Manotosh Dhar
Department of Poultry Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
Sachchidananda D. Chowdhury
Department of Poultry Science, Bangladesh Agricultural University, Mymensingh, Bangladesh
Crossbreds, Nutrient density, Grower, Pre-layer, Performance
Animal Health and Management
Nutrition, Chicken
Feed Ingredients: Feed ingredients such as wheat (Tritioum aestisum), maize (Zea mays), broken rice (Oryza sativa), rice polish, wheat bran, soybean meal (Glysine max), mustard oil cake (Brassica spp), full-fat soybean and meat and bone meal were collected from feed seller, spent tea leaves from tea stalls and egg shards from bakeries of Mymensingh town. Ipil-ipil leaves were collected from poultry farm and duckweeds from ponds of Bangladesh Agricultural University campus. Ipil-ipil leaves, duckweeds and spent tea leaves were sun-dried and egg shards were boiled, sun-dried and ground and then all the feed ingredients were stored in plastic containers before chemical analyses and inclusion in the diet. Chemical Analyses of the Feed Ingredients: Proximate analyses of feed ingredients were done for CP, EE, CF, NFE and TA following the principles (AOAC, 2000). Calcium (Ca) and total phosphorus concentrations were done following the methods of Jackson (1973) and AOAC (2000). Determination of starch was in accordance with the method of Kent-Jones and Amos (1967) and sugar contents were measured in accordance with the method of Hall and Hacskaylo (1963). Estimation of Nutrient Requirement for Experimental Birds: “Sonali” is a crossbred (RIR male x Fayoumi female) dual-purpose chicken. An intensive literature search revealed no nutrient specification for this crossbred chicken. So, nutrient requirements were estimated from the recommendations of di#erent nutrient specifications for layer-type birds as shown (Bolton and Blair, 1977; Blair, et al., 1983; Bangladesh Standard Testing Institute, 1988; Singh and Panda, 1992, ; National Research Council,1994.). Based on these background information, the nutrient requirements of grower chickens were estimated as means of the values recommended in five specifications by compromising the minimum and maximum values. Experimental Birds and Diets: One hundred twenty-six 8-week-old F1 crossbred (Rhode Island Red male x Fayoumi female) chickens were procured for the study. They were fed three grower diets up to 20 weeks of age. At 20 weeks of age, ninety birds on grower diets were switched over to pre-layer diet by discarding the exceptionally underweight and overweight birds and reared up to 22 weeks of age. The chickens were equally and randomly distributed to receive three dietary treatments having three replications each viz. LND (14% CP and 2550 kcal ME/kg), MND (15% CP and 2750 kcal ME/kg) and HND (16% CP and 2950 kcal ME/kg). Management: The birds were reared on sawdust-littered floors and they were allowed to scavenge in the poultry farmyards (226 m2, for grower birds and 528 m2, for pre-layer birds) for 0 hours daily except during the adverse environmental conditions when they were totally confined. Mixed green grasses, grits, insects and earthworms were available for scavenging birds in the farmyards. The birds were vaccinated against Newcastle Disease, Fowl Pox and Fowl Cholera as a routine programme. Uniformity: Flock uniformity was calculated by weighing the birds, calculating the average body weight, determining the limits 10% above and below the average and finally calculating the percentage of birds whose body weight was within those limits. Record Keeping and Data Processing: Bodyweight, feed consumption, uniformity, age at sexual maturity, bodyweight at first egg and mortality were recorded and necessary calculations were made for weight gain, FCR, flock uniformity and survivability. Data collected from feeding trials were statistically analyzed following the principles of a completely randomized design (Steel and Torrie, 1980). General linear model procedure was employed according to SAS statistical package (SAS, 1988) to detect significant e#ect, due to diet. Differences between mean values were identified by least significant difference (LSD).
The Journal of Poultry Science, 44: 42-51, 2007
Journal