The existing method, which uses cloud computing-based deep learning to supervise sow farrowing, has a high equipment cost and requires uploading all data to a cloud data center, requiring a large network bandwidth. Thus, this paper proposes an approach for the early warning and supervision of farrowing behaviors based on the embedded artificial-intelligence computing platform (NVIDIA Jetson Nano). This lightweight deep learning method allows the rapid processing of sow farrowing video data at edge nodes, reducing the bandwidth requirement and ensuring data security in the network transmission. Experiments indicated that after the model was migrated to the Jetson Nano, its precision of sow postures and newborn piglets detection was 93.5%, with a recall rate of 92.2%, and the detection speed was increased by a factor larger than 8. The early warning of 18 approaching farrowing (5 h) sows were tested. The mean error of warning was 1.02 h.
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Cruzamento , Animais , Suínos , Humanos , Animais Recém-NascidosRESUMO
The domestic dog has been given considerable attention as a system for investigating the genetics of human diseases. Population diversity and breed structure are unique features that make dogs particularly amenable to genetic studies. Dogs show distinguished features of breed-specific homogeneity, which is associated with striking interbreed heterogeneity. This review discusses the significance of studying the genetic maps, genome-wide association studies (GWAS), and usefulness of this species as an animal model. Most canine genetic disorders are similar to those of humans, including inherited, psychiatric, and genetic disorders. In addition to revealing new candidate genes, canine models allow access to experimental resources, such as cells, tissues, and even live animals, for research and intervention purposes.
Le chien domestique a reçu une attention considérable en tant que système d'investigation de la génétique des maladies humaines. La diversité de la population et la structure de la race sont des caractéristiques uniques qui rendent les chiens particulièrement propices aux études génétiques. Les chiens présentent des caractéristiques distinctes d'homogénéité spécifique à la race, qui est associée à une hétérogénéité interraciale frappante. Cette revue traite de l'importance de l'étude des cartes génétiques, des études d'association à l'échelle du génome (GWAS) et de l'utilité de cette espèce en tant que modèle animal. La plupart des troubles génétiques canins sont similaires à ceux des humains, y compris les troubles héréditaires, psychiatriques et génétiques. En plus de révéler de nouveaux gènes candidats, les modèles canins permettent d'accéder à des ressources expérimentales, telles que des cellules, des tissus et même des animaux vivants, à des fins de recherche et d'intervention.(Traduit par Docteur Serge Messier).
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Doenças do Cão , Estudo de Associação Genômica Ampla , Humanos , Animais , Cães , Estudo de Associação Genômica Ampla/veterinária , Genoma , Genômica , Cruzamento , Doenças do Cão/genéticaRESUMO
Restricted maximum likelihood estimation of genetic parameters accounting for genomic relationships has been reported to impose computational burdens which typically are many times higher than those of corresponding analyses considering pedigree based relationships only. This can be attributed to the dense nature of genomic relationship matrices and their inverses. We outline a reparameterisation of the multivariate linear mixed model to principal components and its effects on the sparsity pattern of the pertaining coefficient matrix in the mixed model equations. Using two data sets we demonstrate that this can dramatically reduce the computing time per iterate of the widely used 'average information' algorithm for restricted maximum likelihood. This is primarily due to the fact that on the principal component scale, the first derivatives of the coefficient matrix with respect to the parameters modelling genetic covariances between traits are independent of the relationship matrix between individuals, i.e. are not afflicted by a multitude of genomic relationships.
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Cruzamento , Modelos Genéticos , Humanos , Funções Verossimilhança , Genômica/métodos , Fenótipo , Algoritmos , LinhagemRESUMO
Arctic-nesting geese face energetic challenges during spring migration, including ecological barriers and weather conditions (e.g., precipitation and temperature), which in long-lived species can lead to a trade-off to defer reproduction in favor of greater survival. We used GPS location and acceleration data collected from 35 greater white-fronted geese of the North American midcontinent and Greenland populations at spring migration stopovers, and novel applications of Bayesian dynamic linear models to test daily effects of minimum temperature and precipitation on energy expenditure (i.e., overall dynamic body acceleration, ODBA) and proportion of time spent feeding (PTF), then examined the daily and additive importance of ODBA and PTF on probability of breeding deferral using stochastic antecedent models. We expected distinct responses in behavior and probability of breeding deferral between and within populations due to differences in stopover area availability. Time-varying coefficients of weather conditions were variable between ODBA and PTF, and often did not show consistent patterns among birds, indicating plasticity in how individuals respond to conditions. An increase in antecedent ODBA was associated with a slightly increased probability of deferral in midcontinent geese but not Greenland geese. Probability of deferral decreased with increased PTF in both populations. We did not detect any differentially important time periods. These results suggest either that movements and behavior throughout spring migration do not explain breeding deferral or that ecological linkages between bird decisions during spring and subsequent breeding deferral were different between populations and across migration but occurred at different time scales than those we examined.
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Migração Animal , Gansos , Humanos , Animais , Gansos/fisiologia , Teorema de Bayes , Migração Animal/fisiologia , Estações do Ano , Temperatura , Cruzamento , ProbabilidadeRESUMO
Identifying the causes and fitness consequences of intraspecific variation in cognitive performance is fundamental to understand how cognition evolves. Selection may act on different cognitive traits separately or jointly as part of the general cognitive performance (GCP) of the individual. To date, few studies have examined simultaneously whether individual cognitive performance covaries across different cognitive tasks, the relative importance of individual and social attributes in determining cognitive variation, and its fitness consequences in the wild. Here, we tested 38 wild southern pied babblers (Turdoides bicolor) on a cognitive test battery targeting associative learning, reversal learning and inhibitory control. We found that a single factor explained 59.5% of the variation in individual cognitive performance across tasks, suggestive of a general cognitive factor. GCP varied by age and sex; declining with age in females but not males. Older females also tended to produce a higher average number of fledglings per year compared to younger females. Analysing over 10 years of breeding data, we found that individuals with lower general cognitive performance produced more fledglings per year. Collectively, our findings support the existence of a trade-off between cognitive performance and reproductive success in a wild bird.
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Animais Selvagens , Passeriformes , Humanos , Animais , Feminino , Cruzamento , Reprodução , CogniçãoRESUMO
The extraordinary genetic and behavioural diversity of dog breeds provides a unique opportunity for investigating the heritability of cognitive traits, such as problem-solving ability, social cognition, inhibitory control, and memory. Previous studies have mainly investigated cognitive differences between breed groups, and information on individual dog breeds is scarce. As a result, findings are often contradictory and inconsistent. The aim of this study was to provide more clarity on between-breed differences of cognitive traits in dogs. We examined the performance of 13 dog breeds (N = 1002 dogs) in a standardized test battery. Significant breed differences were found for understanding of human communicative gestures, following a human's misleading gesture, spatial problem-solving ability in a V-detour task, inhibitory control in a cylinder test, and persistence and human-directed behaviour during an unsolvable task. Breeds also differed significantly in their behaviour towards an unfamiliar person, activity level, and exploration of a novel environment. No significant differences were identified in tasks measuring memory or logical reasoning. Breed differences thus emerged mainly in tasks measuring social cognition, problem-solving, and inhibitory control. Our results suggest that these traits may have come under diversifying artificial selection in different breeds. These results provide a deeper understanding on breed-specific traits in dogs.
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Resolução de Problemas , Cognição Social , Cães , Animais , Humanos , Cruzamento , Comunicação , AtençãoRESUMO
BACKGROUND: Outbreaks of dengue fever caused by viruses transmitted by Aedes aegypti mosquitoes are repeated occurrences in West Africa. In recent years, Burkina Faso has experienced major dengue outbreaks, most notably in 2016 and 2017 when 80% of cases were recorded in Ouagadougou City (Central Health Region). In order to better understand the ecology of this vector and to provide information for use in developing control measures, a study on the characteristics of Aedes container breeding sites and the productivity of such sites, as measured by the abundance of immature stages and resultant adult body size, was undertaken in three health districts (Baskuy, Bogodogo and Nongremassom) of Ouagadougou. METHODS: Adult mosquitoes were collected indoors and outdoors in 643 households during the rainy season from August to October 2018. The presence of water containers was systematically recorded and the containers examined for the presence or absence of larvae. Characteristics of the container breeding sites, including size of the container and temperature, pH and conductivity of the water contained within, were recorded as well as the volume of water. Traditional Stegomyia indices were calculated as quantitative indicators of the risk of dengue outbreaks; generalised mixed models were fitted to larval and pupal densities, and the contribution of each covariate to the model was evaluated by the Z-value and associated P-value. RESULTS: A total of 1061 container breeding sites were inspected, of which 760 contained immature stages of Ae. aegypti ('positive' containers). The most frequent container breeding sites found in each health district were tyres and both medium (buckets/cans/pots) and large (bins/barrels/drums) containers; these containers were also the most productive larval habitats and the types that most frequently tested positive. Of the Stegomyia indices, the Breteau, House and Container indices exceeded WHO dengue risk thresholds. Generalised linear mixed models showed that larval and pupal abundances were associated with container type, physicochemical characteristics of the water and collection month, but there were significant differences among container types and among health districts. Aedes aegypti body size was positively associated with type and diameter of the container, as well as with electrical conductivity of the water, and negatively associated with pH and temperature of the water and with the level of exposure of the container to sunlight. CONCLUSION: This study provides data on putative determinants of the productivity of habitats regarding Ae. aegypti immature stages. These data are useful to better understand Ae. aegypti proliferation. The results suggest that identifying and targeting the most productive container breeding sites could contribute to dengue vector control strategies in Burkina Faso.
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Aedes , Dengue , Animais , Adulto , Humanos , Burkina Faso/epidemiologia , Mosquitos Vetores , Ecossistema , Pupa , Cruzamento , Larva , ÁguaRESUMO
The present study has been designed to devise a pen-side hematological formula for estimation of hemoglobin (Hb) from packed cell volume (PCV) in Cholistani breed of cattle being reared under pastoralism in Cholistan desert, Pakistan. It also aims to validate the soundness of rule of calculating Hb concentration as one-third of PCV and vice versa as being used in human medicine. Cholistani cattle (n = 364) were bled for PCV determination (microhematocrit) method and Hb estimation (hematology analyzer) (HbD) as well as through calculation being one-third of PCV (HbC). The independent-sample t-test was implied for deducing difference between HbD and HbC, and between HbD and corrected Hb (CHb) for all study groups. The CHb was deduced through regression prediction equation attained from linear regression model. Scatter-plots were drawn and linear regression was carried out between various studied hematological attributes. Significantly (P ≤ 0.01) positive correlation coefficient was noticed for all study groups being highest for female adult stock (r = 0.893; adjusted R-square = 0.79) between HbD and PCV and between HbD and HbC. The regression equation for overall results attained, i.e., Hb = 0.13 (PCV) + 6.3 was used to deduce CHb. A non-significant (P ≥ 0.05) difference was noticed between HbD and CHb. In conclusion, a convention of human clinical medicine that Hb concentration is third of PCV and vice versa cannot be implied for Cholistani cattle. A different equation, i.e., Hb (g/dL) = 0.13 (PCV) + 6.3 may provide reliable results for Hb estimation from the PCV in cattle.
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Cruzamento , Hematócrito , Hemoglobinas , Animais , Bovinos , Feminino , Hematócrito/veterinária , Hemoglobinas/análise , PaquistãoRESUMO
The white yak, a type of unique and valuable farm animals on the Qinghai-Tibet Plateau, are mainly distributed in Tianzhu (County of Gansu Province), Menyuan, Huzhu and Ledu (three Counties of Qinghai Province) in China. In the present study, the Y-chromosomal genetic diversity, differentiation and phylogeny of three Chinese white yak breeds/populations (Tianzhu, Huzhu and Menyuan) were comprehensively explored using five Y-SNPs (SRY4, USP9Y, UTY19, AMELY3 and OFD1Y10) and one Y-STR (INRA189) markers. The results showed that six Y-haplotypes (H1Y1, H9Y1, H10Y1, H11Y2, H12Y2 and H13Y2) were identified in 97 male yak from three white yak breeds/populations. Among these haplotypes, H1Y1, H10Y1 and H11Y2 were shared by all of breeds/populations and H12Y2 was shared by Tianzhu and Huzhu populations. However, H9Y1 and H13Y2 haplotypes were only detected in Menyuan and Tianzhu white yak populations, respectively. The Y-haplotype diversity was maximum in Huzhu white yak (0.7500 ± 0.0349), the medium in Tianzhu white yak (0.6881 ± 0.0614) and the lowest in Menyuan white yak (0.5720 ± 0.0657). The total Y-haplotype diversity of three white yak breeds/populations was 0.7567 ± 0.0233, indicating rich paternal genetic diversity in white yak. The FST values showed a moderate differentiation between Tianzhu and Menyuan (FST = 0.0763, P < 0.05) populations, but a weak differentiation between Huzhu and Tianzhu white yak breeds/populations (FST = 0.0186, P > 0.05) and Huzhu and Menyuan (FST = - 0.005, P > 0.05) populations. The clustering analysis revealed a close genetic relationship between Huzhu and Menyuan white yak, both were far from Tianzhu white yak breed. The phylogenetic analyses showed that white yak had two Y-haplogroups/lineages (Y1 and Y2) with two potential paternal origins. The findings of present study provide new insight into the basic information for the formulation of molecular breeding programs of white yak. Moreover, it also contributes to the conservation and utilization of this special animal genetic resource.
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Bovinos , Variação Genética , Filogenia , Polimorfismo de Nucleotídeo Único , Animais , Bovinos/genética , Masculino , China , Haplótipos , CruzamentoRESUMO
BACKGROUND: Recurrent selection is a foundational breeding method for quantitative trait improvement. It typically features rapid breeding cycles that can lead to high rates of genetic gain. Usually, generations are discrete in recurrent selection, which means that breeding candidates are evaluated and considered for selection for only one cycle. Alternately, generations can overlap, with breeding candidates considered for selection as parents for multiple cycles. With recurrent genomic selection but not phenotypic selection, candidates can be re-evaluated by using genomic estimated breeding values without additional phenotyping of the candidates themselves. Therefore, it may be that candidates with true high breeding values discarded in one cycle due to underestimation of breeding value could be identified and selected in subsequent cycles. The consequences of allowing generations to overlap in recurrent selection are unknown. We assessed whether maintaining overlapping and discrete generations led to differences in genetic gain for phenotypic, genomic truncation, and genomic optimum contribution recurrent selection by stochastic simulation. RESULTS: With phenotypic selection, overlapping generations led to decreased genetic gain compared to discrete generations due to increased selection error bias. Selected individuals, which were in the upper tail of the distribution of phenotypic values, tended to also have high absolute error relative to their true breeding value compared to the overall population. Without repeated phenotyping, these individuals erroneously believed to have high value were repeatedly selected across cycles, leading to decreased genetic gain. With genomic truncation selection, overlapping and discrete generations performed similarly as updating breeding values precluded repeatedly selecting individuals with inaccurately high estimates of breeding values in subsequent cycles. Overlapping generations did not outperform discrete generations in the presence of a positive genetic trend with genomic truncation selection, as individuals from previous breeding cycles typically had truly lower breeding values than candidates from the current generation. With genomic optimum contribution selection, overlapping and discrete generations performed similarly, but overlapping generations slightly outperformed discrete generations in the long term if the targeted inbreeding rate was extremely low. CONCLUSION: Maintaining discrete generations in recurrent phenotypic selection leads to increased genetic gain, especially at low heritabilities, by preventing selection error bias. With genomic truncation selection and genomic optimum contribution selection, genetic gain does not differ between discrete and overlapping generations assuming non-genetic effects are not present. Overlapping generations may increase genetic gain in the long term with very low targeted rates of inbreeding in genomic optimum contribution selection.
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Cruzamento , Seleção Genética , Humanos , Endogamia , Genoma , Genômica/métodos , Modelos GenéticosRESUMO
The goal of this study is to use indirect ELISA to determine the concentration of major heat shock proteins (Hsps) in Kankrej (Bos indicus) breeding bulls and their relationship with certain male phenotypic traits including sexual behavior, sperm quality, and bull fertility in different seasons. The seasonal fluctuation in the concentration of three major Hsps (60, 70, and 90) was determined using an indirect enzyme-linked immunosorbent assay (ELISA). According to the findings, Hsps levels are significantly higher during the summer season and are associated with both fresh and post-thawed semen quality traits in Kankrej breeding bulls. The better sexual behavior of bulls and seminal parameters of fresh or thawed semen was observed in the winter season together with the lower concentrations of HSPs. These could suggest negative association between HSPs with bull sexual behavior and seminal parameters. As a result, the concentration of Hsps in breeding bulls may be a useful indicator for determining fertility traits.