Monique D. Pairis-Garcia

Validation of a lameness model in sows using physiological and mechanical measurements

The objective of this study was to develop a validated, transient, chemically induced lameness model in sows using subjective and objective lameness detection tools. Experiment 1 determined an effective joint injection technique based on volume and placement of dye using feet collected from 9 finisher pigs and 10 multiparity cull sow carcasses. Experiment 2 confirmed the injection technique in live animals and produced a transient clinical lameness in 4 anesthetized sows injected with amphotericin B (15 mg/mL) in the distal interphalangeal joints of the claw. Clinical lameness was assessed by a categorical lameness scoring system, and a postmortem visual confirmation of joint injection technique was obtained. In Exp. 3, 6 sows were injected with 0, 10, or 15 mg/mL amphotericin B in either the left or right hind foot and were monitored until clinical resolution. Treated sows demonstrated elevated clinical lameness scores. These changes resolved by 7 d after lameness induction. Control sows injected with sterile saline developed a clinical lameness score of 0.5, which resolved 72 h post injection. In Exp. 4, 36 sows were injected with 10 mg/mL amphotericin B in 1 of 4 injection sites (left front claws, right front claws, left rear claws, and right rear claws). All injected sows exhibited a decrease in maximum pressure, stance time, and number of sensors activated on the GaitFour (P < 0.05) sensor system. A static force plate also demonstrated a decrease in weight (kg) being placed on the injected foot when all feet were injected (P ≤ 0.05). Injection of amphotericin B induced a predictable acute lameness that resolved spontaneously and is an effective method to model lameness in sows.

Pharmacokinetics of meloxicam in mature swine after intravenous and oral administration

The purpose of this study was to compare the pharmacokinetics of meloxicam in mature swine after intravenous (i.v.) and oral (p.o.) administration. Six mature sows (mean bodyweight ± standard deviation = 217.3 ± 65.68 kg) were administered an i.v. or p.o. dose of meloxicam at a target dose of 0.5 mg/kg in a cross-over design. Plasma samples collected up to 48 h postadministration were analyzed by high-pressure liquid chromatography and mass spectrometry (HPLC-MS) followed by noncompartmental pharmacokinetic analysis. Mean peak plasma concentration (CMAX ) after p.o. administration was 1070 ng/mL (645-1749 ng/mL). TMAX was recorded at 2.40 h (0.50-12.00 h) after p.o. administration. Half-life (T½ λz ) for i.v. and p.o. administration was 6.15 h (4.39-7.79 h) and 6.83 h (5.18-9.63 h), respectively. The bioavailability (F) for p.o. administration was 87% (39-351%). The results of this study suggest that meloxicam is well absorbed after oral administration.

Measuring the efficacy of flunixin meglumine and meloxicam for lame sows using a GAITFour pressure mat and an embedded microcomputer-based force plate system.

Pain associated with lameness on farm is a negative affective state and has a detrimental impact on individual farm animal welfare. Animal pain can be managed utilizing husbandry tools and through pharmacological approaches. Nonsteroidal anti-inflammatory drugs including meloxicam and flunixin meglumine are compounds used in many species for pain management because they are easy to administer, long lasting, and cost-effective. Assessing an animals biomechanical parameters using such tools as the embedded microcomputer-based force plate system and GAITFour pressure mat gait analysis walkway system provides an objective, sensitive, and precise means to detect animals in lame states. The objectives of this study were to determine the efficacy of meloxicam and flunixin meglumine for pain mitigation in lame sows using the embedded microcomputer-based force plate system and GAITFour pressure mat gait analysis walkway system. Lameness was induced in 24 mature mixed-parity sows using a chemical synovitis model and compared 3 treatments: meloxicam (1.0 mg/kg per os), flunixin meglumine (2.2 mg/kg intramuscular) and sterile saline (intramuscular). Weight distribution (kg) for each foot was collected twice per second for a total of 5 min for each time point using the embedded microcomputer-based force plate system. Stride time, stride length, maximum pressure, activated sensors, and stance time were collected using 3 quality walks (readings) for each time point using the GAITFour pressure mat gait analysis walkway system. Sows administered flunixin meglumine or meloxicam tolerated more weight on their lame leg compared with saline sows (P < 0.005). Sows administered flunixin meglumine or meloxicam had smaller differences in stance time, maximum pressure, and activated sensors between the sound and lame legs compared with saline-treated sows between 37 and 60 h after lameness induction (P < 0.03). In conclusion, flunixin meglumine and meloxicam administration mitigated pain sensitivity in sows after lameness induction when pain sensitivity was evaluated with the embedded microcomputer-based force plate system and GAITFour pressure mat gait analysis walkway system. Analgesic drugs may be a key tool to manage negative pain affective states associated with lameness.

Sow behavioral responses to transient, chemically induced synovitis lameness

Abstract The objective was to determine behavioral changes when sows were induced lame using this chemical synovitis model. Twenty-three multiparous, non-pregnant sows were compared during lame and non-lame states. Behavior was recorded over three days. Seven behaviors (foraging, drinking, standing, sitting, sternal and lateral lying) and three locations (drinker, home pen and feed bunk) were recorded. Observations of sows drinking, standing, lying sternal and being in the drinker location decreased after induction. Lying lateral frequency, regardless of side, increased after sows were induced lame. Frequency in the home pen location increased, but no differences were observed for feed bunk location after sows were induced lame. The induced lame foot had no observed effect on lying side preference. By the end of the round, all behavioral and location frequencies returned to baseline levels. Standing, lying and drinking frequencies seem to be promising sow behavioral tools when transitioning from sound to lame states.

Teaching Tip: The Development of an Interactive Computer-Based Training Program for Timely and Humane On-Farm Pig Euthanasia

With extensive knowledge and training in the prevention, management, and treatment of disease conditions in animals, veterinarians play a critical role in ensuring good welfare on swine farms by training caretakers on the importance of timely euthanasia. To assist veterinarians and other industry professionals in training new and seasoned caretakers, an interactive computer-based training program was created. It consists of three modules, each containing five case studies, which cover three distinct production stages (breeding stock, piglets, and wean to grower-finisher pigs). Case study development was derived from five specific euthanasia criteria defined in the 2015 Common Swine Industry Audit, a nationally recognized auditing program used in the US. Case studies provide information regarding treatment history, clinical signs, and condition severity of the pig and prompt learners to make management decisions regarding pig treatment and care. Once a decision is made, feedback is provided so learners understand the appropriateness of their decision compared to current industry guidelines. In addition to training farm personnel, this program may also be a valuable resource if incorporated into veterinary, graduate, and continuing education curricula. This innovative tool represents the first interactive euthanasia-specific training program in the US swine industry and offers the potential to improve timely and humane on-farm pig euthanasia.

Development and refinement of a technique for short-term intravascular auricular vein catheter placement in mature sows.

Intravenous drug administration in adult swine is difficult to perform due to inaccessible superficial veins and thick subcutaneous fat layers. However, successful intravenous drug administration is critical for many biomedical applications including pharmacokinetic studies as extravascular drug administration can influence the drug’s absorption and elimination rate. The purpose of this study was to develop and refine an effective technique for indwelling auricular vein catheter placement in the conscious mature sow. We developed a protocol using a topical anesthetic cream and minimal physical restraint to place indwelling catheters in the auricular vein of six multiparous sows. This method was quick (3 min 20 s ± 8 s [mean ± SE per catheter]), effective (11/12 catheters successfully placed) and reliable, allowing a large drug volume (20–22 mL) to be administrated successfully during the trial without relying on prolonged restraint or general anesthesia of the sow.

Caretaker attitudes toward swine euthanasia1

Abstract Timely euthanasia is a fundamental part of safeguarding swine welfare by reducing suffering when compromised pigs are unable to recover. The quality and appropriateness of timely euthanasia rely mainly on the knowledge and experience of the individual caretaker but may also be affected by caretaker attitudes toward euthanasia. However, literature on caretaker attitudes toward swine euthanasia is lacking. This study investigated caretaker attitudes, perceived knowledge, and confidence in performing on-farm timely euthanasia. A total of 84 caretakers from eight swine farms (ranging in size from 1,300 to 7,000 sows) participated in a survey designed to investigate attitudes toward swine and swine euthanasia. Caretaker’s ages ranged from 18 to 59 yr with an average work experience of 8.5 yr. The majority of participants worked in either farrowing or breeding units. Survey questions were designed to assess caretakers’ attitudes and attributes (empathy affect, empathy attribution, attitudes toward pigs, feeling bad about euthanizing pigs, and assumptions about pigs’ emotional capabilities), decision-making skills (confidence in identifying compromised pigs or relying on coworkers to make decisions), and euthanasia skillset (confidence in performing euthanasia, training, and perceived level of knowledge). Using cluster analysis to analyze survey answers, three distinct groups of caretakers were identified: 1) confident and empathetic; 2) Confident, knowledgeable, and detached; and 3) unconfident and lacking knowledge. The survey results showed that empathy attribution was strongly correlated with empathy affect (r = 0.571, P < 0.01) and that empathy affect and empathy attribution were higher in female caretakers compared with male caretakers (P < 0.05). A risk analysis that included previously identified clusters showed that females were more likely to be grouped among caretakers that were confident and empathetic (P = 0.04), and caretakers with more than 2 yr of swine experience were more likely to be grouped as confident and skilled (P = 0.01), while the unconfident and empathetic were more likely to have had less than 2 yr of experience (P = 0.04). This study provides important information about variability in caretaker experience as well as their attitudes toward pigs and timely euthanasia. Increased knowledge about swine caretaker attitudes may be used to implement training and euthanasia protocols to increase both human and pig welfare on farm.

Technical note: Instantaneous sampling intervals validated from continuous video observation for behavioral recording of feedlot lambs1

When considering methodologies for collecting behavioral data, continuous sampling provides the most complete and accurate data set whereas instantaneous sampling can provide similar results and also increase the efficiency of data collection. However, instantaneous time intervals require validation to ensure accurate estimation of the data. Therefore, the objective of this study was to validate scan sampling intervals for lambs housed in a feedlot environment. Feeding, lying, standing, drinking, locomotion, and oral manipulation were measured on 18 crossbred lambs housed in an indoor feedlot facility for 14 h (0600-2000 h). Data from continuous sampling were compared with data from instantaneous scan sampling intervals of 5, 10, 15, and 20 min using a linear regression analysis. Three criteria determined if a time interval accurately estimated behaviors: 1) ≥ 0.90, 2) slope not statistically different from 1 ( > 0.05), and 3) intercept not statistically different from 0 ( > 0.05). Estimations for lying behavior were accurate up to 20-min intervals, whereas feeding and standing behaviors were accurate only at 5-min intervals (i.e., met all 3 regression criteria). Drinking, locomotion, and oral manipulation demonstrated poor associations () for all tested intervals. The results from this study suggest that a 5-min instantaneous sampling interval will accurately estimate lying, feeding, and standing behaviors for lambs housed in a feedlot, whereas continuous sampling is recommended for the remaining behaviors. This methodology will contribute toward the efficiency, accuracy, and transparency of future behavioral data collection in lamb behavior research.

Flooring preference and behavior in sound and lame sows

ABSTRACT The objectives of this study were to assess sow flooring preference and behavior during sound, induced lame and lameness recovery states. Thirty-four multiparous, non-pregnant sows were compared prior to and following lameness induction (day 0). Behavior was recorded on six days (days −1, +1, +2, +3, +4 and +10). Three flooring locations (Alley, Concrete and Mat) and four behaviors (lying lateral, lying sternal, sitting and standing) were recorded. Sows increased Mat frequency and decreased Alley frequency on day +1 (most lame) relative to day −1. Lying lateral frequency increased, whereas lying sternal and standing frequencies decreased between day −1 and day +1. Sows appear to prefer the Mat within 24 h following lameness induction. Lying lateral is likely a more comfortable position than standing or lying sternal in these lame sows. In conclusion, these behaviors may be reliable indicators to further ascertain if a sow is lame.