Occurrence of Intestinal Parasites and Its Impact on Growth Performance and Carcass Traits of Pigs Raised Under Near-Organic Conditions.

Parasite infection is a common problem in organic pig production, which can compromise health and growth of pigs, threaten food safety of pork products, and cause economic losses to organic farmers. To develop management strategies for controlling parasites, we evaluated intestinal parasite infection in pigs at different ages and of different sexes, and investigated whether parasite infection influences growth performance and carcass traits in a cross-sectional study. Fecal samples were collected from pigs (n = 298) raised under near-organic standards during nursery, growing, finishing, and gestating phases for analysis of fecal egg counts (FEC) of Ascaris suum, Trichuris suis, and Oesophagostomum spp. Ascaris suum eggs were not detected in the feces of nursery pigs. Eggs of Ascaris suum were found in 45%, 74%, and 0% of fecal samples of growing pigs, finishing pigs, and gestating sows, respectively, after false-positive adjustment (P < 0.001). Mean FEC of Ascaris suum was higher in infected finishing pigs than in infected growing pigs [2,502 vs. 724 eggs per gram (epg), P < 0.001]. No differences in percent of Ascaris suum positive samples or FEC of Ascaris suum were detected between sexes. Growth performance and carcass traits were not different between non-infected pigs and those infected with Ascaris suum. All pigs (n = 32) examined at slaughter had white spots on the liver, and 78% harbored Ascaris suum worms. Trichuris suis eggs were not detected in any fecal samples. Eggs of Oesophagostomum spp. were found in 7%, 0%, 1%, and 9% of fecal samples of nursery pigs, growing pigs, finishing pigs, and gestating sows, respectively, with a maximum FEC of 40 epg in all age groups. These results indicate Ascaris suum was the predominant parasite infecting growing and finishing pigs in the herds studied. To control A. suum infection, future research should investigate the efficacy of treating pigs with organically approved anthelmintics during the growing phase of production.

Utilization of Optical Flow Algorithms to Monitor Development of Tail Biting Outbreaks in Pigs.

A study was conducted to evaluate activity changes in pigs associated with the development of tail-biting outbreaks using optical flow algorithms. Pigs (n = 120; initial body weight = 25 ± 2.9 kg) housed in four pens of 30 pigs were studied for 13 weeks. Outbreaks of tail biting were registered through daily observations. Behavior of pigs in each pen was video-recorded. Three one-hour video segments, representing morning, noon, and afternoon on days 10, 7, and 3 before and during the first outbreak of tail biting were scanned at 5-min intervals to estimate time budget for lying, standing, eating, drinking, pig-directed behavior, and tail biting. The same video segments were analyzed for optical flow. Mean optical flow was higher three days before and during the tail-biting outbreak, compared to 10 days before the outbreak (p < 0.05), suggesting that pigs may increase their activity three days before tail-biting outbreaks. All optical flow measures (mean, variance, skewness, and kurtosis) were correlated (all p < 0.01) with time spent standing, indicating that movement during standing may be associated with optical flow measures. These results suggest that optical flow might be a promising tool for automatically monitoring activity changes to predict tail-biting outbreaks in pigs.

Minimal floor space allowance for gestating sows kept in pens with electronic sow feeders on fully slatted floors.

A study was conducted to evaluate the minimal floor space allowance for gestating sows group-housed in pens with electronic sow feeders (ESF). Five floor space allowances were each tested in 4 pens: 1.5 m2, 1.7 m2, 1.9 m2, 2.1 m2 per sow, and 1.5 m2 per sow with more space (2.1 m2 per sow) during the first week of mixing (2.1/1.5 m2). The floor space allowances were achieved by adjusting pen size (from 80 to 88 m2) and group size (42, 46, and 51 sows per pen). Pregnant sows (n = 928, Large White × Landrace, parity = 1 to 9) were moved to ESF pens at about 5 wk of gestation and remained in their pens until about day 109 of gestation. Sows farrowed in individual stalls and weaned their litters at about 19 d after farrowing. Sows that were rebred within 1 wk after weaning were considered to have completed the study. Performance, skin lesions, and incidence of lameness in ESF pens were monitored for all sows. Data were analyzed using the Frequency, Glimmix, and Mixed procedures of the SAS software. Floor space allowance did not affect (P = 0.18 or greater) body weight, backfat depth, or condition score in ESF pens or during the lactation period. No differences (P = 0.23 or greater) were detected in farrowing rates (95, 92, 94, 94, and 95% for 1.5, 1.7, 1.9, 2.1, and 1.5/2.1 m2, respectively), completion rates (83, 79, 80, 86, and 86%), live litter size farrowed (12.5, 12.7, 12.2, 12.3, and 12.5 pigs per litter, SE = 0.24), litter size weaned (10.4, 10.5, 10.2, 10.2, and 10.6 pigs per litter, SE = 0.22), litter weight farrowed, litter weight weaned, or wean-to-estrus interval among treatment groups. Skin lesion scores for the body and for the vulva 2 d after mixing into ESF pens and when moved from ESF pens to farrowing quarters were similar across treatment groups (P = 0.54 or greater). Incidence of lameness 2 d after mixing was higher (χ2 = 21.1, df = 4; P = 0.01) for sows allowed 2.1/1.5 m2 (9.5%) and 2.1 m2 (4.2%) than sows allowed 1.9 m2 (1.8%), 1.7 m2 (2.9%), and 1.5 m2 (1.5%), which may be associated with fighting to establish dominance hierarchy during mixing in pens with larger open areas. No difference was observed in incidence of lameness when moved from ESF pens to farrowing quarters among treatment groups. These results suggest that the minimal floor space allowance of 1.5 m2 appears to be acceptable for maintaining reproductive performance and welfare of gestating sows group-housed under conditions of the current study.

Behavioral indicators of slow growth in nursery pigs.

The objective of this study was to determine how feeder-space allowance affects behaviors of slow- and fast-growing pigs during the nursery period. Nursery pigs (n = 192; initial weight = 7.4 ± 1.6 kg) were housed in 24 pens of 8 pigs, with 12 pens provided with either a two-space feeder or a five-space feeder. Pigs were categorized as slow growers (SG) and fast growers (FG) based on adjusted market weight (SG < 105 kg; FG ≥ 105 kg). Behaviors of pigs were video-recorded during the first four days after entering the nursery and on Day 21. Eating speed was measured on 96 focal pigs when they were nine weeks old. SG spent more time at the drinker than did FG (p < .05). SG spent less time in the standing/walking posture (p < .05) in pens with five-space feeders compared with SG in pens with two-space feeders. These results suggest that providing more feeder space may benefit SG in terms of improving the welfare of these pigs.