Effect of enzymes and polyethylene glycol addition to Kalahari melon (Citrullus lanatus)-based diets on egg production performance in layer chicken

Abstract

The research is aimed to improve the nutritional quality of Kalahari melon meal (KM) in layer chicken diets by incorporating external digestive enzymes and polyethylene glycol. Chapter one outlines the study's context, issue at hand, rationale, and its intended goals and purposes. Chapter two presents a comprehensive view of layer chicken farming alongside the nutritional composition and significance of incorporating Kalahari melon in diets for chickens. It also provides a summary of the voids and contradictions discovered in the research and provides a comprehensive overview of poultry diets that contain exogenous feed enzymes. Chapters three, four and five studied the effect of polyethylene glycol and protease enzyme on FI, body weight changes, haematology and serum biochemistry, egg production parameters (internal and external), fatty acid profile, internal organs, and bone development. Five dietary treatments were formulated by including 10% KM, polyethylene glycol and protease enzyme in poultry diets. The following diet plans were developed: Control (commercial layer feed), 10%KM (10 %KM diet), PRO (10% KM diet + protease enzyme), PEG (10% KM diet + polyethylene glycol), KMEP (10% KM diet + protease enzyme + polyethylene glycol). A total of 150- leghorn layer hens at 18 weeks old were purchased for use in the research. The hens were distributed randomly among 5 different dietary plans using a completely randomized arrangement. Each of these plans consisted of 10 separate cages, with each cage housing 3 birds, serving as the experimental unit. Diets significantly affected (P< 0.05) average daily gain, average weekly feed intake, average daily feed intake and feed to egg ratio. The 10% Km diet had the high values for all parameters except for feed to egg ratio. The peg diet had the highest value for feed to egg ratio (31.59±2.16). The observation made on serum biochemical and haematological had no linear or quadratic responses (P >0.05). In comparison to other diets, the control diet exhibited elevated levels of lymphocytes, eosinophils, basophils, and red iii blood cells. The KM containing diets had high values(P>0.05) for all parameters in serum biochemistry except for blood urea nitrogen and ALKP. With regards to egg production indices (chapter 4), diet had no influence (P>0.05) on all egg production indices apart from the NFEI (P<0.05), with the highest value in PRO diet followed by the KMEP diet. With all other parameters, the KM containing diets, whether with feed additives or not appeared to have better performances compared to the control diet while the PEG diet seemed to supress the performance of hens. Of all the diets containing KM oil cake, while the values of hens fed the PEG diet had similar performance as the control. The birds on the PRO diet experienced fewer cracked eggs in comparison to those on the KMEP and control diets. All egg external quality parameters, with the exception of the eggshell ratio, eggshell obtuse, breaking strength, and egg breadth, were unaffected by diet. The values for egg width and shell breaking strength (Shell BS) were highest (P < 0.05) in the commercial diet (Con), with the chickens fed the 10% KM diet following closely behind. The yolk index, haugh unit, albumen weight, and albumen ratio were the only internal parameters that were not influenced by diet. The hens fed the 10%KM diet had the highest (P < 0.05) yolk height (YH) and yolk weight (YWT).