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1.
Vet Clin North Am Equine Pract ; 36(2): 211-234, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32534857

RESUMO

Genetic testing in horses began in the 1960s, when parentage testing using blood group markers became the standard. In the 1990s, parentage testing shifted from evaluating blood groups to DNA testing. The development of genetics and genomics in both human and veterinarian medicine, along with continued technological advances in the last 2 decades, has helped unravel the causal variants for many horse traits. Genetic testing is also now possible for a variety of phenotypic and disease traits and is used to assist in breeding and clinical management decisions. This article describes the genetic tests that are currently available for horses.


Assuntos
Testes Genéticos/veterinária , Cavalos/genética , Animais , Cruzamento/métodos , Doenças dos Cavalos/genética
2.
PLoS One ; 15(5): e0233040, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32396551

RESUMO

The aim of this study was to identify breeding practices and trait preferences for indigenous sheep in three districts (Estie, Farta and Lay Gayient) located in the northwest highlands of Ethiopia. Questionnaire survey and choice experiment methods were used to collect data from 370 smallholder farmers. Respondents were selected randomly among smallholder farmers who own sheep in the aforementioned districts. A generalized multinomial logit model was employed to examine preferences for sheep attributes, while descriptive statistics and index values were computed to describe sheep breeding practices. Having the highest index value of 0.36, income generation was ranked as the primary reason for keeping sheep, followed by meat and manure sources. The average flock size per smallholder farmer was 10.21 sheep. The majority of the smallholder farmers (91%) have the experience of selecting breeding rams and ewes within their own flock using diverse criteria. Given the highest index value of 0.34, body size was ranked as a primary ram and ewe selection criteria, followed by coat color. Furthermore, choice modeling results revealed that tail type, body size, coat color, growth rate, horn and ear size have shown significant influences on smallholder farmers' preference for breeding rams (P<0.01). The part-worth utility coefficients were positive for all ram attributes except ear size. For breeding ewes, mothering ability, coat color, body size, lambing interval, growth rate, tail type and litter size have shown significant effects on choice preferences of smallholder farmers (P<0.05). Moreover, significant scale heterogeneity was observed among respondents for ewe attributes (P<0.001). Overall, the results implied that sheep breeding objectives suitable for the northwest highlands of the country can be derived from traits such as linear body measurement, weight and survival at different ages, and lambing intervals. However, selection decisions at the smallholder level should not only be based on estimated breeding values of traits included in the breeding objective but instead, incorporate ways to address farmers' preference for qualitative traits.


Assuntos
Cruzamento/métodos , Carneiro Doméstico , Abate de Animais , Criação de Animais Domésticos/métodos , Animais , Etiópia , Fazendeiros , Feminino , Hibridização Genética , Masculino , Seleção Artificial , Carneiro Doméstico/anatomia & histologia , Carneiro Doméstico/crescimento & desenvolvimento , Inquéritos e Questionários
3.
PLoS One ; 15(4): e0232144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32330204

RESUMO

The black soldier fly Hermetia illucens is gaining growing interest as a tool for the valorisation of bio-waste in a circular economy perspective. Although a wide variety of studies are available for larvae rearing, the indoor breeding of adults still presents a great challenge for industrial purposes. This study was designed to assess the simultaneous influence of 3 different light sources (the Mix of LED UV:blue:green 1:1:3, White LED, Neon light) and 3 types of nutrition (sugar and water, only water, no sugar no water) on adult performances, obtaining different egg production parameters that included the number and weight of the egg masses and single eggs laid by the females, the duration of pre-oviposition and oviposition period, the adult life span, the hatchability of the eggs. Our results showed that production parameters are influenced mainly by nutrition rather than light factor, although light plays an important secondary role. Moreover, the presence of sugar positively affects the egg production (12,93-27,10 mg eggs/female) and increases oviposition period (18,2-31,8 days) and adult lifespan (20,79-27,11 days). Light sources also affect egg production parameters, with the exposure to the Mix of LEDs resulting in the best performance of flies. Results obtained from this study are very useful for the design and management of an efficient industrial black soldier fly mass rearing process.


Assuntos
Larva/fisiologia , Oviposição/fisiologia , Simuliidae/anatomia & histologia , Simuliidae/fisiologia , Animais , Cruzamento/métodos , Feminino , Luz , Longevidade/fisiologia , Parto/fisiologia , Gravidez
4.
PLoS One ; 15(4): e0231131, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32282838

RESUMO

In reproductive hens, a feed restriction is an usual practice to improve metabolic and reproductive disorders. However, it acts a stressor on the animal. In mammals, grape seed extracts (GSE) reduces oxidative stress. However, their effect on endocrine and tissue response need to be deepened in reproductive hens. Here, we evaluated the effects of time and level of GSE dietary supplementation on growth performance, viability, oxidative stress and metabolic parameters in plasma and metabolic tissues in reproductive hens and their offsprings. We designed an in vivo trial using 4 groups of feed restricted hens: A (control), B and C (supplemented with 0.5% and 1% of the total diet composition in GSE since week 4, respectively) and D (supplemented with 1% of GSE since the hatch). In hens from hatch to week 40, GSE supplementation did not affect food intake and fattening whatever the time and dose of supplementation. Body weight was significantly reduced in D group as compared to control. In all hen groups, GSE supplementation decreased plasma oxidative stress index associated to a decrease in the mRNA expression of the NOX4 and 5 oxidant genes in liver and muscle and an increase in SOD mRNA expression. This was also associated to decreased plasma chemerin and increased plasma adiponectin and visfatin levels. Interestingly, maternal GSE supplementation increased the live body weight and viability of chicks at hatching and 10 days of age. This was associated to a decrease in plasma and liver oxidative stress parameters. Taken together, GSE maternal dietary supplementation reduces plasma and tissue oxidative stress associated to modulation of adipokines without affecting fattening in reproductive hens. A 1% GSE maternal dietary supplementation increased offspring viability and reduced oxidative stress suggesting a beneficial transgenerational effect and a potential use to improve the quality of the progeny in reproductive hens.


Assuntos
Criação de Animais Domésticos/métodos , Antioxidantes/administração & dosagem , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Extrato de Sementes de Uva/administração & dosagem , Adiponectina/sangue , Adiponectina/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Cruzamento/métodos , Quimiocinas/sangue , Quimiocinas/metabolismo , Galinhas/sangue , Dieta/efeitos adversos , Dieta/veterinária , Feminino , Troca Materno-Fetal/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Gravidez , Reprodução/fisiologia
5.
PLoS One ; 15(4): e0231008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240258

RESUMO

Cassava green mite [CGM, Mononychellus tanajoa (Bondar)] is the most destructive dry-season pest in most cassava production areas. The pest is responsible for cassava fresh root yield losses of over 80%. Deployment of CGM resistant cultivars is the most cost-effective and sustainable approach of alleviating such production losses. The purposes of this study were to validate the stability of CGM resistance genes found in previously published results, to identify new genes for CGM resistance in bi-parental mapping population and estimate the heritability of the trait. A total of 109 F1 progeny derived from a cross between CGM resistant parent, TMEB778 and a very susceptible parent, TMEB419 were evaluated under CGM hotspot areas in Nigeria for two cropping seasons. A total of 42,204 SNP markers with MAF ≥ 0.05 were used for single-marker analysis. The most significant QTL (S12_7962234) was identified on the left arm on chromosome 12 which explained high phenotypic variance and harboured significant single nucleotide polymorphism (SNP) markers conferring resistance to CGM and leaf pubescence (LP). Colocalization of the most significant SNP associated with resistance to CGM and LP on chromosome 12 is possibly an indication of a beneficial pleiotropic effect or are physically linked. These significant SNPs markers were intersected with the gene annotations and 33 unique genes were identified within SNPs at 4 - 8MB on chromosome 12. Among these genes, nine novel candidate genes namely; Manes.12077600, Manes.12G086200, Manes.12G061200, Manes.12G083100, Manes.12G082000, Manes.12G094100, Manes.12G075600, Manes.12G091400 and Manes.12G069300 highly expressed direct link to cassava green mite resistance. Pyramiding the new QTL/genes identified on chromosome 12 in this study with previously discovered loci, such on chromosome 8, will facilitate breeding varieties that are highly resistant CGM.


Assuntos
Resistência à Doença/genética , Manihot/genética , Ácaros/patogenicidade , Doenças das Plantas/genética , Locos de Características Quantitativas/genética , Animais , Cruzamento/métodos , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Ligação Genética/genética , Marcadores Genéticos/genética , Masculino , Manihot/parasitologia , Nigéria , Fenótipo , Doenças das Plantas/parasitologia , Polimorfismo de Nucleotídeo Único/genética
6.
PLoS One ; 15(3): e0230239, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187226

RESUMO

The ex situ population of fishing cats (Prionailurus viverrinus) has become increasingly important for the conservation of this species. Unfortunately, captivity-induced stress is a concern and potential factor for lack of breeding success in this small felid, resulting in an unsustainable population. The objectives of this study were to: 1) validate an enzyme immunoassay for monitoring of fecal glucocorticoid metabolite (FGM) concentrations in the fishing cat; 2) identify potential exogenous stressors in the captive environment; 3) pinpoint management techniques that may lower FGM concentrations; and 4) determine if FGM concentrations are related to breeding success. Through a successful adrenocorticotrophic hormone challenge and additional laboratory methods, a cortisol enzyme immunoassay was validated as an effective tool for detecting FGM in this species. Between 2010 and 2013, longitudinal FGM monitoring was conducted in 26 fishing cats in the North American Species Survival Plan®. Exogenous stressors that elevated FGM concentrations included: chemical immobilizations; permanent transfers between facilities; construction; facility events; and fights/aggression among breeding pairs. Management factors that lowered FGM concentrations included: increased animal-keeper interaction through formal training; and providing indoor, off-exhibit, holding areas. In addition, social housing of individuals (either established breeding pairs or same sex pairs) decreased FGM concentrations. Individuals with breeding success (defined as observed copulations during the study period) also had lower FGM concentrations than unsuccessful individuals. Findings indicate that management factors play a role in lowering glucocorticoid (stress) levels in fishing cats, which may ultimately affect breeding success in the ex situ population.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Animais de Zoológico/metabolismo , Animais , Cruzamento/métodos , Gatos , Fezes , Feminino , Glucocorticoides/metabolismo , Hidrocortisona/metabolismo , Masculino , Reprodução/fisiologia
8.
Electron. j. biotechnol ; 44: 25-32, Mar. 2020. graf, tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1087637

RESUMO

BACKGROUND: Cultivated peanut (Arachis hypogaea. L) represents one of the most important oil crops in the world. Although much effort has been expended to characterize microsatellites or Simple Sequence Repeats (SSRs) in peanut, the quantity and quality of the markers in breeding applications remain limited. Here, genome-wide SSR characterization and marker development were performed using the recently assembled genome of the cultivar Tifrunner. RESULTS: In total, 512,900 microsatellites were identified from 2556.9-Mb genomic sequences. Based on the flanking sequences of the identified microsatellites, 7757 primer pairs (markers) were designed, and further evaluated in the assembled genomic sequences of the tetraploid Arachis cultivars, Tifrunner and Shitouqi, and the diploid ancestral species, A. duranensis and A. ipaensis. In silico PCR analysis showed that the SSR markers had high amplification efficiency and polymorphism in four Arachis genotypes. Notably, nearly 60% of these markers were single-locus SSRs in tetraploid Arachis species, indicating they are more specific in distinguishing the alleles of the A and B sub-genomes of peanut. In addition, two markers closely related with purple testa color and 27 markers near to FAD2 genes were identified, which could be used for breeding varieties with purple testa and high-oleic acid content, respectively. Moreover, the potential application of these SSR markers in tracking introgressions from Arachis wild relatives was discussed. CONCLUSIONS: This study reported the development of genomic SSRs from assembled genomic sequences of the tetraploid Arachis Tifrunner, which will be useful for diversity analysis, genetic mapping and functional genomics studies in peanut


Assuntos
Arachis/genética , Cruzamento/métodos , Repetições de Microssatélites , Polimorfismo Genético , Marcadores Genéticos , Reação em Cadeia da Polimerase , Genoma , Produtos Agrícolas
9.
PLoS One ; 15(2): e0228964, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049997

RESUMO

Jiaji Duck (JJ) is a Muscovy duck species that possesses many superior characteristics, and it has become an important genetic resource in China. However, to date, its genetic characteristics and genetic relationship with other duck breeds have not been explored yet, which greatly limits the utilization of JJ. In the present study, we investigated the genome sequences of 15 individual ducks representing five different duck populations, including JJ, French Muscovy duck (FF), mallard (YD), hong duck (HD) and Beijing duck (BD). Moreover, we investigated the characteristics of JJ-specific single nucleotide polymorphisms (SNPs) and compared the genome sequences of JJ vs. YD and JJ vs. BD using integrated strategies, including mutation detection, selective screening, and Gene Ontology (GO) analysis. More than 40 Gb of clean data were obtained for each population (mean coverage of 13.46 Gb per individual). A total number of 22,481,367 SNPs and 4,156,829 small insertion-deletions (Indels) were identified for the five duck populations, which could be used as molecular markers in breeding and utilization of JJ. Moreover, we identified 1,447,932 JJ-specific SNPs, and found that genes covering at least one JJ-specific SNP mainly involved in protein phosphorylation and dephosphorylation, as well as DNA modification. Phylogenetic tree and principal components analysis (PCA) revealed that the genetic relationship of JJ was closest to FF, while it was farthest to BD. A total of 120 and 111 genes were identified as positive selection genes for JJ vs. BD and JJ vs. YD, respectively. GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the positive selection genes for JJ vs. BD ducks mainly involved in pigmentation, muscle contraction and stretch, gland secretion, and immunology, while the positive selection genes obtained from JJ vs. YD ducks mainly involved in embryo development, muscle contraction and stretch, and gland secretion. Taken together, our findings enabled us to better understand the characteristics of JJ and provided a molecular basis for the breeding and hybrid utilization of JJ in the future.


Assuntos
Patos/genética , Genoma/genética , Animais , Cruzamento/métodos , China , Mapeamento Cromossômico/métodos , Feminino , Ontologia Genética , Mutação/genética , Fosforilação/genética , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal/métodos , Sequenciamento Completo do Genoma/métodos
10.
Mol Genet Genomics ; 295(1): 143-154, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31559504

RESUMO

KEY MESSAGE: Floret and seed traits are moderately correlated phenotypically in modern sunflower cultivars, but the underlying genetics are mostly independent. Seed traits in particular are governed in part by epistatic effects among quantitative trait loci. Seed size is an important quality component in marketing commercial sunflower (Helianthus annuus L.), particularly for the in-shell confectionery market, where long and broad seed types are preferred as a directly consumed snack food globally. Floret size is also important because corolla tube length was previously shown to be inversely correlated with pollinator visitation, impacting bee foraging potential and pollinator services to the plant. Commercial sunflower production benefits from pollinator visits, despite being self-compatible, and bees are required in hybrid seed production, where "female" and "male" inbred lines are crossed at field scale. Issues with pollination of long-seed confectionery sunflower suggest that there may be an unfavorable correlation between seed and floret traits; thus, our objective was to determine the strength of the correlation between seed and floret traits, and confirm any co-localization of seed and floret trait loci using genome-wide association analysis in the SAM diversity panel of sunflower. Our results indicate that phenotypic correlations between seed and floret traits are generally low to moderate, regardless of market class, a component of population substructure. Association mapping results mirror the correlations: while a few loci overlap, many loci for the two traits are not overlapping or even adjacent. The genetics of these traits, while modestly quantitative and influenced by epistatic effects, are not a barrier to simultaneous improvement of seed length and pollinator-friendly floret traits. We conclude that breeding for large seed size, which is required for the confectionery seed market, is possible without producing florets too long for efficient use by pollinators, which promotes bee foraging and associated pollination services.


Assuntos
Helianthus/genética , Locos de Características Quantitativas/genética , Sementes/genética , Animais , Abelhas , Cruzamento/métodos , Estudo de Associação Genômica Ampla/métodos , Fenótipo , Polinização/genética
11.
Mol Genet Genomics ; 295(1): 155-176, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31620883

RESUMO

To provision the world sustainably, modern society must increase overall crop production, while conserving and preserving natural resources. Producing more with diminishing water resources is an especially daunting endeavor. Toward the goal of genetically improving drought resilience of cultivated Upland cotton (Gossypium hirsutum L.), this study addresses the genetics of differential yield components referred to as productivity and fiber quality traits under regular-water versus low-water (LW) field conditions. We used ten traits to assess water stress deficit, which included six productivity and four fiber quality traits on two recombinant inbred line (RIL) populations from reciprocally crossed cultivars, Phytogen 72 and Stoneville 474. To facilitate genetic inferences, we genotyped RILs with the CottonSNP63K array, assembled high-density linkage maps of over 7000 SNPs and then analyzed quantitative trait variations. Analysis of variance revealed significant differences for all traits (p < 0.05) in these RIL populations. Although the LW irrigation regime significantly reduced all traits, except lint percent, the RILs exhibited a broad phenotypic spectrum of heritable differences across the water regimes. Transgressive segregation occurred among the RILs, suggesting the possibility of genetic gain through phenotypic selection for drought resilience and perhaps through marker-based selection. Analyses revealed more than 150 quantitative trait loci (QTLs) associated with productivity and fiber quality traits (p < 0.005) on different genomic regions of the cotton genome. The multiple-QTL models analysis with LOD > 3.0 detected 21 QTLs associated with productivity and 22 QTLs associated with fiber quality. For fiber traits, strong clustering and QTL associations occurred in c08 and its homolog c24 as well as c10, c14, and c21. Using contemporary genome sequence assemblies and bioinformatically related information, the identification of genomic regions associated with responses to plant stress/drought elevates the possibility of using marker-assisted and omics-based selection to enhance breeding for drought resilient cultivars and identifying candidate genes and networks. RILs with different responses to drought indicated that it is possible to maintain high fiber quality under LW conditions or reduce the of LW impact on quality. The heritable variation among elite bi-parental RILs for productivity and quality under field drought conditions, and their association of QTLs, and thus specific genomic regions, indicate opportunities for breeding-based gains in water resource conservation, i.e., enhancing cotton's agricultural sustainability.


Assuntos
Genoma de Planta/genética , Gossypium/genética , Cruzamento/métodos , Mapeamento Cromossômico/métodos , Fibra de Algodão , Secas , Ligação Genética/genética , Genótipo , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
12.
Trop Anim Health Prod ; 52(1): 71-78, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31325019

RESUMO

This study describes the results of a farm-based welfare assessment, herd management, and some yield indicators in Northern Cyprus dairy goat farms. Out of 324 intensive milk goat farms which produce goats, only the 42 goat farms which had 7950 heads were chosen by random sampling in Northern Cyprus (2016), and face-to-face questionnaires and observations were conducted to collect data. Regarding the breeding techniques in these farms, of all the goats in these farms, 45.2% were cross-breed, 38.1% were Damascus, 11.9% were Saanen, and 4.8% were hair goats. The average of the total number of animals was 211.38 ± 209 heads. The average number of pens and the number of animals per pen in the farms, which had 2 to 5 pens, were 67 ± 49.5 heads. The barn types of these farms were observed to be semi-open and nearly open (95%). 45.5% of the farms made a single milking in a day. The most significant reason for this was that the suckling of the kids lasted 3 months or more in 73.8% of the farms. Natural random mating was applied to 69% of the farms. The 45.2% of the farms applied additional feeding before the mating season. The rate of multiple births was 24.76%. The mortality rate in kids was greater than 10% in the 57% of farms examined. The 75% of kids had diarrhea, 33% had umbilicus infections, and 33% suffered from respiratory problems. Among the adult goats of the surveyed farms, the most important problem was external parasites (100%). The second and third problems were overgrown claws (80.9%) and common abscesses (80.95%). Regarding the biosecurity indicators, the general disinfection percentage of farms was 78.57%. However, veterinarian controls were conducted only in the 26.9% of the farms on a regular basis. In these farms, there was no significant difference between the breeds regarding their breeding and reproduction techniques or health indicators. The entrance of the farms carries a high risk for biosecurity. Heat stress is quite important factor for the milk quality.


Assuntos
Cruzamento , Cabras , Indicadores Básicos de Saúde , Animais , Cruzamento/métodos , Chipre , Indústria de Laticínios/métodos , Fazendas , Feminino , Cabras/crescimento & desenvolvimento , Cabras/parasitologia , Cabras/fisiologia , Transtornos de Estresse por Calor , Leite , Mortalidade , Administração da Prática da Medicina Veterinária , Reprodução , Estações do Ano
13.
Mol Genet Genomics ; 295(1): 67-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31473809

RESUMO

The use of genomic selection (GS) has stimulated a new way to utilize molecular markers in breeding for complex traits in the absence of phenotypic data. GS can potentially decrease breeding cycle by selecting the progeny in the early stages. The objective of this study was to experimentally evaluate the potential value of genomic selection in Upland cotton breeding. Six fiber quality traits were obtained in 3 years of replicated field trials in Starkville, MS. Genotyping-by-sequencing-based genotyping was performed using 550 recombinant inbred lines of the multi-parent advanced generation inter-cross population, and 6292 molecular markers were used for the GS analysis. Several methods were compared including genomic BLUP (GBLUP), ridge regression BLUP (rrBLUP), BayesB, Bayesian LASSO, and reproducing kernel hilbert spaces (RKHS). The average heritability (h2) ranged from 0.38 to 0.88 for all tested traits across the 3 years evaluated. BayesB predicted the highest accuracies among the five GS methods tested. The prediction ability (PA) and prediction accuracy (PACC) varied widely across 3 years for all tested traits and the highest PA and PACC were 0.65, and 0.69, respectively, in 2010 for fiber elongation. Marker density and training population size appeared to be very important factors for PA and PACC in GS. Results indicated that BayesB-based GS method could predict genomic estimated breeding value efficiently in Upland cotton fiber quality attributes and has great potential utility in breeding by reducing cost and time.


Assuntos
Genoma de Planta/genética , Gossypium/genética , Locos de Características Quantitativas/genética , Seleção Genética/genética , Teorema de Bayes , Cruzamento/métodos , Fibra de Algodão , Marcadores Genéticos/genética , Genômica/métodos , Modelos Genéticos , Fenótipo
14.
Am J Primatol ; 82(1): e23085, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31875991

RESUMO

Rhesus monkeys are typically seasonal breeders but can be induced to extend the timing of their mating and births under captive conditions. The following analyses evaluated the potential impact of extending their pregnancies and deliveries year-round. Birth records from a large breeding colony housed in an indoor facility with a constant 14-hr light/10-hr dark cycle were analyzed across 25 years to examine seasonal trends in monkeys that mated in one of two ways: spontaneous in social groups or with a scheduled, timed-mating protocol. The dates of delivery and birth weights for 2,084 infants were used in these analyses. Younger nulliparous females mating in social groups evinced a clear seasonal peak when birthing their first infant. However, older females, both primiparous and multiparous, could be bred continuously, which enable the birth of infants in every month of the year. Based on the live birth rate, infant birth weights, high survival rates, and the normal sex ratio of infants birthed year-round, there were no adverse effects of breeding rhesus monkeys in this way. The continuous availability of infant births can be very advantageous for many types of research programs.


Assuntos
Cruzamento/métodos , Macaca mulatta/fisiologia , Gravidez/fisiologia , Criação de Animais Domésticos/métodos , Animais , Coeficiente de Natalidade , Peso ao Nascer , Feminino , Masculino , Estações do Ano , Razão de Masculinidade
15.
Theriogenology ; 142: 315-319, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31711693

RESUMO

The aim of this study was to evaluate the effect of body weight, oxytocin deposition in the uterus at artificial insemination (AI), vaginal cytology, serum progesterone (P4) concentration at AI, semen volume and total sperm cells per AI on whelping rate and litter size of English Bulldogs bitches following intrauterine surgical semen deposition. Seventy-eight English Bulldog bitches were artificially inseminated via semen infusion (number of sperm cells inseminated 300-2500 × 106) at the uterine body with fresh semen without extender and under general anesthesia. Whelping rate was greater (P < 0.05) in bitches with >23 kg than bitches with <23 kg (83.9 vs 63.8%). Whelping rate was greater (P < 0.01) in bitches with >75% vaginal cornified epithelium at AI (85.1%) than animals with <75% cornified epithelium (51.6%). Whelping rates were influenced (P < 0.01) by the semen volume at AI (54.3% vs 86.1% for bitches receiving <4 mL or >4 mL of semen). Litter size was larger (P < 0.05) in bitches >23 kg than lighter animals (3.72 ±â€¯1.79 and 2.30 ±â€¯1.46 pups per litter, respectively). Litter size was not influenced by sperm concentration, semen volume, vaginal cytology, serum P4 concentration and infusion of oxytocin in the uterus at AI (P > 0.1). The results of this study indicate that increasing body weight of English Bulldog bitches is related to higher whelping rates and larger litter size. Also, >75% of superficial cornified vaginal cells (squamous) at AI and >4 mL semen volume maximize whelping rates in this breed of dogs.


Assuntos
Cruzamento , Cães , Infertilidade/etiologia , Inseminação Artificial , Animais , Líquidos Corporais , Peso Corporal/fisiologia , Cruzamento/métodos , Feminino , Fertilidade/fisiologia , Infertilidade/veterinária , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Tamanho da Ninhada de Vivíparos , Masculino , Ocitocina/análise , Gravidez , Fatores de Risco , Sêmen/citologia , Sêmen/fisiologia , Resultado do Tratamento , Vagina/química , Vagina/citologia , Vagina/cirurgia
17.
Genet Sel Evol ; 51(1): 73, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823719

RESUMO

BACKGROUND: Hamiltonian Monte Carlo is one of the algorithms of the Markov chain Monte Carlo method that uses Hamiltonian dynamics to propose samples that follow a target distribution. The method can avoid the random walk behavior to achieve a more effective and consistent exploration of the probability space and sensitivity to correlated parameters, which are shortcomings that plague many Markov chain Monte Carlo methods. However, the performance of Hamiltonian Monte Carlo is highly sensitive to two hyperparameters. The No-U-Turn Sampler, an extension of Hamiltonian Monte Carlo, was recently introduced to automate the tuning of these hyperparameters. Thus, this study compared the performances of Gibbs sampling, Hamiltonian Monte Carlo, and the No-U-Turn Sampler for estimating genetic parameters and breeding values as well as sampling qualities in both simulated and real pig data. For all datasets, we used a pedigree-based univariate linear mixed model. RESULTS: For all datasets, the No-U-Turn Sampler and Gibbs sampling performed comparably regarding the estimation of heritabilities and accuracies of breeding values. Compared with Gibbs sampling, the estimates of effective sample sizes for simulated and pig data with the No-U-Turn Sampler were 3.2 to 22.6 and 3.5 to 5.9 times larger, respectively. Autocorrelations decreased more quickly with the No-U-Turn Sampler than with Gibbs sampling. When true heritability was low in the simulated data, the skewness of the marginal posterior distributions with the No-U-Turn Sampler was smaller than that with Gibbs sampling. The performance of Hamiltonian Monte Carlo for sampling quality was inferior to that of No-U-Turn Sampler in the simulated data. Moreover, Hamiltonian Monte Carlo could not estimate genetic parameters because of difficulties with the hyperparameter settings with pig data. CONCLUSIONS: The No-U-Turn Sampler is a promising sampling method for animal breeding because of its good sampling qualities: large effective sample sizes, low autocorrelations, and low skewness of marginal posterior distributions, particularly when heritability is low. Meanwhile, Hamiltonian Monte Carlo failed to converge with a simple univariate model for pig data. Thus, it might be difficult to use Hamiltonian Monte Carlo for usual complex models in animal breeding.


Assuntos
Cruzamento/métodos , Suínos/genética , Algoritmos , Animais , Cadeias de Markov , Modelos Estatísticos , Método de Monte Carlo , Suínos/crescimento & desenvolvimento
18.
PLoS One ; 14(12): e0226179, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31830089

RESUMO

Goats play an important role in the livestock sector in Greece. The national herd consists mainly of two indigenous breeds, the Eghoria and Skopelos. Here, we report the population structure and genomic profiles of these two native goat breeds using Illumina's Goat SNP50 BeadChip. Moreover, we present a panel of candidate markers acquired using different genetic models for breed discrimination. Quality control on the initial dataset resulted in 48,841 SNPs kept for downstream analysis. Principal component and admixture analyses were applied to assess population structure. The rate of inbreeding within breed was evaluated based on the distribution of runs of homozygosity in the genome and respective coefficients, the genomic relationship matrix, the patterns of linkage disequilibrium, and the historic effective population size. Results showed that both breeds exhibit high levels of genetic diversity. Level of inbreeding between the two breeds estimated by the Wright's fixation index FST was low (Fst = 0.04362), indicating the existence of a weak genetic differentiation between them. In addition, grouping of farms according to their geographical locations was observed. This study presents for the first time a genome-based analysis on the genetic structure of the two indigenous Greek goat breeds and identifies markers that can be potentially exploited in future selective breeding programs for traceability purposes, targeted genetic improvement schemes and conservation strategies.


Assuntos
Cruzamento/métodos , Genética Populacional , Estudo de Associação Genômica Ampla , Cabras/genética , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Animais , Feminino , Genoma , Genômica , Densidade Demográfica
19.
PLoS One ; 14(12): e0225658, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31794562

RESUMO

To address the need for sensitive high-throughput assays to analyse avian innate and adaptive immune responses, we developed and validated a highly multiplexed qPCR 96.96 Fluidigm Dynamic Array to analyse the transcription of chicken immune-related genes. This microfluidic system permits the simultaneous analysis of expression of 96 transcripts in 96 samples in 6 nanolitre reactions and the 9,216 reactions are ready for interpretation immediately. A panel of 89 genes was selected from an RNA-seq analysis of the transcriptional response of chicken macrophages, dendritic cells and heterophils to agonists of innate immunity and from published transcriptome data. Assays were confirmed to be highly specific by amplicon sequencing and melting curve analysis and the reverse transcription and preamplification steps were optimised. The array was applied to RNA of various tissues from a commercial line of broiler chickens housed at two different levels of biosecurity. Gut-associated lymphoid tissues, bursa, spleen and peripheral blood leukocytes were isolated and transcript levels for immune-related genes were defined. The results identified blood cells as a potentially reliable indicator of immune responses among all the tissues tested with the highest number of genes significantly differentially transcribed between birds housed under varying biosecurity levels. Conventional qPCR analysis of three differentially transcribed genes confirmed the results from the multiplex qPCR array. A highly multiplexed qPCR-based platform for evaluation of chicken immune responses has been optimised and validated using samples from commercial chickens. Apart from applications in selective breeding programmes, the array could be used to analyse the complex interplay between the avian immune system and pathogens by including pathogen-specific probes, to screen vaccine responses, and as a predictive tool for immune robustness.


Assuntos
Galinhas/imunologia , Ensaios de Triagem em Larga Escala/métodos , Interações Hospedeiro-Patógeno/imunologia , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Cruzamento/métodos , Galinhas/genética , Interações Hospedeiro-Patógeno/genética , Imunidade Humoral/genética , Imunidade Inata/genética , Leucócitos/imunologia , Técnicas Analíticas Microfluídicas/métodos , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , RNA-Seq , Vacinas/administração & dosagem , Vacinas/imunologia
20.
Genes (Basel) ; 10(12)2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783652

RESUMO

The equestrian sport horse Swedish Warmblood (SWB) originates from versatile cavalry horses. Most modern SWB breeders have specialized their breeding either towards show jumping or dressage disciplines. The aim of this study was to explore the genomic structure of SWB horses to evaluate the presence of genomic subpopulations, and to search for signatures of selection in subgroups of SWB with high or low breeding values (EBVs) for show jumping. We analyzed high density genotype information from 380 SWB horses born in the period 2010-2011, and used Principal Coordinates Analysis and Discriminant Analysis of Principal Components to detect population stratification. Fixation index and Cross Population Extended Haplotype Homozygosity scores were used to scan the genome for potential signatures of selection. In accordance with current breeding practice, this study highlights the development of two separate breed subpopulations with putative signatures of selection in eleven chromosomes. These regions involve genes with known function in, e.g., mentality, endogenous reward system, development of connective tissues and muscles, motor control, body growth and development. This study shows genetic divergence, due to specialization towards different disciplines in SWB horses. This latter evidence can be of interest for SWB and other horse studbooks encountering specialized breeding.


Assuntos
Cruzamento/métodos , Cavalos/crescimento & desenvolvimento , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Polimorfismo de Nucleotídeo Único , Animais , Feminino , Cavalos/genética , Desequilíbrio de Ligação , Masculino , Análise de Componente Principal , Locos de Características Quantitativas , Seleção Genética , Esportes , Suécia
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