RESUMO

O objetivo deste trabalho foi estudar o perfil oxidativo de concentrados para bovinos adicionados de óleo de soja, refinado e degomado, em um período de armazenamento de 15 dias, sob as temperaturas de 25ºC e 40ºC. Foram formados cinco grupos de alimentos: controle (C) sem adição de óleo, tratamentos (T) 1, 2, 3 e 4 com adição de 2, 4, 6 e 8%, respectivamente, de óleo de soja refinado ou degomado. Para tal, foram avaliados os índices de peróxidos e de acidez. Com relação à influência da temperatura de estocagem, ao longo do período experimental à 25ºC, não houve alteração com relação aos valores de índice de peróxido quando se adicionou óleo de soja refinado aos concentrados, contudo, à 40ºC, houve aumento observando-se um valor máximo em torno de 0,9 mEq/kg de concentrado. O índice de acidez do óleo refinado extraído dos concentrados armazenados à 25ºC não foi alterado ao longo do período de armazenamento, e à 40ºC resultou em aumento de 19, 25, 44 e 44% para os respectivos T1, T2, T3 e T4 em relação ao controle. Quanto à influência do tipo de óleo processado na oxidação lipídica dos concentrados armazenados à 40ºC, a adição de óleo de soja refinado não alterou os índices de peróxidos dos concentrados ao longo dos 15 dias de experimento, e para o degomado observou-se um aumento no 3º dia de armazenamento em 57%, 44%, 123% e 93% para os respectivos T1, T2, T3 e T4, em relação ao controle. Também, o efeito da adição de óleo de soja degomado resultou em aumento do índice de acidez de 21%, 36%, 43% e 57% a partir do 5º dia de experimento, em relação ao 1º dia. Conclui-se que durante os 15 dias de armazenamento, houve diferença no perfil oxidativo dos concentrados adicionados de óleo de soja quando se comparou as temperaturas de 25ºC e 40ºC, mas se manteve inalterado quando se avaliou os tipos de óleo refinado e degomado em diferentes porcentagens. Assim, a adição de óleo de soja refinado ou degomado não altera o perfil oxidativo do concentrado para bovino sob as condições deste estudo.

The objective of this work was to study the oxidative profile of concentrates for cattle added soybean oil, refined and degummed in a storage period of 15 days, at temperatures of 25ºC and 40ºC. Were formed five food groups: control (C) without addition of oil, treatments (T) 1, 2, 3 and 4 with the addition of 2, 4, 6 and 8%, respectively, of refined or degummed soybean oil. For this purpose ware available index of peroxide and of acidic. Regarding the influence of storage temperature, the addition of refined soybean oil did not alter the values of the peroxide during the trial period at 25ºC, however, at 40ºC of storage of food alter this parameter and was shown a maximum value about 0.9 mEq/kg of concentrate. The acidity of refined oil extracted from concentrates stored at 25ºC was not changed during the storage period, and 40ºC resulted in an increase of 19, 25, 44 and 44% for the respective T1, T2, T3 and T4 compared the control. Regarding the influence of oil processed in lipid oxidation of concentrates stored at 40ºC, the addition of refined soybean oil did not alter the levels of peroxide concentrates over the 15 days of experiment, and the degummed observed an increase in 3rd day of storage in 57%, 44%, 123% and 93% for the respective T1, T2, T3 and T4, compared to control. Also, the effect of addition of crude soybean oil resulted in increased acid value of 21%, 36%, 43% and 57% from the 5th day of experiment, as compared to day 1. Thus, the addition of refined soybean oil or degummed not change profile for bovine oxidative concentrated under the conditions of this study.

Assuntos

RESUMO

Background: Reproductive efficiency is one of the most important characteristics for beef cattle. Bos indicus cattle have longer periods of postpartum anestrus, which contributes to poorer reproductive efficiency of zebu cows when compared with that of Bos taurus , this facts are particular relevant in primiparous cows. These challenges are more important in primiparous cows in pasture management systems because the intake of nutrients during the postpartum period is not sufficient to meet requirements for growth as well as lactation. The objectives of this study were to evaluate the days postpartum at conception and the pregnancy rate at the end of a 90 days breeding season in primiparous and multiparous cows. Materials, Methods & Results: The study was conducted at the Experimental Farm of the Capim Branco, Federal University of Uberlandia, in the breeding season of 2009/2010. It was used 14 primiparous and 84 multiparous Nelore cows. The females were treated with the following protocol. On Day 0, all cows received an intravaginal device containing 1.9 g progesterone (CIDR®) and 1.0 mg, i.m. of estradiol cypionate (ECP ®). On Day 7 the cows received 12.5 mg, i.m. dinoprost tromethamine (Lutalyse®). On Day 9, the intravaginal devices were removed, and calves were temporally weaned. On Day 11 (48 h after intravaginal device withdrawal), all cows were inseminated and calves reunited with their dams immediately after insemination. All cows that returned to estrus before pregnancy diagnosis were re-inseminated 12 h after estrous detection. Pregnancy diagnosis was performed by transrectal ultrasonography 30 days after TAI, confirmed 60 days after the end of breeding season. The pregnancy rate at end of the breeding season was calculated by dividing the number of pregnant cows heifers by the number of cows used in the breeding season. [...]

Assuntos

RESUMO

Background: Reproductive efficiency is one of the most important characteristics for beef cattle. Bos indicus cattle have longer periods of postpartum anestrus, which contributes to poorer reproductive efficiency of zebu cows when compared with that of Bos taurus , this facts are particular relevant in primiparous cows. These challenges are more important in primiparous cows in pasture management systems because the intake of nutrients during the postpartum period is not sufficient to meet requirements for growth as well as lactation. The objectives of this study were to evaluate the days postpartum at conception and the pregnancy rate at the end of a 90 days breeding season in primiparous and multiparous cows. Materials, Methods & Results: The study was conducted at the Experimental Farm of the Capim Branco, Federal University of Uberlandia, in the breeding season of 2009/2010. It was used 14 primiparous and 84 multiparous Nelore cows. The females were treated with the following protocol. On Day 0, all cows received an intravaginal device containing 1.9 g progesterone (CIDR®) and 1.0 mg, i.m. of estradiol cypionate (ECP ®). On Day 7 the cows received 12.5 mg, i.m. dinoprost tromethamine (Lutalyse®). On Day 9, the intravaginal devices were removed, and calves were temporally weaned. On Day 11 (48 h after intravaginal device withdrawal), all cows were inseminated and calves reunited with their dams immediately after insemination. All cows that returned to estrus before pregnancy diagnosis were re-inseminated 12 h after estrous detection. Pregnancy diagnosis was performed by transrectal ultrasonography 30 days after TAI, confirmed 60 days after the end of breeding season. The pregnancy rate at end of the breeding season was calculated by dividing the number of pregnant cows heifers by the number of cows used in the breeding season. [...](AU)

Assuntos