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At least 19 recordsLinked to original sources
PubMed1977

Behavioural and hormonal responses of male rhesus monkeys introduced to females in the breeding and non-breeding seasons.

Six adult male rhesus monkeys were introduced individually to an all-female group for 10 days during the mating season. The initial aggressive responses of the females were rapidly replaced by positive social behaviour, and each male achieved alpha status and had access to social and sexual partners. A repetition of this paradigm in the non-breeding season produced significantly more female aggression, and no male attained high rank or engaged in sexual or other social behaviour. Male testosterone levels rose following introduction to the females in both seasons, but were significantly higher during the breeding season. Hormonal levels following removal from the females suggest a complex interplay between social, sexual and seasonal variables and recent social experiences. The differences in female social behaviour with newly introduced males, as a function of season, suggest an explanation for the seasonal limitation of male troop transfers.

Aggression↗
PubMedDate not supplied

Testicular capillary blood flow in the impubertal lamb and the ram during the breeding and non-breeding seasons.

The testicular capillary blood flow was measured by the 133Xenon clearance technique in the Ile-de-France lambs and rams in Spring and Autumn. Anaesthetized animals were maintained in the supine position and 133Xe was injected into the testicle through the scrotal skin. In the adult, the blood-flow (ml/min./100 g) depended upon the season: 8.3 +/- 1.0 vs 12.7 +/- 0.7 in May and October (P less than 0.001). In the impubertal lamb (50 days old) regardless of the period of the year, the blood flow was the same as in the adult in the breeding season (11.4 +/- 1.2 vs 12.7 +/- 0.7). In prepubertal lambs (120 days old) the rapid increase in testicular weight was not correlated with an increase in the blood flow (9.4 +/- 0.7).

Animals↗
PubMed1976

[Changes in the blood picture during puerperium of Czech white-breed sows under large-scale breeding conditions].

A dynamics of the changes of the red and while blood cell count during puerperium (1st-27th day post partum) was studied in 293 sows of the Czech White breed kept in typical large-scale production conditions. An average count of erythrocytes amounted to 5 513 000 +/- 385 514. In the course of puerperium their count slightly decreased in comparison with the value obtained on the first day p. p. (on the 10th day p. p. the decrease was even highly statistically significant - P less than 0.01). An average amount of hemoglobin was 12.48 +/- 1.22 g per 100 ml of blood; in the course of the nearly whole of puerperium it was slightly higher than on the first day p. p. (in the third week on the threshold of the statistical significance up to the statistical significance - P less than 0.10-0.05-0.01). The value of hematocrit did not fluctuate (average = 38.65 +/- 3.89%), sedimentation slowed down, especially from the end of the second week p. p. The protein of the blood plasma amounted, on an average, to 7.71 +/- 0.84 g per 100 ml; the protein content raised during puerperium in comparison to the 1st day .p. An average count of leukocytes during puerperium was in comparison to the 1st day p.p. An average count of leukocytes during puerperium 12 755 +/- 1529, and it slightly increased in relation to the 1st day p. p. The percentage of neutrophile granulocytes and lymphocytes did not change very much; it reached 46%: 45%. The character of the sow blood during puerperium fluctuated all the time between neutrophile and lymphocytic type with a slight tendency to the prevalence of neutrophile granulocytes. Nevertheless, the proportion of neutrophile granulocytes with rodlike nuclei decreased, and on the other hand, the proportion of neutrophile granulocytes with segmented nuclei increased (a nucleus shift to the right). Original values and ratio of the first day p. p. (T = 6.91%: Seg = 41.13%) changed in the average value of T = 1.93%: Seg = 43.96% during the whole puerperium.

Animal Husbandry↗
PubMed1977

[Microbiological pollution of the environment due to breeding. I. Enterobacteriaceae due to cattle breeding].

Enterobacteriaceae from faeces of cattle belonging to four cattle farms situated in the Ferrara district were investigated. At the same time, investigation was made of effluent sewage and recipient wells (upstream and downstream). The cattle (of the Italian Frisona breed) resulted uncontaminated by Salmonellae, but proved to be very susceptible to Arizona, Citrobacter, Shigella and S. gallinarum-pullorum infections, coming from the environment. Predominant species in faeces were as follows: Proteus, Klebsiella, Enterbacter and coliforms. One farm proved to be heavily polluted by Edwardsiella tarda. Yersinia enterocolitica strains were also isolated from faeces and sewage.

Air Microbiology↗
PubMed1975

A study of the morphology of stallion semen during the breeding and non-breeding seasons.

Season was shown to markedly influence semen characteristics of stallions in Holland, including ejaculate volume, sperm motility, total number of spermatozoa/ejaculate and the percentage of spermatozoa showing morphological abnormalities. Maintenance of normal stallions in continuous light during the winter months and administration of a vitamin and mineral supplement to sub-fertile stallions before the start of the breeding season appeared to improve spermatogenesis significantly.

Animals↗
PubMed2026

A genome-wide assessment of the population structure of thirteen admixed and pure Australian beef cattle breeds.

Knowledge of population structure is a key factor for successful multi-breed genomic prediction, especially in single-step analysis when metafounders are considered. In Australia, current assessments mostly focus on single breeds using a single-step genomic prediction method. However, the effective integration of pedigree, phenotypic, and genomic data in a multi-breed framework still requires further research, especially for combined analyses including admixed and multi-breed populations. This study began with 602,952 genotyped individuals with 8K SNPs in common from 13 beef cattle breeds (Alexandria, Angus, Brahman, Brangus, Charolais, Droughtmaster, Hereford, Kynuna, Limousin, Santa Gertrudis, Shorthorn, Speckle Park, and Wagyu). Due to different numbers of animals being genotyped in each breed, a representative subset of animals was chosen by employing a validated sampling strategy using Gaussian Mixture Models (GMM) complemented by Principal Component Analysis (PCA) within each breed. Subsequently, a specific number of animals in each cluster were randomly selected to capture the entire genetic diversity per breed, with a total of 260 animals from each breed. The first three principal components explained 59.89% of the total variation, with PC1 (33.54%) clearly separating Bos indicus from Bos taurus lineages. Admixture analysis identified stable ancestral components and defined the genetic makeup of both pure and composite populations. The results showed extensive genetic diversity in some breeds and highlighted distinct genetic differences between Bos indicus and Bos taurus breeds. In addition, six composite breeds' admixture levels confirmed their origin and breed history, revealing a directional shift in ancestry proportions by a longitudinal increase in Brahman ancestry within tropical composites over time. Thus, the findings pave the way for more effective utilization of genetic diversity both within and across populations and provide a framework for designing multi-breed genetic evaluations and breeding programs to improve productivity and profitability in Australian beef production.

Animals↗
PubMed2026

Genome-Wide Differentiation, Inbreeding, and Candidate Selection Loci in Local Vietnamese Pig Breeds.

Vietnam harbors exceptional genetic diversity among at least 26 indigenous pig breeds. We analyzed genome-wide single-nucleotide polymorphism (SNP) data from 90 animals representing 15 local Vietnamese breeds and six Landrace pigs using principal component analysis, the windowed fixation index (FST), cross-population extended haplotype homozygosity (XP-EHH), within-population integrated haplotype score (iHS), and runs of homozygosity (ROHs). The population structure was consistent with a north-south differentiation axis, and Ba Xuyen showed elevated heterozygosity, providing suggestive evidence of a European genetic contribution; the f3 statistic was positive (f3 = +0.015), and formal evidence of admixture requires a significantly negative f3, so this criterion was not met. Integration of FST and XP-EHH identified GPC5, E2F6, NOS1, and TLR4 as top Northern candidate loci and CRYM/ZP2 as the leading Central candidate locus, and these windows were recovered at both the 90th and 95th percentile thresholds, indicating analytical robustness rather than independent biological validation. iHS was elevated at E2F6 in Northern breeds (|iHS| = 3.04) and at NOS1 across all regional groups (|iHS| = 2.66-3.36). Breed-level phenotypic XP-EHH, based on published breed descriptions and coat color rather than individual body-composition measurements, identified GALNT2 as a candidate shared across breed groups; HCAR1 and ATG10 as candidates specific to the extreme-fat/prolific breed group; and EFNA5 and HIPK2 as candidates specific to the medium-bodied breed group. ROHs identified Soc, Co, and Hung as breeds warranting particular attention in conservation planning due to elevated autozygosity. Because each breed was represented by only six individuals, and because no individual-level phenotypic measurements were available, all findings are reported as exploratory population-genomic signals requiring replication in larger cohorts. Overall, we describe genomic differentiation and candidate selection signatures among local Vietnamese pig breeds and provide a foundation for further genomic studies of these breeds.

Animals↗
PubMed2026

Genome-Wide SNP Characterisation of Three Kazakh Sheep Breeds: Kazakh Fat-Tailed Coarse-Wool, Degeres, and Etti Merino.

Kazakhstan's sheep portfolio underpins much of the country's mutton and wool production, yet several of its principal breeds remain genomically uncharacterised. The aim of this study was to characterise the genomic diversity, population structure, and global phylogenetic placement of three economically important Kazakh breeds and to determine whether they constitute separate gene pools requiring independent management. We present the first genome-wide SNP characterisation to include the Degeres (DE), the Etti Merino (EM), and the Kazakh fat-tailed coarse-wool (KKG) breeds simultaneously. A total of 1497 animals (DE = 354, EM = 642, KKG = 501) sampled across seven production households were genotyped and, after quality control, analysed at 42,279 SNPs, of which 22,766 LD-pruned markers were used for principal component analysis and AMOVA. We applied principal component analysis (PCA), pairwise FST, analysis of molecular variance (AMOVA), neighbour-joining phylogenetics, model-based ancestry estimation (ADMIXTURE), and Hill-number diversity profiling, and projected the breeds against the global Ovine SNP50 HapMap panel (74 reference breeds, 2819 animals; 37,685 shared SNPs). All three breeds retained uniformly high within-breed diversity (expected heterozygosity 0.413-0.417) with fixation indices at or near zero. AMOVA partitioned 94.03% of variance within breeds (&#x3a6;ST = 0.060, p < 0.001). PCA, phylogeny, and ADMIXTURE concordantly resolved three breed-specific clusters at K = 3, with a maximum interbreed FST of 0.038 within the study dataset. Against the global panel, EM was genetically closest to Merino and Merino-derived reference breeds (pooled FST = 0.017) and substantially more distant from Southwest Asian sheep (FST = 0.045), whereas DE and KKG showed the reciprocal pattern (FST = 0.027 and 0.020 to Southwest Asia, 0.052 to the Merino group). DE additionally displayed the heterozygote excess and partial admixture expected of an incompletely consolidated composite. These results delineate three distinct gene pools and carry direct implications for breed management and the conservation of genomic diversity in Kazakhstani sheep.

ADMIXTURE↗
PubMed2026

Genomic diversity, inbreeding, and selection signatures in duroc, landrace, and yorkshire pigs from a long-term closed breeding system.

Duroc (DD), Landrace (LL), and Yorkshire (YY) are among the most widely used commercial pig breeds, having undergone intense long-term selection within closed breeding systems. This study presents a comprehensive genomic analysis of genetic diversity, inbreeding patterns, and selection signatures in DD, LL, and YY populations that have been subject to close breeding for over 15 years. Genomic and pedigree data were available for 1,088 animals (DD&#x2009;=&#x2009;348, LL&#x2009;=&#x2009;276, YY&#x2009;=&#x2009;464), genotyped using the GenoBaits&#xae; Porcine 100&#xa0;K SNP panel. Principal component analysis and genetic diversity metrics revealed distinct population structures among the three breeds. Pairwise genetic differentiation supported this pattern, with DD showing the greatest divergence from LL (0.34&#x2009;&#xb1;&#x2009;0.24) and YY (0.33&#x2009;&#xb1;&#x2009;0.24), while LL and YY were more closely related (FST&#x2009;=&#x2009;0.22&#x2009;&#xb1;&#x2009;0.19). Linkage disequilibrium (LD) analysis further confirmed these differences, as DD exhibited the highest average r&#xb2; (0.34), followed by LL (0.28) and YY (0.25). Within-breed genetic diversity metrics, including observed heterozygosity (HO: 0.37 in DD, 0.39 in LL, 0.38 in YY), expected heterozygosity (HE: 0.36 in DD, 0.37 in LL, 0.38 in YY), and minor allele frequency (MAF: 0.27 in DD, 0.28 in LL, 0.29 in YY), indicated greater genetic variability in LL and YY compared to DD. Runs of homozygosity (ROH) analyses revealed different patterns of autozygosity, with DD exhibiting more long ROH indicative of recent inbreeding, while YY harbored a higher number of short ROH, suggestive of more ancient demographic events. ROH-based inbreeding coefficients (FROH) consistently exceeded pedigree-based estimates (FPED) across all breeds, highlighting the presence of recent or unrecorded inbreeding that pedigree data may not fully capture. According to Generation Proxy Selection Mapping (GPSM), 17, 1, and 12 significant SNPs were detected in DD, LL, and YY, respectively. Functional annotation of ROH islands and GPSM-significant loci revealed both breed-specific and overlapping QTLs related to traits such as growth, reproduction, and carcass. In general, the findings of this study contribute to a deeper understanding of the genomic consequences of long-term closed breeding and provide reference information to support consideration of breeding strategies that balance continued selection for productivity with the maintenance of genetic diversity in modern commercial pig populations.

Animals↗
PubMed2026

AI-integrated digital breeding for crop improvement.

Crop breeding increasingly depends on the effective integration and interpretation of large, heterogeneous datasets spanning genomic, phenotypic, multi-omics, and environmental layers. Conventional breeding approaches are often insufficient to capture the complex relationships among these data or to support timely selection decisions. Digital breeding can help address this limitation by complementing field experimentation, mixed models, and genomic prediction with the integration of biological data and computational prediction throughout the breeding process. In particular, the rapid advancement of artificial intelligence (AI) has improved the analysis of high-dimensional datasets and broadened its application to trait prediction, selection, and breeding design. Here, we review recent developments in AI-enabled digital breeding, encompassing genomic, phenomic, and multi-omics data generation and analysis, predictive modeling, explainable and generative AI, and data-driven breeding decision support. We further discuss emerging AI applications, their current contributions to crop research and breeding, and the major considerations affecting their reliable and practical implementation. Collectively, this review provides a structured understanding of the roles of AI across the digital breeding process and offers guidance for future methodological development and practical application in crop improvement.

artificial intelligence↗