摘要
An experiment was conducted to evaluate the growth performance and cost per gain of indigenous and crossbred （local x Holstein Friesian （L x HF）） bulls under four different improved feed treatments to determine the appropriate ration for economic organic beef production in Bangladesh. Twenty indigenous bulls （average body weight 208.08 ± 13.98 kg） and 20 crossbred （L x l-IF） bulls （average body weight 256.26 ± 26.85 kg） of 24 months age were divided into four equal groups and fed on four diets （T0, T1, T2 and T3） up to 120 d, where To referred to the conventional diet, and T1, T2 and T3 referred as improved organic diets. Required dry matter for individual animal was supplied by roughage and concentrate sources of the ration in the ratio of 2：1. Local grass and paddy straw were supplied to group T0 and T1, Napier grass and straw to group T2, and Napier grass （Pennisetum purpureum）, straw and Ipil-ipil leaf （Leuceana leucucephala） to group Ts as roughage; whereas, the concentrate was supplied as 1.5% of live weight. The results revealed that total dry matter intake （DMI）, total DMI as percent live weight （%LW）, feed conversion ratio （FCR） and average daily gain （ADG） varied significantly （P 〈 0.01） among different treatment groups. Breed also had significant （P 〈 0.01） effect on total DMI, FCR and ADG, but total DMI （%LW） was not affected by breed type. Feed cost expressed as per kg live weight gain （LWG） （BDT/kg LWG; 1USD = 78.95 BDT）, were also affected （P 〈 0.01） by feed treatments and breed type. Indigenous and crossbred bulls fed diet T3 had higher ADG （0.49 kg and 1.17 kg, respectively） and comparatively lower feed costs （156 BDT/kg LWG and 96.78 BDT/kg LWG, respectively）. But crossbred （L × HF） bulls showed the highest ADG （1.17 kg） and the lowest feed cost （96.78 BDT/kg LWG）. Therefore, considering the growth performance and cost per kg gain of the experimental animals, it may be concluded that the crossbred （Lx HF） bulls treated with T3 diet may be used for economic organic beef production in Bangladesh.
作者简介
Nathu Ram Sarker, Ph.D., research fields： animal nutrition and feeds and forage technology.
