Spring calving Angus and Angus x Hereford multiparous cows were utilized to determine the effects of intramammary treatment with penicillin G procaine (200,000 IU) and novobiocin (400 mg) at the time of weaning on udder health and calf growth after the subsequent calving. Cows were stratified by age and breed and assigned randomly to receive intramammary treatment (n = 99) at weaning or as untr...

A total of 245187 records of the first three lactations of 131126 Holstein cows in tropical conditions were used to estimate the genetic (co)variance components between age at calving and its respective milk productions. A multivariate analysis of six traits was performed. Heritability for age at calving (h2AC) and milk yield (h2MY) decrease from the ...

This study was designed to investigate causes of culling in industrial dairy herds in Fars province and to describe the pattern of reason-specific culling with respect to age of animal and interval from calving to culling. A total number of 9 dairy herds were selected for the study and information about culling reasons, birth date, last calving date and culling date was collected for culled cow...

During summer 2013 we installed a network of 19 GPS nodes at the ungrounded margin of Helheim Glacier in southeast Greenland together with three cameras to study iceberg calving mechanisms. The network collected data at rates up to every 7 s and was designed to be robust to loss of nodes as the glacier calved. Data collection covered 55 days, and many nodes survived in locations right at the gl...

Calving records (n = 6,763) obtained from first, second, and third parities of 3,442 spring-calving, Uruguayan Aberdeen Angus cows were used to estimate heritabilities and genetic correlations for the linear trait calving day (CD) and the binary trait calving success (CS), using models that considered CD and CS at 3 calving opportunities as separate traits. Three approaches were defined to hand...

The objective of this study was to compare linear models and survival analysis for genetic evaluation of ovulatory disorders, which included veterinary treatments of silent heat/anestrus and cystic ovaries. Data of 23 450 daughters of 274 Austrian Fleckvieh sires were analyzed. For linear model analyses, ovulatory disorders were defined as a binary response (presence or absence) in the time per...

MILK FEVER, also called parturient paresis and parturient hypocalcemia, is an aifection of cows occurring shortly after calving. It is characterized by paralysis of the motor and sensory nervous apparatus. Despite its name, milk fever usually is not accompanied by fever. There is always, however, a marked and rapid lowering of the blood calcium, so that the name "parturient hypocalcemia," which...

A 3-yr study evaluated late winter (Feb), early spring (Apr), and late spring (Jun) calving systems in conjunction with varied weaning strategies on beef cow and calf performance from Northern Great Plains rangelands. Crossbred cows were randomly assigned to one of three calving systems (on average n= 168.calving system(-1).yr(-1)) and one of two weaning times (Wean 1, 2) within each calving sy...