Content of amino acids and biogenic amines in stored meat as a result of a broiler diet supplemented with ß-alanine and garlic extract.

Poultry meat is a highly esteemed product among consumers. However, the emphasis on increasing body weight has led to a rise in the proportion of rapidly shrinking fibers, adversely affecting the quality and shelf life of poultry meat. With a growing awareness of dietetics among consumers, there is an increasing challenge to produce chicken meat that is not only free of antibiotics but also beneficial for dietary and health reasons. Biogenic amines (BA) can serve as indicators of meat freshness and quality. While they play vital roles in the body, excessive consumption of BA can have toxic and carcinogenic effects. The objective of this study was to examine the impact of supplementing feed with garlic extract and ß-alanine (ß-Ala) on the formation of BA and amino acid (AA) levels in the breast and leg muscles of chickens stored under aerobic chilling conditions. The muscles were obtained from chickens fed with garlic extract and ß-Ala in quantities of 0.5 and 2% for each additive, as well as 0.5 and 2% of their combination. Analyses were conducted on d 1, 3, 5, 7, and 10 of storage. ß-Ala supplementation increased the proportion of this AA in breast (P < 0.01) and leg muscles (P < 0.01), along with a rise in the proportion of nonessential AA (NEAA; sum of aspartic, aspartic acid, glutamic, glutamic acid, serine, ß-Ala, and proline) (P < 0.01). The levels of BA changed during storage in breast and leg muscles (P < 0.001). The applied diet significantly influenced the formation of putrescine (P = 0.030), phenylethylamine (P = 0.003), agmatine (P = 0.025), and total BA (P < 0.001) in breast muscles. On the 10 d of storage, the breast muscles exhibited the lowest BA index (BAI) in the group, with a diet supplemented with 0.5% garlic extract and 0.5% ß-Ala (P < 0.05). The leg muscles showed a similar BA trend as the breast muscles. These supplements may be utilized in production to augment the protein content of chicken muscles and potentially decrease the BAI index during meat storage.

Effect of copper nanoparticles on the mineral content of tissues and droppings, and growth of chickens.

We hypothesised that copper nanoparticles (NanoCu), because of their high physicochemical reactivity and bioavailability, could be used in much smaller quantities than bulk Cu, consequently reducing excretion of Cu into the environment. The objective of the study was to evaluate the effects of various levels of NanoCu on the development and growth of broiler chickens, in order to establish an optimum level of NanoCu dietary supplementation. Broiler chickens were randomly divided into five groups of 10 birds each. The control group received 7.5 mg Cu/kg feed (standard level) as CuSO4, while groups fed with complexes of NanoCu and starch received 25%, 50%, 75% and 100% of the standard level of Cu used in the control group. Chicken growth and excretion of Cu, Fe and Zn were measured during the growth period from d 7 to 42. At d 42, the slaughter characteristics, the content of Cu, Fe and Zn in the breast muscle and liver, and the oxidative status were analysed. The results indicate that using NanoCu can reduce the standard level of Cu from CuSO4 supplementation by 75% without jeopardising animal growth, and at the same time significantly decreasing Cu excretion into the environment.

ß-Alanine as a factor influencing the content of bioactive dipeptides in muscles of Hubbard Flex chickens.

BACKGROUND: The aim of this study was to determine the effect of various doses of ß-alanine administered in feed mixtures and of heat treatment on changes in the contents of dipeptides anserine and carnosine in meat of fast-growing Hubbard Flex chickens. RESULTS: The study demonstrated a significant effect of dietary administration of ß-alanine on anserine content in breast muscles and on carnosine content in leg muscles of the chickens. A successive increase in dipeptide content was observed with increasing ß-alanine content in the feed mixture. As a result of heat treatment, a significant (P ≤ 0.01) increase was observed in the anserine content of both breast and leg muscles: over twofold higher anserine content was detected in heat-treated muscles compared with raw muscles. The study showed that interesting effects might occur during ß-alanine administration to feed mixtures for chickens, especially including increased contents of anserine and carnosine in skeletal muscles of the birds. CONCLUSION: Taking into account the well-documented health-promoting effect of histidine dipeptides and possibilities of increasing their contents in the body by supplementation with ß-alanine, anserine and carnosine might be considered as potential components of functional foods.

Effect of addition of "Greenline" preparations to feed mixtures for broilers on the composition of their intestinal microflora.

The current study deals with the possibility of replacing the antibiotic growth stimulator avilamycin, a mixture of oligosaccharides of the orthosomycin group, with the herbal preparations Greenline 1 and 2. The microbiological part of the study embraced examination of the intestinal microflora of broilers. The birds in the study belonged to four experimental groups, distinguished on the basis of feed supplements used. For the microbiological determination five birds from each group were selected at random and the contents of their small intestine was examined for given groups of microorganisms. The remaining birds in each group were examined and evaluated on the basis of zootechnical indices. Our results suggest that Greenline 1 efficiently eliminates certain pathogenic bacteria, above all lactose-positive bacteria belonging to the family Enterobacteriaceae and Staphylococci. It seems that the presence of Greenline 1 in the feed mix used enhances the colonisation of the mucous membrane of the studied chicken with Lactobacillus lactic acid bacteria. This is indicated by the considerably higher number of these bacteria in the small intestine of the birds receiving the supplement Greenline 1.