Single Nucleotide Polymorphism in the LDHA Gene as a Potential Marker for the Racing Performance of Pigeons

The objective of the present study was to investigate the relationship between the g.2582481G>A, g.2583935G>A and g.2584057C>T single nucleotide polymorphisms (SNPs) within the lactate dehydrogenase A gene (LDHA) coding for lactate dehydrogenase isoform A and the racing performance of homing pigeons. As a measure of racing performance, we used the mean values of ace points won by individual birds during the whole season. The estimated heritability of the racing performance of pigeons was relatively low (h2=0.0596; SE=0.0249). The analysis performed for all race reports together showed that the factors such as gender, weather conditions at the start and at the end of the race affect the analyzed trait. Of the 3 single nucleotide polymorphisms, only the effect of the g.2582481G>A genotype on the performance of racing pigeons was significant. Statistical analysis indicated the difference in the value of ace points between the animals of GG and GA genotypes for the g.2582481G>A SNP. The study showed that the genotype homozygous for g.2582481A is linked to the highest mean value of ace points. Consequently, the relationship between the genotype for g.2582481G>A and the racing performance was shown

Metabolic and endocrine profiles and reproductive parameters in dairy cows under grazing conditions: effect of polymorphisms in somatotropic axis genes

<p>Abstract</p> <p>Background</p> <p>The present study hypothesized that GH-AluI and IGF-I-SnabI polymorphisms do change the metabolic/endocrine profiles in Holstein cows during the transition period, which in turn are associated with productive and reproductive parameters.</p> <p>Methods</p> <p>Holstein cows (Farm 1, primiparous cows, n = 110, and Farm 2, multiparous cows, n = 76) under grazing conditions were selected and GH and IGF-I genotypes were determined. Blood samples for metabolic/endocrine determinations were taken during the transition period and early lactation in both farms. Data was analyzed by farm using a repeated measures analyses including GH and IGF-I genotypes, days and interactions as fixed effects, sire and cow as random effects and calving date as covariate.</p> <p>Results and Discussion</p> <p>Frequencies of GH and IGF-I alleles were L:0.84, V:0.16 and A:0.60, B:0.40, respectively. The GH genotype was not associated with productive or reproductive variables, but interaction with days affected FCM yield in multiparous (farm 2) cows (LL yielded more than LV cows) in early lactation. The GH genotype affected NEFA and IGF-I concentrations in farm 1 (LV had higher NEFA and lower IGF-I than LL cows) suggesting a better energy status of LL cows.</p> <p>There was no effect of IGF-I genotype on productive variables, but a trend was found for FCM in farm 2 (AB cows yielded more than AA cows). IGF-I genotype affected calving first service interval in farm 1, and the interaction with days tended to affect FCM yield (AB cows had a shorter interval and yielded more FCM than BB cows). IGF-I genotype affected BHB, NEFA, and insulin concentrations in farm 1: primiparous BB cows had lower NEFA and BHB and higher insulin concentrations. In farm 2, there was no effect of IGF-I genotype, but there was an interaction with days on IGF-I concentration, suggesting a greater uncoupling somatropic axis in AB and BB than AA cows, being in accordance with greater FCM yield in AB cows.</p> <p>Conclusion</p> <p>The GH and IGF-I genotypes had no substantial effect on productive parameters, although IGF-I genotype affected calving-first service interval in primiparous cows. Besides, these genotypes may modify the endocrine/metabolic profiles of the transition dairy cow under grazing conditions.</p

Application of selection mapping to identify genomic regions associated with dairy production in sheep

In Europe, especially in Mediterranean areas, the sheep has been traditionally exploited as a dual purpose species, with income from both meat and milk. Modernization of husbandry methods and the establishment of breeding schemes focused on milk production have led to the development of "dairy breeds." This study investigated selective sweeps specifically related to dairy production in sheep by searching for regions commonly identified in different European dairy breeds. With this aim, genotypes from 44,545 SNP markers covering the sheep autosomes were analysed in both European dairy and non-dairy sheep breeds using two approaches: (i) identification of genomic regions showing extreme genetic differentiation between each dairy breed and a closely related non-dairy breed, and (ii) identification of regions with reduced variation (heterozygosity) in the dairy breeds using two methods. Regions detected in at least two breeds (breed pairs) by the two approaches (genetic differentiation and at least one of the heterozygosity-based analyses) were labeled as core candidate convergence regions and further investigated for candidate genes. Following this approach six regions were detected. For some of them, strong candidate genes have been proposed (e.g. ABCG2, SPP1), whereas some other genes designated as candidates based on their association with sheep and cattle dairy traits (e.g. LALBA, DGAT1A) were not associated with a detectable sweep signal. Few of the identified regions were coincident with QTL previously reported in sheep, although many of them corresponded to orthologous regions in cattle where QTL for dairy traits have been identified. Due to the limited number of QTL studies reported in sheep compared with cattle, the results illustrate the potential value of selection mapping to identify genomic regions associated with dairy traits in sheep

Fermentation products of Cordyceps militaris enhance performance and modulate immune response of weaned piglets

The aim of this study was to investigate the effect of supplementation of Cordyceps militaris fermentation products (CMF) on growth performance and immunocompetence of piglets. The study involved three groups of animals, which were supplemented with CMF (500, 1000 and 1500 μg/kg feed), and a control group. CMF supplementation significantly increased growth performance in weaned piglets. Bodyweight gain, average daily gain and feed intake in animals supplemented with 1000 μg CMF/kg feed were significantly higher in comparison with the control group. In addition, CMF supplementation only significantly increased the synthesis of Th1 cytokines, as indicated by the levels of IL-2 and IFN-γ. The piglets fed with the CMF supplement displayed an increased cellular immune response. Indeed, alveolar macrophages isolated from piglets supplemented with 1000 and 1500 μg CMF/kg feed had significantly higher chemotactic and phagocytic indices than those isolated from piglets that received the control feed or feed supplemented with 500 μg CMF/kg. In relation to the absence of effect on Th2 cytokines, the CMF supplement had no effect on hog cholera antibody titre. In summary, feed supplementation with CMF improves growth performance and enhances cell-mediated immunity. CMF supplementation may thus be useful at weaning to counteract physiological and immunological stress during this period.Keywords: Cellular immunity, growth performance, humoral immunity, Th1/Th2 cytokine