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Seventy-two Angus feedlot bulls were observed to determine the effects of implanting with zeranol (0, 36 or 72 mg; four groups of six/level) at 8 mo of age (d 0), and of castration midway through the feedlot period (d 115) vs remaining intact (six groups/treatment) on sexual, agonistic and handling behaviors. All 36-mg-treated cattle were re-implanted (36 mg) on d 112; 72-mg-treated cattle were not re-implanted. Each group was observed for a total of 8 h at the time of sunset ± 30 min for sexual and agonistic behaviors during the trial. Observations on handling were made during 15 weighings and on seven occasions in the pens of the animals. Zeranol did not affect sexual or agonistic behavior. Before imposition of castration, implanted bulls entered the scales more quickly, took longer to stand still on the scales and were less quiet than non-implanted bulls (P<05). Castration decreased the sexual behaviors of masturbation (.75 vs .08 · pen−1·h−1; P<.05), attempted mounts (.75 vs .33 · pen−1· h−1; P<.05) and chinning (10.70 vs 4.75 · pen−1· pen−1; P<.10) and the agonistic behavior of butting (42.42 vs 31.50 · pen−1· h−1; P<.01) in contrast to intact bulls. Castrated animals entered (P<.10) and exited (P<.05) the scales more quickly than did intact males. Zeranol implants were associated with decreased butting in intact males and increased butting in castrated males (P<.01). Serum testosterone levels were higher in implanted compared with non-implanted bulls on d 107 post-implantation (P<.01), but re-implanting tended to decrease testosterone levels (P<.10).

The diurnal behavior patterns of feedlot bulls were investigated at 52°N during winter and spring. Two trials were conducted during periods when the daylight portion of the day increased by over 7 h. In trial 1, 324 bulls were observed hourly for 24 h on nine occasions at 2-wk intervals. The average proportions of bulls eating, drinking, standing and lying were 9.8, 1.9, 27.4 and 60.0%, respectively. Major periods of eating, drinking and standing were associated with the times of sunrise and sunset and shifted with seasonal changes. Initiation and termination of the afternoon period of eating was greatly affected by changing times of sunset and not by the daily addition of feed, which always occurred at approximately 1600 h. A significant period of eating, involving up to 15% of the bulls at one time, occurred near midnight during the longer winter night but decreased in duration and intensity as day-length increased. In trial 2, continuous observations for 24 h were made at 2-wk intervals on two groups of nine bulls. When the spread in time between morning and evening activity increased due to longer daylength, bulls were active at midday. This became more pronounced on days when the photoperiod exceeded 10 h. Minor periods of activity were evident at night. Mounting and agonistic encounters increased dramatically in frequency near sunset and in general were associated with the major periods of eating and standing. Grooming occurred throughout the daylight portion of the day, and from winter to spring, scratching tended to decrease and cross-grooming to increase. Standing and agonistic activity increased on days when precipitation was recorded. During both trials, there was a period before sunrise that was notable because of the lack of activity.

Three trials were conducted involving 393 ewes to determine the feasibility of using cubicles to provide isolation for parturient ewes in lambing pens. The cubicles consisted of an enclosure with 1 m high walls and a small (.6 m wide) opening to allow ewes free access. In trial 1, 42% of the parturitions occurred in the cubicles, which occupied only 19% of the pen area. No preference was noted for large (1.8 × 1.8 m) vs small (1.8 × 1.2 m) cubicles. Use of the cubicles increased from 4% of the time 24 h before parturition to 25% of the time during the 6 h immediately preceding parturition. In trial 2, ewes did not show a preference for open vs covered walls on cubicles or for open vs covered cubicle ceilings. Cubicles were again used to a greater (P<.01) extent than would be predicted by their relative area (26% use, 18% area). In the final trial, mature ewes used cubicles to a greater (P<.10) extent than did yearlings (55 vs 38%, respectively). Cubicles and areas of the pen farthest from the working area of the herdsman were most frequently (P<.001) used during parturition. Cubicles appeared to be effective in preventing separation of newborn lambs from their dam and in reducing interference by other ewes.

A 23factorial arrangement of treatments was utilized to determine effects of postweaning zeranol implantation, breed (Angus vs Limousin) and castration (bull vs steer) on growth, behavior and carcass traits. An initial slaughter group was used to account for breed differences in composition and to determine fat and lean growth in the 9-10-11th rib section (NTE). The remaining cattle were fed a finishing diet to a fat end point of .76 cm, as determined by a backfat probe. Control bulls outgained (P<.01) control steers both to the first kill date and over the entire test and did not require significantly more time to reach the fat end point. The implant did not influence gain in bulls but did increase gain in steers. Angus and Limousins were similar in growth rate for the first 126 d before the first slaughter date. Limousins required more (P<.01) time to reach the fat end point. Bulls and Limousins produced heavier (P<.01) carcasses and larger rib eyes (P<.05; bulls; P<.01; Limousins). Steers and Angus had higher (P<.01) marbling scores and lower bone maturity. Implanting decreased (P<.05) marbling and increased carcass maturity. Small but significant shifts in carcass wholesale cut weight distribution were found between breed and sex condition groups. Bulls and Limousins had greater lean growth in the NTE. Bulls and steers were similar in fat growth, but Angus exceeded Limousin in this trait. Zeranol reduced scrotal circumference (P<.01) and testicle weight at slaughter (P<.05). Breeds were similar in final scrotal circumference, but Angus had heavier (P<.05) testicle weights. Bulls were quieter (P<.05) during weighing and mounted more frequently in the pen (P<.01) than steers. Limousins mounted more frequently than Angus and maintained larger flight distances (P<.01).

A 2 × 2 factorial experiment was conducted using growing lambs to compare single-level vs double-decked pens and high (.32 m2/lamb) vs low (.48 m2/lamb) densities. Three replicates of each treatment combination were involved using 30 lambs/pen. In the double-decked pens, an upper deck located over the rear section of the lower level provided one-third of the total floor area. Feed and water were provided on the lower level only and lambs could move freely between levels by means of a slatted ramp. All floors were of expanded metal. Use of the various areas of the pens was determined during a 24-h observation and by a videotape recording of the double-decked pens during the daylight hours. Fleece contamination was determined by visual observation and standard wool testing procedures. Gain was determined over the 8-wk period of each replicate. The high density treatment resulted in 1.5 kg/lamb (10%) less gain (P<.01) and, in the case of double-decked pens, different patterns of space utilization compared with the low density treatment. Lambs in the low density pens were able to move more successfully from resting areas to the feeding area in the afternoon (P<.01). The double-decked system did not significantly affect weight gain, but resulted in dirtier fleeces (P<.01). Approximately one-half of the lambs were never observed to use the upper deck, and these individuals had dirtier fleeces than did those that used the upper deck frequently (P<.05). It was concluded that maintaining lambs at a density of .32 m2/lamb resulted in poorer growth and that the addition of an upper deck could be an effective means of reducing density. However, double decking using expanded metal floors resulted in contaminated fleeces.

In the first of two studies on teat-seeking behavior of newborn pigs, latencies from birth to first mammary contact (LMC) and to first suckle (LS) were recorded by live observation (n = 66). LMC accounted for 66% of LS and variances were similar between these two measures, suggesting that LMC is a good predictor of time to first suckle. In a second experiment, 32 litters of pigs were farrowed in crates equipped with either solid, vertically slatted, horizontally slatted or diamond mesh creep partitions. Piglet behavior following parturition was recorded via time-lapse videotape. LMC was determined for each piglet and movements were plotted for four focal pigs/litter. Partition type did not affect LMC (mean = 34 min). LMC was significantly affected by number of littermates present during teat-seeking (P< .001), birth order (P< .001) and frequency of position changes by the sow (r = .26, P< .01). Neither sex nor birth weight affected LMC on a within-litter basis, but across litters smaller pigs had greater contact latencies (r = −.38, P< .001). Partition type did not affect distance traveled or time spent in contact with the sow, in contact with the creep partitions, free standing or the total of these. LMC was positively correlated (P< .05) with contact time with the sow (r = .34) and time behind the sow's back (r = .38) and negatively correlated with time spent free standing (r = −.35, P< .05) and in contact with the sow's rear legs (r = −.29; P< .10).