Effect of energy and protein supplementation on growth and nutrient requirement estimation in crossbred bull calf

Abstract

This study was carried out to investigate the effects of supplying different levels of energy and protein on the growth performance and nutrient requirements estimation in crossbred bull calves. Feeding trial was conducted for 60 days with 12 numbers of crossbred bull calves. The animals were divided into four groups i.e. T0, T1, T2and T3. Four levels of metabolizable energy (ME) and digestible crude protein (DCP) were supplied respectively in four dietary groups, T0=17.4 MJ/d and 85 g/d as maintenance ration, T1=19.22 MJ/d and 188 g/d for 200 g/d targeted BWG, T2=21.29 MJ/d and 243 g/d for 400g/d targeted BWG, T3=23.37 MJ/d and 255 g/d for 600g/d targeted BWG. A positively correlation of BWG with uptake of nutrients (energy and protein) and feed conversion efficiency of different dietary groups was observed. Results revealed that the average daily body weight gain (BWG) in T1 (200 g/d) fulfills against the targeted BWG 200 g/d, T2 maintaining BWG 327 g/d against the targeted BWG 400 g/d and T3 maintaining BWG 422 g/d against the targeted BWG 600 g/d. Considering the growth response of crossbred bull calves it is evident that T1 is better than other dietary groups. Again, estimated ME requirement for maintenance was 16.14 MJ/d and for each kg BWG/d requires ME was 14.69 MJ for 100 kg body weight of crossbred bull calves. The maintenance requirement of DCP was 60.65 g/d and for each kg BWG/d requires DCP was 0.56 g for 100 kg body weight of crossbred bull calves.Bang. J. Anim. Sci. 2017. 46 (3): 179-187

Growth and Feed Conversion Efficiency as Influenced by High Plane of Nutrition in Crossbred Heifers

“…Present findings go with Barua et al (2008) who reported significant (P<0.05) boost in feed conversion efficiency among the dietary groups supplementing higher level of protein that was @ 15, 20 and 25 % CP over the control group. Similarly, Akhter et al (2017) reported improved dry matter conversion efficiency (58.53 to 10.00), protein conversion efficiency (4.39 to 0.92) and energetic efficiency (404.65 to 65.91 MJ MEI/kg body weight gain) on feeing nutrient dens (protein and energy) diet in crossbred (Indigenous x 50% Holstein Friesian) bull calves. In contrary to modern research, Previous works of Umunna et al (1980) revealed that increase in protein levels after a certain level declined the feed conversion and Greathouse et al (1974) reported higher rate of feed conversion due to rising of protein level without concurrent rising of energy value of diet.…”

“…These findings correlate with Barua et al (2008) who reported higher dry matter and nutrient intake with high levels of protein in Red Chittagong heifers. Similarly Akhter et al (2017) reported improvement in intake of crude protein, digestible crude protein and energy intake of crossbred (Indigenous x 50% Holstein Friesian) bull calves on feeding dense (protein and energy) diet whereas dry matter intake was without effect. Zhang et al (2017) reported similar value of dry matter intake (6.3 kg/day) of Holstein heifers on feeding isocaloric diet with low, medium and high protein diet (10.2, 11.9, and 13.5%, respectively) and difference amongst treatments were non-significant due to restricted feeding.…”

“…This growth rate was higher than growth rate (471.76 g/d) reported during last three year (2016, 2017 and 2018) at same experimental farm (Anonymous, 2019) where crossbred calves were fed in group. Akhter et al (2017) reported linear improvement in growth rate (0.043 to 0.422 kg/d), and heart girth (0.06 to 0.18 cm/d), with increase in diet density (protein and energy) of crossbred (Indigenous x 50% Holstein Friesian) bull calves whereas improvement in body length and wither height were non-significant. Similarly, Gardner et al (1988) reported that Holstein heifers fed higher energy during early growth reached breeding size (340 kg) earlier than heifers fed a higher forage to grain ratio (11.3 vs. 12.8 mo of age) and higher (p<.001) daily gains from birth to 340 kg (0.89 vs. o.78 kg).…”