Evaluation of antistress and growth promoting effect of aswagandha (Withania somnifera) in broiler chicken

Abstract

The purpose of the study was to asses the antistress and growth promoting effect of Withania somnifera in broiler chicken. Sixty numbers of day old broiler chicks (vencob) procured from a commercial hatchery were reared under standard managemental conditions. At day old they were randomly divided into six groups (G1 to G6) with ten birds in each group. The study was conducted upto sixth week of age. The birds in various groups were as follows, G1- Normal , G2- Normal +5 g W. somnifera per kg feed, G3- Normal + 10 g W. somnifera per kg feed, G4- Stressed, G5- Stressed + 5 g W. somnifera per kg feed, and G6- Stressed + 10 g W. somnifera per kg feed. Production parameters such as body weight, weekly weight gain, feed consumption and feed efficiency were evaluated on weekly basis. All birds were immunized with 1ml of 7 per cent sheep red blood cells intravenously five days before subjecting to stress, for the evaluation of immune status. Stress was induced from four weeks to six weeks of age by reducing the floor space for a bird 1/3rd (372 cm2/ bird) of the optimum requirement (1116 cm2/bird). Blood samples were collected from wing vein, five days and one day before the induction of stress as well on day one, three, six, nine, twelve and fifteen days after the induction of stress. Haematological parameters such as total erythrocyte count (TEC), total leukocyte count (TLC), haemoglobin (Hb), heterophil lymphocyte ratio (H:L), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) and volume of packed red cells (VPRC) were determined. Serum was utilized for analysis of total protein, albumin, globulin, glucose, C-reactive protein (CRP), alanine amino transferase (ALT) and total cholesterol. The A:G was derived. The immunological status was studied by haemagglutinin assay (HA). Tissues from liver were used for estimating tissue lipid peroxidation (LPO) and reduced glutathione (GSH) levels. The mucous membrane of proventriculus and duodenum were used for protease and amylase estimation respectively. The whole pancreas was used for pancreatic lipase estimation. Slaughter weights, carcass weight, giblet weight, weight of organs (spleen, bursa and adrenal) were also studied. The result of the present study revealed that supplementation W. somnifera did not affect the normal growth of broiler chicken. There was not much variation in slaughter weight, carcass weight and weight of organs between W. somnifera supplemented and not supplemented group. In stressed birds supplementation of W. somnifera ameliorated the stress related reduction in organ weight. Supplementation of W. somnifera did not affect the haematological parameters such as Hb, VPRC, TEC, TLC, MCV, MCH, MCHC and H:L in normal birds. Supplementation of W. somnifera to stressed birds reduced the stress induced increased TEC, MCV and H:L in birds. The supplementation of W. somnifera did not affect the serum total protein, albumin, globulin and A:G in normal birds. But in stressed birds the increased total protein was decreased by supplementation of W. somnifera. The supplementation of W. somnifera did not cause a sustained increase in ALT values revealing that it was not hepatotoxic to broilers. Supplementation of W. somnifera to stressed birds reduced the stress related hyperglycemia and hypercholesterolemia. The increased level of C-reactive protein in stressed birds was reduced through supplementation of W. somnifera. Supplementation of W. somnifera increased the GSH and decreased LPO levels in birds. Supplementation of W. somnifera ameliorated the stress related oxidative damage through the reduction of LPO and increase of GSH levels. W. somnifera improved the immune status of normal birds as well as that of immunosuppressed stressed birds. Besides, it also improved the activities of gastrointestinal enzymes in normal and stressed birds.