Zinc (Zn) is an important nutrient in poultry and its deficiency has been linked with various disorders, in addition to depressed growth and performance. It is now recognised that Zn has a major role in antioxidation, growth and development, production, immunity and stress related issues. Supplementation of Zn can improve growth, augment immunity, enhance antioxidant capacity, increase endocrine secretion and interact with other minerals in the gut. In this review, some of the basic information regarding the importance and activity of Zn within the body and the addition of Zn in poultry diets is discussed.

Protein is the main limiting factor and the second most expensive feed component of poultry ration after energy. In many developing countries, poultry feed prices are consistently increasing because of the dependency on imported soybean meal. In order to decrease the dependency of the poultry feed sector on soybean meal it is necessary to find sustainable alternative protein sources. This review summarises recent findings on the nutritive value of maggot meal, earth worm meal, meal worms and silkworm meal and discusses their potential as an alternative protein source for poultry feed sector.

The present study was carried out to evaluate the effect of optimum and high ambient temperatures on biochemical parameter of four broiler strains. Broiler chicks (n = 242) of four different commercial strains (Ross, Hubbard, Cobb and Arber Acer) on day 15 were divided into two groups: thermo-neutral zone (TN) group and high ambient temperature zone (HAT) group. Chicks in TN group were housed at constant room temperature (25 °C ± 2 C° and RH 65 ± 5%) while chicks in HAT group were kept under HAT of summer. Chicks in each group were further divided into four subgroups, i.e., TN-Ross, TN-Hubbard, TN-Cobb, TN-Arber Acer and HAT-Ross, HAT-Hubbard, HAT-Cobb, HAT-Arber Acer. Each subgroup was further subdivided into four replicates having ten chicks per replicate. Blood was collected on day 21 and 42. Mean serum aspartate aminotransferase (AST), alanine amino transaminase (ALT), alkaline phosphates (ALP), glucose, cholesterol, triglyceride, and low-density lipoprotein (LDL) were significantly higher (P < 0.05) in HAT group, while total serum protein and high-density lipoprotein (HDL) were significantly higher (P < 0.05) in TN group. In TN zone group, significantly (P < 0.05) lower AST, ALT, glucose, cholesterol, triglyceride, and LDL and significantly (P < 0.05) higher HDL and total protein were recorded for Cobb and Hubbard strains. In HAT zone group, significantly (P < 0.05) lower AST, ALT, glucose, cholesterol, triglyceride, and LDL and significantly (P < 0.05) higher HDL and total protein were recorded for Ross and Arber Acer strains. The findings of the present study suggested that Ross and Arber Acer strains were more tolerant to summer HAT of tropical areas than Cobb and Hubbard, while Cobb and Hubbard strains were more effective in TN environment.

L-carnitine (B-hydroxy-Y-N-trimethyl aminobutyrate) is a water-soluble product, found in animals, plants and microorganisms. Its synthesis takes place from two important amino acids, lysine and methionine. Essentially, L-carnitine has an intermediary role in metabolism. It promotes energy metabolism for cell and regulates co-enzyme A concentration in cystosol and mitochondria, which are important in glucose and lipid metabolism. L-carnitine was first isolated from the chicken embryo in a significant amount, but is absent in the egg. Under normal physiological conditions, the endogenously synthesised levels are sufficient for normal growth and functions. Its requirements are increased in stressful conditions and during metabolic and physiological higher demands, such as growth and laying periods. L-carnitine increases energy production, fat metabolism and improves immune status in birds, which is energy demanding. In this review, several aspects of the beneficial effects of dietary supplementation of L-carnitine on poultry health and production are briefly summarised.