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Transition dairy cows are vulnerable to the negative consequences of depressed feed intake around calving. Competition can decrease feeding activity in midlactation cows, but the effects of competition on the transition cow are not well understood. The objective was to test the effect of competition on the behavior and feed intake of transition cows. Standing behavior, feeding behavior, and dry matter intake were monitored from 1 wk before to 2 wk after calving for 36 Holstein dairy cows. Displacements at the feed bins were recorded the week before calving. Cows were assigned to either competitive (2:1 cows:feed bin) or noncompetitive (1:1 cow:feed bin) treatments. Treatment groups were balanced for parity and baseline feeding measures, resulting in 8 primiparous and 10 multiparous cows per treatment. Competition increased the number of displacements at the feed bins for both primiparous and multiparous cows. Primiparous cows had no change in feed intake or standing time when fed in a competitive environment, but did increase the time spent for each meal during the week before calving (28 ± 1.5 vs. 24 ± 1.5 min/meal). In the week before and after calving, competitively fed multiparous cows had a lower feeding time per visit than noncompetitively fed cows (4.2 ± 0.5 vs. 5.8 ± 0.5 kg/visit and 5.3 ± 0.7 vs. 7.0 ± 0.7 kg/visit, respectively). Multiparous cows ate at a faster rate 2 wk after calving (142 ± 11 vs. 105 ± 11 g/min). Multiparous cows in the competitive treatment increased the time they spent standing (without eating) during the week after calving compared with cows in the noncompetitive treatment (820 ± 44 vs. 649 ± 44 min/d). Feeding rate was correlated with a displacement index in multiparous cows, whereby cows with lower displacement indices ate more rapidly. Results indicate that restricting access to feed increases displacements regardless of parity, and alters the feeding and standing behavior of primiparous and multiparous cows differently. [ABSTRACT FROM AUTHOR]

The main objective was to assess the consistency in competitive success across 3 common resources available to dairy cows housed in free-stall barns. Specifically, we determined if those cows that displaced other cows most often at the feed bunk (high-ranking) had priority of access to free-stalls or a mechanical brush. Our secondary objective was to determine if the displacements at each resource were a function of usage of that resource. These objectives were tested using 6 groups of 12 lactating dairy cows housed in pens with 0.6 m of bunk space per cow, 1 free-stall per cow, and 1 mechanical brush per pen. Time-lapse video was used to quantify the time spent feeding, in the stalls, and using the mechanical brush. The incidence of displacements at the feed alley and lying area was measured for 3 d consecutively. Usage was lower for the brush, so displacements were monitored for 14 d consecutively. The individual measures of competitive success were not highly correlated between resources indicating a cow that frequently displaced other cows for access to one particular resource did not always do so when accessing the other resources. Competition at the feeder was responsible for 87.6 ± 1.4% of displacements observed throughout the experiment, indicating that gaining access to feed was a high priority for cows. These results suggest that competitive success by dairy cows may vary according to each cow's motivation to access the resource. [ABSTRACT FROM AUTHOR]

The objective of this study was to validate a system for monitoring individual feeding and drinking behavior and intake in group-housed cattle. A total of 42 Holstein cows were tested with access to 24 feed bins and 4 water bins. For the purposes of this validation experiment, we focused our observations on 4 water bins and 13 feed bins. When the cow approached the feed or water bin, an antenna detected the cow's unique passive transponder and lowered the barrier, allowing the cow access to the feed or water. For each visit to the bin, the system recorded the cow number, bin number, initial and final times and weight and calculated the visit duration and intake. Bins were also monitored by direct observation and time-lapse video recording for 2 d per bin, with observations for 4 and 6 h/d for the feed and water bins, respectively. Data from direct observations were compared with the electronic data recorded by the system. Feed disappearance over 24 h was assessed by using an external scale over 3 consecutive 24-h periods, and these values were compared with the sum of intakes across all visits to that bin for the same time periods. The system showed a high specificity (100%) and sensitivity (100 and 99.76% for the feed and water bins, respectively) for cow identification. The duration of the feeding and drinking visits and the feed and water intake per visit, as estimated by the monitoring system, were highly correlated with those obtained by direct observation (R² ≥ 0.99 in all the cases). The comparison of the total feed that disappeared from each bin in 24 h with the sum of the feed cows consumed from that bin during the same period differed by less than 1 kg (29.92 ± 0.90 kg and 29.24 ± 0.90 kg as estimated by manual weighing and by the electronic system, respectively). This difference could be attributed to changes in feed moisture during the 24-h period. In conclusion, this electronic system is a useful tool for monitoring intakes and feeding and drinking behavior of loose-housed cows. [ABSTRACT FROM AUTHOR]

Cows prefer to spend more time lying down in free stalls with more bedding, but no research to date has addressed the effects of bedding quality. Bedding in stalls often becomes wet either from exposure to the elements or from feces and urine. The aim of this study was to test the effect of wet bedding on stall preference and use. Four groups of 6 nonlactating Holstein cows were housed in free stalls bedded daily with approximately 0.1 m of fresh sawdust. Following a 5-d adaptation period, each group of cows was tested sequentially with access to stalls with either dry or wet sawdust bedding (86.4 ± 2.1 vs. 26.5 ± 2.1% dry matter), each for 2 d. These no-choice phases were followed by a 2-d free-choice phase during which cows had simultaneous access to stalls containing either wet or dry bedding. Stall usage was assessed by using 24-h video recordings scanned at 10-min intervals, and responses were analyzed by using a mixed model, with group (n = 4) as the observational unit. The minimum and maximum environmental temperatures during the experiment were 3.4 ± 2.2 and 6.8 ± 2.5°C, respectively. When cows had access only to stalls with wet bedding, they spent 8.8 ± 0.8 h/d lying down, which increased to 13.8 ± 0.8 h/d when stalls with dry bedding were provided. Cows spent more time standing with their front 2 hooves in the stall when provided with wet vs. dry bedding (92 ± 10 vs. 32 ± 10 min/d). During the free-choice phase, all cows spent more time lying down in the dry stalls, spending 12.5 ± 0.3 h/d in the dry stalls vs. 0.9 ± 0.3 h/ d in stalls with wet bedding. In conclusion, dairy cows show a clear preference for a dry lying surface, and they spend much more time standing outside the stall when only wet bedding is available. [ABSTRACT FROM AUTHOR]

Metritis is a disease of particular concern after calving because of its profound negative effects on the reproductive performance of dairy cows. Cows at risk for metritis have shorter feeding times in the days before calving but prepartum dry matter intake (DMI) and water intake may also be useful in identifying cows at risk for this disease. Feeding, drinking, and intake measures may also be affected by social interactions among group-housed cows. The objective of this study, therefore, was to measure intake, feeding, drinking, and social behavior to determine which measures could identify cows at risk for metritis after calving. Feeding and drinking behavior and intake measures were collected from 101 Holstein dairy cows from 2 wk before until 3 wk after calving using an electronic monitoring system. Social behavior at the feed bunk was assessed from video recordings. Metritis severity was diagnosed based on daily rectal body temperature as well as condition of vaginal discharge that was assessed every 3 d after calving until d +21. In this study, 12% of cows were classified as severely metritic and 27% as mildly metritic. Prepartum feeding time and DMI were best able to identify cows at risk for metritis. Cows that developed severe metritis spent less time feeding and consumed less feed compared with healthy cows beginning 2 wk before the observation of clinical signs of infection. For every 10-min decrease in average daily feeding time during the week before calving, the odds of severe metritis increased by 1.72, and for every 1-kg decrease in DMI during this period, cows were nearly 3 times more likely to be diagnosed with this disorder. During the week before calving, cows that were later diagnosed with severe metritis had lower DMI and feeding times during the hours following fresh feed delivery. During this period these cows also engaged in fewer aggressive interactions at the feed bins compared with cows that remained healthy. This research is the first to show that social behavior may play an important role in transition cow health. Research is now required to determine how management should be changed to reduce or prevent illness in transition dairy cows. [ABSTRACT FROM AUTHOR]

Using a combination of radioisotopic counting and Chromatographic detection techniques, the kinetics and metabolic fate of deoxynivalenol (DON) in plasma, urine and bile were studied in lactating sheep, as was the transmission of residues to milk. Following intravenous administration, the plasma clearance of 14C‐DON‐derived radioactivity was rapid and followed a tri‐phasic decay curve comprised of a bi‐exponential decrease in DON (rapid distribution phase, t1/2α = 16.2 min; slower elimination phase t1/2 β = 66.5 min) and the formation and elimination (t1/2ß = 188.0 min) of its major plasma metabolite, DON‐glucuronide conjugate, which accounted for 13% of the plasma radioactivity levels. DON was rapidly cleared from the body by metabolism to 7 possible metabolites, which were excreted essentially in the urine (91%) and to a lesser extent in the bile (6%). Most (67%) of the recovered radioactivity was in the form of the glucuronide conjugates of DON (54%) and the de‐epoxide metabolite, DOM‐1 (13%). Excretion of unmetabolized DON accounted for 11%. The remaining recovered dose (18%) comprised of minor amounts of DOM‐1 (6%), DON‐sulfate conjugate (2%) and 3 unidentified radioactive components (10%). Studies on the presence of DON‐derived residues in milk indicated that, relative to the dose, only trace amounts were transmitted following either oral or iv administration of the toxin. [ABSTRACT FROM PUBLISHER]