Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108
Performing Department
Veterinary Population Medicine
Non Technical Summary
Disbudding of goat kids is a common husbandry procedure in the dairy goat industry. Producers often carry out this procedure in the first week of life using a hot cautery iron without the application of pain relief. The goal of this proposal is to develop a practical and efficacious pain management strategy for disbudding neonatal goat kids. In specific aim 1, we will monitor changes in plasma biomarkers and behaviors to assess pain responses to 3 different multimodal analgesic strategies in comparison to single modality pain control for disbudding neonatal goat kids. In specific aim 2, the analgesic approach identified to result in the lowest pain response(from specific aim 1) will be applied to a cohort of commercial dairy kids to investigate the long-term effects of pain control as compared to the current standard of care (no pain relief) in the industry. Results of this work will improve the welfare of goat kids by providing producers with practical on-farm pain management strategies.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
Specific Aim 1 (year 1): To determine the effect of practical multimodal pain management on the acute pain response associated with disbudding in neonatal goat kids. We hypothesize that multimodal pain management will result in a reduction in both plasma biomarkers and behaviors associated with pain as compared to goat kids that receive single modality pain management.Specific Aim 2 (year 2): To investigate the effect of multimodal pain management on disbudding and the subsequent health and performance of pre-weaned goat kids in a commercial dairy goat farm setting. We hypothesize that multimodal pain management for disbudding of goat kids will improve health and performance through the pre-weaning period as compared to disbudding without pain management.
Project Methods
MethodsYear 1: Study Site and Kid Management: This study will be conducted in the spring of 2019 (kidding season) in the Large Animal Teaching Barn located at the University of Minnesota, College of Veterinary Medicine (St. Paul, MN). Daily husbandry and management of goat kids will follow the standards outlined in the FASS Guide for the Care and Use of Agricultural Animals in Research and Teaching. Veterinary and undergraduate student workers trained in goat care will be responsible for all goat kid feeding, study observations, and study related activities. Daily observations will be performed by RAR (Research Animal Resources) staff and by W. Knauer (PI). Kids will be fed milk replacer (Doe's Match, Land O'Lakes Animal Nutrition, Shoreview, MN) through a mob feeder at a rate of 20% body weight per day split into three feedings.Kid Enrollment: A total of 42 male goat kids between 2 and 4 days of age will be purchased from a local goat dairy (40 miles away from the CVM) and transported by study personnel to the study site. Kids will be examined by study PIs (Drs. Knauer and Barrell) and will be excluded if they have physical exam abnormalities, are unable to stand on their own, or are otherwise unthrifty. Kids will be individually identified with ear tags upon arrival to UMN, and housed in group pens of seven (one kid from each treatment group per pen), and allowed to acclimate for 3d prior to disbudding. Kids will be randomly assigned to one of seven treatment groups via block randomization (6 blocks, 7 kids per block):Simulated Disbudding (SHAM)Xylazine (X) (0.1 mg/kg IM)Oral Meloxicam (M) (1mg/kg PO)Buffered Lidocaine (L) (5 mg/kg SQ)Buffered Lidocaine + Xylazine (XL)Oral Meloxicam + Xylazine (XM)Oral Meloxicam + Xylazine + Lidocaine (XML)Disbudding Procedure: All kids will undergo disbudding (or simulated disbudding [SHAM] within three sequential working days between the ages of 5 and 7d. Kids will be fed their morning milk feeding (6AM), and then study procedures will commence 2 hours later (8AM). X, L, M, XL, XM, and XML kids will receive their treatments 20 minutes prior to disbudding by a trained study technician. Xylazine will be administered to X, XL, XM and XML kids at a dose of 0.1 mg/kg in the epaxial muscles with a 25g needle. Lidocaine will be buffered in a 1:9 dilution with 8.4% sodium bicarbonate and administered at a dose of 5 mg/kg, diluted to a total volume of 4ml with sterile water into a 6 ml syringe, and placed over the cornual branches of the lacrimal and infratrochlear nerves on both sides of the head at a dose of 1ml per site using a 25g needle. Lidocaine will be administered to XL and XML kids after they have been sedated. Meloxicam tablets will be administered orally at a dose of 1 mg/kg. All kids, including the SHAM group, will be shorn over their horn buds and both jugular veins with electric clippers at -20min, prior to administration of treatments. Thermal disbudding will be performed by the same trained individual, blinded to treatment, for all kids with the use of a Rhinehart X50 disbudding iron (Rhinehart Development, Spencerville, IN). Briefly, kids will be securely manualy, and the hot iron applied to each horn bud for no more than 3 seconds at a time per bud. The head will be allowed to fully cool in between hot iron applications, and the procedure will be considered complete when there is a copper ring of cauterized skin that does not rub off with a fingernail. SHAM kids will undergo the same process except that the disbudding iron will be cold.Data Collection: Blood samples and behavioral observation data will be collected before, during and after disbudding for all treatments. A 3 ml blood sample will be taken from the jugular vein into a 5 ml refrigerated tube containing anti-coagulant before (at -20, -10 and -1 min) and after (at 1, 10, 20 and 30 min, and then at 1, 2, 4, 6, 12, 24, 36 and 48 hours) disbudding. Blood samples will be refrigerated after collection. Plasma will be separated and shipped on ice to the laboratory of Dr. Hans Coetzee (Kansas State University, Manhattan, KS) where prostaglandin E2 (PGE2; pg/mL, Fraccaro et al., 2013), and plasma cortisol concentrations will be determined using a commercial RIA kit (Coat-A-Count Cortisol; Siemens Medical Solutions Diagnostics, Los Angeles, CA). During the disbudding procedure, a second trained individual record incidence of vocalizations and struggling-related behaviors. Additional behavioral data will be collected at 10 min and 1, 2, 6, 12, 24, 36, and 48hrs after the procedure by the same observer. Each goat kid will be observed for 10 minutes during those time points, and frequency of the following behaviors will be recorded: allogrooming, body shaking, ear biting, head butting, head rubbing, head scratching, head shaking, ear flicking, back arch, jumping, running, self-grooming, standing, and lying (Adapted from ethogram described by Hempstead (2017) and Duffield (2010) see Table 1). Mechanical nociceptive threshold testing will be measured via pressure algometry using a calibrated vonFrey anesthesiometer ( Wagner Pain Test FPIX Digital Algometer, Wagner Instruments, Riverside, CT) that has been described for dairy calves but not yet for goat kids (Espinoza et al, 2015). So as to not interfere with behavioral measures, algometry will be performed immediately after disbudding, at 0.5 and 4 hours at a single location associated with each horn bud (Figure 2). Daily body weight (kg) will also be measured each morning throughout the study using a digital scale (Premier 1 Supplies, Washington, IA). Kids leave the study at 48hrs post disbudding.Year 2: Study Site: This study will be conducted in the spring of 2020 during kidding season on a 9,000 head goat dairy (Drumlin Dairy, Chilton, WI) representing the predominant dairy breeds. Kids will be subject to the management practices on the dairy with the exception of the disbudding protocol. The dairy will agree to keep detailed newborn and kid treatment records, adhere to study protocols, and to allow a study technician to visit the dairy weekly for study related activities.Kid Enrollment and Assignment to Treatment Group: A total of 500 healthy goat kids between post-natal days 3 to 7 will be enrolled and assigned to one of two treatment groups:CON: Standard of care for the dairy (thermal disbud with no pain control)TRT: The treatment from specific aim 1 that yielded the lowest overall measures of physiological and behavioral pain-associated behaviors.Individual kids will be systematically randomized based on ear tag number (odd = CON, n = 250; even = TRT; n = 250) and blocked by sex. All kids will be disbudded and treatments administered by trained study personnel using the procedures described in Sp. Aim 1. Kids will exit the study after 6 weeks of follow up.Data Collection: A team of study technicians will visit the farm at the time of disbudding, and then weekly thereafter. Disbudding will be completed by trained technicians for both treatment groups. During disbudding, a study technician will time the procedure from the time the goat kids gets its initial treatment to the time it is placed back into its home pen for both treatment groups. A second trained individual will record incidence of vocalizations and struggling-related behaviors. Kids will be weighed at birth by farm workers, then weekly throughout the study period by study technicians. Furthermore, study technicians will perform weekly health scoring based on the University of Wisconsin Calf Health Scoring App, which will be adapted to goat kid health by Drs. Barrell and Knauer. At each visit, study technicians will collect health treatment records from farm personnel.Data AnalysisStatistical Analysis for both Y1 and Y2 objectiveswill be performed as detailed in the proposal attached to this REEport submission.