Veterinarija ir Zootechnika

The aim of this study was to evaluate the effect of dietary supplementation with maca (Lepidium meyenii) root powder on selected chemical, nutritional, and technological parameters of rabbit meat, focusing on musculus vastus lateralis (MVL) and musculus longissimus dorsi (MLD). Fifty-four adult male rabbits of the Nitra breed were divided into three groups: a control group without supplementation and two experimental groups receiving 0.3% (E1) and 0.6% (E2) maca root powder in the feed ration for 13 weeks. In the MLD muscle, protein content was significantly higher in group E2 compared with both the control and E1 groups. The content of omega-6 fatty acids was also significantly increased in group E2, while no differences were observed in saturated, monounsaturated, and omega-3 fatty acids. In both muscles, the pH values of meat during storage were significantly lower in E2 compared with the control. Meat colour was also affected, with higher yellowness (b*) values observed in experimental groups after storage. No significant differences were detected in lipid oxidation parameters among groups. Overall, maca supplementation, particularly at 0.6%, enhanced the nutritional quality of rabbit meat by increasing protein and omega-6 fatty acid content, without compromising oxidative stability.

A total of 66 post-weaned rabbits (35th day of age meat line M91 a P91 hybrid) were randomly divided into 3 groups for fattening experiment, kept in standard metal cages with two animals per cage. Rabbits were fed with commercial diet (control group, CG), or supplemented with 5% of agricultural by-products linseed cake (EG1), or supplemented with 10% linseed cake (EG2). The experiment lasted 42 days, until the animals attained the slaughtering weight ≈2.5 kg. Individual blood was sampled from a total of 30 rabbits, and five animals from each group were slaughtered at the end of experiment, for the evaluation of animal welfare and meat quality. Feeding of linseed cake substances in rabbits did not negatively influence zootechnical parameters, growth performance and slaughter traits; it had no negative effect on rabbit’s blood biochemical profile either. Experimental diets with 5% linseed cake improved feed conversion ratios, without significantly impacting the final weight of animals. The dietary supplementation positively influenced the meat fatty acids profile, in particular polyunsaturated fatty acids (linoleic acid and CLA), indicating enhanced nutritional quality of the meat as a functional food. Overall, the use of linseed cake, a sustainable agricultural by-product, is a promising dietary strategy to improve the nutritional value of rabbit meat and support efficient, welfare-conscious rabbit production.

We designed and tested the polymorphic gene MC4R in relation to live weight and weight gain of Slovak native chicken breed Oravka kept at the farm of NAFC-RIAP Nitra, which was selected for future breeding by phenotype. We monitored the weight of chickens at the age of 5, 12 and 20 weeks and calculated the weight gain for each period. The design of detection oligonucleotide primers for MC4R gene detection in DNA samples was based on the sequence available in GenBank, NCBI. Statistical analysis was done using the SAS 9.2 Stat software. We identified the GG genotype in only one hen. The number of GT heterozygotes was significantly higher in both hens (110) and roosters (16) after a long-time directive selection. The TT genotype was found in 9 hens and 5 roosters. The GG genotype was detected with a frequency of 0.71%, the GT genotype with a frequency of 89.36%, and the TT genotype with a frequency of 9.93%. The frequency of allele G was 0.454 ± 0.030; and that of allele T was 0.546 ± 0.030. At the age 12 weeks, homozygous hens were heavier (1111.33 ± 44.96 g) than heterozygous hens (1108.15 ± 13.17 g). Similarly, rooster homozygotes were on average heavier (1581.47 ± 59.11 g) than heterozygotes (1389.69 ± 34.40 g). WG 1 was significantly higher in homozygote animals TT (P < 0.01). The same pattern was also observed at the age of 20 weeks. Homozygous TT animals achieved a higher average weight, i.e., the weight of hens was 1947.25 ± 74.35 g, the weight of roosters was 2719.91 ± 87.75 g; meanwhile, for heterozygous animals, the weight of hens was 1888.78 ± 21.78 g, and the weight of roosters was 2525.99 ± 56.89 g. We concluded that in the selected Oravka “mutant” allele T is preferred.