Invited review: Lying time and the welfare of dairy cows.

Adequate time lying down is often considered an important aspect of dairy cow welfare. We examine what is known about cows' motivation to lie down and the consequences for health and other indicators of biological function when this behavior is thwarted. We review the environmental and animal-based factors that affect lying time in the context of animal welfare.

Effect of age of introduction to an automated milk feeder on calf learning and performance and labor requirements.

Group housing of dairy calves with automated milk feeders (AMF) is increasingly being used, but the effect of introducing calves to the AMF at a very young age (<24 h) on calf performance, health, and welfare, as well as farm personnel labor requirements are unknown. The objective of this controlled trial was to investigate whether early (<24 h after birth) introduction of calves affects the time to learn how to drink from the AMF, labor requirements for feeding milk during the learning phase, and average daily gain during the milk-feeding period compared with calves conventionally introduced at 5 d of age. Sixty Holstein calves (heifers and bulls) were assigned at birth to either early introduction (<24 h after birth) or conventional introduction (at 5 d of age) to the group pen with AMF.

Associations between management practices and within-pen prevalence of calf diarrhea and respiratory disease on dairy farms using automated milk feeders.

Data on management practices used with automated milk feeders (AMF) are needed to identify factors associated with calf health in these systems. The objectives of this observational, longitudinal, cross-sectional study were to estimate the prevalence of calf diarrhea (CD) and bovine respiratory disease (BRD), and to identify factors associated with prevalence of these diseases at the pen level on dairy farms feeding milk to group-housed calves with AMF. Seventeen dairy farms with AMF in Ontario, Canada, were visited 4 times, seasonally, over 1 yr.

A survey of dairy calf management practices among farms using manual and automated milk feeding systems in Canada.

Dairy calves in North America traditionally are housed individually and fed by manual milk feeding (MMF) systems with buckets or bottles. Automated milk feeders (AMF) allow for more natural milk feeding frequencies and volumes, and calves are usually housed in groups. The objectives of this study were to (1) determine the prevalence of various milk-fed calf management and feeding practices and (2) compare these practices between dairy farms using MMF and AMF systems.

Reciprocated cross sucking between dairy calves after weaning off milk does not appear to negatively affect udder health or production.

Cross sucking by dairy calves occurs most commonly before weaning, but is of most concern in older animals where it has been claimed to cause mastitis and udder damage. Providing ad libitum milk allowance via a teat and gradual weaning reduces cross sucking, but low levels of this behavior still persist. Our aims were to understand why this behavior persists in some calves after weaning off milk and to examine whether individuals which are cross sucked postweaning are more likely to sustain teat injury or develop mastitis during their first lactation.

Using automated feeders to wean calves fed large amounts of milk according to their ability to eat solid feed.

Dairy calves weaned off milk at an early age show signs of hunger and can lose weight. We examined whether using automated feeders to wean calves according to individual voluntary solid feed intake reduced the effects of weaning. Female Holstein calves were housed in groups of 5 to 9.

Automated and visual measurements of estrous behavior and their sources of variation in Holstein heifers. II: Standing and lying patterns.

Lying (LY) and standing (ST) behavior of Holstein heifers (n = 57) was studied from Day -7 to Day +2 relative to estrus (Day 0) using leg-mounted accelerometers. A total of 269 estrus episodes were studied. The objectives were to quantify the effects of estrus on ST and LY patterns, identify sources of variation, and provide insight into new approaches for the use of sensors in estrus detection.

Urination and defecation by group-housed dairy calves.

A better understanding of when and where group-housed calves are most likely to defecate or urinate might permit improved housing design or more efficient use of cleaning routines. However, this is the first study to address the urination and defecation habits of calves. The primary aims of this study were to report the daily frequency of calves' urination and defecation and determine when and where group-housed dairy calves defecate and urinate most frequently.

Technical note: a comparison of 2 methods of assessing lameness prevalence in tiestall herds.

We compared 2 methods for identifying lame cows and estimating the prevalence of lameness in tiestalls. Cows (n=320) in 9 tiestall herds were scored as lame both by the presence of limping while walking and by stall lameness scores (SLS). The SLS was based on the number of the following behaviors that the cow showed while standing in the tiestall: weight shifting, standing on the edge of the stall, uneven weight bearing while standing, and uneven weight bearing while moving from side to side.

Use of three-dimensional acceleration sensing to assess dairy cow gait and the effects of hoof trimming.

The aim of this study was to assess the use of three-dimensional acceleration sensing to describe the gait of dairy cows and the effect of hoof trimming. In Trial 1, a three-dimensional acceleration sensor was attached to the carpal region of a front leg of six Holstein cows who were then walked for 9 m. Results showed that measures of acceleration could clearly show the presence of steps, which were divided into an acceleration phase, which involved the hoof descending to and ascending from the ground, and a non-acceleration phase, which included the swing phase.