It was hypothesized that differences in production system and muscle type may influence the formation of lipid oxidation products (LOP) as well as protein oxidation (protein carbonyl compounds, PCC) during the in vitro gastrointestinal digestion of chicken meat. To test our hypothesis, we investigated the formation of LOP and PCC after heating and in vitro gastrointestinal digestion of conventional and organic chicken breast and thigh meat and Wooden Breast meat. Prior to the in vitro digestion, thigh and breast meat was minced and heated. Digests of organic thigh meat had significantly higher levels of all LOP measured compared to conventional thigh meat (between +37% and +173%). Lower levels of LOP were found in digests of breast meat regardless of the production system and Wooden Breast phenotype. LOP correlated positively with heme-Fe and polyunsaturated fatty acids, negatively with anserine, and not with carnosine and α-tocopherol. PCC levels were significantly higher in thigh meat than in breast meat after heating (+43%) and digestion (+25%), irrespective of the production system. Overall, organic thigh meat exhibited the highest oxidative sensitivity during digestion. The cut-dependent differences in composition and oxidative susceptibility between organic and conventional chicken highlight the need for further research to assess potential health implications.

It was hypothesized that differences in production system and muscle type may influence the formation of lipid oxidation products (LOP) as well as protein oxidation (protein carbonyl compounds, PCC) during in vitro gastrointestinal digestion of chicken meat. To test our hypothesis, we investigated the formation of LOP and PCC after heating and in vitro gastrointestinal digestion of conventional and organic chicken breast and thigh meat and Wooden Breast meat. Prior to the in vitro digestion, thigh and breast meat was minced and heated. Digests of organic thigh meat had significantly higher levels of all LOP measured compared to conventional thigh meat (between +37% and +173%). Lower levels of LOP were found in digests of breast meat regardless of production system and Wooden Breast phenotype. LOP levels were associated with variations in heme-Fe, polyunsaturated fatty acids, carnosine, anserine and α-tocopherol. PCC levels were significantly higher in thigh meat than in breast meat after heating (+43%) and digestion (+25%), irrespective of the production system. The cut-dependent differences in composition and susceptibility to oxidation during in vitro digestion between organic and conventional chicken meat in the present study warrant further research to allow a comprehensive assessment of the health implications.

Ostrich farming has emerged as a significant contributor to the livestock industry, driven by the high value of its meat, hides, feathers, and oil in international markets. With an average egg production of 40 eggs per season and yielding 58.59% carcass on live weight, ostriches offer substantial economic benefits. The nutritional needs of ostriches evolve across different life stages, impacting growth and reproductive performance. As herbivores capable of digesting high-fiber diets, ostriches thrive on roughage and pasture, with a digestive system similar to other poultry. Essential nutrients, including 20-24% crude protein (CP) and 12-19% crude fiber, are critical for optimal development, particularly in early growth, where their feed conversion ratio is 2:1. As ostriches reach sexual maturity, maintaining a diet rich in amino acids, vitamins, and carbohydrates becomes vital for optimizing fertility and reproductive performance. This review provides a detailed overview of ostrich nutrient requirements across different growth stages, focusing on how energy and protein levels affect overall growth and productivity. It also explores the importance of feeding management practices in enhancing ostrich health and performance, offering insights for improving commercial ostrich farming.

This study aimed to compare the oxidative stability of chicken breast and thigh meat from four distinct production systems differing in their level of intensification using an accelerated oxidation display model. The systems differed in housing conditions and growth rate of the genotypes: indoor and fast-growing (Ind_Fast), indoor and fast-medium-growing (Ind_Fastmed), outdoor and medium-growing (Out_Med), and outdoor and slow-growing (Out_Slow). Sixty mixed-sex broilers were randomly selected from 20 farms in Belgium (5 farms per production system × 3 chickens per farm). On day 2 post-slaughter, skinless breast and thigh meat from each chicken were ground separately. Forty g of ground sample was stored under light (1,600-2,200 lux, 2-4°C) for 168 h, while the remaining ground meat was used for composition analyses. Color CIE L* a* b* coordinates were measured at 0, 48, 96 and 168 h, with total color change (ΔE) calculated at the end of the display period. Lipid oxidation (thiobarbituric acid reactive substances, TBARS), and protein oxidation (protein carbonyl compounds, PCC) were measured at the end of display. In both breast and thigh, indoor-raised chickens exhibited lighter color, characterized by higher L*, and lower a* and b* (P < 0.001) compared to outdoor-raised chickens. However, outdoor-raised chickens showed greater ΔE compared to indoor counterparts, indicating lower color stability. TBARS were higher in breast meat from Out_Slow than Ind_Fast chickens (P < 0.05), whereas there were no significant differences between production systems in thigh meat. The TBARS values remained below the 1 mg/kg threshold for off-flavors in both meat cuts. PCC was not affected by production system in either meat cut. These differences in oxidative stability may be due to production system-related variation in fatty acid composition, heme iron concentration, and antioxidant status, with effects depending on the meat cut. The findings suggest that the observed variation in oxidative stability reflects the combined influence of multiple production system characteristics rather than the effect of any single factor.