Effects of 2 wintering practices on behavioral and physiological indicators of welfare of nonlactating, pregnant dairy cattle in a pasture-based system.

In countries with pasture-based dairy systems and relatively cold winters, such as New Zealand, it is common to manage pregnant, nonlactating cows on forage crop paddocks rather than pasture, due to slow pasture growth rates. Wintering dairy cattle on grazed crops can compromise welfare if wet and muddy underfoot conditions occur, which can reduce lying. This study investigated behavioral and physiological indicators of welfare of cows under 2 wintering practices: cows managed on and grazed kale crop (Brassica oleracea), and cows managed on pasture with baled hay. Following dry-off (d 0), 80 cows were randomly assigned to 1 of the 2 wintering practices (40 cows/practice) and monitored between d 4 and 32 (phase 1). During this period, lying and stepping behavior was continuously recorded using leg-based accelerometers. Blood samples were obtained at d 0 and 32 for measurements of thyroxine (T4), nonesterified fatty acids (NEFA), white blood cells (WBC), and red blood cells. All data for phase 1 were presented descriptively due to the lack of treatment replication. Daily mean air temperature during this period was 5.2°C (range: 0.0-10.7°C), and rainfall was 1.1 mm/d (range: 0-5.6mm/d). Between d 4 and 32, cows in both groups spent similar amounts of time lying (pasture with hay cows: 8.9 h/24 h ± 2.57, kale crop cows: 8.7 h/24 h ± 3.06, mean ± SEM). Both groups reduced their lying on wet and cold days, and there was evidence of rebound lying once unfavorable weather conditions stopped. Cows on kale crop had numerically higher NEFA and lower WBC compared with cows managed on pasture, although most physiological values were within normal ranges. In a second phase of the study (d 34 and 35), cows were managed under controlled, replicated conditions in the 2 wintering practices using typical on-farm stocking rates (2 or 4 cows per group in the pasture with hay and kale crop treatments, respectively; n = 10 groups/treatment). During this period, cow behavior, skin and surface temperatures, hygiene scores, feed intakes, and ground conditions were measured. Weather conditions during the 48-h exposure were mostly cold and dry (mean air temperature: 7.8°C, range: -2.2 to 20.5°C). Cows managed on pasture with hay spent more time lying down on the first day of exposure; however, this was likely due to less space being available to kale cows on this day. Cows managed on pasture with hay ruminated more than cows on kale crop on both days of observations (d 1: 37.9% vs. 30.9% of observations, d 2: 36.8% vs. 28.7% of observations for pasture with hay and kale crop groups, respectively) and were lying more often in postures indicative of greater thermal comfort. Cows managed on pasture with hay had higher skin and surface temperatures compared with cows on kale crop, whereas cows on kale crop had dirtier coats. Results suggest that opportunities for thermal comfort were greater for cows managed on pasture with hay bales, which may be due to increased rumination activities and more insulated lying areas.

Evaluating the immediate effects of hoof trimming on dairy goat hoof conformation and joint positions.

Hoof overgrowth in commercial housed dairy goats is a major health and welfare concern; thus, it is important to better understand hoof trimming, a priority practice which addresses hoof growth. We evaluated the immediate effects of trimming on external conformation, internal joint positions, and hoof wall overgrowth of front and hind hooves. Eighty female goats were enrolled. Pre and post hoof trimming data were collected at 13, 17, 21 and 25 months of age. Overall, before trimming, a high percentage of hooves were scored as overgrown (77.8%). Trimming decreased the percentage of overgrown hooves (17.6%: P < 0.001) and other moderate/severe conformational issues: dipped heels (49.3% vs. 26.7; P < 0.001), misshaped claws (37.0% vs. 17.6%; P < 0.001), splayed claws (73.7% vs. 56.7%; P < 0.001). More hind than front hooves had dipped heels pre-trimming and (91.3% vs. 7.3%; P < 0.001) and post-trimming (52.8% vs. 0.6%; P < 0.001); over half of the hind heels were not restored to an upright position. A greater proportion of toe length was removed from the hind hooves compared to the front (0.50 vs. 0.43, P < 0.001), with the greatest proportion of hoof wall overgrowth removed from the hind hoof medial claw at the 13-month assessment (P < 0.001). Following trimming, distal interphalangeal joint angle decreased more in hind compared to front hooves (11.0° vs. 6.9°; P < 0.001); distal interphalangeal joint height decreased (0.21 cm, P < 0.001), and proximal interphalangeal joint, and heel, angles increased (7.76° and 8.93°, respectively; P < 0.001). Trimming did not restore conformation of all hooves when trimmed every 4 months, suggesting a need to investigate reasons for underlying poor conformation, including trimming frequency.