Effect of Lighting Methods on the Production, Behavior and Meat Quality Parameters of Broiler Chickens.

Many farms have been replacing traditional lighting sources with light-emitting diode (LED) bulbs because of technological modernization. We aimed to investigate the effects of incandescent lighting (IL) and LED lighting on Cobb 500 broiler chickens for six weeks. Production parameters (body weight, feed consumption, feed conversion ratio), calculated slaughter values (yield%, relative breast%, thigh%) and breast meat quality parameters (pH at 45 min and 24 h postmortem, color, drip loss, kitchen equipment losses, shear force, meat composition) were recorded. Non-stop recordings were used to analyze the behavior of the birds during several periods of rearing. The LED group was significantly better in the body weight parameter between week 1 and 5 and the feed conversion ratio between week 2 and 3. The most significant difference in behavior was observed in the middle of the rearing period. The chickens in the LED group spent more time eating, drinking and interacting, and rested less. There was no difference in the meat quality parameters; only shear force was significantly lower in the LED group (1781.9 g/s vs. 2098.8 g/s). According to our results, LED lighting can bring about positive changes in animal production efficiency, behavior and other important characteristics for meat consumers.

Association of myostatin gene polymorphism with echocardiographic and muscular ultrasonographic measurements in Hungarian thoroughbreds horses.

The g.66493737C/T polymorphism of the myostatin gene (MSTN) majorly influences muscle fiber composition and best race distance of Thoroughbreds. Thus, a better understanding of this process may lead to superior genetic exploitation for maximizing Thoroughbred athletic potential. Our objective is to investigate whether myostatin genotypes are associated with muscular development and cardiac variables of Thoroughbreds. Echocardiography and muscular ultrasonography were performed on three groups having C/C, C/T, and T/T genotypes, respectively. Each group consisted of 22 animals. Homogeneity of variance between the groups was checked by Levene's test. Multivariate analysis of variance was applied to determine differences in measured variables vs. MSTN genotypes. Fascicle length of anconeus and thickness of triceps brachii muscles showed significant differences between C/C and T/T genotypes (pFascicle-length-of-anconeus = 0.004, pthickness-of-triceps-brachii < 0.001). According to the primary outcome, there are associations between myostatin genotypes and cardiac variables. Aortic diameter at the sinus of Valsalva (end-diastole and end-systole) and aortic diameter at the valve (end-systole) indicated significant differences between C/C and T/T genotypes (paortic-diameter-at-the-sinus-of-Valsalva-end-diastole = 0.015, paortic-diameter-at-the-sinus-of-Valsalva-end-systole = 0.011, paortic-diameter-at-the-valve-end-systole = 0.014). Pearson correlation effect sizes were rFascicle-length-of-anconeus = 0.460, rthickness-of-triceps-brachii = 0.590, raortic-diameter-at-the-sinus-of-Valsalva-end-diastole = 0.423, raortic-diameter-at-the-sinus-of-Valsalva-end-systole = 0.450, and raortic-diameter-at-the-valve-end-systole = 0.462. C/C genotypes gave 22.1, 12.2, 6.3, 6.0, and 6.7% higher values compared to T/T genotypes, respectively. Differences regarding aortic diameter between genotype groups support the hypothesis that C/C animals have consequently increased cardiac output and aerobic capacity.

The Role of PRLR Gene Polymorphisms in Milk Production in European Wild Rabbit (Oryctolagus cuniculus).

One of the problematic points of rabbit breeding is that the nutritional requirements of the kits are not fully satisfied by the does' milk production from the third week of lactation onwards. The prolactin receptor gene has a significant effect on reproductive processes, and its polymorphisms have been associated with milk production in several species (cattle, goats, sheep, and buffalo). The European wild rabbit (Oryctolagus cuniculus), has a more diverse genetic background compared to domesticated lines. In the course of our study, sequencing of the 1210 bp long segment of the PRLR gene promoter region was accomplished. We detected four point mutations (SNP1-407G > A, SNP2-496G > C, SNP3-926T> and SNP4-973A > C) and one microsatellite at position 574. In our population, the four SNPs were segregated into four genotypes: AACCCCCC, GGGGTTAA, AAGGTTAC, and GGGGTCAC. Our results show that the genotype in the homozygous form is associated with higher milk production (1564.7 ± 444.7 g) compared to the other three genotypes (AACCCCCC 1399.1 ± 326.8 g; GTGACCTT 1403.8 ± 517.1 g; GGGGTCAC 1220.0 ± 666.2 g), and the short microsatellite repeat (167 bp) also coincides with significantly higher milk production (1623.8 ± 525.1 g). These results make the marker-assisted selection possible also for domesticated lines.

Position of Hungarian Merino among other Merinos, within-breed genetic similarity network and markers associated with daily weight gain.

OBJECTIVE: In this study, we aimed to position the Hungarian Merino among other Merino-derived sheep breeds, explore the characteristics of our sampled animals' genetic similarity network within the breed, and highlight single nucleotide polymorphisms (SNPs) associated with daily weight-gain. METHODS: Hungarian Merino (n = 138) was genotyped on Ovine SNP50 Bead Chip (Illumina, San Diego, CA, USA) and positioned among 30 Merino and Merino-derived breeds (n = 555). Population characteristics were obtained via PLINK, SVS, Admixture, and Treemix software, within-breed network was analysed with python networkx 2.3 library. Daily weight gain of Hungarian Merino was standardised to 60 days and was collected from the database of the Association of Hungarian Sheep and Goat Breeders. For the identification of loci associated with daily weight gain, a multi-locus mixed-model was used. RESULTS: Supporting the breed's written history, the closest breeds to Hungarian Merino were Estremadura and Rambouillet (pairwise FST values are 0.035 and 0.036, respectively). Among Hungarian Merino, a highly centralised connectedness has been revealed by network analysis of pairwise values of identity-by-state, where the animal in the central node had a betweenness centrality value equal to 0.936. Probing of daily weight gain against the SNP data of Hungarian Merinos revealed five associated loci. Two of them, OAR8_17854216.1 and s42441.1 on chromosome 8 and 9 (-log10P>22, false discovery rate<5.5e-20) and one locus on chromosome 20, s28948.1 (-log10P = 13.46, false discovery rate = 4.1e-11), were close to the markers reported in other breeds concerning daily weight gain, six-month weight, and post-weaning gain. CONCLUSION: The position of Hungarian Merino among other Merino breeds has been determined. We have described the similarity network of the individuals to be applied in breeding practices and highlighted several markers useful for elevating the daily weight gain of Hungarian Merino.