Suitability of four injectable anesthetic protocols for percutaneous synovial fluid aspiration in healthy swine under field conditions and assessment of lameness seven days post procedure

Objective: To compare the suitability of four anesthetic protocols for ante-mortem percutaneous synovial fluid aspiration from healthy swine in field conditions. A supplemental objective was to assess the iatrogenic impact of ante-mortem joint sampling by monitoring lameness and joint swelling after the procedure and assessing synovium histology at day seven post treatment. Materials and methods: Twenty-four finisher pigs (mean weight 86.1 kg ± 10.6) were each randomly allocated to receive one of four intramuscularly administered anesthetic protocols: telazol-ketamine-xylazine (TKX); telazol-ketamine-acepromazine (TKA); ketamine-acepromazine with lidocaine epidural (KAL); or telazol-acepromazine with lidocaine epidural (TAL). Synovial fluid was collected aseptically from one carpus and tarsus joint per anesthetized pig. The anesthetic protocols were evaluated in terms of successful general anesthesia, time to sternal recumbency and time to standing recovery, and protocol cost. Joint swelling and lameness assessments were completed on days two, four, and seven post sampling. On day seven, pigs were euthanized and synovium was collected from each sampled joint for histologic evaluation. Results: The TKX and TAL treatments were the only anesthetic combinations that provided an adequate anesthesia depth for fluid collection to occur. Mean (SD) time to sternal recumbency for TKX was 125 (26) minutes and for TAL was 198 (28) minutes. There was no evidence of post-aspiration infection in any sampled joints. Implications: The TKX treatment was the most effective anesthetic protocol for ante-mortem joint fluid collection. Ante-mortem joint fluid collection was not associated with significant joint tissue damage and can be a useful diagnostic tool for infectious arthritis

Determination of reference intervals for fluid analysis and cytologic evaluation variables in synovial fluid samples obtained from carpal and tarsal joints in commercial nonlame growing swine

OBJECTIVE To determine reference intervals for total nucleated cell count, total protein concentration, pH, RBC count, and percentages of neutrophils, lymphocytes, and large mononuclear cells in synovial fluid samples (SFSs) obtained from the carpal and tarsal joints of healthy swine. ANIMALS 54 healthy commercial finisher pigs that had no evidence of lameness or gross joint swelling. PROCEDURES Each pig was anesthetized, and SFSs were collected from 1 carpal and 1 tarsal joint for fluid analysis, cytologic evaluation, bacterial culture, and PCR analyses for common swine joint pathogens. Each pig was euthanized after SFS collection, and synovial tissue samples were collected for histologic assessment. If necessary, postmortem SFSs were collected. RESULTS Overall, 37 of 50 tarsal and 46 of 53 carpal SFSs met inclusion criteria of sufficient volume, no gross blood contamination, and negative results of bacterial culture and PCR analyses, and were from joints with histologically normal synovial tissues. For the carpal and tarsal joints, upper reference limits were as follows: total nucleated cell count, 3,281 cells/μL and 2,368 cells/μL, respectively; total protein concentration, 3.6 g/dL and 3.6 g/dL, respectively; pH, 7.2 and 7.0, respectively; RBC count, 0.8 X 106 cells/μL and 0.1 X 106 cells/μL, respectively; and percentage of neutrophils, 46.5% and 33.7%, respectively; percentage of lymphocytes, 40.6% and 56.3%, respectively; and percentage of large mononuclear cells, 92.0% and 95.3%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results have provided reference intervals for selected variables in SFSs obtained from the carpal and the tarsal joints of healthy swine, which should be useful in diagnostic investigations of swine lameness and arthritis

Longitudinal and Cross-Sectional Evaluation of Two Commercial Swine Breeding Herds to Characterize Neutralizing Antibody Levels following Porcine Epidemic Diarrhea Virus Outbreaks

Neutralizing antibodies to Porcine Epidemic Diarrhea Virus (PEDV) can be detected by 3 weeks post-infection and remain detectable through at least 24 weeks post-infection. The objective of this study was to evaluate the levels of neutralizing antibodies in sow and piglet serum and sow milk to determine the duration of neutralizing antibodies following PEDV outbreaks. Two farms were selected for the study following outbreaks of PEDV. Monthly, cohorts of sows were sampled and followed through two farrowings. Following each farrowing, samples from piglets and milk were collected. Samples were evaluated for PEDV-neutralizing antibodies by a high-throughput fluorescent neutralization assay. Although neutralizing antibodies to PEDV can be detected throughout 15 months post-outbreak, a decrease in circulating neutralizing antibody levels is noted in farms beginning at six months post-outbreak. With decreasing levels, farms may become more vulnerable to PEDV outbreaks, and practitioners can focus on this time window to implement intervention strategies

The effects of dietary essential fatty acid ratios and linoleic acid level in grow–finish pigs

The objective of this study was to investigate the effects of dietary linoleic acid level and the ratio of linoleic acid:linolenic acid (LA:ALA) on the growth performance, expression of genes associated with lipid metabolism and inflammatory status of grow-finish pigs. A total of 300 growing pigs (BW = 41.1 ± 6.3 kg) were randomly assigned to either a high (30 g/kg; HLA) or low (15 g/kg; LLA) dietary linoleic acid level with a high (23:1; HR), moderate (13:1; MR) or low (4:1; LR) dietary LA:ALA in a 2 3 factorial design. Diets were fed across three 28-day phases and were balanced for dietary metabolizable energy. Pigs were housed 5 pigs per pen in single-sex pens. Blood samples were collected on d 0, 21, 42, and 84, and synovial fluid was collected from the hock joint on d 0 and 84 for inflammatory marker analysis. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4) with initial body weight as a covariate, pen as the experimental unit, and LA level, LA:ALA, sex, phases, and their interactions as fixed effects. Compared to HLA, LLA pigs tended to have increased BW at d 56 and d 84 (P = 0.088). There was no effect of LA LA:ALA for growth performance. For the overall d 0 – 84 growth period, pigs fed HR had increased ADG compared to MR, with pigs receiving LR performing intermediate of MR and HR. Gilts receiving HR diets had increased d 84 BW compared to gilts receiving the low and moderate LA:ALA (P = 0.006), which was a result of improved overall d 0 – 84 ADG compared to gilts receiving the MR diets (P = 0.023). Barrows fed LR had improved BW on d 56 compared to MR and HR and higher final BW compared to HR, with MR performing intermediately (P = 0.006). This was a result of greater d 0 – 84 ADG (P = 0.023). Overall, C-reactive protein (CRP), tumor necrosis factor-α (TNFα), and interleukin-6 (IL-6) were reduced in the plasma of pigs over time (P ≤ 0.037). Across all treatments, CRP and TNFα were reduced in the hock and carpus synovial fluid on d 84 vs. d 0 (P ≤ 0.049). In conclusion, LA:ALA ratios utilized in this study can be fed at varying linoleic acid levels without impacting growth or inflammation. Additionally, LA:ALA ratios can differentially impact the growth of gilts and barrows.This is a manuscript of an article published as Spenser L Becker, Dalton C Humphrey, Locke A Karriker, Justin T Brown, Kristin J Skoland, Laura L Greiner, The effects of dietary essential fatty acid ratios and linoleic acid level in grow–finish pigs, Journal of Animal Science, Volume 101, 2023, skad263, https://doi.org/10.1093/jas/skad263. © The Author(s) 2023. Posted with permission

The effects of dietary essential fatty acid ratios and energy level on growth performance, lipid metabolism, and inflammation in grow-finish pigs

The objective of this study was to investigate the effects of dietary metabolizable energy (ME) level and the ratio of linoleic acid:α-linolenic acid (LA:ALA) on the growth performance, lipid metabolism, circulatory and joint inflammatory status, and synovial fluid proteome of grow-finish pigs. A total of 224 pigs (BW = 41.5 ± 6.1 kg; PIC Genus 337 × 1050, Hendersonville, TN) were randomly assigned to either a high (3.55 Mcal/kg; HE) or low (3.29 Mcal/kg; LE) ME dietary treatment with a high (23:1) or low (12:1) LA:ALA in a 2 × 2 factorial arrangement. Diets were fed across three 28-d phases. Pigs were housed either four barrows or four gilts per pen. Blood samples were collected on days 0, 21, 42, and 84. Synovial fluid was collected from the hock and carpus joints on days 0 and 84. Liver and adipose tissue samples were collected on day 84. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4) with pen as the experimental unit and energy level, essential fatty acid ratio, sex, phase, and their interactions as fixed effects. Compared to LE, HE increased days 28, 56, and 84 body weight (BW; P = 0.005). For the overall period, HE increased average daily gain (ADG) compared to LE (P < 0.001) and improved feed efficiency (P = 0.001), while LE increased feed intake compared to HE (P < 0.001). Gilts receiving diets with low LA:ALA had similar final BW to barrows receiving a low LA:ALA at days 28, 56, and 84 (P = 0.024), resulting from improved overall days 0–84 ADG compared to gilts receiving the high LA:ALA (P = 0.031). In the liver, HE decreased the mRNA abundance of acetyl CoA carboxylase (ACACA; P = 0.004), cluster of differentiation 36 (P = 0.034), and tended to decrease fatty acid synthase (FASN; P = 0.056). In adipose tissue, HE decreased ACACA (P = 0.001) and FASN (P = 0.017). Plasma inflammatory markers C-reactive protein (CRP) and tumor necrosis factor-α (TNFα) were reduced on day 84 compared to day 0 (P ≤ 0.014). In the hock and carpus synovial fluid, LE tended to reduce CRP and TNFα (P ≤ 0.096). Hock and carpus synovial fluid CRP were also reduced on day 84 compared to day 0 (P = 0.001). Age of the pig impacted serum and hock synovial fluid protein abundance, but not energy level, LA:ALA, or their interactions (P < 0.05). To conclude, the high and low LA:ALA ratios utilized in this study can be fed at varying energy levels without impacting growth. Additionally, LA:ALA ratios can differentially impact the growth of barrows and gilts.This article is published as Becker, Spenser L., Dalton C. Humphrey, Locke A. Karriker, Justin T. Brown, Kristin J. Skoland, and Laura L. Greiner. "The effects of dietary essential fatty acid ratios and energy level on growth performance, lipid metabolism, and inflammation in grow-finish pigs." Journal of Animal Science 101 (2023): skad151. DOI: 10.1093/jas/skad151. Copyright 2023 The Author(s). Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0). Posted with permission

Efficacy of a commercial porcine epidemic diarrhea virus vaccine at reducing duration of viral shedding in gilts

Objective: To evaluate if the use of a commercially available killed porcine epidemic diarrhea virus (PEDV) vaccine shortens the duration of PEDV shedding in replacement gilts. Materials and methods: Four treatment groups composed of 20 females were utilized for this study. Gilts in the CONTROL group had no previous exposure to PEDV, the nonvaccinated (NV) group had been previously exposed, and the PRE and POST groups received two doses of a commercial, killed PEDV vaccine either prior to or following a challenge with PEDV, respectively. Individual fecal samples were collected weekly and tested by real-time reverse transcription-polymerase chain reaction (rRT-PCR) for virus detection. Results: Previous exposure to PEDV was found to shorten the time that virus can be detected in the feces compared to fecal samples of naïve animals (P < .001). Vaccination, either prior to or following the challenge, was not found to shorten the duration of PEDV shedding in feces. Implications: These results showed that vaccination of gilts, either prior to the challenge or afterwards, with a killed commerical PEDV vaccine did not shorten the period that virus was detectable in the feces by rRT-PCR suggesting that viral shedding in feces was not influenced by administration of a killed commercial vaccine. While previous infection with virulent PEDV did not prevent re-infection, it did have a significant effect on the amount of time virus was detected following a subsequent exposure.This article is published as Brown, Justin, Chris Rademacher, Samuel Baker, Korakrit Poonsuk, Ting-Yu Cheng, Kristin Skoland, Paisley Canning, Anna Forseth, and Locke Karriker. "Efficacy of a commercial porcine epidemic diarrhea virus vaccine at reducing duration of viral shedding in gilts." Journal of Swine Health and Production 27, no. 5 (2019): 256-264. Copyright 2019 American Association of Swine Veterinarians. Posted with permission

Suitability of four injectable anesthetic protocols for percutaneous synovial fluid aspiration in healthy swine under field conditions and assessment of lameness seven days post procedure

Objective: To compare the suitability of four anesthetic protocols for ante-mortem percutaneous synovial fluid aspiration from healthy swine in field conditions. A supplemental objective was to assess the iatrogenic impact of ante-mortem joint sampling by monitoring lameness and joint swelling after the procedure and assessing synovium histology at day seven post treatment. Materials and methods: Twenty-four finisher pigs (mean weight 86.1 kg ± 10.6) were each randomly allocated to receive one of four intramuscularly administered anesthetic protocols: telazol-ketamine-xylazine (TKX); telazol-ketamine-acepromazine (TKA); ketamine-acepromazine with lidocaine epidural (KAL); or telazol-acepromazine with lidocaine epidural (TAL). Synovial fluid was collected aseptically from one carpus and tarsus joint per anesthetized pig. The anesthetic protocols were evaluated in terms of successful general anesthesia, time to sternal recumbency and time to standing recovery, and protocol cost. Joint swelling and lameness assessments were completed on days two, four, and seven post sampling. On day seven, pigs were euthanized and synovium was collected from each sampled joint for histologic evaluation. Results: The TKX and TAL treatments were the only anesthetic combinations that provided an adequate anesthesia depth for fluid collection to occur. Mean (SD) time to sternal recumbency for TKX was 125 (26) minutes and for TAL was 198 (28) minutes. There was no evidence of post-aspiration infection in any sampled joints. Implications: The TKX treatment was the most effective anesthetic protocol for ante-mortem joint fluid collection. Ante-mortem joint fluid collection was not associated with significant joint tissue damage and can be a useful diagnostic tool for infectious arthritis.This article is published as Canning, Paisley, Katie O’Brien, Victoria Thompson, Darin Madson, Kristin Skoland, Alejandro Ramirez, Daniel Linhares, Phillip Gauger, and Locke Karriker. "Suitability of four injectable anesthetic protocols for percutaneous synovial fluid aspiration in healthy swine under field conditions and assessment of lameness seven days post procedure." Journal of Swine Health and Production 26, no. 3 (2018): 130-136. Posted with permission.</p

Determination of reference intervals for fluid analysis and cytologic evaluation variables in synovial fluid samples obtained from carpal and tarsal joints in commercial nonlame growing swine

OBJECTIVE To determine reference intervals for total nucleated cell count, total protein concentration, pH, RBC count, and percentages of neutrophils, lymphocytes, and large mononuclear cells in synovial fluid samples (SFSs) obtained from the carpal and tarsal joints of healthy swine. ANIMALS 54 healthy commercial finisher pigs that had no evidence of lameness or gross joint swelling. PROCEDURES Each pig was anesthetized, and SFSs were collected from 1 carpal and 1 tarsal joint for fluid analysis, cytologic evaluation, bacterial culture, and PCR analyses for common swine joint pathogens. Each pig was euthanized after SFS collection, and synovial tissue samples were collected for histologic assessment. If necessary, postmortem SFSs were collected. RESULTS Overall, 37 of 50 tarsal and 46 of 53 carpal SFSs met inclusion criteria of sufficient volume, no gross blood contamination, and negative results of bacterial culture and PCR analyses, and were from joints with histologically normal synovial tissues. For the carpal and tarsal joints, upper reference limits were as follows: total nucleated cell count, 3,281 cells/μL and 2,368 cells/μL, respectively; total protein concentration, 3.6 g/dL and 3.6 g/dL, respectively; pH, 7.2 and 7.0, respectively; RBC count, 0.8 X 106 cells/μL and 0.1 X 106 cells/μL, respectively; and percentage of neutrophils, 46.5% and 33.7%, respectively; percentage of lymphocytes, 40.6% and 56.3%, respectively; and percentage of large mononuclear cells, 92.0% and 95.3%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results have provided reference intervals for selected variables in SFSs obtained from the carpal and the tarsal joints of healthy swine, which should be useful in diagnostic investigations of swine lameness and arthritis.This article is published as Canning, Paisley, Austin Viall, Katie O'Brien, Darin Madson, Kristin Skoland, Adam Krull, Daniel Linhares, Phillip Gauger, Alejandro Ramirez, and Locke Karriker. "Determination of reference intervals for fluid analysis and cytologic evaluation variables in synovial fluid samples obtained from carpal and tarsal joints in commercial nonlame growing swine." American Journal of Veterinary Research 79, no. 8 (2018): 858-866. DOI: 10.2460/ajvr.79.8.858. Posted with permission.</p

Effect of direct-fed microbial Bacillus subtilis C-3102 on enteric health in nursery pigs after challenge with porcine epidemic diarrhea virus

Objective: To examine the effects of feeding Bacillus subtilis C-3102 at the target inclusion rates of 0 colony forming units (CFU) per g, 500,000 CFU per g, and 1 million CFU per g on intestinal health in weaned pigs after challenge with porcine epidemic diarrhea virus (PEDV). Materials and methods: A two-by-three factorial design was conducted, composed of three experimental diets and PEDV or sham challenge. Sixty 14-day-old pigs, negative for PEDV by quantitative real-time reverse transcription polymerase chain reaction (PCR) and negative by PCR for porcine reproductive and respiratory syndrome virus, were randomly allocated into six treatment groups with 10 pigs per group. Pigs were housed in groups of five in solid-floor pens. Treatment diets were fed for a total of 23 days, including 19 days before and 4 days after PEDV challenge or sham challenge by oral gavage. Results: Pathological changes associated with PEDV were significantly less severe in challenged treatment groups that received B subtilis C-3102 than in the group that received no B subtilis treatment. There were no significant differences in small intestinal length, ratio of small intestinal weight to body weight, colon dry matter content, average daily gain, or fecal scoring between any of the six treatment groups. Implication: Under the conditions of this study, treatment with B subtilis C-3102 in nursery pigs challenged with PEDV is associated with better enteric health than in pigs not treated with B subtilis C-3102.This article is published as Canning, P., C. Ruston, D. Madson, J. Bates, K. Skoland, J. Davenport, S. Gaul, C. Wang, Q. Chen, J. Zhang, and L. Karriker. "Effect of direct-fed microbial Bacillus subtilis C-3102 on enteric health in nursery pigs after challenge with porcine epidemic diarrhea virus." Journal of Swine Health and Production 25, no. 3 (2017): 129-137.</p

Evaluation of a staged loadout procedure for market swine to prevent transfer of pathogen contaminated particles from livestock trailers to the barn

Objective: Evaluate the effectiveness of a staged market pig loading procedure for reducing contaminant transfer from livestock trailers to the barn. Materials and methods: A conventional loading procedure was compared to a staged procedure, with 10 replicates each. In the staged procedure, one loadout crew member was stationed between two lines of separation and could not cross onto the livestock trailer or into the center alleyway of the barn. The remaining loadout crew members within the barn could not cross into the loadout alleyway or chute. In the conventional procedure, a loadout crew member moved pigs from the center alleyway, through the loadout alleyway, and up the chute, but did not cross onto the livestock trailer. Fluorescent powder was mixed with obstetrical lubricant and wood shavings and spread evenly on the livestock trailer floor, just inside the roll-up door that opens to the chute. After each loadout, fluorescent powder contamination was evaluated at 8 locations: one in the chute, two in the loadout alleyway, and five in the center alleyway of the barn. Results: Four of five center alleyway locations had significantly lower contamination (P .05). Implications: The staged loading procedure effectively reduced the transfer of fluorescent powder from the livestock trailer to the barn.This article is published as Ruston, Chelsea R., Daniel Linhares, Eli Blay, Megan Nickel, Kristin Skoland, Heather Kittrell, Justin Brown, Locke Karriker, and Derald J. Holtkamp. "Evaluation of a staged loadout procedure for market swine to prevent transfer of pathogen contaminated particles from livestock trailers to the barn." Journal of Swine Health and Production 29, no. 5 (2021): 234-243. Copyright 2021 American Association of Swine Veterinarians. Posted with permission