Effect of mineral-energy supplementation on the performance of young bulls from different genetic groups on pasture (original) (raw)
Related papers
Revista Brasileira de Zootecnia, 2012
The objective of this study was to estimate requirements of energy, protein and macrominerals of young Nellore/Holstein crossbreds bulls supplemented on pastures of Brachiaria decumbens Stapf. Thirty-five young bulls, at 8.53±0.18 months of age and with initial body weight of 230.6±6.1 kg were used. Ten animals were slaughtered as reference, in different weight range, and the other animals were slaughtered at the end of the experimental period. For estimate of net energy requirements for weight, a regression equation between log of retained energy (RE) and log of empty body weight gain (EBWG) was constructed. Net requirements of Ca, P, Mg, Na and K were determined by the equation Y' = a.b.X b-1 , in which a and b represent the intercept and the coefficient of equation of prediction of macrominerals in body content, respectively.
Effect of different level of energy on growth performance of crossbred bull calves
2016
An experiment was conducted to determine the effects of different levels of energy on growth performance of crossbred (Indigenous × Holstein Friesian) bull calves. Feeding trial was conducted for sixty days long with twelve numbers of crossbred bull calves having almost similar body weight (115±5 kg) and age (1 year and 9 months). The parameters of energy requirements for crossbred bull calves were feed intake (DM), nutrient intake, changes in body weight, daily live weight changes, feed conversion efficiency, coefficient of digestibility of different nutrients, nutritive value and requirements of energy for maintenance and growth. Four levels of dietary energy (T 0, T 1, T 2 and T 3) were supplied to the experimental animals for this purpose. The level of ME was T 0 = 17.4 MJ/d as maintenance ration, T 1 = 20.22 MJ/d for 200 g/d targeted LWG, T 2 = 23.37 MJ/d for 400 g/d targeted LWG, T 3 = 27.29 MJ/d for 600 g/d targeted LWG. It was found that the average daily live weight gain in T 1 (290 g) fulfills against the targeted live weight gain (200 g/d). On the other hand, the expected live weight gain for T 2 and T 3 (400 g/ d and 600 g/d) were not fulfill at the end of experiment. The energy requirement for 100 kg body weight of crossbred bull calves was 17.4 MJ d-1 as maintenance and 15.44 MJ d-1 required for growth of 200g/ d.
Energy and protein requirements for Angus and Nellore young bulls
Livestock Science, 2017
Thirty-two animals with initial body weight (BW) of 380±5.2 kg were used to determine energy and protein requirements of Nellore and Angus young bulls using the comparative slaughter technique. Four animals per breed were slaughtered at beginning of the experiment. The remainder were housed in individual stalls, where eight animals per breed were fed ad libitum a silage/concentrate (SC) diet (300 g/kg of silage and 700 g/kg of a concentrate based on corn and soybean meal, DM basis). Another 4 animals per breed were fed the SC diet at 55% of their dry matter intake adjusted for the metabolic BW of animals that received the SC 2 diet ad libitum. Intake was measured daily and a metabolism trial was conducted with total collection of feces and urine. The data were used then to estimate the metabolizable energy intake. After 84 d of growth the cattle were slaughtered. The data were analyzed using the GLM and NLIN procedures of SAS adopting significance level of 0.05. The metabolizable energy requirements for maintenance differed between Angus and Nellore: 0.580 versus 0.456 MJ/kg BW 0.75 •d-1 when calculated by logarithm model and 0.559 versus 0.483 MJ/kg BW 0.75 •d-1 when calculated by nonlinear model. There was no difference between breeds in the nutritional requirements for growth. Our results support that Zebu bulls have lower net energy requirements for maintenance than Bos taurus taurus bulls.
Animal Production Science
Context Energy supplementation with highly fermentable carbohydrates can be a strategy to maximise the efficiency of nitrogen use (ENU) from high-nutritional value forages. Aims The study aimed to investigate the independent or associated effects of two diurnal feeding times (0900 or 1700 hours) with two sources of energy supplementation (corn or citrus pulp) in the growing of F1 Angus × Nellore young bulls on palisade grass pastures, and their implications on the forage chemical composition, nutrient intake and digestibility, ENU, microbial protein synthesis, animal performance, and gain per area. Methods There were 36 bulls used as experimental animals, with initial bodyweight (BW) of 290 ± 5 kg, and 32 similar bulls were used in a put-and-take system to maintain sward characteristics. The experiment was conducted in a complete randomised design with four treatments and three replications (paddocks). The treatments consisted of energy supplementation at 0.3% BW with corn or citrus...
Energy requirement for maintenance and growth of Nellore bulls and steers fed high-forage diets
Journal of animal science, 2002
Data from three comparative slaughter experiments with individually fed Nellore bulls (n = 31) and steers (n = 66) were utilized to determine their NEm and NEg requirements when fed high-forage diets. The experimental design provided ranges in ME intake, BW, and ADG for the development of regression equations to predict NEm and NEg requirements. The Nellore bulls (Trial 1) were divided into two intake levels (ad libitum and 65% of the ad libitum). The steers (Trials 2 and 3) were allocated to three intake levels (ad libitum and 55 and 70% of the ad libitum). In both trials, there were three slaughter groups within each intake level. The three end points for the bulls were different days on treatment (100, 150, and 190 d and 130, 180, and 200 d, respectively, for older and younger animal subgroups). The steers were slaughtered when animals of the ad libitum treatment reached 400, 440, and 480 kg shrunk BW (SBW) on average for the first, second, and third group, respectively. For all ...
Journal of Animal Science, 2007
for providing the financial support. ABSTRACT: A comparative slaughter trial was conducted with 36 F1 Nellore x Red Angus calves (12 steers, 12 bulls, and 12 heifers), averaging 274 kg BW, to assess the net requirements of protein and energy for growth and maintenance. Three animals from each gender were slaughtered at the beginning of the trial to determine the initial body composition. The remaining calves were randomly assigned to 3 treatments: maintenance level (diet containing 70% of DM as corn silage fed at 1.2% of BW daily) or fed concentrate at 0.75 or 1.5% of BW daily with corn silage available for ad libitum consumption. The diets were isonitrogenous (2% N, DM basis). The experimental design provided ranges in ME intake, BW, and ADG for the development of regression equations to predict the maintenance requirements for NE and net protein (MRNE and MRNP, respectively) and the growth requirement for NE and net protein (GRNE and Page 1 of 39 Journal of Animal Science GRNP, respectively). After 84 d of growth, cattle were slaughtered. The cleaned gastrointestinal tracts, organs, carcasses, heads, hides, tails, feet, blood, and tissues were weighed to measure empty BW (EBW). These parts were ground separately and sub-sampled for chemical analyses. 26 For each animal within a period, DMI was measured daily and samples of feces were collected to 27 determine diet digestibility. There were no differences in MRNE (P = 0.06) among genders. The combined data indicated a MRNE of 71.2 kcal•kg-0.75 of EBW•d-1 , with a partial efficiency of use of ME to NE for maintenance of 0.71. The partial efficiency of use of ME to NE for growth was 0.54 for bulls, 0.47 for steers, and 0.54 for heifers. The GRNE for steers and heifers were similar (P = 0.15) but were 18.7% greater (P = 0.03) for steers and heifers than for bulls. The MRNP did not differ among genders and averaged 2.53 g CP•kg-0.75 of EBW•d-1. Likewise, GRNP was not different among genders. The percentage of retained energy deposited as protein (RE p) increased as the content of retained energy in the gain (RE c , Mcal/kg of empty body gain) decreased. The RE p equation of the pooled data was 46.5 × e-0.2463×REc. We conclude that the energy requirement 36 of crossbred Bos indicus x Bos taurus for maintenance might be less than that of pure Bos taurus 37 and that RE p is nonlinearly, negatively correlated with RE c. The GRNE was less for bulls than for steers and heifers. However, we found no differences in MRNE, MRNP, and GRNP for bulls, steers, and heifers of Nellore x Red Angus crossbreds.
2016
An experiment was conducted to determine the effects of different levels of energy on growth performance of crossbred (Indigenous × Holstein Friesian) bull calves. Feeding trial was conducted for sixty days long with twelve numbers of crossbred bull calves having almost similar body weight (115±5 kg) and age (1 year and 9 months). The parameters of energy requirements for crossbred bull calves were feed intake (DM), nutrient intake, changes in body weight, daily live weight changes, feed conversion efficiency, coefficient of digestibility of different nutrients, nutritive value and requirements of energy for maintenance and growth. Four levels of dietary energy (T 0, T 1, T 2 and T 3) were supplied to the experimental animals for this purpose. The level of ME was T 0 = 17.4 MJ/d as maintenance ration, T 1 = 20.22 MJ/d for 200 g/d targeted LWG, T 2 = 23.37 MJ/d for 400 g/d targeted LWG, T 3 = 27.29 MJ/d for 600 g/d targeted LWG. It was found that the average daily live weight gain in...
Nutritional management of developing bulls
Proceedings of the 2019 Applied Reproductive Strategies in Beef Cattle Conference, 2019
Bull development is a necessary and vital entity of beef production, as bulls account for a substantial portion of the genetic influence in a cow herd, and are the primary means through which the majority of producers affect genetic progress. The utilization of rapid development programs allows for the use of bulls at a younger age, reduces overall production costs, and decreases the down-time prior to implementing genetics within the herd. Breeding bulls are commonly fed high-energy diets in order to meet or exceed the rate of physiological development required to achieve sexual maturity prior to their first breeding season, while simultaneously evaluating genetic merit for growth and other economically-relevant traits. It is commonly thought that post-weaning nutrition has the greatest environmental influence on sexual development in bulls, yet there is compelling evidence to suggest that pre-weaning nutritional management influences these outcomes to a substantial, and possibly even a greater degree. This review will focus on the impact of both pre-and post-weaning plane of nutrition on sire development. While not addressed herein, readers are heavily cautioned to avoid overlooking the importance of mineral nutrition, as mineral deficiencies or toxicities should be expected to influence bull fertility.
Italian Journal of Animal Science, 2008
The aim of this trial was to evaluate the influence of two protein sources and the energy levels of the diet on growth performance and carcass quality of young Marchigiana bulls. Eighteen weaned young bulls (129 d of age) were equally divided into three groups. Until the slaughter weight (620 kg) was achieved two groups were fed diets with the same protein and energy concentrations, but differing in protein sources (faba bean-FB vs soya bean meal s.e.-SB), and the last group was fed high-energy diets (HE) with both protein sources in the concentrates. Body weight, daily weight gain and biological efficiency of growth at different ages and periods, and feed conversion indexes, were calculated from individual growth curves. Beginning at 180 d of age Group HE showed always significantly (P<0.01) higher body weight and daily weight gain than groups FB and SB. Moreover, group HE reached the slaughter weight and conformation earlier than the other two groups (500 vs 540 d, respectively). The protein sources affected the growth only in the first phase after weaning (body weight at 180 d: 173 vs 186 kg for groups FB and SB, respectively; P<0.01). The highest energy diets appreciably improved growing rate, but worsened feed conversion indexes. Animal and carcass measurements were not influenced either by energy intake or by dietary protein source. Group HE showed the lowest incidence of long bones (6.2 vs 6.7 vs 5.8% of cold carcass for FB, SB and HE groups respectively; P<0.01) and the highest percentage of fat (5.1 vs 4.7 vs 7.1% of cold carcass, for FB, SB and HE groups respectively; P<0.01). As respects the protein sources, only the incidence of long bones resulted significantly different between FB and SB groups (6.2 vs 6.7% of cold carcass, respectively; P<0.05). These data demonstrate that faba beans could be used as alternative sources to soya bean meal s.e., as it did not influence growth rate and feed conversion indexes in the entire experimental period. Nevertheless, immediately after weaning, the association of faba beans with another protein source richer in rumen undegradable protein would be preferable. Moreover the utilisation of high energy feeding planes could improve the growth dynamics of young Marchigiana bulls, although in the final phase it may be suitable to reduce the energy intake in order to decrease fat deposition.