RESUMO
The aim of this study was to evaluate the effect of inclusion of two acidifiers blend (with different protection levels) on the acidification potential in vitro, apparent total tract digestibility of diet nutrients, blood metabolites, and average daily gain of nursery piglets. Two commercial acidifiers blend additives (AC1 and AC2) were evaluated. The acidification potential of the two acidifiers blend added to the diet were tested by buffering capacity and initial pH in vitro. For the evaluation of apparent digestibility of diet nutrients, blood metabolites and average daily gain, two experiments were carried out. The AC2 acidifier had a greater effect on the initial reduction in pH and a lower linear buffering rate of the diet. The use of acidifiers did not improve the nutrient digestibility of the diets and had no effect on the blood metabolite concentrations of urea, total protein, albumin, globulin, and lactate. Although the inclusion of acidifiers in the diets did not affect the apparent total tract digestibility of the diet nutrients the inclusion of the AC2 acidifier at different levels showed a negative quadratic effect on the average daily gain, with the best inclusion level being 0.26%.
O objetivo deste estudo foi avaliar o efeito da inclusão de dois acidificantes (com diferentes níveis de proteção) sobre o potencial de acidificação in vitro, a digestibilidade aparente do trato total dos nutrientes da dieta, os metabólitos sanguíneos e o ganho médio diário de leitões. Foram avaliados dois acidificantes comerciais (AC1 e AC2). O potencial de acidificação dos acidificantes adicionados às dietas foi testado quanto à capacidade tamponante e ao pH inicial in vitro. Para avaliação da digestibilidade aparente dos nutrientes da dieta, dos metabólitos sanguíneos e do ganho médio diário, foram realizados dois experimentos. O acidificante AC2 teve maior efeito na redução inicial do pH e menor taxa linear de tamponamento linear da dieta. O uso de acidificantes não melhorou a digestibilidade dos nutrientes das dietas e não teve efeito sobre as concentrações dos metabólitos sanguíneos de ureia, proteína total, albumina, globulina e lactato. Embora a inclusão de acidificantes nas dietas não tenha afetado a digestibilidade aparente do trato total dos nutrientes da dieta, a inclusão do acidificante AC2 em diferentes níveis apresentou efeito quadrático negativo no ganho médio diário, com o melhor nível de inclusão sendo 0,26%.
Assuntos
Animais , Sus scrofa , Dieta/veterinária , Ácidos Orgânicos , Fixadores , Soluções TampãoRESUMO
A relação da eficiência nutricional com a idade e o peso à puberdade e as características reprodutivas foram estudadas em 35 novilhas F1 Holandês x Gir, em ensaios usando o consumo alimentar residual (CAR) nos períodos pós-desaleitamento (PD) e pós-puberdade (PP). Novilhas PD (P<0,0001) e PP (P<0,001) foram ranqueadas como de alta, intermediária e baixa eficiências e apresentaram CAR de -0,259 -0,014 e 0,346kg/dia e -0,848 -0,096 e 0,842kg/dia, respectivamente. Novilhas PD diferiram (P<0,05) na idade à puberdade entre ranques de alta, intermediária e baixa eficiências, em média, aos 339,7; 346,4; 315,3 dias, respectivamente. Os pesos à puberdade de novilhas PD com alta, intermediária e baixa eficiências foram, em média, de 321±28,1kg e não diferiram (P>0,05) entre CAR. Não foi verificada correlação entre diâmetro folicular, taxa de crescimento do folículo, número de ondas foliculares no ciclo estral e taxa de gestação à primeira IA com o CARPD ou CARPP. Novilhas F1HG selecionadas para CAR com baixa eficiência podem ter idade à puberdade 10 dias a mais, quando comparadas às novilhas de alta eficiência para CAR. Não foi verificado que novilhas selecionadas para alta ou baixa eficiências alimentares, usando CAR, tivessem algum impacto negativo sobre características reprodutivas avaliadas.(AU)
The relationship between nutritional efficiency and age and weight at puberty and reproductive traits was studied in 35 F1 Holstein x Gyr heifers, in trials using residual food consumption (CAR) in the post-weaning (PW) and post-pubertal (PP) periods. PD heifers (P<0.0001) and PP (P<0.001) were classified as high, intermediate and low efficiencies and presented CAR of -0.259 -0.014 and 0.346kg/day and -0.848 -0.096 and 0.842kg/day, respectively. PD heifers differed (P<0.05) in age at puberty between high, intermediate and low efficiencies, on average, at 339.7, 346.4 and 315.3 days, respectively. The weight at puberty of PD heifers with high, intermediate and low efficiencies were, on average, 321±28.1kg and did not differ (P>0.05) between CAR. No correlation was found between follicular diameter, follicle growth rate, number of follicular waves in the estrous cycle and pregnancy rate at 1st AI with the CARPD or CARPP. F1HG heifers selected for CAR with low efficiency can be aged at puberty 10 days longer when compared to high-efficiency heifers for CAR. These results did not show that heifers selected for high or low food efficiency, using CAR, had negative impact on the reproductive characteristics evaluated.(AU)
Assuntos
Animais , Feminino , Bovinos , Fenótipo , Aumento de Peso , Ciclo Estral , Comportamento Alimentar , Pesos e Medidas Corporais/veterinária , Taxa de GravidezRESUMO
A relação da eficiência nutricional com a idade e o peso à puberdade e as características reprodutivas foram estudadas em 35 novilhas F1 Holandês x Gir, em ensaios usando o consumo alimentar residual (CAR) nos períodos pós-desaleitamento (PD) e pós-puberdade (PP). Novilhas PD (P<0,0001) e PP (P<0,001) foram ranqueadas como de alta, intermediária e baixa eficiências e apresentaram CAR de -0,259 -0,014 e 0,346kg/dia e -0,848 -0,096 e 0,842kg/dia, respectivamente. Novilhas PD diferiram (P<0,05) na idade à puberdade entre ranques de alta, intermediária e baixa eficiências, em média, aos 339,7; 346,4; 315,3 dias, respectivamente. Os pesos à puberdade de novilhas PD com alta, intermediária e baixa eficiências foram, em média, de 321±28,1kg e não diferiram (P>0,05) entre CAR. Não foi verificada correlação entre diâmetro folicular, taxa de crescimento do folículo, número de ondas foliculares no ciclo estral e taxa de gestação à primeira IA com o CARPD ou CARPP. Novilhas F1HG selecionadas para CAR com baixa eficiência podem ter idade à puberdade 10 dias a mais, quando comparadas às novilhas de alta eficiência para CAR. Não foi verificado que novilhas selecionadas para alta ou baixa eficiências alimentares, usando CAR, tivessem algum impacto negativo sobre características reprodutivas avaliadas.(AU)
The relationship between nutritional efficiency and age and weight at puberty and reproductive traits was studied in 35 F1 Holstein x Gyr heifers, in trials using residual food consumption (CAR) in the post-weaning (PW) and post-pubertal (PP) periods. PD heifers (P<0.0001) and PP (P<0.001) were classified as high, intermediate and low efficiencies and presented CAR of -0.259 -0.014 and 0.346kg/day and -0.848 -0.096 and 0.842kg/day, respectively. PD heifers differed (P<0.05) in age at puberty between high, intermediate and low efficiencies, on average, at 339.7, 346.4 and 315.3 days, respectively. The weight at puberty of PD heifers with high, intermediate and low efficiencies were, on average, 321±28.1kg and did not differ (P>0.05) between CAR. No correlation was found between follicular diameter, follicle growth rate, number of follicular waves in the estrous cycle and pregnancy rate at 1st AI with the CARPD or CARPP. F1HG heifers selected for CAR with low efficiency can be aged at puberty 10 days longer when compared to high-efficiency heifers for CAR. These results did not show that heifers selected for high or low food efficiency, using CAR, had negative impact on the reproductive characteristics evaluated.(AU)
Assuntos
Animais , Feminino , Bovinos , Fenótipo , Aumento de Peso , Ciclo Estral , Comportamento Alimentar , Pesos e Medidas Corporais/veterinária , Taxa de GravidezRESUMO
The aim of this study was to evaluate the effects of increasing the total solids (TS) content of liquid feed, by adding increasing amounts of milk replacer powder to whole milk, on age at puberty and postweaning performance, glucose metabolism, and mammary fat pad of dairy heifers. Crossbreed Holstein × Gyr heifers (n = 58) were distributed into 4 different treatments during the preweaning period. Treatments consisted of liquid feeds with TS content of 12.5 (actual TS = 13.5 ± 0.53%; n = 15), 15.0 (actual TS = 16.1 ± 0.03%; n = 15), 17.5 (actual TS = 18.2 ± 0.14%; n = 13), or 20.0% (actual TS = 20.4 ± 0.24%; n = 15), which were provided up to 59 d old. From 60 to 89 d old, the animals received the same starter offered during the preweaning period in addition to corn silage ad libitum starting at 70 d old. From 90 to 104 d old, the animals were adapted to a total mixed ration. At 105 d old, the animals were distributed in 4 paddocks equipped with electronic feed and water bins and were fed the same total mixed ration ad libitum. A period of adaptation to the electronic feed bins occurred from 105 to 119 d old. Feed and water intake and body weight and body frame development were assessed until puberty. Mammary gland evaluations were performed monthly by ultrasonography from 120 d of age until puberty onset. Puberty onset was determined as plasma progesterone concentration greater than 1 ng/mL in 2 consecutive samples collected 7 d apart. The date of puberty onset was recorded as the collection day of the first of these samples. A glucose tolerance test was performed at 280 d of age. The increased TS content of the liquid feed fed during the preweaning period did not affect dry matter intake, performance, age at puberty, glucose metabolism, or mammary gland fat pad at later stages of rearing process. Conversely, hip width and heart girth increased linearly up to 150 and 240 d of age, respectively, as a result of the increased TS concentration of the liquid feed during the preweaning period.