The objective of this study was to investigate the effect of group size on behavior, growth, health, and welfare of veal calves. Holstein-Friesian bull calves (n=168; 44±3 d of age) were assigned randomly to 1 of 3 treatments of group housing with 2, 4, or 8 calves per pen. The pens used for housing were 3 by 1.20 m (2 calves per pen), 3 by 2.40 m (4 calves per pen), and 3 by 4.80 m (8 calves per pen), supplying a total pen space allowance of 1.82 m2/calf, regardless of pen size. Behavior was recorded from video data throughout the day from 0700 to 1900 h during a single day each month for 5 mo using scan sampling every 5 min within 30-min observation sessions. On d 0, 1, 5, 14, 42, and 70 after grouping, continuous focal sampling around feeding time (30-min intervals before, during, and after feeding) focused on oral and aggressive behaviors. Calves housed in large groups (4 or 8 calves per pen) showed more (P≤0.001) conspecific contact, walking, and standing and less (P<0.001) manipulation of objects, self-licking, and lying when compared to calves housed in small groups (2 calves per pen). Group size had no effect on play behavior (P=0.11) throughout the experiment. During feeding times group size had no (P≥0.07) effect on any behavioral patterns except for duration of conspecific contact (P<0.01). Aggression at feeding time was not (P>0.23) affected by treatment. Group size treatments were similar for hip height change (P=0.41) and heart girth change (P=0.18) over the duration of the experiment; however, both hip height and heart girth increased (P=0.001) with calf age. During mo 1, calves in groups of 8 or 4 coughed more than calves in groups of 2 whereas calves in groups of 8 coughed more than calves in groups of 4 or 2 in mo 2 (treatment×month, P=0.03). Furthermore, during mo 4, calves in groups of 8 had less nasal discharge than calves in groups of 2 or 4 (treatment×month, P=0.02). Ocular discharge, ears, and fecal scores did not differ (P≥0.05) among treatments. Plasma cortisol was not (P≥0.37) affected by group size. The number of veal calves in a group when given the same space did not affect production and physiological indicators of welfare but had a transient effect on health during the 5-mo finishing period. If increased play and social contact and decreased aggression are considered as primary indicators of welfare, group size did not alter calf welfare.

Antimicrobial resistance (AMR) is a global issue for both human and animal health. Antimicrobial drug (AMD) use in animals can contribute to the emergence of AMR. In January 2018, California (CA) implemented legislation (Senate Bill 27; SB 27) requiring veterinary prescriptions for medically important AMD use in food animals. The objective of our survey was to characterize AMD use, health management, and AMD stewardship practices of adult cows on CA dairies since the implementation of SB 27. In 2019, we mailed a questionnaire to 1282 California dairies. We received a total of 131 (10.2%) survey responses from 19 counties in CA. Our results showed that 45.6% of respondents included a veterinarian in their decision on which injectable AMD to purchase. Additionally, 48.8% of dairy producers included a veterinarian in their decision on which AMDs were used to treat sick cows. The majority (96.8%) of dairy producers were aware that all uses of medically important AMDs require a prescription. Approximately 49% of respondents agreed or strongly agreed that AMD use in livestock does not cause problems in humans. The survey documents antimicrobial use and stewardship practices in CA’s dairy industry and focus areas for future research and education.

Although a number of welfare assessment methods have been developed for poultry, none have been evaluated for use in commercial duck farms. The primary objective of the study was to evaluate the inter-rater reliability and relative accuracy of 4 duck welfare assessment strategies. Over 2 experiments, 12 flocks of commercial meat ducks (5,850 to 6,300 ducks/flock) aged 30 to 34 D were evaluated. During experiment 1, six flocks were evaluated using 2 welfare assessment methods: transect walks ( TW ) and catch-and-inspect ( CAI ). During TW, 2 observers walked predetermined transects along the length of the house and recorded the number of ducks per transect that were featherless, were dirty, were lethargic, had bloody feathers, had infected eyes, and/or had plugged nostrils or were found dead. During CAI, a total of 150 ducks per flock were corralled and individually evaluated. The same welfare indicators were assessed using both methods. During experiment 2, six flocks were initially evaluated using CAI, TW, and a distance evaluation ( DE ; a total of 50 ducks per flock evaluated from a walking distance) and then reassessed within 24 h during the loadout ( LO ) process. Data were analyzed in SAS (version 9.4) to determine the observer and method effects on the incidence of welfare indicators. Interobserver reliability was high ( P > 0.05) across methods for most welfare indicators. The assessment method affected the measured outcome variables in both experiments ( P < 0.05). CAI resulted in higher estimated incidences of most welfare indicators than TW (experiment 1 and 2) and LO (experiment 2). DE yielded intermediate results compared with other methods (experiment 2). Results obtained using TW and LO were most similar, the only difference being the number of dead birds observed using each method ( P < 0.0001). The average time required for CAI, TW, DE, and LO was 2.40 ± 0.004, 1.12 ± 0.02, 1.54 ± 0.001, 3.56 ± 0.006 h, respectively. Bootstrapping analyses showed that the observed welfare indicator prevalence estimates were affected by the number of transects (TW) and number of birds (CAI) sampled.