This study utilized a modeling approach to explore the long-term effects of integrating hybrid rye into organic crop production on crop yields and water use, and rye's theoretical impact on feed and bedding self-sufficiency in organic pig production. Crop yield and water use were simulated using DSSAT models for three exploratory scenarios (R1: corn-soybean-silage followed by 3 years of alfalfa; R2: rye replaced the first year of alfalfa; and R3: rye replaced the third year of alfalfa). Potential feed and bedding requirements were estimated based on a recently completed pig feeding trial. The models predicted higher rye yields and water use in R3 than in R2 (p < 0.01), suggesting a theoretical yield benefit when rye follows alfalfa. Based on these simulations, R3 could potentially provide feed and bedding for a 38 pigs & centerdot;ha(-1)& centerdot;rotation cycle(-1), compared to a 10 pigs & centerdot;ha(-1)& centerdot;rotation cycle(-1) in R2. While these findings represent theoretical scenarios rather than validated field performance, they demonstrate the potential of crop simulations for evaluations of long-term effects of organic crop rotations on yield and water use. The results suggest that integrating hybrid rye after legumes warrants further field-scale validation as a strategy to enhance resource self-sufficiency in organic pig production.

Tail biting compromises the welfare and performance of pigs. Understanding the dynamics of this behavior is essential for developing management strategies to minimize outbreaks. We used social network analysis (SNA) to evaluate the effect of group size on tail-biting interactions among pigs and to examine differences in tail-biting network position between barrows and gilts and biters and non-biters. Pigs (n = 315, initial weight = 22.1 ± 3.76 kg) with intact tails of mixed sexes were housed in small (9 pigs/pen) or large (18 pigs/pen) pens on slatted floors for 14 wk until market weight (120.2 ± 11.47 kg). Floor and feeder space allowances were identical for pigs in both group sizes. Growth performance, tail injury, and behavior were recorded. Videos recorded the day before the first TBO were manually reviewed to document tail-biting events and identify pig roles. The top 25% of pigs responsible for the most tail-biting incidents were classified as tail-biters and the remaining pigs as non-biters. Tail-biting network metrics were calculated using RStudio. Data were analyzed using SAS. Pigs in small pens exhibited higher density, reciprocity, out- and in-degree centrality, betweenness centrality, and closeness centrality (all P < 0.05), suggesting greater direct and indirect involvement in tail-biting interactions than pigs in large pens. Gilts had higher out-degree centrality (P < 0.01), indicating they initiated more tail biting than barrows. Both sexes had similar in-degree centrality, suggesting they were bitten equally. In gilts, biters tended to have lighter final weight (P = 0.08) and lower ADG (P = 0.10) and were injured less frequently (P = 0.02) by tail biting than non-biters. In both sexes, biters and non-biters had similar in-degree centrality, suggesting that they were bitten equally. These results indicate that pigs housed in different group sizes exhibit different social structures and positions in tail-biting networks, which potentially affects tail damage. Further research should evaluate network metrics across a wider range of group sizes and during multiple TBO.

This study investigated the effect of group size on tail damage and growth performance in growing-finishing pigs with intact tails. A total of 432 pigs were housed indoors on fully-slatted floors and assigned to either small (nine pigs per pen) or large (18 pigs per pen) groups, with equal space and resource allocation per pig. No environmental enrichment was provided. From nine to 23 weeks of age, pigs were monitored weekly for tail injuries using a 5-point scale (0 = no injury, 4 = partial or total loss). The most severe score observed during each four-week period was used for analysis, and outbreaks were defined as the occurrence of one or more pigs per pen with a tail score ≥ 2. Group size did not influence average daily gain, feed intake, or feed to gain ratio. However, pigs housed in small groups experienced more frequent and severe tail injuries, including a higher proportion of removals due to tail wounds. In contrast, pigs in large groups were more likely to receive healed tail scores (score 1) or mild injuries (score 2), and experienced fewer removals. While these results suggest that tail damage may be less severe in larger groups, the total number of pigs affected by tail biting was similar across treatments. These findings highlight the importance of managing tail-damage severity and suggest that group size can influence welfare outcomes in systems where pigs are raised with intact tails.

This study evaluated the utility of winter hybrid rye as a partial replacement for corn in an organic pig production system. Winter hybrid rye replaced 50% of corn in diets for growing-finishing pigs raised organically to determine pig performance, carcass characteristics, and phosphorus concentrations in fecal samples. A total of 500 pigs (initial body weight = 18.9 ± 2.94 kg) were assigned to either a Control or Rye treatment (50 pigs/pen; 5 pens/treatment) balanced for sex and body weight. Control pigs received a corn-soybean meal diet, while Rye pigs were fed a diet where hybrid rye replaced 50% of the corn in the control diet. Pigs were housed in a hoop barn, with wheat straw bedding provided to Control pigs and rye straw bedding for Rye pigs. Pig performance, including body weight (BW), average daily gain (ADG), average daily feed intake (ADFI), and gain efficiency (G:F) were recorded every 28 days. At the end of the trial, carcass traits such as hot carcass weight (HCW), backfat thickness (BF), and loin eye area (LEA) were measured. Feed samples from each dietary phase were analyzed for nutrient composition, including phosphorus and phytic acid concentrations. Fecal samples from 80 pigs (40 Control and 40 Rye) were collected and analyzed for phosphorus and phytic acid concentration. There were no differences in BW, ADG, ADFI, G:F, or fat-free lean percent of carcass between Control and Rye fed pigs (p > 0.05). However, carcass yield and LEA were lower in Rye-fed pigs (p < 0.05). Mortality tended to be lower in Rye-fed pigs (p = 0.082) probably due to random variation, while morbidity was not different between treatments (p > 0.05). Phosphorus concentrations in Rye diets were higher across most dietary phases (p < 0.05), but there were no differences in phosphorus or phytic acid concentrations in the fecal samples between treatments suggesting improved utilization of dietary phosphorus in Rye-fed pigs. In conclusion, replacing 50% of corn with winter hybrid rye in diets for organically-raised growing-finishing pigs did not affect growth performance but reduced carcass yield.

The primary objective of this study was to evaluate effects of hybrid rye in diets for growing-finishing pigs on growth performance, carcass characteristics, and phosphorus concentrations in feces. Pigs (n = 500; initial body weight = 18.9 ± 2.94 kg) were assigned to either a Control or Rye treatment (50 pigs/pen; 5 pens/treatment) balanced for sex and body weight across treatments. Control pigs received a corn soybean meal-based diet, while Rye pigs received a diet in which winter hybrid rye (KWS Cereals LLC; Tayo variety) replaced 50% of the corn. A 5-phase feeding program was used to satisfy nutrient requirements as pigs aged. Pigs were raised under organic conditions according to the National Organic Program. Pigs were housed in a hoop barn with wheat straw bedding provided to Control pigs and rye straw provided to Rye pigs. Pig performance (BW, ADG, ADFI, and gain efficiency (G:F)) was recorded every 28 days. At the end of the trial, final BW and hot carcass weight (HCW) were recorded and backfat thickness (BF), and loin eye area (LEA) were measured using real-time ultrasonography. Data were analyzed using the Glimmix Procedure of SAS. There were no differences in overall ADG, ADFI, or G:F between Control and Rye fed pigs (P > 0.05; Table 1).Likewise, there were no significant differences between Control and Rye for final body weight, hot carcass weight, backfat depth between the 10th and 11th rib, or percent fat-free lean of carcasses (P > 0.05). However, LEA was lower in Rye-fed pigs (P < 0.05) compared with Control pigs. Mortality tended to be lower in Rye-fed pigs (P = 0.082), while morbidity was similar between treatments (P > 0.05). Phosphorus concentrations were higher in the Rye diet across most phases (P < 0.05), although no differences were observed in phosphorus or phytic acid concentrations between treatments in the fecal samples collected at harvest. In conclusion, replacing 50% of corn with hybrid rye in growing-finishing pig diets did not affect growth performance but resulted in reduced loin eye area.

Understanding the dynamics of tail biting in pigs, such as which pigs are involved and what roles these pigs play in this damaging behavior, can help us develop management strategies to minimize tail biting outbreaks. We evaluated social structures and positions of pigs involved in tail biting outbreaks (TBO) using social network analysis. Pigs (n=252, initial weight=28.9±3.4 kg) with intact tails were grouped (7 pigs/pen, 36 pens) based on litter origins (littermates, half-group littermates, non-littermates). Pigs were housed in barns with slatted floors (0.98m2/pig) for 12 weeks until market weight (123.1±11.9 kg). Behavior of pigs was recorded continuously using the NUtrack Livestock Monitoring System. Tail injury was evaluated weekly to monitor TBO. Thirteen pens (littermates=3 pens, half-littermates=5 pens, and non-littermates=5 pens) experienced TBO in which at least one pig in a pen had blood on the tail caused by tail biting. Videos for these pens, recorded the day before and during the first TBO, were manually reviewed to document tail biting events and identify the roles of the pigs involved. The top 25% of pigs responsible for the most tail-biting incidents were classified as tail-biters and others as non-biters. Network metrics were calculated using RStudio. Data were analyzed using Glimmix and NPAR1WAY procedures. No difference in network metrics at the pen-level (all P ≥ 0.128; Table 1) was detected among litter origins. Average density ranged from 0.27 to 0.33, indicating that 27 to 33% of possible pairs (dyads) of pigs engaged in tail biting. Among these pairs, 17 to 37% (reciprocity) were biting each other. Out-, in- and all-degree centralizations were closer to 0 than 1, indicating that tail biting was not performed mainly or received by few pigs. At the pig-level, no difference was detected in unweighted or weighted centralities among litter origins (all P ≥ 0.32). Compared to non-biters, tail-biters had greater unweighted out-degree, closeness, and betweenness, and greater weighted out-edge strength and betweenness centralities (all P ≤ 0.04, Table 2), indicating that tail-biters bit more pigs, were more connected to other tail-biters, and committed more tail biting events. No difference was detected in unweighted in-degree, weighted in-edge strength, out- and in-closeness centralities between tail-biters and non-biters. Both tail-biters and non-biters were bitten about 3 times (in-edge strength) by 1.76 pigs (unweighted in-degree centrality) on average, suggesting that tail-biters were bitten as often as non-biters. Gilts tended to have greater (all P ≤ 0.08) unweighted closeness and betweenness, weighted out-edge strength and betweenness centralities than barrows, suggesting that gilts were more closely connected with other pigs that were involved in tail biting and performed more tail biting than barrows. These results demonstrate that social network analysis can provide insight into the dynamics of tail biting among pigs.

The injury and stress associated with tail biting poses a welfare challenge for the swine industry. Differences in immune status may predispose pigs to tail-biting. Our aim was to evaluate whether tail-biting pigs differ from non-biters in growth performance, tail injury, and immune markers. Pigs (n = 252) with intact tails were allocated to pens (7 pigs/pen) in a conventional growing-finishing barn at 10 weeks of age based on litter origin (12 pens/treatment): littermates (all pigs in a pen from the same sow), half-littermates (half from one sow, half from another sow), and non-littermates (each pig from separate sows). Pigs remained in these pens until market weight at 22 weeks. Growth performance (initial and final body weight, and ADG) was monitored. Tail injury was assessed weekly for all pigs using a 0-4 scale (0=no injury; 1=healed injury; 2=visible blood; 3=wounds or abscesses; 4=tail loss). The greatest tail biting score each pig received during the study was defined as the Maximal Tail Score (MTS). A tail-biting outbreak (TBO) occurred when at least one pig in a pen scored ≥ 2. On the first TBO in a pen, blood samples were collected from all pigs in the TBO pen and from two pigs in a control pen with no evidence of tail biting. Serum samples were analyzed for 13-panel cytokines, immunoglobulin G (IgG), and Pig Major Acute Phase Protein (Pig-MAP). The behavior of pigs in each pen was recorded over the study period using the NUtrack Livestock Monitoring System. Of the 36 pens across litter origin treatments, 12 pens experienced a TBO. On the day of the first TBO, videos during the light period (0800 to 1500 h) were manually reviewed to identify and categorize tail-biters and non-biters. Biters were identified as the top 25% of pigs across all treatment groups that committed most tail biting. Data were analyzed using the GLIMMIX with pig as the experimental unit or Frequency Procedures with chi-square tests of SAS. Data of 13-panel cytokines, IgG, and Pig-MAP were log-transformed to achieve normal distribution. No difference in initial and final weights or ADG among biters, non-biters, and control pigs was detected (Table 1). Tail biters had elevated TNF-α concentrations compared to control pigs (P = 0.03). No difference was detected in other cytokines, IgG, or Pig-MAP among pig categories. A greater percentage of biters were gilts compared with non-biters (X² = 4.69, df = 1; P = 0.03). No differences were observed in MTS among pig categories. These findings suggest that tail-biting could be associated with an inflammatory response, as indicated by elevated TNF-α concentrations. Further research should investigate biological mechanisms driving elevated TNF-α concentrations and focus on potential relationships between inflammatory markers and tail-biting in pigs.

The objective of this study was to identify when and where tail-biting occurs and analyze pig postures to inform management strategies that reduce tail-biting and improve pig welfare. Pigs (N = 315; initial weight = 22.07 ± 3.76 kg) with intact tails were assigned to small (SG, 9 pigs/pen, 4.80 x 1.55 m) or large (LG, 18 pigs/pen, 4.80 x 3.10 m) pens, with SG having 4 feeder spaces and LG having 8 feeder spaces. Pig behavior was recorded continuously for 14 weeks using the NUtrack Livestock Monitoring System. Videos were manually viewed from 0800 to 1500 h on the day before the first tail-biting outbreak in each pen to register behavior when tail-biting occurred. Data were analyzed using the FREQ procedure in SAS. Standardized residuals (> 2 or < -2) were used to identify significant deviations in temporal distribution and feeder occupancy. Residuals of hourly tail-biting events indicated a higher-than-expected occurrence between 0800 – 0900 h (r = 3.21) and 1400 – 1500 h (r = 3.72), whereas lower-than-expected occurrences were observed between 0900 – 1000 h (r = -3.26) and 1000 – 1100 h (r = -4.36). Victimized pigs were primarily lying sternal (χ2 = 1818.06, df = 5; P < 0.0001), while pigs engaging in tail-biting were more likely to be standing compared to non-biting pigs (χ2 = 1008.6, df = 3; P < 0.0001) during tail-biting events. Tail-biting predominantly occurred in the middle of the pen rather than near the front or rear of the pen (χ2 = 24.41, df = 2; P < 0.0001). Tail-biting was more likely to occur when feeder occupancy was low, specifically when 50% or fewer of the feeder spaces were occupied, in both SG (χ² = 362.55, df = 4; P < 0.0001) and LG (χ² = 224.86, df = 8; P < 0.0001). In SG, biting was significantly overrepresented when 0 or 1 pigs were at the feeder (r = 9.70, 9.34). Pigs in LG exhibited a similar trend, with tail-biting overrepresented when 0, 1, 2, or 3 pigs were at the feeder (r = 3.0, 2.04, 6.35, 7.62). These results indicate that tail-biting occurred more frequently when victimized pigs were lying sternally in the middle of the pen during the morning and late afternoon, particularly when most feeder spaces were unoccupied. Further research is needed to validate these findings for the development of management strategies to minimize tail-biting and improve pig welfare.

Tail-biting is a persistent welfare problem in growing-finishing pigs. Identifying pigs that initiate tail-biting and understanding factors predisposing pigs to tail biting remains challenging. This study aimed to identify and characterize tail biters and compare growth, tail injury and tail biting behavior between tail biters and non-tail biters. Pigs (n = 432) with intact tails were assigned to small (9 pigs/pen) or large (18 pigs/pen) pens at 9 weeks of age and remained in the same pen until market weight at 23 weeks of age. Growth performance was measured over the 14-week study period. Tail injury was assessed weekly on all pigs using a 0-4 scale (0=no injury; 1=healed injury; 2=visible blood; 3=wounds or abscesses; and 4=tail loss). The greatest score each pig received over the study period was defined as the Maximal Tail Score (MTS). A Tail-Biting Outbreak (TBO) was confirmed when one pig in a small pen or two pigs in a large pen scored ≥ 2. Pig behavior was recorded continuously for 14 weeks using the NUtrack Livestock Monitoring System. Videos from 0800 to 1500 h on the day before the first TBO in each pen were viewed manually to record ID and sex of tail biters and victimized pigs. Tail bites per pig performed (# TB), total tail bites occurred per pen (Total TB), and tail bites per pig as a percentage of total tail bites in the pen (% Total TB = [# TB/Total TB] x 100%) were summarized using ANOVA. The top 25% of pigs in each group size for # TB and % Total TB were classified as tail biters. Tail biters in small pens performed at least six tail bites and contributed at least 20.0% of total tail bites in the pen, while tail biters in large pens were responsible for at least four tail bites and accounted for at least 10.6% of total tail bites in the pen (Table 1). Other data were analyzed using GLIMMIX Procedure with pens as the experimental unit or Frequency Procedure with Chi-square test in SAS. Initial weights did not differ between biters and non-biters; however, biters had lighter final weights (P = 0.03) and lower ADG (P = 0.02) than non-biters. Biters are predominantly gilts, accounting for 70% of the group. On average, biters were tail bitten less frequently than non-biters (P = 0.0001). No difference in MTS between biters and non-biters was detected. Results suggest that tail-biters were predominantly gilts, exhibited lower ADG and lighter final weights, and were less frequently tail-bitten than non-biters.

The production of organic meat and dairy products relies on limited organic protein meal supplies. Camelina (Camelina sativa L.) may sustainably increase organic protein meal supplies. Using grain production trial data, research literature, and camelina feeding trial results, greenhouse gas (GHG) emissions and fossil energy impacts were modeled for inclusion of 10% camelina meal in swine finishing diets using life cycle analysis (LCA). Two key grain production scenarios were examined: field trial relay (FTR) camelina and a higher yielding as expected relay (AER) camelina, with a baseline monocrop soybean (MCS). At the grain production stage, the FTR, AER, and MCS scenarios emitted 0.65, 0.43, and 0.13 kg of CO2 eq./kg DM grain harvested, respectively. At the meal production stage, 0.61, 0.40, and 0.15 kg of CO2 eq. were emitted per kg of protein meal from the FTR, AER, and MCS scenarios, respectively. GHG emissions from the finishing phase of pork production were 1.43, 1.38, and 1.31 kg CO2 eq./kg live weight pigs produced for the FTR, AER, and MCS scenarios, respectively. Findings were similar for fossil energy use. The higher environmental burdens from camelina grain production due to reduced yields of both camelina and soybean resulted in negative environmental performance in camelina-amended diets.

Among the numerous management challenges related to tail biting, identification of tail biters is near the top of the list. In this study, we evaluated the behaviors of pigs identified as tail biters and non-biters. Pigs (n=216; 9 wks of age) with intact tails were allocated to growing-finishing pens (9 pigs/pen) and video-recorded using the NUtrack system for 14 wks. Tail injuries caused by tail biting were assessed weekly using a scoring system from 0 to 4 (0 = no injury; 1 = healed injury; 2 = visible blood; 3 = wounds or abscesses; and 4 = tail loss). A pen was recorded to have a tail-biting outbreak (TBO) when any pig within a pen received a tail score ≥2. Six pens in which TBO occurred were selected to identify tail biters and used to assess differences in behaviors between tail biters and non-tail biters. To identify tail biters, NUtrack video from 0800 to 1500 h the day before the first TBO in each pen was reviewed to record all tail biting events and pigs involved. Pigs in each pen that committed the most tail bites (TB), based on the number of TB observed and % of total TB, were classified as tail biters; all remaining pigs were considered non-biters. Behaviors (meters walked/day, body revolutions/day, percent of time standing, percent of time at the feeder, percent of time lying lateral, lying sternal, sitting, total time lying, and total time resting), as determined by the NUtrack system, were analyzed using PROC GLIMMIX with repeated measures of SAS. There was no main effect (P≥0.32) for biting classification (tail biter vs. non-biters) and no interaction (P≥0.45) for biting classification by day for any of the behaviors analyzed. No difference (P≥0.44) was observed between tail biters and non-biters for meters walked/day and body revolutions/day. On average, pigs walked 810 meters/day (841 and 779 meters/day, respectively) and completed 229 revolutions/day (235 and 223 revolutions/day, respectively). There was no difference (P≥0.38) in time standing/day and time at the feeder between tail biters and non-tail biters. On average, pigs spent 11.2% of the observation time standing (11.3 and 11.1%, respectively) and 3.3% of the time at the feeder (3.3 and 3.4%, respectively). There was no difference (P=0.61) between tail biters and non-biters total time lying, spending on average 86.2% of time lying (86.4 and 86.0%, respectively). There was no difference (P=0.32) in the total time pigs spent sitting, an average of 2.6% of the time sitting (2.3 and 2.8%, respectively). Based on this limited dataset, tail biting pigs did not have altered behaviors compared to non-biters. However, increased data from ongoing studies might provide more robust insight into behavior differences between tail biters and non-biters.

Tail biting is a multifactorial behavior that causes welfare and economic challenges in swine production. As of 2024, research exploring the influence of pig social structure on the development of tail biting is limited. The objective of this study was to explore whether social structures of pigs from different litter origins can impact tail biting and, ultimately, tail damage. Pigs (n = 96) were grouped (eight pigs/pen) based on their litter origin: non-littermates (NLM), half-littermates, and littermates (LM). Tail injury scores were assessed twice weekly from 10 to 24 weeks of age, with a maximal tail injury score (MTS) over the study period being used to evaluate victimization by tail biting. Pig behavior was video-recorded at 15, 19, and 23 weeks of age. Association networks based on lying behavior and tail biting interaction networks were evaluated at pen-and pig-levels using social network analysis. Pigs in LM pens experienced higher median MTS compared to pigs in NLM pens (Median = 1.5; Interquartile range = 1–2; p = 0.009). Within association networks, NLM pens had lower degree centralization measures than other pens at both 15 (Estimated marginal mean [EMM] = 0.07; 95% CI = 0.02–0.12; p = 0.003) and 23 weeks (EMM = 0.09; 95% CI = 0.04–0.14; p = 0.01) and pigs in NLM pens had higher weighted degree centrality than those in other pens (EMM = 1.00; 95% CI = 0.90–1.11; p = 0.002), suggesting pigs in NLM pens had more uniform, stronger, and more connections with their pen-mates. In tail biting networks, increased weighted in-degree centrality was associated with increased odds of pigs receiving a more severe MTS (OR = 1.56; 95% CI = 1.08–2.27; p = 0.02). Pigs with increased weighted out-degree centrality tended to have increased odds of receiving a more severe MTS (OR = 1.19; 95% CI = 0.97–1.48; p = 0.09). These preliminary data suggest a potential relationship between social structures and tail biting in growing-finishing pigs.

Abstract In organic pig production, hybrid rye grain and straw can be used as feed and bedding, respectively, to reduce production costs. However, there is a concern that replacing corn with hybrid rye in pig diets may affect pork quality. In this study, we investigated whether inclusion of hybrid rye in pig diets can affect quality and consumer acceptability of pork from organically raised pigs. Pigs [n = 200, initial body weight (BW) = 26.8±3.5 kg, 10 wk of age] were assigned to Control or Rye treatments (50 pigs/pen; 2 pens/treatment) within a hoop barn and stratified for BW and sex across pens. Control pigs received corn, soybean meal-based diets. Rye pigs were fed diets in which hybrid rye replaced 50% of the corn in control diets. Near market BW (average = 127 kg, 22 wk of age), 8 pigs per pen (4 barrows and 4 gilts) closest to the average BW of all pigs in the pen were selected for evaluation of pork quality and consumer acceptability. Carcass pH at 45 min and 24 h postmortem in the ham, and objective color scores (L*, a*, b*), shear force, and subjective color and marbling scores were collected from a loin chop. Loin chops were kept at or below -18°C until a consumer taste panel was conducted to assess overall liking, flavor liking, texture liking, toughness, juiciness, and off-flavor of pork from the cooked loin chops. Liking ratings were made on 120-point scales (0 - strongest dislike imaginable, 120 - strongest like imaginable). Toughness, juiciness, and off-flavor were ranked on 20-point scales (0 - none, 20 - extremely tough, juicy, or intense, respectively). Data were analyzed using the Mixed procedure, Frequency procedure with chi-square test of SAS. Measures of pork quality (pH at 45 min and 24 h, a*, b*, shear force, and subjective marbling and color scores) were not different between treatments (Table 1). Pigs fed Control diets displayed a greater (P = 0.006) L* reading than Rye-fed pigs indicating that pork from Control pigs was lighter in color than Rye-fed pigs. Generally, the taste panel did not detect a difference in acceptability of pork from Control and Rye-fed pigs. Juiciness and off flavor were scored very similarly by panelists. However, pork from Rye-fed pigs tended (P = 0.075) to be tougher than pork from Control pigs. Liking attributes (overall liking, flavor liking, and texture liking) were scored similarly between Rye-fed and Control pigs and generally better than neutral (neutral=60/120) by panelists. These data suggest that replacing 50% of corn with hybrid rye in diets for growing-finishing pigs will not negatively impact quality or consumer acceptability of pork.

Abstract An obstacle to profitable organic swine production is the high cost of feed and bedding. We evaluated whether growing hybrid rye for organic feed and bedding for pigs was economically viable by replacing corn with hybrid rye and evaluating pig growth performance and feed and bedding costs. Hybrid rye was grown on certified organic land at WCROC in 2022 and 2023. Rye grain and straw were used in a feeding trial with pigs raised according to the National Organic Standards. The animal trial consisted of three replicates. Each replicate included 100 pigs in two pens (Control vs. Rye, 50 pigs/pen) in a bedded hoop barn. Control pigs were fed corn soybean meal-based diets and Rye pigs were fed diets with 50% of corn in the control diets replaced by hybrid rye. Each replicate lasted for about 12 wk until pigs reached market weight (120 kg). Pigs were weighed individually at the beginning, every 4 wk thereafter, and at the conclusion of the study. Feed disappearance was recorded on a pen basis at the time of weighing pigs. Growth performance[average daily gain(ADG), average daily daily feed intake (ADFI), and Gain: Feed] was calculated for each weigh period. Carcass weight was recorded at harvest and dressing percent was calculated for each pig. Bedding usage was recorded for each pen (Control pen = wheat straw, Rye pen = rye straw) and average usage for each pig was calculated. Growth performance and bedding usage data were analyzed using the Proc Glimmix Procedures of SAS, with dietary treatment as the fixed effect, replicate as the random effect, and pen as the experimental unit. Production costs were set at $239/ha for organic rye grain and $20/ha for rye straw baling according to the FINBIN Database, and the unit costs ($/kg) were calculated based on yield for each year. Prices for organic corn, soybean meal, base mix, wheat straw, and market pigs were based on market prices (Table 1). Yield of organic hybrid rye grain at WCROC was 1,070 and 712 kg/ha in 2022 and 2023, respectively, with corresponding rye straw yield being 661 and 367 kg/ha. The reduction in rye yield in 2023 was considered due to drought. No difference was detected in growth performance, dressing percent, or bedding usage between Control and Rye pigs (all P > 0.19; Table 1). Replacing 50% of corn with hybrid rye saved $9.6/pig in 2022, but cost $7.20/pig more for feed in 2023, due to changes in hybrid rye grain yield. Savings on bedding were $15.40 and $13.20/pig for 2022 and 2023, respectively. Results indicate that replacing 50% of corn with hybrid rye in feed did not negatively affect growth performance of pigs raised organically, but the economic viability of integrating hybrid rye into organic pig production may depend on crop yield.

Abstract Tail biting is a multifactorial phenomenon with many aspects contributing to a tail biting outbreak. Little is known about how social structures influence tail biting. Our objective was to determine if litter origin impacts growth performance and tail damage caused by biting behaviors of undocked growing-finishing pigs. Pigs were separated based on their litter origin. Three treatments (12 pens/treatment) were tested: LM = all littermates (all 7 pigs/pen were farrowed and nursed by the same sow), N = non-littermates (7 pigs/pen were farrowed and nursed by 7 different sows), and H = half-group of littermates (7 pigs/pen were farrowed and nursed by 2 sows with 3 or 4 of pigs from each sow). The study was conducted in 2 replications (6 pensּ treatment-1ּ replication-1). Within each replication growth performance, mortality, and morbidity were recorded for 12 wk until pigs reached market weight. Tail damage was evaluated using a subjective scoring system: 0 = no evidence of tail biting; 1 = evidence of chewing without visible blood; 2 = evidence of tail biting with visible blood; 3 = open wounds or abscesses with signs of infection; and 4 = partial or total loss of the tail. Tail damage was assessed weekly during the study period, and the maximal tail score (MTS) that each pig received over the entire 12 wk was recorded. The number of pigs removed and the reason for removal was recorded. Data were analyzed using the mixed procedure of SAS for performance variables with a statistical model including treatment, week, and their interaction as fixed effects, replication as a random effect, and initial body weight as a covariate. A frequency procedure with a chi-square (CMH) tested treatment effects on pigs removed and MTS. Litter origin did not affect average daily feed intake (ADFI), gain to feed ratio (G:F), or pigs removed from each treatment group (all P > 0.19; Table 1), but average daily gain (ADG) of H pigs tended to be greater than that of LM pigs (P = 0.07). Maximal tail score was influenced (P = 0.008) by litter origin treatments. Pigs in LM groups had a greater percentage of MTS 0 compared with H and N groups; and H had greater severity of tail damage with 16.7% of the pigs having an MTS of 3 or greater, while both LM and N had less than 5%. Results of this study suggest that litter origin can influence severity of tail damage caused by tail biting behaviors as indicated by MTS. Future studies should focus on the differences among litter origin treatment groups regarding social interactions to further understand how social structure influences tail biting behaviors.

This study explored whether biofumigation with rapeseed can reduce swine parasite eggs in pasture soil. Pastures were subjected to four treatments: rapeseed or Ladino clover pastures, each with or without biofumigation (i.e., mechanical incorporation of plant residues into the soil). Each pasture was split into four paddocks and eight to nine pigs were given access to each paddock for 1 week. Fecal samples ( n = 66) were collected from each pig before grazing for analysis of Ascaris suum , Trichuris suis , and Oesophagostomum spp . egg counts. Soil samples ( n = 480) were collected from each paddock before grazing, immediately after pigs were removed from paddocks, and weekly thereafter for 3 weeks for analysis of Ascaris suum and Trichuris suis egg counts. Pasture treatment did not affect egg counts of either parasite species in the soil. Eggs of A. suum and T. suis in pasture soil were reduced (both P < 0.05) 2 weeks after pigs were removed, compared to before grazing and immediately after pigs were removed. Results suggest that biofumigation was not effective in reducing swine parasite eggs in organic pasture soil under conditions of the current study, and parasite contamination was reduced 2 weeks after pigs were removed from pastures regardless of biofumigation.

Abstract Tail biting can compromise the welfare of pigs and cause economic losses for pork producers, but little is known about the development of tail biting and its resulting impact on pigs. In this study, we investigated victimization by tail biting and the resulting impacts on the welfare and performance of pigs housed in two group sizes. Pigs (n = 432, initial body weight = 22.0 ± 3.7 kg) with intact tails were housed in large (LG = 18 pigs/pen, 12 pens) or small groups (SG = 9 pigs/pen, 24 pens) in a barn with fully slatted floors for 14 wk until market weight (120.7 ± 11.8 kg). Floor space (0.76 m2/pig) and feeder space (4 feeder spaces/9 pigs) allowance were identical between group sizes, and pigs were stratified by initial body weight and sex across treatment pens. Growth performance, pig removal, and tail damage were monitored throughout the study. Tail damage was assessed for each pig weekly and during tail biting outbreaks, using a subjective scoring system (0 = no damage; 1 = healed lesions with small scabs; 2 = puncture wounds with visible blood; 3 = wounds with signs of infection; 4 = partial or total loss of the tail). The maximal tail score (MTS) each pig received every four weeks and over the entire 14 weeks was summarized. Pigs that received MTS of ≥ 2 were considered victimized by a tail biter. Data were analyzed using Glimmix procedure with logit function and FREQ procedure with chi-square and CMH test of SAS software. Compared with SG, LG had greater MTS during the initial 4 wk (1.1 vs. 0.8, chi-square = 17.9, df = 1; P < 0.001) and reduced MTS during the last 2 wk (0.7 vs. 0.9, chi-square = 4.8, df = 1; P = 0.03), suggesting that tail damage declined as pigs grew in LG, but not in SG. The number of pigs removed for tail biting tended to be less and those removed for death and sickness tended to be greater in LG than in SG (chi-square = 7.4; df = 3; P = 0.06). Across group sizes, 68% of the removed pigs (n = 28) were victimized by tail biters (MTS ≥ 2). Between group sizes, there was no difference in time to first victimization or how often individual pigs were victimized throughout the study. Across group sizes, 45% of pigs were never victimized, but 22%, 16%, and 9% were victimized 1, 2, and 3 times, respectively. Eight percent of pigs were victimized more than three times, including 6% with MTS of 3 or 4. Pigs with MTS of 4 over the entire study period were three times more likely (odds ratios between 3.18 and 3.70; all P ≤ 0.03; Table 1) to have market weight lower than the average compared with other pigs. Based on these results, we suggest that management strategies should prevent multiple victimizations or tail loss to maintain pig welfare and performance.

Tail biting is both an economic and welfare problem of grower-finishing pigs. This destructive chewing behavior of tails of pen-mates causes challenges for farmers who raise pigs with intact tails, resulting in the need to find management solutions. Our objective was to determine if group size influences growth performance and tail damage caused by biting behavior of undocked growing-finishing pigs. Pigs (n = 432; initial BW = 22 ± 3.8 kg) with intact tails were allocated to small pens or large pens on totally slatted floors, with equal ratio of barrows to gilts in each pen and balanced for average initial BW across pens. Small pens (SM; n = 24) housed 9 pigs/pen and large pens (LG; n = 12) held 18 pigs/pen. Floor space allowance (0.76 m2/pig) and feeder-space allowance (4 feeder spaces/9 pigs) were consistent across group sizes. Pigs were weighed individually and feed intake was recorded on a pen basis every 4 weeks for 16 weeks until market weight (120 kg ± 3.8 kg), from which ADG, ADFI, and Gain:Feed were calculated. Number of pigs that were dead (mortality) and removed (morbidity) from the study due to tail biting, lameness, and other health issues were recorded throughout the study period. Tail damage was evaluated using a 0 to 4 scale scoring system: 0 = no evidence of tail biting; 1 = evidence of chewing without visible blood; 2 = evidence of tail bitten with visible blood and no signs of infection; 3 = open wounds or abscesses with signs of infection; 4 = partial or total loss of the tail. Tail damage was assessed once weekly during the study period, and the maximum tail score (MTS) that each pig received over the entire 16 weeks was recorded. Data were analyzed using SAS software, with a mixed procedure for performance variables and a frequency procedure with chi-square test for mortality, morbidity, and MTS. Group size did not affect growth performance (all P > 0.70; Table 1), mortality, or morbidity (Chi-square = 2.33, df = 2; P = 0.31). However, group size affected MTS (chi-square = 10.78, df = 4; P = 0.03). Pigs in SM experienced a marginally lower prevalence of tail biting compared with LG (16% vs. 9% of pigs receiving an MTS of 0); but greater severity with 13.0% of pigs in SM vs. 7.4% of pigs in LG receiving an MTS of 4. These results suggest group size did not influence growth performance, mortality, or morbidity; but affect severity of tail damage caused by tail biting. Compared with LG, SM had more pigs that lost their tails due to tail biting, which seriously compromised pig welfare.

Nodular roundworms (Oesophagostomum spp.) are frequent parasites of the large intestine in several mammal species including humans and pigs, and their study often requires the use of infective larvae produced using several coproculture techniques. However, there is no published comparison of techniques to determine which yields the highest number of larvae. This study compares the number of larvae recovered from coprocultures made with charcoal, sawdust, vermiculite, and water in an experiment repeated twice using feces from a sow naturally infected with Oesophagostomum spp. at an organic farm. A higher number of larvae were recovered from coprocultures using sawdust relative to other types of media used, and this was consistent across the two trials. The use of sawdust to culture Oesophagostomum spp. larvae is rarely reported and our study suggests it can yield higher numbers relative to other media.

Parasite infection is a common problem in organic pig production. Pastures grazed by infected pigs can become sources of parasite transmission because parasite eggs can survive in soil for several years. Biofumigation is a method used by farmers to reduce plant pathogens and nematodes in soil by incorporating plant residues into the soil that rapidly release toxic isothiocyanates. This study explored whether grazing crops with biofumigation properties affects parasite fecal egg counts of pigs managed organically, and subsequent parasite eggs in organic pasture soil after biofumigation. A study was conducted using 66 pigs (BW = 72.6 kg ± 21.2 SD) that were raised organically in two blocks. Within each block, pigs were housed in four pens (8 to 9 pigs/pen) and provided feed ad libitum in a hoop barn. Each pen had access to a pasture (0.5 acres). Each pasture was subjected to one of four management treatments: control pastures (Ladino clover) or biofumigation pastures (Rapeseed), each with or without incorporating plant residues. Each pasture was split into four paddocks (9.1m × 10.7m) and pigs were given access to each paddock for one week. Fecal samples (n = 198) were collected from each pig before, two and four weeks after grazing. Triple soil samples (n = 480) were collected from each paddock before grazing, immediately after pigs were removed from pasture paddocks, and weekly thereafter for three weeks. Fecal and soil samples were analyzed for Ascaris suum, Trichuris suis, and Oesphagostomum spp. eggs. Data were analyzed using a mixed model with pen or paddock as the experimental unit. Fecal egg counts of the three parasite species did not differ between pigs that grazed on pastures with different management treatments. All pigs had drecreased Ascaris suum (P < 0.01) and Trichuris suis (P < 0.01) fecal egg counts after four weeks of grazing compared with before grazing. Both clover and rapeseed pastures without incorporating plant residue had decreased Ascaris suum egg counts in the soil compared with incorporating plant residue (both P < 0.05). Rapeseed pastures without incorporating plant residue had reduced (P < 0.05) Trichuris suis egg counts in the soil compared with clover pastures but did not differ from rapeseed pasture with incorporated plant residue. Across pasture management treatments, Ascaris suum and Trichuris suis eggs in the soil were reduced (P < 0.05) two and three weeks after pigs were removed from pastures compared with before, immediately after, and one week after pigs were removed. These results suggest that grazing pastures crops with biofumigation properties did not affect fecal egg counts of pigs. While the number of parasite eggs decreased overtime in pasture soil, biofumigation may not be an effective way to reduce swine parasite eggs in organic pastures.