Heat abatement during the pre-weaning period: effects on the nasal microbiota of Holstein male calves.

Housing strategies to alleviate the negative effects of heat stress on the performance of pre-weaned dairy calves have become a focus of research in recent years. Experiments evaluating such strategies have focused on thermoregulatory responses, behavior, and performance. To date, no experiments have evaluated their effects on the microbiota of the upper respiratory tract.

Targeted reproductive management for lactating Holstein cows: Reproductive and economic outcomes of Double-Ovsynch compared with a targeted approach based on resumption of estrus.

Accessibility to automated monitoring devices (AMD) has led to exploration of alternative reproductive management to ovulation synchronization protocols (OvSP) for first postpartum artificial insemination (AI) according to the cow's early postpartum estrus characteristics (EPEC). We hypothesized that pregnancy and economic outcomes of cows subjected to a targeted reproductive management (TRM) are not inferior to those of cows subjected to an OvSP for the first AI. This was a noninferiority, randomized clinical trial.

Relationships between activity monitoring device data and ovarian, uterine, hormonal, and pregnancy variables in beef cows.

Implementing accelerometer technologies in beef operations is an alternative to increase precision in estrous detection. We hypothesized that (1) the accelerometer algorithm has similar accuracy in detecting behavioral estrus as does visual observation of pressure-sensitive sensors (estrus patches) in grazing beef cows; (2) variables measured by the accelerometer, such as estrus intensity, are associated with hormonal, ovarian, and uterine variables monitored before, during, and after estrus; and (3) the accelerometer variables are associated with the probability of pregnancy in grazing beef cows submitted to embryo transfer (ET). Fifty cows were fitted with accelerometer and patches to detect estrus after a synchronization protocol in eight subsequent rounds.

Targeted reproductive management for lactating Holstein cows: Economic return.

Targeted reproductive management (TRM), employing automated monitoring devices (AMD), is as an alternative to the blanket adoption of ovulation synchronization protocols (OvSP) for first postpartum AI and a means of reducing the use of OvSP for re-insemination of nonpregnant cows. We hypothesized that a TRM that relies heavily on AI of cows on AMD-detected estrus improves reproductive performance and economic return. Early-postpartum estrus characteristics (EPEC) of multiparous (n = 941) cows were evaluated at 40 and 41 DIM (herds 1 and 2, respectively) and EPEC of primiparous (n = 539) cows were evaluated at 54 and 55 DIM (herds 1 and 2, respectively).

A randomized trial on the effects of heat abatement during the pre-weaning phase on growth and reproductive performance of heifers and health, reproductive and productive performances of cows.

Evaluation of heat stress abatement for pre-weaned dairy calves is a rare endeavor. We aimed to assess the impacts of cooling the environment of pre-weaned calves through ceiling fans on their performance after weaning and during their first lactation. We randomly assigned female Holstein calves to one of two treatment at birth (day 0): individual frame-wire hutches in a non-cooled barn ("SH", n = 125) and individual frame-wire hutches in a barn equipped with ceiling fans ("SHF", n = 101).

Targeted reproductive management for lactating Holstein cows: Reducing the reliance on exogenous reproductive hormones.

Adoption of automated monitoring devices (AMD) affords the opportunity to tailor reproductive management according to the cow's needs. We hypothesized that a targeted reproductive management (TRM) would reduce the use of reproductive hormones while increasing the percentage of cows pregnant 305 d in milk (DIM). Holstein cows from 2 herds (n = 1,930) were fitted with an AMD at 251.

A randomized trial on the effects of heat stress abatement on environmental conditions and growth, feed efficiency, and concentration of metabolites of pre-weaned female Holstein calves.

Heat abatement strategies for pre-weaned calves are seldom adopted. Our objectives were to determine the effects of adding fans to barns on environmental conditions and growth, feed efficiency, concentration of metabolites and health of pre-weaned female Holstein calves. Calves born from July 15th to 30th of 2019 were eligible for enrollment.

Heat abatement during the pre-weaning period: effects on lying behavior and disbudding-related responses of male Holstein calves.

Strategies to abate heat stress are seldom adopted for pre-weaned dairy calves and little is known about their effects on behavior and pain sensitivity of youngstock. Our objectives were to determine the effects of heat stress abatement on lying behavior and disbudding-related pain sensitivity, wound healing, and change in intake. Male Holstein calves (n = 60; 0 to 68 d of age) were assigned randomly at birth (d 0) to 1 of 3 treatments: hutch outdoors with 50% of its area covered with plywood (control = 20), hutch in a barn with no cooling (SH = 21), and hutch in a barn with ceiling fans (SHF = 19).

Heat abatement during the pre-weaning period: effects on growth, feed efficiency, metabolites, and insulin of male Holstein calves.

Heat stress abatement strategies for pre-weaned dairy calves are seldom evaluated. An experiment was conducted to evaluate the effects of housing calves under a barn and provision of fans to calves housed under a barn on calfhood performance. The experiment was conducted in a dairy in southern Georgia, USA.