No abstract

The effect of sodium butyrate on various bodily parameters of broilers such as performance, gut microflora, gut morphology, and immunity is reviewed in order to highlight its importance as an alternative to antibiotic growth promoters. Sodium butyrate is used as a source of butyric acid, which is known for its beneficial effects in the gut in monogastrics. Sodium butyrate is available in uncoated and entericcoated forms protected with fat or fatty acid salts. Varying results in productive performance, gut microbes, and gut morphology have been reported in the literature in response to supplementation of broiler diets with uncoated and fatcoated types of sodium butyrate. However, sodium butyrate has shown pronounced effects on immunity of chickens that are not fully understood yet. Although there are contrasting results of sodium butyrate in chicken, further research is needed using the sodium butyrate coated with the salts of fatty acids.

The present study was conducted to investigate the influence of different levels of dietary phytogenic feed additive (PFA) on growth performance, caecal microbiota, and intestinal morphology of broilers. A total of 480 Ross-308 one-day-old male broilers chicks (body weight 43+3 g) were randomly assigned to 32 replicate pens of four experimental groups, each experimental group consisting of 8 replicates (each replicate pen consisting of 15 chicks). A basal diet was formulated based on corn and soybean meal that was fed to the control group. Other dietary treatments received a commercial PFA at 100 mg/kg (PFA100), 125 mg/kg (PFA125), and 150 mg/kg (PFA150). Body weight gain, feed intake, and feed conversion rate of broilers were recorded on 1-21, 22-42, and 1-42 days of age. One bird was slaughtered on the 21 st and 42 nd days and caecal contents were aseptically collected. Jejunal tissue samples were also collected on the same days. Total aerobic bacteria, coliforms, Escherichia coli, and lactobacilli were counted in the caecal contents. Villus height, villus diameter, crypt depth, muscular thickness, and goblet cell number per villus were recorded. There was no difference among the dietary treatments for growth performance and caecal microbe populations at any phase. However, the dietary PFA supplementation increased the villus height, villus width, muscularis thickness, and reduced the crypt depth and goblet cell number per villus in broilers compared to those fed control diets. In conclusion, this study suggests that dietary supplementation of a PFA consisting of blend of different spices and essential oils did not improve growth performance and caecal microbial populations despite a positive improvement in the jejunal morphometry of broilers.

Abstract. The aim of study was to assess the growth performance, meat quality, and fatty acid composition of meat-type guinea fowl fed balanced commercial diets under two different feeding programs, similar to those for slaughter turkeys and broiler chickens, respectively. A total of 80 4-week-old meat-type guinea fowl divided into two groups (four replicates per group; 10 birds in each replicate) were raised for 14 weeks. One group received commercially available diets in a three-phased program (TM group), whereas the other group was fed commercial diets in a two-phased program (CM group). Growth-performance-related traits were recorded. At the end of rearing (14 weeks of age), eight birds from each group were slaughtered. Carcass yield and technological traits of meat (pH, color, water-holding capacity, natural and thermal loss, tenderness, fatty acid profile) were analyzed. Groups did not differ in terms of body weight as well as carcass yield and characteristics. There was no difference in meat quality and the fatty acid profile of breast and thigh meat of guinea fowl from TM and CM groups. The findings of this study suggest that both commercial diets (for broiler chickens and turkeys) can be used in meat-type guinea fowl rearing. Due to the lower price of diets fed to the CM group and the lack of significant variation in meat quality traits, its use seems to be more justified from an economic point of view.

Poultry can be exposed to different kinds of immunosuppressive agents that impair health and welfare by destroying innate and acquired immunity leading to diminished genetic potential of poultry for efficient production. Immunosuppression is a condition characterised by humoral and cellular immune dysfunction that leads to increased susceptibility to secondary infections and vaccine failure. Immune dysfunction at the humoral level is largely due to change in soluble factors mediated by complement or chemokines for innate immunity or due to alterations in antibodies or cytokines for adaptive immunity. In contrast, immune dysfunctions at cellular levels include alterations in neutrophils, monocyte/macrophage, and natural killer cells for innate immunity or changes in B or T lymphocytes for adaptive immunity. In poultry, stressinduced immunosuppression is manifested by failure in vaccination, and increased morbidity and mortality of flocks. Immunosuppressive agents can have cytolytic effects on lymphocyte populations leading to atrophied and depleted lymphoid organs. Immunosuppression can be due to infectious agents or noninfectious agents or due to a combination of them. At present, several modern cellular and molecular approaches are being used to determine the status of the immune system during stress and disease. Comprehensive methodologies for the evaluation of immunosuppression by combined non-infectious and infectious aetiologies have not found general application. Currently, investigations are being developed in order to detect genetic expression of immunologic mediators and receptors by microarray technology. It is likely that this new technique will initiate the development of new strategies for the control and prevention of immunosuppression in poultry. A long term immunosuppression preventive approach involves genetic selection for resistance to immunosuppressive diseases.