Journal of Animal Science

Long, C. J.;Stein, H. H.;Felix, T. L.

doi: 10.2527/asasmw.2017.111pmid: N/A

Abstract Objectives were to determine the interactions of phytase inclusion and dietary phosphorus concentration on metabolism of beef cattle fed a starch-based diet. Six ruminally fistulated steers (initial BW = 750 ± 61 kg) were allotted to a 6 × 6 Latin square design with a 3 × 2 factorial arrangement of treatments. Factors included phytase inclusion, at 0, 500, or 2000 phytase units (FTU)/kg of diet DM, and dietary P concentration, at 0.10% and 0.30% of total diet DM. Data were analyzed using the MIXED procedure of SAS with animal as the experimental unit. The CORR procedure was used to compare P concentrations between samples. There were no treatment interactions (P ≥ 0.30) for any parameter measured. There were no main effects (P ≥ 0.45) of phytase on DMI, total fecal output, apparent DM digestibility, water intake, or urinary output. Steers fed 0.10% P had decreased (P < 0.01) DMI and total fecal output but increased (P < 0.01) apparent DM digestibility compared with steers fed 0.30% P. Although N intake and retention were not affected by treatment, steers fed the 0.10% P diet tended (P = 0.10) to absorb more N and excrete more N in the urine (P = 0.02) and less N in the feces (P < 0.01) compared with steers fed 0.30% P. Steers fed 0.10% P also consumed 70.1% less (P < 0.01) total P each day and excreted 51.9% less P in the feces (P < 0.01) and 94.6% less P in the urine (P < 0.01) compared with steers fed 0.30% P. Water-soluble P in the feces was greater (P < 0.01) on a g/d basis in steers fed 0.30% P when compared with steers fed 0.10% P. However, the proportion of total fecal P excreted as water-soluble P increased by 23.0% in cattle fed 0.10% P compared with steers fed 0.30% P, regardless of phytase inclusion level. There was no effect of dietary phytase concentration on blood or urinary (P ≥ 0.27) P concentrations. Blood P concentration was positively correlated (r = 0.60; P < 0.01) with urinary P concentration when steers were fed 0.10% P; however, when steers were fed 0.30% P, there was no correlation (r = 0.36; P = 0.16). Regardless of dietary P concentration, phytase supplementation did not increase P absorption or retention. American Society of Animal Science

Shriver, A.

doi: 10.2527/asasmw.2017.001pmid: N/A

Abstract Most people agree that unnecessarily causing severe pain in livestock can be morally problematic. But how much moral weight should we put on different intensity levels of pain? And how do we decide which pains are truly unnecessary? In this presentation, I describe how philosophers approach the problem of assessing the moral significance of pain in livestock. I will consider different views on how to weigh the moral significance of pain and how these views lead to different policy recommendations. I will examine the concept of “necessary” used in arguments suggesting that causing unnecessary pain is morally problematic, including a discussion of how pain has been evolutionarily adaptive and how it can be behaviorally beneficial. Finally, I will discuss the ethical dimensions of various proposals for how pain in livestock can be minimized. American Society of Animal Science

Coetzee, H.

doi: 10.2527/asasmw.2017.002pmid: N/A

Abstract Societal concern about the moral and ethical treatment of animals is increasing. In particular, the negative public perception of pain associated with routine animal management practices such as dehorning and castration is mounting, with increasing call for the development of practices to relieve pain and suffering in livestock. Preemptive analgesia can be applied in advance of the painful stimulus, thereby reducing sensitization of the nervous system to subsequent stimuli that could amplify pain. Agents that could be used to provide preemptive analgesia include local anesthetics, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, α2-agonists, and N-methyl D-aspartate receptor antagonists. However, less than 20% of U.S. veterinarians currently report using analgesia routinely at the time of dehorning and castration. There are several challenges associated with providing effective analgesia in food animals in the United States. Most notably, that there are currently no analgesic drugs specifically approved by the Food and Drug Administration (FDA) for the alleviation of pain in livestock. Therefore, use of any drug for pain relief constitutes extra-label drug use (ELDU) and is regulated by the Animal Medicinal Drug Use Clarification Act of 1994 (AMDUCA, 1994). A list of compounds available for potential ELDU for pain relief in cattle in the United States can be found in Table 002. The capacity to experience pain is considered to have a protective role by eliciting behavioral responses aimed at reducing further tissue damage and enhance wound healing. However, persistent pain syndromes offer no biological advantage and are associated with suffering and distress. Pathological pain states in cattle occur as a result of tissue damage, nerve damage, and inflammation and are frequently associated with pain hypersensitivity. Pain hypersensitivity manifests as hyperalgesia (exaggerated responses to painful stimuli) and allodynia (pain resulting from normally innocuous stimuli). Hyperalgesia has been reported to persist in dairy cattle and lame sheep for at least 28 d after the causal lesion has resolved. Consequently, chronic pain associated with lameness is considered one of the most significant welfare concerns in dairy cows. Inflammatory pain associated with lameness responds modestly to treatment with non-steroidal anti-inflammatory drugs (NSAIDs) but neuropathic pain (due to nerve damage or neuronal dysfunction) is considered refractory to the effects of NSAIDs and many opioid analgesics. Therefore, there is an urgent need to identify novel drugs and drug targets for alleviating chronic pain of neuropathic origin in animals. A multimodal approach using both local anesthesia and an anti-inflammatory drug optimizes pain relief in livestock procedures known to cause distress and pain. The use of meloxicam, ketoprofen, and flunixin in the development of analgesic protocols is supported by randomized controlled trials. Table 002. Drug  Approved species  Indications  Dose (cattle)  T ½ in cattle  Withhold period  Flunixin meglumine (Merck®)  Cattle, horses, and pigs  Antipyretic, anti-inflammatory.BRD and mastitis  2.2 mg/kg IV ONLY! Oral F = 60%  3–8 h  Meat: 4 days Milk: 36 h  Phenylbutazone  Horses and dogs  Anti-inflammatory  4 mg/kg IV ONLY!  40–55 h  Not approved in cattle in the USA  Ketoprofen (Merial®)  Horses and dogs  Anti-inflammatory  1.5 mg/kg IV, IM  0.42 h  Not approved in cattle in the USA  Aspirin  No FDA approval Horses and Cattle  Reduction of fever Relief of minor muscle aches and joint pain  50–100 mg/kg PO Oral F < 20%  0.5 h (IV salicylate)  No formal FDA approval. Not for use in lactating cattle  Carprofen (Zoeitis®)  EU approval in cattle Dogs  Adjunctive therapy of acute restiratory disease and mastitis  1.4 mg/kg bodyweight IV or SC Oral tablets  Age dependent <10 weeks: 49.7 h  Not approved in cattle in the USA EU: 21 days (meat), 0 days (milk)  Meloxicam (Boehringer Ingelheim®)  EU and Canadian approval in cattle Dogs and cats  Adjunctive of BRD; diarrhea and acute mastitis (EU). Analgesia after disbudding (Can)  0.5 IV, SC 0.5–1 mg/kg PO Oral F = 100%  27 h (Range: 19.97–43.29 h)  Not approved in cattle in the USA. 15 days EU and 20 days Canada. FARAD 21 days (meat)  Firocoxib (Merial®)  Dogs and horses  Anti-inflammatory  0.5 mg/kg (PO) Oral F = 98.4%  18.8 h (Range: 14.2–25.5 h)  Not approved in cattle in the USA or EU.  Drug  Approved species  Indications  Dose (cattle)  T ½ in cattle  Withhold period  Flunixin meglumine (Merck®)  Cattle, horses, and pigs  Antipyretic, anti-inflammatory.BRD and mastitis  2.2 mg/kg IV ONLY! Oral F = 60%  3–8 h  Meat: 4 days Milk: 36 h  Phenylbutazone  Horses and dogs  Anti-inflammatory  4 mg/kg IV ONLY!  40–55 h  Not approved in cattle in the USA  Ketoprofen (Merial®)  Horses and dogs  Anti-inflammatory  1.5 mg/kg IV, IM  0.42 h  Not approved in cattle in the USA  Aspirin  No FDA approval Horses and Cattle  Reduction of fever Relief of minor muscle aches and joint pain  50–100 mg/kg PO Oral F < 20%  0.5 h (IV salicylate)  No formal FDA approval. Not for use in lactating cattle  Carprofen (Zoeitis®)  EU approval in cattle Dogs  Adjunctive therapy of acute restiratory disease and mastitis  1.4 mg/kg bodyweight IV or SC Oral tablets  Age dependent <10 weeks: 49.7 h  Not approved in cattle in the USA EU: 21 days (meat), 0 days (milk)  Meloxicam (Boehringer Ingelheim®)  EU and Canadian approval in cattle Dogs and cats  Adjunctive of BRD; diarrhea and acute mastitis (EU). Analgesia after disbudding (Can)  0.5 IV, SC 0.5–1 mg/kg PO Oral F = 100%  27 h (Range: 19.97–43.29 h)  Not approved in cattle in the USA. 15 days EU and 20 days Canada. FARAD 21 days (meat)  Firocoxib (Merial®)  Dogs and horses  Anti-inflammatory  0.5 mg/kg (PO) Oral F = 98.4%  18.8 h (Range: 14.2–25.5 h)  Not approved in cattle in the USA or EU.  Table 002. Drug  Approved species  Indications  Dose (cattle)  T ½ in cattle  Withhold period  Flunixin meglumine (Merck®)  Cattle, horses, and pigs  Antipyretic, anti-inflammatory.BRD and mastitis  2.2 mg/kg IV ONLY! Oral F = 60%  3–8 h  Meat: 4 days Milk: 36 h  Phenylbutazone  Horses and dogs  Anti-inflammatory  4 mg/kg IV ONLY!  40–55 h  Not approved in cattle in the USA  Ketoprofen (Merial®)  Horses and dogs  Anti-inflammatory  1.5 mg/kg IV, IM  0.42 h  Not approved in cattle in the USA  Aspirin  No FDA approval Horses and Cattle  Reduction of fever Relief of minor muscle aches and joint pain  50–100 mg/kg PO Oral F < 20%  0.5 h (IV salicylate)  No formal FDA approval. Not for use in lactating cattle  Carprofen (Zoeitis®)  EU approval in cattle Dogs  Adjunctive therapy of acute restiratory disease and mastitis  1.4 mg/kg bodyweight IV or SC Oral tablets  Age dependent <10 weeks: 49.7 h  Not approved in cattle in the USA EU: 21 days (meat), 0 days (milk)  Meloxicam (Boehringer Ingelheim®)  EU and Canadian approval in cattle Dogs and cats  Adjunctive of BRD; diarrhea and acute mastitis (EU). Analgesia after disbudding (Can)  0.5 IV, SC 0.5–1 mg/kg PO Oral F = 100%  27 h (Range: 19.97–43.29 h)  Not approved in cattle in the USA. 15 days EU and 20 days Canada. FARAD 21 days (meat)  Firocoxib (Merial®)  Dogs and horses  Anti-inflammatory  0.5 mg/kg (PO) Oral F = 98.4%  18.8 h (Range: 14.2–25.5 h)  Not approved in cattle in the USA or EU.  Drug  Approved species  Indications  Dose (cattle)  T ½ in cattle  Withhold period  Flunixin meglumine (Merck®)  Cattle, horses, and pigs  Antipyretic, anti-inflammatory.BRD and mastitis  2.2 mg/kg IV ONLY! Oral F = 60%  3–8 h  Meat: 4 days Milk: 36 h  Phenylbutazone  Horses and dogs  Anti-inflammatory  4 mg/kg IV ONLY!  40–55 h  Not approved in cattle in the USA  Ketoprofen (Merial®)  Horses and dogs  Anti-inflammatory  1.5 mg/kg IV, IM  0.42 h  Not approved in cattle in the USA  Aspirin  No FDA approval Horses and Cattle  Reduction of fever Relief of minor muscle aches and joint pain  50–100 mg/kg PO Oral F < 20%  0.5 h (IV salicylate)  No formal FDA approval. Not for use in lactating cattle  Carprofen (Zoeitis®)  EU approval in cattle Dogs  Adjunctive therapy of acute restiratory disease and mastitis  1.4 mg/kg bodyweight IV or SC Oral tablets  Age dependent <10 weeks: 49.7 h  Not approved in cattle in the USA EU: 21 days (meat), 0 days (milk)  Meloxicam (Boehringer Ingelheim®)  EU and Canadian approval in cattle Dogs and cats  Adjunctive of BRD; diarrhea and acute mastitis (EU). Analgesia after disbudding (Can)  0.5 IV, SC 0.5–1 mg/kg PO Oral F = 100%  27 h (Range: 19.97–43.29 h)  Not approved in cattle in the USA. 15 days EU and 20 days Canada. FARAD 21 days (meat)  Firocoxib (Merial®)  Dogs and horses  Anti-inflammatory  0.5 mg/kg (PO) Oral F = 98.4%  18.8 h (Range: 14.2–25.5 h)  Not approved in cattle in the USA or EU.  American Society of Animal Science

Duffield, T. F.

doi: 10.2527/asasmw.2017.004pmid: N/A

Abstract One area of increasing focus of health management research has been pain management in food animals. My position at the Ontario Veterinary College allows me to teach undergraduate DVM students in all years of the program, interact with producers on farm, and conduct research both at our dairy research facility and on commercial dairy farms. Through these interactions and research experiences, I have learned many lessons over the twelve years that I have been involved in this area of research. These lessons are: 1. I teach students but students teach me. 2. Producers care about their animals and will do the right thing. 3. Not all treatments are good. 4. Dystocia hurts both the calf and the cow. 5. Sickness behavior is a key concept—particularly for producers and veterinarians. 6. Change is difficult. Through the work that our research group has conducted in pain management of disbudding, mastitis, diarrhea, calving, and surgery and surveys of changes in Ontario of both producer and veterinary approaches to disbudding in the past 10 yr, these lessons will be illustrated and explored. American Society of Animal Science

doi: 10.2527/asasmw.2017.005pmid: N/A

This content is only available as a PDF. American Society of Animal Science

Herskin, M. S.;Di Giminiani, P.

doi: 10.2527/asasmw.2017.003pmid: N/A

Abstract Despite a long history of debate about negative affective states in animals, it was only in the last decades of the 20th century that the state of pain was mentioned in definitions of animal welfare, included in veterinary education, and became a target of scientific interest. Pain is a perceptional phenomenon built from information gathered by specialized sensory receptors for tissue damage and integrated into a discrete experience with a negative emotional valence in the brain. Based on knowledge about porcine neuroanatomy, physiology, and studies focusing on pig behavior and pathology, we review evidence for causes of pain in pigs, underlying biological mechanisms, as well as the possibility to quantify different types of indicators of pain states relevant to the welfare of the animals under production conditions. The presentation will primarily focus on pigs because of the dual purpose of this species as a meat producing as well as research animal species (the latter driven by the anatomical and physiological homologies with humans), making pigs unique among livestock. We will present methodologies and results from current research projects across Europe and North America targeting typical industry-related injuries (e.g., tail docking, lameness, and shoulder lesions) and aiming to understand the welfare consequences for the pigs. Throughout the talk, the emphasis will be put on future opportunities to link research outcomes with industry initiatives toward the improvement of animal welfare and production. In addition, possible future research efforts to help face current methodological limitations and favor a more comprehensive evaluation of animal pain as an overall experience will be discussed. This seeks to facilitate common future targeted research and enable us to overcome the paradoxical low level of knowledge about porcine pain and its alleviation under production conditions. American Society of Animal Science

Mumm, J. M.;Stock, J. D.;Azarpajouh, S.;Stalder, K. J.;Johnson, A. K.;Diaz, J. A. Calderon

doi: 10.2527/asasmw.2017.006pmid: N/A

Abstract The objectives of this study were to characterize the different postures and movements for the lying down sequence in multiparous sows and to identify differences between lame and sound sows. Eighty-five multiparous sows (parity range 1 to 4) were used for this study. Sows were moved from their gestation stall to a stall in an empty area of the barn. A digital video camera was positioned on the adjacent stall so the sows' profiles were visible. Sows were video recorded for one lying down event on Days 30, 60, and 90 of gestation. Observations ceased when the sow successfully lay down or if 2.5 h elapsed since recording began. Prior to recording, sows were scored for lameness on a 3-point scale, (1 = normal to 3 = severely lame). From the video, postures and movements that occurred during the lying sequence were identified. Time from kneeling to shoulder rotation (KSR; seconds), time from shoulder rotation to lying (SRHQ; seconds), total time to lie down (TLIE; seconds), latency to lie down (LATENCY; minutes), and number of attempts (ATTEMPTS) to successfully lie down were recorded. Sows were re-classified as sound or lame. Parities were reclassified as 1, 2, and ≥ 3 due to small numbers of older sows. Time variables were analyzed using mixed-model methods. ATTEMPTS were classified as 1, 2, and ≥ 3 and analyzed using multinomial logistic regression. Models included gestation day, lameness status, and parity. On average, sows took 13.9 s for KSR, 7.7 s for SRHQ, 20.5 s for TLIE, and 66.1 min for LATENCY. Lameness was not a significant source of variation for any trait evaluated. However, lame sows tended to take longer during KSR (15.5 vs. 11.9 ± 1.59 s for lame and sound sows, respectively; P = 0.08) and to spend less time standing (54.1 vs. 69.8 ± 6.20 min for lame and sound sows, respectively; P = 0.06) compared with sound sows. Gestation day and parity were not associated with the time taken for the different movements in the lying down sequence (P > 0.05). Additionally, there were no significant associations between gestation day, lameness status, or parity and ATTEMPTS. Results suggest that lameness scores do not greatly affect the lying down sequence. However, this could be due to the fact that lameness recorded in this study was not severe enough to affect the lying down sequence. American Society of Animal Science

Mumm, J. M.;Azarpajouh, S.;Stock, J. D.;Stalder, K. J.;Johnson, A. K.;Diaz, J. A. Calderon

doi: 10.2527/asasmw.2017.007pmid: N/A

Abstract Lameness is a prominent disease in swine production, and it might affect the way sows interact with their environment. The objectives of this study were to determine the time required and the behavioral sequence to move from lying to standing for lame and non-lame sows. Eighty-five multiparous sows (parity range 1 to 4) were enrolled. Prior to recording, sows were scored for lameness while walking on a 3-point scale (1 = normal to 3 = severely lame). Sows were moved into a gestation stall where they were digitally video recorded continuously (30 frames/s) for one standing up event on Days 30, 60, and 90 of gestation. Time (sec) to stand up was defined as the first leg fold to sit (TLS), time from sit to rise (TSR), and total time to rise (TRISE). The frequency of TLS, TSR, and TRISE were also collected. Sows were re-classified as sound or lame, and parities were re-classified as 1, 2, and ≥ 3 for statistical analysis. The likelihood of performing the different movements for the standing sequence was analyzed using logistic regression. Time variables were analyzed using mixed model equation methods. Models included gestation day, lameness status, and parity. There were no significant associations between gestation day, parity, lameness, and the likelihood of performing different movements during the standing up behavioral sequence. However, lame sows tended to be more likely to sit while transitioning from lying to standing compared with sound sows (P = 0.07). On average, sows took 8.0 sec for TLS, 6.9 sec for TSR, and 9.8 sec for TRISE. Lameness did not affect the time taken for TLS, TSR, and TRISE (P > 0.05). Parity 2 sows had greater TLS compared with parity 1 sows (20.9 vs. 4.7 ± 3.01 sec; P < 0.05) and parity ≥ 3 (20.9 vs. 5.5 ± 3.62 sec; P < 0.05). Additionally, parity 2 sows tended (P = 0.09) to take 8.1 and 6.7 sec more for TRISE when compared to parity 1 and ≥ 3 sows; respectively (16.0 vs. 7.9 ± 1.9 and 9.3 ± 3.3 sec; P < 0.10). Under the conditions of this study, lameness did not influence the timings or order of the standing up sequence. However, lameness recorded was mild, and thus, it might not have been severe enough to affect the sequence. Other factors such as parity seem to be related with timing of the standing sequence. American Society of Animal Science

Tinkle, A.;Wilson, M. E.;Parsley, M. A.;Azain, M. J.;Dove, C. R.

doi: 10.2527/asasmw.2017.008pmid: N/A

Abstract The object of this study was to ascertain if blunt verses functional claw trimming provided similar benefits. Twenty-one PIC (Cambrough 29) sows were used with an average claw length of 6.5 cm and dewclaw length of 6.2 cm pre trimming. Sows were trained for 3 d before recording. Sows were individually walked through a dog bone track (7.5 m long) and recorded on a pressure mat (Gaitrite) for five useable repetitions on d 0, d 4, d 8, and d 12 of the study. After d 0, sow locomotion was recorded, dewclaws were trimmed even with coronary band. Sows were recorded on d 4, and then claws were straight cut across the toe using a lopper (Blunt cut). Sows were recorded on d 8 and then were functionally trimmed. The final recording was on d 12. Recordings were analyzed using Gaitfour (Gaitrite) software to assess swing, stance, stride length, gait cycle, percent stance of gait cycle, and overall velocity. Data were analyzed using the PROC MIXED procedure of SAS as a repeated measures design with each sow serving as her own control. There was an increase from d 0 to d 12 for velocity (P < 0.003; d 0 94.8, d 8 97.62) and d 8 to d 12 (P < 0.009; d 0 94.8, d 12 105.5 cm/s), stride length (front d 0 to d 12, P < 0.003; d 8 to d 12, P < 0.035; 97.80, 99.74, 101.77 cm; rear 98.09, 99.04, 101.67 cm on d 0, d 8, and d 12, respectively) and percent stance of gait cycle (front d 0 to d 12, P < 0.0001; d 8 to d 12, P < 0.001; 69.06, 69.95, 65.68%; rear d 0 to d 12, P < 0.001; d 8 to d 12, P < 0.002; 67.49, 66.04, 64.12% on d 0, d 8, and d 12, respectively). There was a decrease from d 0 to d 12 and d 8 to d 12 for stance (front d 0 to d 12, P < 0.0001; d 8 to d 12, P < 0.0041; 0.75, 0.7, 0.66 s; rear d 0 to d 12, P < 0.0001; d 8 to d 12, P < 0.005; 0.75, 0.71, 0.6 s on d 0, d 8, and d 12 respectively) and gait cycle (front d 0 to d 12, P < 0.003; d 8 to d 12, P < 0.03; 1.08, 1.04, 0.99 s; rear d 0 to d 12, P < 0.0012; d 8 to d 12, P < 0.02; 1.11, 99.04, 1.01 s on d 0, d 8, and d 12, respectively). This illustrates that blunt cut trimming the claw is not enough to improve gait quality in the sows and functional trimming will provide better results in sow locomotion. American Society of Animal Science

Rauw, W. M.;Mayorga, E. J.;Lei, S.;Dekkers, J. C. M.;Patience, J. F.;Gabler, N. K.;Lonergan, S. M.;Baumgard, L. H.

doi: 10.2527/asasmw.2017.009pmid: N/A

Abstract Heat stress (HS) accounts for over $900 million loss in the US swine industry annually. In addition, HS negatively impacts animal welfare. Evidence suggests that efficient, fast-growing pigs may be more susceptible to HS. Study objectives were to investigate the effects of genetics on respiration rate (RR) and skin (ST) and rectal temperatures (RT) in response to repeated exposure to HS. A total of 97 animals from a commercial line and a divergent line selected for high and low residual feed intake (RFI) were subjected three times to a 4-d HS load that was preceded by a 9-d thermal neutral (TN) adaptation period and alternated by 7-d TN conditions: 1-TN adaptation, 2-HS, 3-TN, 4-HS, 5-TN, 6-HS, and 7-TN. RR, ST, and RT were measured daily in each period. Mixed models with a repeated statement were fitted to describe the individual data. RR, ST, and RT were higher during HS compared with TN conditions (P < 0.0001; Table 009). RR was positively correlated with ST during TN (r = 0.27; P < 0.0001) but not during HS (r = 0.03). Commercial pigs had higher RR than low and high RFI pigs during TN (P < 0.05); high RFI pigs had higher RR than commercial and low RFI pigs during HS (P < 0.05). During TN, ST and RT were higher in commercial pigs than in low and high RFI pigs and higher in high RFI than in low RFI pigs (P < 0.001). During HS, ST and RT were higher in commercial pigs than in low and high RFI pigs (P < 0.01). Results indicate that fast growing commercial pigs had higher body temperatures that reached fever temperatures during HS. This suggests that fast growing animals may be more affected by HS, which may negatively impact their welfare. Selection for increased feed efficiency may eventually result in pigs that are less affected by heat stress. Table 009. Least square means ± s.e. for RR, ST, and RT for pigs from a commercial, low RFI and high RFI line during HS and TN conditions.   RR (bpm)  ST (°C)  RT ST (°C)    TN  HS  TN  HS  TN  HS  Commercial  42 ± 1  93 ± 2  33.8 ± 0.1  37.8 ± 0.1  39.4 ± 0.02  40.0 ± 0.03  Low RFI  34 ± 1  92 ± 1  32.2 ± 0.1  37.3 ± 0.1  39.1 ± 0.02  39.4 ± 0.03  High RFI  39 ± 1  100 ± 2  32.5 ± 0.1  37.4 ± 0.1  39.2 ± 0.02  39.5 ± 0.03    RR (bpm)  ST (°C)  RT ST (°C)    TN  HS  TN  HS  TN  HS  Commercial  42 ± 1  93 ± 2  33.8 ± 0.1  37.8 ± 0.1  39.4 ± 0.02  40.0 ± 0.03  Low RFI  34 ± 1  92 ± 1  32.2 ± 0.1  37.3 ± 0.1  39.1 ± 0.02  39.4 ± 0.03  High RFI  39 ± 1  100 ± 2  32.5 ± 0.1  37.4 ± 0.1  39.2 ± 0.02  39.5 ± 0.03  Table 009. Least square means ± s.e. for RR, ST, and RT for pigs from a commercial, low RFI and high RFI line during HS and TN conditions.   RR (bpm)  ST (°C)  RT ST (°C)    TN  HS  TN  HS  TN  HS  Commercial  42 ± 1  93 ± 2  33.8 ± 0.1  37.8 ± 0.1  39.4 ± 0.02  40.0 ± 0.03  Low RFI  34 ± 1  92 ± 1  32.2 ± 0.1  37.3 ± 0.1  39.1 ± 0.02  39.4 ± 0.03  High RFI  39 ± 1  100 ± 2  32.5 ± 0.1  37.4 ± 0.1  39.2 ± 0.02  39.5 ± 0.03    RR (bpm)  ST (°C)  RT ST (°C)    TN  HS  TN  HS  TN  HS  Commercial  42 ± 1  93 ± 2  33.8 ± 0.1  37.8 ± 0.1  39.4 ± 0.02  40.0 ± 0.03  Low RFI  34 ± 1  92 ± 1  32.2 ± 0.1  37.3 ± 0.1  39.1 ± 0.02  39.4 ± 0.03  High RFI  39 ± 1  100 ± 2  32.5 ± 0.1  37.4 ± 0.1  39.2 ± 0.02  39.5 ± 0.03  American Society of Animal Science