The objective of this trial was to investigate correlations among the California Mastitis Test, somatic cells count (SCC), and milk yield. Milk samples were collected from thirty-eight Murrah buffalo cows in the years of 2002 and 2003. Milking management included cleaning teats with individual paper towel followed by attachment of the milk units in cows that were milked once daily. The CMT was done immediately after teat cleaning and collected milk samples were sent to the laboratory for determination of […]

Reproduction efficiency of Holstein x Gir crossbred animals in Brazilian dairy farms were evaluated using data provided by the Brazilian Association of Girolando. A total of 2,600 records of age at first calving (IPP) and 3,763 records of calving intervals (IDP) were analyzed using the SAS® GLM procedure. Estimates of genetics effects: additive difference between Holstein and Gir breeds, dominance and additive x additive epistatic effects were obtained by regression models including genetic groups to model the performance of crossbred […]

It was studied the effects of replacing ground corn with coffee hulls on intake, apparent digestibility, and milk production and composition of lactating dairy cows. Twelve Holstein-Zebu dairy cows were blocked by days in milk and randomly assigned to three 4 x 4 Latin squares. The following levels of coffee hulls were included in the concentrate portion of the diet: 0.0, 8.75, 17.5, or 26.25% of dry mater (DM). Diets were formulated to be isonitrogenous (14% CP) and contained a […]

The effects of supplements containing different rumen-undegradable protein (RUP) levels on the ruminal passage rate of particles and liquid of steers grazing Brachiaria brizantha were evaluated in this study. Samples were collected in two seasons of the year (season 1 May, June and July/2000 and season 2 March, April and May/2001). In season 1, animals were housed in individual stalls and were fed supplements containing 20, 40 or 60% RUP plus Brachiaria brizantha hay and had free access to a […]

Data consisting of individual records of male and female animals of purebred Bos Indicus beef cattle (Nellore, Guzerá, Gir and Indubrasil) weighted every three months from birth to 24 months of age available from National Archive of Brazilian Zebu Breeders Association (ABCZ) were used to evaluate two alternatives (co)variance analyses for body weight. In the first analysis the Box-Cox family transformation yil = (yl

The variation of cortisol and thyroid hormones in Corriedale sheep bred in a tropical environment was evaluated. Fourteen males and seven females were observed in a climatic chamber at 45ºC for nine days, eight hours per day. Rectal temperature (TR), respiratory rate (FR), air temperature (TA) and air humidity (PV) were recorded. The animals were ranked according to their responses for TR and FR and then the five highest (A group) and five lowest (NA group) ranked animals were selected. […]

Twelve lactating Holstein dairy cows were assigned to three 4×4 Latin squares to evaluate the effects of feeding corn silage or different dietary ratios of sugarcane and concentrate on nutrient intake, apparent digestibility, milk composition and yield, and body weight change. The diets contained 60% corn silage or 60, 50, and 40% of sugarcane supplemented with 1% of urea + ammonium sulphate (9:1). No significant differences were observed between the diet with 60% of corn silage and that with 40% […]

The influence of a priori information on animal genetic evaluation was studied using a simulated 3.000 centimorgans genome, for a single trait governed by 800 loci, with two alleles for locus, and heritability varying from 0.40 to 0.60. Three populations with different sizes were derived from the base-population constituted by 1.500 males and 1.500 females: POP1 (100 animals), POP2 (300 animals) and POP3 (1.600 animals). Three a priori information levels were considered: no-informative priors (PNI), slightly informative priors (PPI) and […]

Weight records of 35.308 Tabapuã animals born between 1975 and 2000, made available by the Brazilian Zebu Breeders Association (ABCZ), were used to estimate genetic parameters for growth from birth to 570 days of age. Univariate analyses were used to fit three different models including fixed effects of contemporary group (owner, herd, sex, breeding management, year-month of birth and year-month of weight) and age of calf and age of dam (linear and quadratic) as covariates. Model 1 included only the […]

The objective of this trial was to study the effects of different dietary levels of crude protein (CP) on intake and apparent total tract, intestinal, and ruminal digestibilities of nutrients in Holstein x Zebu steers. The diets contained [dry matter (DM) basis]: 10.5, 12, 13.5, or 15% of CP and a forage (Tifton 85):concentrate ratio of 65:35. Four castrated animals averaging 487.3 kg of body weight at the beginning of the trial and fitted with both abomasum and rumen cannulas […]