RESUMO
The objective of the present study was to evaluate the association between rainfall and the disappearance of mineral mixtures in the supplementation of cattle on pasture. Supplement consumption and rainfall data were obtained from five experiments carried out between 2016 and 2022. The experiments lasted from 84 to 126 days and had 12 to 18 paddocks formed by Brachiaria spp. under grazing by beef cattle (n = 544), receiving mineral supplementation. Supplement disappearance (SD), difference between the amount offered and leftovers (considering intake and losses) and precipitation (PR), was measured over periods of 14 to 21 days. The periods (n = 565) were classified as very dry, dry, normal, rainy, and very rainy, using the Quantis method. The number of rainy days (RD) and the average precipitation per RD (APRD) per period and the average body weight (BW) of the animals in the periods were also determined. Linear regression analyses assessed the association between BW, PR, RD, and APRD. The average PR in the periods studied was 68.5 mm, ranging from 0.00 to 160.3 mm. Each period had up to six RD, with up to 129.5 mm precipitated. The average BW was 270 kg, ranging from 208 to 335 kg and the average SD was 82.2 g/animal/day, ranging from 0.52 to 176.7 g/animal/day. Differences in RD and APRD are consistent across precipitation classes. In the regression analysis, the model with the highest coefficient of determination was the one that contained the linear and quadratic terms for the RD variable. Including linear and quadratic terms of all variables in a multiple regression represented more than half of the variation in the disappearance of the supplement (R2 = 0.5823). There is no clear relationship between the intensity of precipitation, reflected in the form of classes, and the disappearance of supplements offered to cattle on pasture since dry and very rainy periods can be equivalent. However, variables that characterize the precipitation pattern are more relevant than animal live weight to explain existing variations in supplement disappearance. Among them, the frequency with which precipitation occurs (number of rainy days in the period) seems to be more important than the precipitation rate itself, probably because it is related to the volume of precipitation accumulated in the period.
Assuntos
Brachiaria , Minerais , Bovinos , Animais , Suplementos Nutricionais , ChuvaRESUMO
The aim was to evaluate the animal response and the chemical and physical changes of free-choice mineral mixtures fed to grazing cattle. Growing beef cattle were fed either powder (POW) or agglomerated (AGL) mineral mixtures in three different experiments (Exp.), carried out in pastures of Brachiaria grass. In Exp. 1 and 2, the mineral mixtures were disposed in unsheltered troughs (POWun vs. AGLun), being delivered once (D0, Exp.1) or twice (D0 and D8, Exp. 2), throughout 14-day periods. In Exp. 3, POWun and AGLun were additionally compared to POW in sheltered troughs (POWshe), and the mineral mixtures were disposed in D0, throughout 21-day periods. Non-consumed supplement was removed and sampled on D14 (Exp. 1 and 2) or D21 (Exp. 3). Evaluations included average daily body weight gain (ADG), daily disappearance of the supplement (DSD), penetration force of the supplement mass, faecal chemical composition and serum levels of Ca, P and Mg. In Exp. 1, no effects were observed on ADG and faecal mineral concentrations, however, changes in mineral concentrations and a 40% reduction in Na concentration in the supplement were observed, compared to the initial concentration. AGLun had a lower penetration force. In Exp. 2, there were no effects on DSD and faecal mineral concentrations. POWun showed a smaller reduction in Na content compared to AGLun, and AGLun showed lower penetration force. In Exp. 3, the treatments did not affect ADG, but there was a trend towards higher DSD and serum phosphorus (P) concentration for AGLun (p = 0.08). Higher faecal Na concentration was observed for AGLun and higher Na concentration occurred in non-consumed mixture of POWshe. Mineral supplements offered in uncovered troughs showed altered chemical and physical characteristics, with possible effects on supplement intake. However, the general changes are unlikely to alter animal performance.
Assuntos
Ração Animal , Dieta , Bovinos , Animais , Pós , Dieta/veterinária , Ração Animal/análise , Minerais , Suplementos Nutricionais , Aumento de PesoRESUMO
The economic viability of production of 100 weaned calves aged from 6 to 7 months was estimated at five different production strategy for animals to sales with 360, 400 and 480 kg live animal weight. The best production strategy was used to assess the economic indicators. It was found that with increase in the number of animals in production occurred at the reduced share of operating cost effective - Economic Committee on Revenue. The total costs compared to revenue production for 100-150 animals were 105.74% and 88.26%. The balance of the project was achieved with production of between 110-121 animals. Gross margin, net margin was positive in herds 100-150. It was observed that when the fixed cost is discounted return on capital invested in land, the profit was obtained with the production of 121 animals. The profitability of the project without considering the return on capital invested in land was negative for production of 100 and 110 animals, and positive for the production of 121, 133 and 150 animals. When considering the fixed cost of the system to return on capital invested in land, the enterprise has obtained profits from the production of 133 animals. The profit was R $ 4,951.70 and profitability of 1.93%. The balance in this condition was 1968.49 kilos of meat. For the production of 150 animals profitability was R $ 16,304.54, with a return of 6.37%. Keywords: Econo
A viabilidade econômica da produção de 100 bezerros desmamados com idade de 6 a 7 meses foi estimada em cinco diferentes estratégia de produção para obter animais para vendas com 360, 400 e 480 kg peso animal vivo. A melhor estratégia de produção foi utilizada para avaliar os indicadores econômicos. Verificou-se que com aumento do numero de animais na produção, ocorreu à redução da participação do custo operacional efetivo COE nas receitas. Os custos totais em relação às receitas para produção de 100 a 150 animais, foram de 105,74% a 88,26%. O ponto de equilíbrio do empreendimento foi obtido com produção compreendida entre 110 a 121 animais. Margem bruta, margem liquida foram positivas nos rebanhos de 100 a 150. Observou-se que quando é desconsiderada do custo fixo a remuneração do capital investido em terra, o lucro foi obtido com a produção de 121 animais. A rentabilidade do empreendimento sem considerar a remuneração do capital investido em terra foi negativa para produção de 100 e 110 animais, e positiva para a produção de 121, 133 e 150 animais. Quando se considerou no custo fixo do sistema a remuneração do capital investido em terra, o empreendimento obteve lucro com a produção de 133 animais. A lucratividade foi de R$ 4.951,70 e rentabilidade de 1,93%. O ponto de equilíbrio nesta condição foi de 1968,49 arrobas de carnes. Para a produção de 150 animais a lucratividade