Potencial leiteiro de animais da raça Pantaneira na região do Alto Pantanal do Mato Grosso do Sul / Dairy potential of pantaneira breed upper region of pantanal of Mato Grosso Sul

The Pantaneira breed is in danger of extinction. Due to the lack of scientific information on the Pantanal milk potential, this work had the objective of determining the lactation period and a physical-chemical composition of the milk of cows in second order of parturition. The animals were managed in a pasture system rotated in mombaça grass (Panicum maximum) and individually supplemented with concentrate. The milking was performed mechanically twice a day and the milk weighed daily. The physical-chemical characteristics of the milk were evaluated by the ultrasound method and the lactation curves were estimated using the univariate parameter. The average milk yield was 5.34kg/milk/ day and the fat, protein, lactose and total non-fat solids contents were 5.3, 3.7, 6.0 and 10.7%, respectively. Lactation of the cows in second order of calving ended naturally at 180 days and the peak of milk production was reached between 51 and 60 days. Furthermore, there was no difference in milk composition in the different lactation periods.(AU)

Potencial leiteiro de animais da raça Pantaneira na região do Alto Pantanal do Mato Grosso do Sul / Dairy potential of pantaneira breed upper region of pantanal of Mato Grosso Sul

The Pantaneira breed is in danger of extinction. Due to the lack of scientific information on the Pantanal milk potential, this work had the objective of determining the lactation period and a physical-chemical composition of the milk of cows in second order of parturition. The animals were managed in a pasture system rotated in mombaça grass (Panicum maximum) and individually supplemented with concentrate. The milking was performed mechanically twice a day and the milk weighed daily. The physical-chemical characteristics of the milk were evaluated by the ultrasound method and the lactation curves were estimated using the univariate parameter. The average milk yield was 5.34kg/milk/ day and the fat, protein, lactose and total non-fat solids contents were 5.3, 3.7, 6.0 and 10.7%, respectively. Lactation of the cows in second order of calving ended naturally at 180 days and the peak of milk production was reached between 51 and 60 days. Furthermore, there was no difference in milk composition in the different lactation periods.(AU)

Eficiência produtiva ao desmame de vacas Nelore criadas no Pantanal / Productive efficiency to weaning of Nellore cows raised in the Pantanal

O trabalho objetivou avaliar a eficiência produtiva de vacas ao desmame de acordo com seu tamanho (peso) e estimar correlação fenotípica entre as características peso do bezerro ao desmame (PBD), peso da vaca ao desmame do bezerro (PVD) e relação desmame (RD = PBD/ PVD) de animais da raça Nelore criados no Pantanal de Mato Grosso do Sul. Foram utilizadas 706 observações para pares de dados de pesos de vacas e de bezerros da raça Nelore ao desmame criados em regime de pastejo. Foram formados seis grupos com base no peso de vaca ao desmame (GPVD) a partir dos desvios (40,73kg) de peso em relação à média geral do rebanho (420,56kg). Os grupos de vacas com menores pesos obtiveram maiores RD. As correlações fenotípicas entre PVD e PBD variaram de 0,05 a 0,26, enquanto para PVD e RD as correlações foram negativas e com variação de 0,11 a 0,25. As correlações fenotípicas entre PBD e RD apresentaram-se positivas e de alta magnitude (0,91 a 0,98). As maiores eficiências produtivas foram determinadas para vacas de pequeno a médio porte (327,20 a 438,62kg), além de estas serem menos exigentes quanto a nutrientes digestíveis totais (NDT). A seleção de vacas de tamanho médio (379, 83 a 461,29kg) apresenta-se mais vantajosa por gerar menor custo de mantença que as vacas maiores e produzir bezerros mais pesados que as vacas menores.(AU)

The study aimed to evaluate the productive efficiency of cow at weaning according to their size (weight) and estimated phenotypic correlation between the characteristics of weaning weight of calf and cow and weaning ratio of Nellore cattle raised in the Pantanal of Mato Grosso do Sul. 706 observations were used to weight data pairs of cow and calves at weaning. Six groups were formed based on the weight of cow at weaning from deviations (40.73kg) of weight in relation to the overall mean of the herd (420.56kg). The groups of cows with lower weaning weight have the highest weaning ratio. Phenotypic correlations of cow weight at weaning and weaning of calf weight ranged from 0.05 to 0.26, cow weight at weaning and weaning ratio were negative correlations ranging from -0.11 to -0.25. Phenotypic correlations between weaning of calf and weaning ratio were positive and of high magnitude (0.91 to 0.98). The highest efficiencies were determined for cows between 327.20 and 438.62kg, and are less demanding on total digestible nutrients (TDN). A selection of medium sized cows (379, 83 to 461.29kg) appears more interesting because it has lower maintenance costs than larger cows, and produces heavier calves than the smaller cows.(AU)

Características do sêmen congelado relacionadas à fertilidade in vitro em bovinos / Frozen semen characteristics associated to in vitro fertility in cattle

Objetivou-se verificar se há associação entre as técnicas laboratoriais de avaliação da integridade das membranas plasmática e acrossomal de espermatozoides congelados de touros usados na produção in vitro de embriões e as taxas de clivagem e de blastocistos. Amostras de sêmen congelado bovino (n = 39) foram avaliadas em 89 ensaios de fecundação in vitro, sendo consideradas apenas aquelas que possuíam um número ≥20 ovócitos, totalizando 2.738 ovócitos. Pós-Percoll® recuperou-se uma maior população de espermatozoides móveis e com membranas plasmática e acrossomal íntegras (P < 0,05). O percentual de células mortas e com reação acrossomal verdadeira (RAV) (FITC-PNA) explicou 25% da variação da taxa de clivagem. Vigor, percentual de vivos (eosina/nigrosina), vivos e RAV (trypan blue/Giemsa) e mortos e RAV (FITC-PNA) explicaram 41% da variação da taxa de blastocistos. A eficácia da produção in vitro de embriões está relacionada com diferentes atributos espermáticos, especialmente com aqueles associados à integridade da estrutura das membranas plasmática e acrossomal.

The aim of this work was to verify if laboratory techniques used to evaluate plasmatic and acrosomal membrane integrity of bovine frozen semen used in in vitro embryo production were associated with cleavage and blastocyst rates. Bovine frozen semen samples (n = 39) had been evaluated in 89 assays of fertilization in vitro being considered only those with ≥20 oocytes, with a total of 2,738 oocytes. After-Percoll® highest populations of motile spermatozoa were recovered, with intact plasmatic and acrosomal membranes (P < 0.05). The percentage of dead cells and those with true acrosomal reaction (TAR) (FITC-PNA) had explained 25% of the variation of the cleavage rate. Vigor, percentage of live (nigrosin/eosin), live and TAR (trypan blue/Giemsa), dead and TAR (FITC-PNA) had explained 41% of the variation of blastocyst rate. The effectiveness of in vitro embryo production is related with different spermatic attributes, especially with those associates to the structural integrity of plasmatic and acrosomal membranes.