Using two PGF(2α) treatments 14 days apart as a way to enhance estrus detection rate following the 2nd treatment is a reproductive management tool that continues to be used on large dairy farms. In one study, in cows with a functional CL and a dominant follicle, treatment with cloprostenol vs. dinoprost resulted in greater peripheral estradiol concentrations. The objective of the present study ...

Reproductive failure in inseminated cattle results from poor fertilization and embryo survival. Recent studies utilizing dairy and beef cattle indicate that fertilization rates are higher for nulliparous dairy and beef heifers and nonlactating beef cows than lactating beef and dairy cows and nonlactating dairy cows. Several factors affect fertilization rates, but the greatest impact was observe...

The objective of this study was to determine the long-term effects of feeding monensin on methane (CH4) production in lactating dairy cows. Twenty-four lactating Holstein dairy cows (1.46 +/- 0.17 parity; 620 +/- 5.9 kg of live weight; 92.5 +/- 2.62 d in milk) housed in a tie-stall facility were used in the study. The study was conducted as paired comparisons in a completely randomized design w...

Several temperature-humidity indexes (THI) have been used to estimate the degree of thermal stress experienced by dairy cows. The present objectives were to develop equations using meteorological variables that predicted rectal temperature of lactating cows in a subtropical environment and compare the goodness of fit of these equations to those using 8 different THI. Rectal temperature was meas...

The objective was to determine whether transfer of fresh or vitrified embryos produced in vitro with sex-sorted semen improves pregnancy and calving rates during summer in lactating dairy cows compared with artificial insemination (AI). Lactating dairy cows (n=722) were enrolled during summer months at 2 commercial dairies in Central Texas and randomly assigned to 1 of 3 treatments: AI with con...

S ADSA Student Affiliate Division * Author Presenting Paper Original Research/Independent Study Undergraduate Paper Presentations 957 The luteolytic potential of reduced doses of prostaglandin. J. Brinkerhoff*, R. Silcox, J. Donley, and C. Kubo, Brigham Young University, Provo, UT. Prostaglandin (PGF) and its analogs have greatly contributed to managing the reproductive performance of dairy her...

The transition from pregnant, non-lactating to non-pregnant, lactating is too often a disastrous experience for the cow. Most of the metabolic diseases of dairy cows milk fever, ketosis, retained placenta, and displacement of the abomasum occur within the first 2 wk of lactation. In addition to metabolic disease, the majority of infectious disease experienced by the dairy cow, especially mastit...

The body condition scoring (BCS) is a subjective estimate of the energy reserves in adipose tissues of a dairy cow. It is an acceptive, noninvasive, quick and inexpensive method to estimate degree of fatness. It is a means of accurately determining body condition of dairy cows, independent of body weight and frame size [1]. It is evinced that the profile of lactating cows in milch barn is diffe...

the present study was conducted to evaluate the effects of extruded linseed on milk production,dry matter intake and reproduction performance of 300 holstein lactating cows (35±15 days in milk;41±9/8 kg/day of milk production). cows were placed in a completely randomized design of 2treatments (concentrate containing 7 percent of extruded linseed vs. control), (150 cows pertreatment). cows were ...