Developing effective enrichments is important for improving pig (Sus scrofa) welfare as it increases species-specific behaviours, decreases abnormal behaviours, and increases time active. However, few enrichments are available for sows in farrowing crates. Pigs are often observed to scratch, or rub against objects, however enrichments designed to provide a scratching outlet have never been tested in sows.We examined the behaviour and welfare of sows in farrowing crates when they were presented with one of two types of scratchpad enrichment. Sows (n = 18) of parities two (P2) and three (P3) were housed for 25 days and assigned no enrichment (Control) or a scratch-pad made of plastic mats (Plastic) or coir fibre mats (Fibre). Parity two Plastic sows scratched for a longer total duration than P2 and P3 Fibre sows, P3 Plastic sows, and P2 Control sows. Parity two Plastic sows also displayed scratching bouts more frequently than all except P3 Control sows. There were no body lesion differences between treatments. Abnormal behaviour and proportion of time spent in different postures also did not differ between treatments. Plastic scratch-pads may be a suitable enrichment for farrowing crates as they increased the natural behaviour of scratching. More research is needed to refine the scratch-pad design and measure motivation before it can be concluded that scratch-pads are a successful enrichment that should be implemented on-farm.

The purpose of this study was to evaluate whether linear and non-linear measures of heart rate variability (HRV) could be used as indicators of piglet castration pain. Thirty piglets were allocated to I of 4 treatments: i) sham castrated HRV (SHRV; n = 8); ii) surgical castrated HRV (CHRV; n = 7); iii) sham castrated blood collection (SBC; n = 7); or iv) surgical castrated blood collection (CBC; n = 8). Piglets in the SHRV and CHRV treatment groups underwent a I-h HRV and postural behaviour evaluation on day - day 0 (castration treatment), day I and day 3 of the experimental procedure. Piglets in the SBC and CBC groups underwent blood collection for serum cortisol analysis at -0.5, 1, 2, 3, 24, 48 and 72 h relative to castration treatment. Castrated piglets (CHRV) exhibited greater low to high frequency ratio, lower sample entropy and greater percent determinism compared to SHRV piglets, indicating greater pain-related stress due to the surgical castration procedure. Serum cortisol was greater in CBC pigs at I h post castration compared to SBC piglets. No effect of treatment was found for amount of time spent lying post-castration. In conclusion, surgically castrated pigs exhibited greater pain-related stress than their sham castrated counterparts. Additionally, non-linear HRV measures seem to complement traditional linear HRV measures and may be valuable for assessing pain-related stress in future studies investigating swine welfare.

The purpose of this study was to evaluate whether pain-related stress caused by disbudding could be detected using nonlinear measures of heart rate variability (HRV). Twenty-five female Holstein calves (4-7 wk of age) were randomly assigned to 1 of 3 treatments: (1) sham disbud (SHAM; n = 9), (2) disbud with lidocaine-meloxicam pain mitigation (MED; n = 8), or (3) disbud without pain mitigation (NoMED; n = 8). Heart rate variability (sample entropy, percentage determinism, percentage recurrence, or mean length of diagonal lines in a recurrence plot) was recorded on d -1, 0, 1, 3, and 5 relative to the experimental procedure, with disbudding taking place on d 0. The short-term detrended fluctuation analysis scaling exponent was greater in MED calves than in SHAM calves, indicating a greater stress response to the disbudding procedure regardless of pain mitigation. These results indicate that calves in the MED group may have experienced pain-related stress as a result of the disbudding procedure. The remaining nonlinear HRV measures did not differ by treatment. Future research on this topic should address additional potential confounding factors, such as the effect of pain-mitigating drugs on autonomic function or the influence of the autonomic nervous system on wound healing, that may prohibit HRV measurement as an indicator of disbudding pain severity.

Heart rate variability (HRV) is a proxy measure of autonomic function and can be used as an indicator of swine stress. While traditional linear measures are used to distinguish between stressed and unstressed treatments, inclusion of nonlinear HRV measures that evaluate data structure and organization shows promise for improving HRV interpretation. The objective of this study was to evaluate the inclusion of nonlinear HRV measures in response to an acute heat episode. Twenty 12- to 14-week-old growing pigs were individually housed for 7 days and acclimated to thermoneutral conditions (20.35°C ± 0.01°C; 67.6% ± 0.2% RH) before undergoing one of the two treatments: (1) thermoneutral control (TN; n = 10 pigs) or (2) acute heat stress (HS; n = 10 pigs; 32.6°C ± 0.1°C; 26.2% ± 0.1% RH). In Phase 1 of the experimental procedure (P1; 60 min), pigs underwent a baseline HRV measurement period in thermoneutral conditions before treatment [Phase 2; P2; 60 min once gastrointestinal temperature (Tg ) reached 40.6°C], where HS pigs were exposed to heated conditions and TN pigs remained in thermoneutral conditions. After P2, all pigs were moved back to thermoneutral conditions (Phase 3; P3; 60 min). During each phase, Tg data were collected every 5 min and behavioural data were collected to evaluate the amount of time each pig spent in an active posture. Additionally, linear (time and frequency domain) and nonlinear [sample entropy (SampEn), de-trended fluctuation analysis, percentage recurrence, percentage determinism (%DET), mean diagonal line length in a recurrence plot] HRV measures were quantified. Heat stressed pigs exhibited greater Tg (P = 0.002) and spent less time in an active posture compared to TN pigs during P2 (P = 0.0003). Additionally, low frequency to high frequency ratio was greater in HS pigs during P3 compared to TN pigs (P = 0.02). SampEn was reduced in HS pigs during P2 (P = 0.01) and P3 (P = 0.03) compared to TN pigs. Heat stressed pigs exhibited greater %DET during P3 (P = 0.03) and tended to have greater %DET (P = 0.09) during P2 than TN pigs. No differences between treatments were detected for the remaining HRV measures. In conclusion, linear HRV measures were largely unchanged during P2. However, changes to SampEn and %DET suggest increased heat stress as a result of the acute heat episode. Future work should continue to evaluate the benefits of including nonlinear HRV measures in HRV analysis of swine heat stress.

Although a great amount of effort over the years has been spent to address critical challenges to animal welfare, many problems have resisted resolution. The reasons for this lack of success are multifaceted, involving cultural norms, absolute numbers of animals required to feed the population, government regulation, economic return on investments, biological limitations, housing requirements for large populations of animals, and sacrifices due to tradeoffs between competing attributes. In a perfect world, most challenges to animal welfare could be solved so that fewer animals suffer. Thus, identifying specific constraints in the system that cause a compromise of welfare could help to improve it, however, it could also clarify why welfare in these systems will not be improved. Some solutions initially appear to be very simple, for instance giving analgesics to animals experiencing pain. The technology is there, however, the feasibility, legal authority, and economic ability are not. If these hurdles could be removed then the welfare implications of practices like castration, disbudding, beak trimming, and tail docking could be resolved. Other challenges, such as the euthanasia of male layer chicks, will need breakthroughs in technology and implementation. And in this case, the realization that euthanasia of these animals is typically not a welfare problem, rather an ethical one is an important distinction. Some Challenges, such as environmental heat and cold stress, seem beyond our ability to solve. However, progress is being made through genetic and physiologic manipulations, and engineering innovations which may all prove to be significant achievements. Key Words:

To determine the effect of age at grouping on behavior, health, and production of dairy bull calves, 90 Holstein-Friesian bull calves were housed in individual pens until moved to 1 of 3 treatments. Calves were housed in groups of 3 calves at 3 d old (GH3), 7 d old (GH7), or 14 d old (G.H.14) until 7 wk of age. Ten groups of 3 calves for each treatment were used, with 5 pens/ treatment in each of 2 replications (10 pens/treatment, 3 treatments, 3 calves/treatment ; 90 calves total). Direct behavioral observations using instantaneous scan sampling every 10 min were conducted twice per week for 7 wk. At the same times, video data were recorded for continuous observations at feeding time to observe the overall activity of group-housed calves. Hip height, heart girth, and health scores were recorded weekly and body weight was recorded at the start and end of the study. Calves in GH3 spent more time playing and but more time cross-sucking and displacing other calves from milk bottles. Calves engaged in social interaction as early as 3 d of age, and social interactions between 3 to 6 wk of age increased markedly. Calves housed in GH14 vocalized more than did calves in GH7 and GH3. No difference was found between treatments in growth performance. Calf fecal, cough, and nasal and ocular discharge scores, differential leukocyte counts, and plasma cortisol concentrations were not affected by age at grouping. However, during the first week of grouping, when calves were moved from individual pens to group pens, some calves were unable to find their milk bottles and required guidance. In conclusion, these data show no adverse effects on health or performance and some benefits on social behavior for early (d 3) grouping of calves.

Opportunity exists to improve the efficiency of feed utilization to reduce cost of production and environmental impact on a per head basis. Focus has been placed on utilizing residual feed intake (RFI) to measure animal efficiency utilizing feeding systems that determine individual feed intake of group housed animals. Our goal was to identify biological traits that might serve as proxies for RFI to allow selection of efficient animals for those without the technology to measure RFI. Heart rate has been found to be highly related to RFI. Understanding other biological measures that are related to RFI may help refine selection practices. We utilized the data from 93 Angus bulls during Summer 2016 that were started on an 85 day performance test between 215 and 315 days of age and RFI was determined for the test period utilizing the GROWSAFE system. Pre-test and mid-test physiological (cortisol), immunological (neutrophil/lymphocyte and vaccine antibody titer) and behavioral (temperament) measures were assessed. At mid-test, RFI was negatively associated with antibody titer for bovine respiratory syncytial virus (r = -0.22, p = 0.04) and the ratio of neutrophils to lymphocytes (r = -0.22, p = 0.04). At mid-test, RFI was positively associated with the extent of activity when the animal was isolated in a pen for 30 secs (r = 0.23, p = 0.04). ADG was negatively associated with cortisol at mid-test (r = -0.27, p = 0.01). Dry matter intake was negatively associated with antibody titer for bovine respiratory syncytial virus both pre- (r = -0.33, p = 0.002) and mid-test (r = -0.32, p = 0.003) as well as neutrophil to lymphocyte ratio mid-test (r = -0.28, p = 0.01). The weight achieved by the end of the test was positively associated with the ratio of neutrophils to lymphocytes (r = 0.22, p = 0.04) and negatively associated with cortisol pre-test (r = -0.30, p = 0.004), total activity when isolated with an observer pre- and mid-test (r = -0.29, p = 0.006 and r = -0.28, p = 0.01) and the distance the observer was able to approach the animal (r = -0.29, p = 0.007). Animal efficiency, as measured by RFI was related to measures of reduced stress (cortisol and neutrophil to lymphocyte ratio) and calmer temperament. Growth rate was inversely related to mid-test cortisol and the final weight achieved was inversely related to pre-test cortisol and measures of fearfulness.

Transportation is known to be a multi-faceted stressor, with the process of loading being one of the most significant factors impacting the stress to which animals are exposed. This project was designed to determine if using a conveyor to load pigs into the top deck of a simulated straight deck trailer could lower the stress to which pigs and handlers are exposed. Pigs were assigned to either a Control group that were herded up a stationary conveyor ramp into a top deck trailer (2.5 m above the ground); or Conveyor group which were herded onto a mobile conveyor into a top deck trailer. The conveyor was 7.6 m long, 0.9 m wide and rose to 2.5 m high at a 16° slope, and moved 11.3 m/min. Two age groups were tested; Weanling pigs which were moved in groups of 20 (n = 14 groups/treatment) and Nursery pigs which were moved in groups of 10 (n = 15 groups/treatment). Behavior was recorded during loading, including slips and falls, vocalizations, assists, and time to load. Heart rate of 2 sentinel pigs/group and the handler were recorded during loading, and body temperature of the handler after loading. Pigs were held in the simulated trailer for 30 min while heart rate was recorded. After which, they were unloaded and held in a holding pen for an additional 30 min while heart rate was recorded. There were no treatment differences for slips or falls (P < 0.90). Vocalizations were too few to analyze. Both Weanling (2.8 ± 0.7) and Nursery (1.6 ± 0.5) Conveyor pigs needed to be assisted onto the conveyor more than Weanling (1.2 ± 0.4) and Nursery (0.3 ± 0.1) Control pigs (P < 0.06). There was no difference in total loading time between the treatments for any age group (P < 0.15), with Weanling and Nursery pigs loading in 50 to 45 s, respectively. There were no treatment differences for heart rate variability measures (P > 0.10). However, loading increased heart rate of Nursery pigs (204.9 ± 5.7 bpm, P < 0.005), but not Weanling pigs (172.1 ± 9.0 bpm). Nursery pigs had a greater ratio of low frequency to high frequency power during loading (P < 0.02) compared to other phases of the procedure in both Control and Conveyor groups. Heart rate (93.9 ± 1.9 bpm) and body temperature (31.1 ± 0.3°C, eye temperature) of the handler was not affected by treatment (P < 0.26). Based on behavior and physiology, the pigs had similar experiences in both treatments. This study shows that it is feasible to use a conveyor to load pigs, but it may not be advantageous.

Study objectives were to evaluate the effects of post-weaning transport during heat stress (HS) and thermoneutral (TN) conditions when dietary antibiotics are removed or replaced with a nutraceutical. Sixty mixed sex piglets from 10 sows ( = 6 piglets/sow) were weaned (18.8 ± 0.8 d of age) and then herded up ramps into 1 of 2 simulated transport trailers in either TN (28.8 ± 0.2°C) or HS (cyclical 32 to 37°C) conditions where they remained for 12 h. During the 12 h of simulated transport, fans were used to simulate air movement through the trailer, feed and water were withheld, and rectal temperature (T) was measured hourly. Following the 12 h simulated transport, piglets were unloaded from the trailer, weighed, and then housed individually in TN conditions [28.5 ± 0.1°C; 29.1 ± 0.1% relative humidity (RH)] and assigned to 1 of 3 dietary treatments balanced by weaning weight, sex, sow, and transport environment. Treatments were dietary antibiotics [A; = 20 piglets; 5.5 ± 0.2 kg BW; chlortetracycline (400 g/ton) + tiamulin (35 g/ton)], no dietary antibiotics (NA; = 20 piglets; 5.6 ± 0.2 kg BW), or 0.20% L-glutamine (GLU; = 20 piglets; 5.6 ± 0.2 kg BW) fed for 14 d. During the diet treatment period, feed intake (FI), BW, and behaviors were monitored daily. At the conclusion of the diet treatment period, all piglets were euthanized and intestinal samples were collected for histology. The T and post-transport BW loss were increased in HS (40.7°C and 0.43 kg, respectively) compared to TN-exposed (39.2°C and 0.27 kg, respectively) piglets during simulated transport. Throughout the 14 d dietary treatment phase, FI was greater overall ( < 0.01; 60.3%) in GLU compared to A and NA pigs, and tended to be greater (37.7%) in A compared to NA pigs. BW was greater overall ( < 0.01; 8.7%) in GLU and A compared to NA pigs, but no differences were detected between A and GLU pigs. Lying behavior was greater ( = 0.05; 11.7%) in NA compared to A and GLU piglets in the first 2 d following simulated transport. The villus height to crypt depth ratio was greater ( < 0.05) in the duodenum (12.1%) and jejunum (12.8%) for A and GLU compared to NA pigs, and greater in the ileum (15.6%) for GLU compared to A and NA pigs. In summary, withholding dietary antibiotics after weaning and transport can negatively affect piglet productivity and measures of intestinal morphology compared to dietary antibiotic administration and L-glutamine provision.

Recently, our lab determined that supplementing nursery diets with 0.20% l-glutamine improved health and productivity of weaned and transported piglets in a controlled environment. Therefore, study objectives were to determine the impact of replacing dietary antibiotics with 0.20% l-glutamine on growth performance and health status of piglets following weaning and transport in a production environment during the hot summer months. In July 2016, 246 mixed sex piglets (5.64 ± 0.37 kg BW; Duroc × [Landrace × Yorkshire]) were weaned (19 d of age), loaded onto a trailer, and transported for 12 h. During transport, ambient temperature (28.5 ± 0.3°C) and relative humidity (61.6 ± 1.1%) in the trailer were monitored in 5-min intervals, feed and water were withheld, and intra-abdominal temperature of 6 sentinel piglets was monitored every 10 min (39.7 ± 0.1°C). Following transport, 240 piglets were unloaded, blocked by BW, and randomly allotted to 1 of 3 dietary treatments (n = 10 pens/treatment [8 piglets/pen]). Treatments were dietary antibiotics (AB; chlortetracycline [441 mg/kg] + tiamulin [38.6 mg/kg]), no dietary antibiotics (NA), or 0.20% l-glutamine (GLU) fed for 14 d (Period 1). Following Period 1, all pigs were provided a common antibiotic-free diet until d 34 (Period 2). Data were analyzed using PROC MIXED in SAS 9.4. In Period 1, ADG tended to be greater (P = 0.06) in AB pigs (234 ± 11 g/d) compared with NA pigs (194 ± 11 g/d), with GLU pigs (213.0 ± 11 g/d) being intermediate and not different from AB and NA pigs. During Period 2, ADG increased (P = 0.03) in AB pigs (455 ± 9 g/d) versus NA pigs (420 ± 9 g/d); however, no differences were observed in GLU pigs (443 ± 9 g/d) compared with AB and NA pigs. Overall, AB and GLU increased ADG (P < 0.01; 359 ± 8 g/d) compared with NA (329 ± 8 g/d), but no differences were detected between AB and GLU pigs. Feed efficiency was improved overall (P = 0.03) for AB piglets (681 ± 13) compared with NA piglets (633 ± 13); however, no G:F difference was detected for GLU pigs (647 ± 13) versus AB and NA pigs. No ADFI differences (P > 0.11; 538 ± 13.1 g/d) were detected. Treatments for enteric challenges were greater overall (P = 0.02) in NA piglets (4.9 ± 1.5%) compared with GLU (1.5 ± 1.5%) and AB piglets (1.5 ± 1.5%). In conclusion, 0.20% l-glutamine supplementation improved piglet health and productivity similarly to dietary antibiotics following weaning and transport during the summer.

Feed withdrawal and transport commonly occur together in pigs. Objectives of this study were to determine if these preslaughter stressors, feed withdrawal and transportation, affect the levels of , stress hormone concentrations, and immune functions in infected market pigs. A 2 × 2 factorial analysis of a randomized complete block design with feed withdrawal and transport as fixed effects was used. Sixty market-weight pigs were individually inoculated with serovar Typhimurium. The experiment was replicated 3 times (blocking factor) with 20 pigs per replicate. Three days after inoculation, the pigs were randomly assigned to 1 of 4 treatments (5 pigs per treatment in each/replicate), including 1) control (Control; or no stress), 2) feed withdrawal for 12 h (FW), 3) transportation for 2 h (T), and 4) feed withdrawal for 12 h followed by transportation for 2 h (FWT). Feed withdrawal by itself or followed by transportation caused an increase of levels in ileal contents ( < 0.05), whereas only FWT caused an increase of levels in cecal contents ( < 0.05). Rectal contents (feces) consistently contained very low levels of , with no difference among treatments ( > 0.10). Cortisol increased in pigs from all 3 stress treatments ( < 0.001), with T and FWT pigs having greater concentrations than Control pigs ( < 0.05), although total white blood cell counts were lower for FWT pigs compared with Controls ( > 0.03). Each granulocyte percentage (neutrophil, eosinophils, and basophils) increased ( < 0.05) following transport but was attenuated ( > 0.05) by feed withdrawal with transport. Lymphocytes were suppressed ( < 0.05) by all stressors, and the greatest suppression occurred when pigs were transported (T and FWT). However, monocytes were suppressed ( < 0.05) compared with Controls only by FWT. Expression of IL-1 (produced by monocytes/macrophages) from the spleen cells increased ( < 0.05) with FW compared with Controls, whereas its receptor antagonist was suppressed by FWT ( < 0.05). It is concluded that some typical preslaughter practices, such as feed withdrawal and transportation, lead to greater intestinal levels and gut-associated lymphoid tissue markers of inflammation in market pigs and, consequently, to an increased food safety risk.

Sow lameness accounts for approximately 15% of culling, resulting in a decrease in productivity and welfare. Previous research in our laboratory has shown a high incidence of osteochondritic lesions in young sows. We hypothesized that decreasing the growth rate of sows would allow for proper formation of articular cartilage. The objectives of this study were to (1) quantify behavioral changes associated with the diet, and (2) prevent the development of osteochondritic lesions. Therefore, 70-d old gilts were placed on either a control diet (CON; n = 23) or a low energy diet (LOW; n = 24). The CON diet contained 3427 Kcal/kg ME. The LOW diet utilized wheat middling and soy hulls, and contained 2643 Kcal/kg ME, targeting 65 to 70% of growth. Both diets were available ad libitum from d 70 to 182. Gilts were fed LOW or CON diets in four 28 d phases, and were weighed at diet changes to calculate ADG and ADFI, which were 0.80 and 0.92 kg, respectively, for CON gilts and 0.61 and 1.06 kg, respectively, for LOW gilts. A G:F of 1.15 resulted for CON and 1.73 for LOW gilts. Behavioral observations were recorded monthly and included posture, activity, agonistic behavior, and vices. Joint samples were taken (CON = 9; LOW = 10) between d 182 to 361 and analyzed for damage. Joints were evaluated for number of lesions, lesion size, and received an articular cartilage score from 0 to 4, with 0 representing healthy cartilage and 4 representing severely lesioned cartilage. The LOW gilts spent more time standing (P < 0.01), sitting (P < 0.01), and feeding (P < 0.01). Overall, diet did not alter sham chewing (P = 0.76), nosing (P = 0.11), or tail biting (P = 0.36). Both LOW and CON gilts did not differ in the number of fights (P = 0.67); however, CON gilts spent less time fighting than LOW gilts (P < 0.01). Energy restricted feed did not decrease the lesion size or prevalence of lesions (P > 0.10). Older gilts had larger lesions on the proximal humerus (P < 0.01) and femur (P < 0.01) and the distal humerus (P < 0.03) and femur (P < 0.04) than younger gilts. An energy restricted diet is not a suitable solution to decrease fighting or to improve joint health in young sows.

Aggression during mixing of pregnant sows impacts sow welfare and productivity. The aim of this study was to increase satiety and reduce aggression by including dietary fiber and fermentable carbohydrates. Sows were housed in individual stalls 7 to 14 d after breeding (moving day was considered d 0 of treatment) and were fed (at 0700 h) with a CONTROL (corn-soybean meal based with no additional fiber sources), RSTARCH (10.8% resistant starch), BEETPULP (27.2% sugar beet pulp), SOYHULLS (19.1% soybean hulls), or INCSOY (14.05% soybean hulls) for 21 d (5 sows/diet x 5 diets x 8 replications = 200 sows). The CONTROL diet was targeted to contain 185 g(d.sow) NDF and the other diets were targeted to contain 350 g(d sow) NDF. The INCSOY diet was fed at 2.2 kg/(d.sow) and the other diets were fed at 2 kg(d sow). On d 22, sows were mixed in groups of 5 (at 1200 h). Behaviors in stalls (on d 1, 7, 14, and 21) and after mixing (d 22 and 23), heart rate (on d 1, 7, 14, and 21), blood metabolites (on d 2, 8, 15, 22, and 25), and the effects of diets on production were collected and analyzed. Sows stood more (P < 0.01) and rested less (P < 0.001) over time irrespective of the diet. Sows on BEETPULP stood more (P < 0.01) and sows on SOYHULLS rested more (P < 0.01). Sham chewing increased over days irrespective of the diet. Chewing behavior (bar and feeder) increased with days on diet (P < 0.001) and was lowest in sows on the SOYHULLS diet (P = 0.045). When mixed, biting frequency in the first hour was highest for sows on the CONTROL diet (236.5 +/- 62.6) and lowest for sows on the RSTARCH diet (90.5 +/- 30.5). Skin lesions increased (P < 0.001) 24 h after mixing sows irrespective of diet. Blood urea nitrogen (BUN) concentration was lowest in sows fed BEETPULP and SOYHULLS (P < 0.001). Serum glucose concentration was highest in sows fed RSTARCH and BEETPULP (P = 0.04), but there was no day effect (P = 0.62) or diet x day interaction (P = 0.60). The NEFA was greatest in sows fed RSTARCH, BEETPULP, and SOYHULLS (P < 0.001). Lactate (P < 0.001) and BUN concentrations were greatest on d 2 but dropped and remained constant after d 8. Average heart rate was lowest for sows on SOYHULLS and INCSOY compared with sows on the other diets (P = 0.03). Number of piglets born and average weaning weight were not affected by diets (P > 0.05). Average birth weight was lowest in the INCSOY diet (P = 0.02). This study demonstrates that RSTARCH and SOYHULLS can improve the welfare of sows by reducing aggression and increasing satiety in limit-fed pregnant sows without affecting production.

Identifying new methods of assessing livestock welfare is a growing area of research. Non-invasive methods such as infrared thermography are valuable for quick and accurate observations and could be utilized to monitor the thermal status of swine without direct contact. The study objective was to determine if infrared thermography could be used as a non-invasive, hands-off approach to accurately monitor the welfare of swine by comparing changes in skin surface temperature (SST), core body temperature (CBT), behavior, and heart rate during acute heat stress (AHS) and subsequent recovery in thermoneutral (TN) conditions. In eight replications, 16 pigs (n=8 barrows and 8 gilts) were subjected to AHS (39.3±0.1°C) for 30min followed by TN (20.6±0.1°C) for 30min. The SST, CBT, heart rate, and behavioral data were recorded throughout the entire experiment. During pre-treatment, ear base SST was greater (P<0.01; 35.6±0.3°C) than all other locations. The SST at all locations increased (P<0.01) linearly with duration of AHS exposure. During TN, maximum CBT was greater (P<0.01; 40.6±0.1°C) compared to during AHS (40.3±0.1°C). Pigs spent more time standing during AHS (P<0.01) and tended (P=0.10) to lie more during TN; however, heart rate (141±2.3 beats per minute) was not affected by treatment or duration. In summary, rapid TN exposure after an AHS challenge reduces SST; however, CBT was actually increased and this may have implications towards reduced activity and increased organ damage.

In some parts of the world, the laboratory pig (Sus scrofa) is often housed in individual, sterile housing which may impose stress. Our objectives were to determine the effects of isolation and enrichment on pigs housed within the PigTurn (R) - a novel penning system with automated blood sampling and to investigate tear staining as a novel welfare indicator. Twenty Yorkshire x Landrace weaner pigs were randomly assigned to one of four treatments in a 2 x 2 factorial combination of enrichment (non-enriched [NE] or enriched [E]) and isolation (visually isolated [I] or able to see another pig [NI]). Pigs were catheterised and placed into the PigTurns (R) 48 h post recovery. Blood was collected automatically twice daily to determine white blood cell (WBC) differential counts and assayed for cortisol. Photographs of the eyes were taken daily and tear staining was quantified using a 0-5 scoring scale and Image-J software to measure stain area and perimeter. Behaviour was video recorded and scan sampled to determine time budgets. Data were analysed as an REML using the MIXED procedure of SAS. Enrichment tended to increase proportion of time standing and lying laterally and decrease plasma cortisol, tear-stain area and perimeter. There was a significant isolation by enrichment interaction. Enrichment given to pigs housed in isolation had no effect on plasma cortisol, but greatly reduced it in non-isolated pigs. Tear-staining area and perimeter were highest in the NE-I treatment compared to the other three treatments. Eosinophil count was highest in the E-NI treatment and lowest in the NE-I treatment. The results suggest that in the absence of enrichment, being able to see another animal but not interact may be frustrating. The combination of no enrichment and isolation maximally impacted tear staining and eosinophil numbers. However, appropriate enrichment coupled with proximity of another pig would appear to improve welfare.

Chronic stressors are a major health and well-being issue in animals. Immune status of animals under chronic stress is compromised, thus reducing disease resistance and compromising well-being of the animal. The objective of this study was to determine the influence of group size of veal calves on immune status and leukocyte mRNA expression of acute phase cytokines, toll-like receptor 4 (TLR4) and tachykinin 1 (TAC1) over a five-month finishing period. Holstein bull calves (n=168), 44±3 days of age were assigned to one of three treatments; 2, 4, or 8calves/pen (pen space allowance of 1.82m2/calf). Jugular blood samples were collected at the day of grouping and then monthly for 4 months. The differential leukocyte counts were determined and mRNA was extracted from the leukocytes. Reverse transcription-qPCR was used to measure the gene expression of interleukin-1 (IL-1β), IL-1 receptor antagonist (IL-1Ra), tumor necrosis factor (TNF-α), TLR4, and TAC1 in leukocytes. Health was evaluated before grouping and monthly for 4 months. On the 1st month after grouping, veal calves that were housed in groups of 8 have greater expression of IL-1β mRNA than calves housed in groups of 4 or 2 (treatment×month, P=0.04). Also at 1 month, groups of 8 had greater TAC1 expression (P<0.05) than calves housed in groups of 4 or 2. However, the expression of IL-1Ra, TNF-α, and TLR4 were not influenced by group size. In the first month of the trial, calves in groups of 8 coughed more (P<0.05) than calves in groups of 2 and coughed more than calves in groups of 4 and 2 during the 2nd month (treatment×month, P=0.03). Calves housed in groups of 8 tended to have greater neutrophil percentage (P=0.09), neutrophil to lymphocyte ratio (P=0.06), and had lower lymphocyte percentage (P=0.06) than those housed in groups of 4 or 2. In conclusion, the number of veal calves in a group, given the same space during the finishing period did not alter IL-1Ra, TNF-α, and TLR4 mRNA expression. However, housing of calves in groups of 8 was associated with greater expression of IL-1β and TAC1 mRNA in peripheral blood leukocytes, and coughing during the first 2 months after grouping. Therefore, housing of veal calves in larger groups may lead to greater susceptibility to respiratory disease and stress.

Improving piglet survivability rates is of high priority for swine production as well as for piglet well-being. Dysfunction in the serotonin (5-HT) system has been associated with growth deficiencies, infant mortalities, or failure to thrive in human infants. The aim of this research was to determine if a relationship exists between infant mortality and failure to thrive (or unthriftiness), and umbilical 5-HT concentration in piglets. Umbilical blood was collected from a total of 60 piglets from 15 litters for analysis of 5-HT and tryptophan (Trp; the AA precursor to 5-HT) concentrations. Behavior was scan sampled for the first 2 days after birth. Brain samples were also taken at 8 h after birth from healthy and unthrifty piglets (n = 4/group). The raphe nucleus was dissected out and analyzed for 5-HT and dopamine concentrations as well as their major metabolites 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA), respectively. Data were analyzed by ANOVA. Piglets that died within 48 h of birth (n = 14) had significantly lower umbilical blood 5-HT concentrations at the time of their birth compared to their healthy counterparts (n = 46, P = 0.003). However, no difference in Trp was detected (P 0.38). Time spent under the heat lamp and sleeping were positively correlated with umbilical 5-HT levels (P = 0.004 and P = 0.02, respectively), while inactivity had a negative correlation with 5-HT levels (P = 0.04). In the raphe nucleus, the center for brain 5-HT biosynthesis, unthrifty piglets had a greater concentration of 5-HIAA (P = 0.02) and a trend for higher concentrations of 5-HT (P = 0.07) compared with healthy piglets. Dopamine levels did not differ between thrifty and unthrifty piglets (P = 0.45); however, its metabolite HVA tended to be greater in unthrifty piglets (P = 0.05). Our results show evidence of serotonergic dysfunction, at both the central and peripheral levels, accompanying early piglet mortalities. These data suggest a possible route for intervention, via the 5-HT system, to improve piglet survivability. However, further research is required to validate this hypothesis.

Free-access stalls allow sows to choose the protection of a stall or use of a shared group space. This study investigated the effect of group space width, 0.91 (SS), 2.13 (IS), and 3.05 (LS) m, on the health, production, behavior, and welfare of gestating sows. Nine replications of 21 (N = 189) gestating sows were used. At gestational d 35.4 ± 2.3, the pregnant sows were distributed into 3 pens of 7 sows, where they remained until 104.6 ± 3.5 d. Each treatment pen had 7 free-access stalls and a group space that together provided 1.93 (SS), 2.68 (IS), or 3.24 (LS) m(2)/sow. Baseline measurements were obtained before mixing. Back fat depth, BW, BCS, and lameness were measured monthly, and skin lesions were scored weekly. Blood was collected monthly for hematological, immunological, and cortisol analyses. Sow behavior was video recorded continuously during the initial 4 d of treatment and 24 h every other week thereafter. Behavior was analyzed for location, posture, pen investigation, social contact, and aggression. Skin response to the mitogen concanavalin A (Con A) was tested at mean gestational d 106. Litter characteristics including size and weight were collected at birth and weaning. The data were analyzed using a mixed model. Multiple comparisons were adjusted with the Tukey-Kramer and Bejamini-Hochberg methods. Group space allowance had no effect on any measure of sow health, physiology, or production (P ≥ 0.10). Sows in the SS, IS, and LS pens spent 77.88% ± 3.88%, 66.02% ± 3.87%, and 63.64% ± 3.91%, respectively, of their time in the free-access stalls (P = 0.12). However, SS sows used the group space less than IS and LS sows (P = 0.01). Overall, pen investigatory behavior was not affected by group space allowance (P = 0.91). Sows in the LS pens spent more time in a social group than SS sows (P = 0.02), whereas sows in IS pens were intermediate to, but not different from, the other treatments (P ≥ 0.10). The size of the social groups was also affected by the group space allowance (P = 0.03), with SS sows forming smaller groups than LS sows; again, IS sows were intermediate to, but not different from, the other treatments. Although the group space allowance had no measurable impact on the health, physiology, or productivity of the sows, the lower group space use and social contact of the SS sows reduced the behavioral diversity benefits of group housing and may indicate an avoidance of social stressors or a lack of physical comfort in the smallest pens.