Digestibility of Meat Mineral and Proteins from Broilers Fed with Graded Levels of Chlorella vulgaris

Dietary supplementation with Chlorella vulgaris in broiler chickens submitted to heat-stress: effects on growth performance and meat quality

Heat stress can greatly challenge growth and meat quality of broiler chickens where research is looking for sustainable ingredients, such as microalgae, that could also alleviate its negative impacts. Thus, in the present study, 576 1-D-old chicks (Ross 308) were housed until commercial slaughtering (42 D) in 36 pens in 2 rooms of a poultry house, according to a full factorial design encompassing 2 room temperatures (standard vs. high), 2 sexes (females vs. males), and 3 dietary treatments, that is, diet C0 (control diet), diet C3, and diet C6 containing 0, 3, and 6%, respectively, of C. vulgaris meal replacing the same quantities of soybean meal. The highest inclusion level of C. vulgaris decreased feed intake (P < 0.001) and body weight (P < 0.0001) compared to the control diet; it increased yellow and red indexes (P < 0.0001) of the breast muscle, besides the proportion of n3 polyunsaturated fatty acids (PUFA) (P = 0.028). Heat stress decreased feed intake (P = 0.001), breast (P = 0.001) and p. major yields (P = 0.036), and increased meat pH (P= 0.008) and cooking losses (P < 0.001), umami (P = 0.021) and brothy flavor (P < 0.001), and the proportion of n3 PUFA rates (P = 0.027), while reducing the contents of several amino acids in the breast meat (P ≤ 0.05). Compared to females, males displayed higher feed intake and growth, and more favorable feed conversion (P < 0.001). Carcass and p. major yields were greater in females (P < 0.001) which also showed a higher occurrence of spaghetti meat compared to males (P < 0.001). In conclusion, C. vulgaris can be used to replace until 3% of soybean meal in diets for broiler chickens without negative implications, while positively affecting breast meat color according to consumers' preferences. However, the microalgae inclusion did not mitigate the negative effects of a chronic heat stress on growth performance nor reduced the occurrence of any myopathies.

Microalgae as an Alternative Mineral Source in Poultry Nutrition

This review explores the potential of microalgae as a sustainable and nutritionally rich alternative for mineral supplementation in poultry diets, addressing both the opportunities and challenges in this emerging field. Poultry nutrition, pivotal to the health and productivity of birds, traditionally relies on inorganic and organic mineral sources which, while effective, raise environmental and economic concerns. Microalgae offer a promising solution with their high contents of essential minerals, proteins, vitamins, and bioactive compounds. This review delves into the nutritional profiles of various microalgae, highlighting their rich contents of minerals which are crucial for physiological processes in poultry. It examines the bioavailability of these minerals and their impact on poultry health and productivity. Furthermore, it evaluates the environmental sustainability of microalgae cultivation and acknowledges the challenges in using microalgae in poultry diets, particularly in terms of the economic viability of large-scale production and the consistency of nutrient composition. It discusses the importance of rigorous safety assessments and regulatory compliance, given the potential risks of toxins and heavy metals. Overall, this analysis aims to provide a clear understanding of the role microalgae could play in poultry nutrition and address sustainability challenges in animal agriculture while also considering future perspectives and advancements needed in this field.

Carcass Yields and Meat Composition of Roosters of the Portuguese Autochthonous Poultry Breeds: "Branca", "Amarela", "Pedrês Portuguesa", and "Preta Lusitânica"

Poultry meat is an important part of the human diet, and the valorisation of autochthonous breeds is a determinant for the sustainability of the rural areas. The increasing demand for niche products demands for better knowledge of the carcass characteristics and meat quality of these local populations. The present study aims to characterise the roosters' meat from the "Branca" (BR), "Amarela" (AM), "Pedrês Portuguesa" (PP), and "Preta Lusitânica" (PL) breeds. A total of 80 birds (n = 20 per breed) between 38 and 42 weeks old were slaughtered. The physicochemical and nutritional composition were determined in the breast and drumstick meat. The meat of the PL breed had a higher (p ≤ 0.05) pH value, the AM meat revealed a water-holding capacity (WHC) of superior value and moisture content (p ≤ 0.05), while the BR breed had the highest (p ≤ 0.05) ash content. On the other hand, it was observed that the PP meat had a higher (p ≤ 0.05) yellowness index (b*). The breast meat exhibited, in all breeds, a lower pH value, WHC, redness (a*), and lipid content and greater (p ≤ 0.05) lightness (L*), b*, moisture, and ash and protein contents compared to the drumstick. Furthermore, it presented higher (p ≤ 0.05) K, P, and Mg contents and a superior proportion of total and sensorial relevant amino acids. Regarding the fatty acid profile, the breed differences were more significant in the drumstick, with the AM breed lipids presenting a higher (p ≤ 0.05) percentage of MUFAs in the fat, a lower atherogenic index, and a higher (p ≤ 0.05) value for the hypocholesterolemic/hypercholesterolemic fatty acids ratio, while the BR breed lipids presented a higher (p ≤ 0.05) percentage of PUFAs and PUFAs/SFAs ratio and a lower n-6/n-3 ratio. Considering the results obtained, it can be concluded that the meat from these breeds is a wholesome dietary option, distinguished by a favourable overall nutritional composition marked by elevated protein content, reduced lipid amounts, and amino and fatty acid profiles with desirable nutritional indices.

White and honey Chlorella vulgaris: Sustainable ingredients with the potential to improve nutritional value of pork frankfurters without compromising quality

This study aimed to evaluate the effect of the chlorophyll-deficient microalgae mutants, honey (yellow) and white Chlorella vulgaris, (3%) on the nutritional, physicochemical, microbiological, and sensory characteristics of frankfurters. The presence of microalgae resulted in increased PUFA content and higher PUFA/SFA ratio, but lower n-6/n-3 ratio and lipid indices (P < 0.05). C. vulgaris inclusion in frankfurters increased (P < 0.05) Na, K, Ca, P, and Zn and improved the Na/K ratio, but lowered Mn, and in the case of white C. vulgaris, Cu content, compared to the control. The higher protein content decreased water release from emulsions elaborated with microalgae. White C. vulgaris inclusion decreased cohesiveness and springiness of the frankfurters. Due to the presence of pigment, microalgae inclusion led to a decrease in redness and an increase in yellowness of frankfurters. The presence of microalgae resulted in lower (P < 0.05) bacterial counts and did not affect TBARs during storage. The addition of microalgae in frankfurters produced acceptable sensory characteristics but resulted in lower scores compared to reference products.