Md. Rahat Ahmad Redoy
Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
Md. Mahbubur Rahman
Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
Mohammad Al-Mamun
Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
Khan Md. Shaiful Islam
Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
Broiler diet, Citric acid, Free fatty acid, Pepsin digestibility, Peroxide value
Shahjalal Animal Nutrition Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh 2202, Bangladesh
Animal Health and Management
Experiment 1: This study was conducted at Shahjalal Animal Nutrition Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh 2202, Bangladesh from January to April 2020. The experimental procedures, animal handling and the collection of samples were reviewed and approved by the Animal Welfare and Experimental Ethics Committee of Bangladesh Agricultural University, Mymensingh 2202 (AWEEC/BAU/2020/31). Fresh poultry viscera were collected from the local market and a part was kept in room temperature (25-30EC) and another part at chilling temperature (4EC). After that, a certain volume of poultry viscera minced through a 5.0 mm sieve using a meat mincer (TORREY 32, Mexico). Immediately after mincing, different concentrations of citric acid and sulfuric acid (0.5 and 1.0%) were added and stored at room temperature. Experimental groups consisted of the (i) Normal sample (1000 g fresh poultry viscera without preservative at room temperature), (ii) Chilled sample (1000 g fresh poultry viscera without preservative at chilling temperature); (iii) 0.5% Citric acid (5 g citric acid +1000 mL water +1000 g fresh poultry viscera), (iv) 1.0% Citric acid (10gm citric acid + 1000 mL water + 1000 g fresh poultry viscera), (v) 0.5% Sulfuric acid (5 mL H2SO4 +1000 mL water +1000 g fresh poultry viscera) and (vi) 1.0% Sulfuric acid (10 mL H2SO4+1000 mL water+1000 g fresh poultry viscera). Viscera treated with both citric and sulfuric acids (0.5 and 1.0%) were collectively considered as preservative samples. All the samples were kept in glass jars up to 48 h. The pH, peroxide value (POV) and free fatty acids (FFA) of viscera were monitored at 0, 24, 48 h of storage. In contrast, pepsin digestibility and microbial quality were determined at 24 and 48 h of storage. An amount of 5 g viscera was mixed with 45 mL of distilled water and homogenized for 1 min by using a grinder (MG-300HM, Taishan AISON Electronics Co, China). After that, it was centrifuged at 2000×g for 15 min and the pH was measured using a pH meter (HI-2211, Hanna Instruments, USA). To determine peroxide value (POV), 3 g viscera were heated at 60EC for 30 min and 30 mL acetic acid-chloroform solution (3:2, v/v) was used for dissolving fat. The POV was calculated according to the procedure described by Rahman et al.16 and expressed as milliequivalent peroxide per kilogram of the sample (meq kgG1). Free fatty acid (FFA) was determined by mixing 5 g of the homogenized viscera with 30 mL of chloroform, centrifuging in a vortex machine for 1 min. Then, a 1% phenolphthalein indicator was added to the filtrate and titrated against 0.1N alcoholic KOH according to the method described by Rahman et al.16. The pepsin digestibility was determined using 0.2% pepsin (0.2 g of 1:10,000 activity pepsin; Sigma-Aldrich Co., USA) according to the method described by AOAC17. Total viable count (TVC) and total coliform count (TCC) were determined according to the procedure described by Rima et al.18 and expressed as log of colony-forming units per gram (Log CFU gG1). Experiment 2: Fresh viscera were collected from the local market and mixed with 1.0% citric acid immediately as described in the previous experiment. After that, viscera were kept in a hot air oven at 50EC for 24 h, followed by 70EC for 72 h. Then viscera were ground using a locally made grinder fitted with US #20 sieves (850-µm openings). Poultry visceral meal contained 93.1% dry matter and 57.3% crude protein, 37.4% ether extract, 4.7% Ash, 0.85% calcium, 0.86% available phosphorus and 0.04% sulfur on a dry matter basis was ready to be fed. A total of 150 straight run day-old broiler chicks (Cobb 500; initial body weight 46±0.5 g) were distributed in a completely randomized design consisting of three experimental groups with five replications having thirty birds per replicate. The experiment was continued for 28 days. The experimental diets were (I) 5% protein concentrate +0% PVM, (ii) 2.5% protein concentrate +2.50% PVM and (iii) 0% protein concentrate +5.0% PVM. Diets were formulated considering iso-nitrogenous and iso-caloric. Experimental birds were kept in a floor pen (4 cm sawdust bedding) having floor space of 0.91 m2 (120 cm×76 cm) for ten birds. The brooding temperature was maintained at 32EC in 1st week and after that, it gradually decreased by 3EC each week until it reached 21EC. Feed intake (FI) was calculated based on the difference between the offered and residual feed in the feeder at the end of the week. The body weight (BW) of an individual bird was measured weekly and total body weight gain (BWG) was calculated based on the difference between the initial and final body weights. The feed conversion ratio (FCR-kg FI kgG1 LWG) was determined cumulatively through the collected data. The proximate components of feeds and viscera meal were analyzed in triplicate, according to AOAC20. At the end of the feeding trial, five birds from each group were sacrificed to collect blood and carcass samples. Around 5 mL of the blood sample was collected in a sodium-heparinized tube and kept in an icebox until centrifugation. Samples were centrifuged at 6000×g for 15 min for plasma separation and the plasma was stored at -20EC. Plasma glucose, urea nitrogen (BUN) and total protein were analyzed using different enzymatic kits in a bio-analyzer (Urit-810, URIT Medical Electronics Group Co, Ltd, China).
Int. J. Poult. Sci., 20 (2): 67-75, 2021
Journal