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Pain Management For Piglets During

Castration and Tail Docking

Monique Pairis-Garcia BS, DVM, PhD, mdpairis@iastate.edu Anna Johnson BSc, MSc, PhD, johnsona@iastate.edu

Department of Animal Science,Iowa State University

Ames, IA

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Objectives

• Defining pain

• How to measure pain?

• Regulatory concerns for using pain relieving drugs in the United States

• Case Study: Drug efficacy for pain management during castration

Defining PainPain: “Unpleasant sensory and emotional experience associated with actual or potential tissue damage”1

u Pain and suffering are clinically important conditions adversely affecting an animal’s quality of life (short-term or long-term)

u Prevention and alleviation of animal pain and suffering (i.e., management) are important goals

1IASP, 2004 3

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Procedures Management

Procedures

Disease

Painful Events

• Castration• Tail docking• Teeth

clipping• Reproductive

surgery• Repairs

• Lameness• Shoulder

ulcers• Heal

erosions• Fractures

• Tail/vulva bites• Injuries

• Lameness• Mastitis• Farrowing

difficulties• Respiratory

disease • GI disease

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Procedures Management

Procedures

Disease

Painful Events

• Castration• Tail docking• Teeth

clipping• Reproductive

surgery• Repairs

• Lameness• Shoulder

ulcers• Heal

erosions• Fractures

• Tail/vulva bites• Injuries

• Lameness• Mastitis• Farrowing

difficulties• Respiratory

disease • GI disease

Castration

Tail Docking

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Castration

• Removal of testicles or destruction of testicular formation2

– Prevention of unwanted breeding– Reduced fighting and aggression– Meat quality improvement

• Pain associated with scrotal incision, extraction of the testes and severing of the spermatic cords

2Petherick , 2010Mcglone, 2014

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Tail Docking

• Portion of tail removed– Prevent/Decrease tail biting– Decrease economic loss associated with

reduction in growth performance and increased incidence of infection

• Pain associated withphysical removal3

Liat Romme Thomsen, 2013

3Sutherland et al, 2011

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How to measure pain• Physiological measures– Hormones, Catecholamines, Immune response

• Behavioral measures– Locomotion, postures, maintenance behaviors

• Performance measures

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Physiological Measures

• Hormones– ACTH (Adrenocorticotropic hormone)4

– Cortisol

• Catecholamines– Norepinephrine/Epinephrine5 effects on:

• Heart rate• Glucose levels• Lactate levels

**Physiological measures can also increase due to general arousal and handling**

4Prunier et al, 2005; 5Hay et al 2003

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Physiological Measures

• Immune function6

– Acute phase proteins– Pro-inflammatory cytokines– Antibody response

**May result in greater welfare concerns if animal’s health is compromised**

Wikipedia, 20146Moya et al, 2008

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Behavioral Measures

• Behavioral changes– Locomotion and Posture7

• Head turning toward hindquarters• Hind leg lifting• Slow twitching tail

– Maintenance behaviors8

• Reduced feeding • Reduced drinking• Reduced activity

7Wemelsfeder and van Putten, 1985; 8McGlone and Hellman, 1988

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Vocalization

• Behavioral indicator of pain9

– Immediate vocal response– High frequency calling– Increased calling rate

9Xin et al, 1989

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Performance Measures

• Average daily gain• Feed intake• Market weight• Carcass quality• Mortality

Iowa State University, 2011

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Manage Pain On Farm

Husbandry Techniques

Pharmacological Techniques

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Regulatory Concerns in the U.S.

• Animal drugs intended for use in the U.S are regulated by Food and Drug Administration (FDA) Center for Veterinary Medicine (CVM)10

• There are no pain relieving drugs specifically approved by FDA for use in livestock in the U.S.11

• Extra-label drug use (ELDU) is regulated under the Animal Medicinal Drug Use Clarification Act of 1994 (AMDUCA)

10Smith and Modric, 2013 11Coetzee, 2011

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AMDUCA requirements

• Valid Veterinary-Client-Patient Relationship (VCPR)• Extra-label use limited to circumstances when a threat

is posed to the health of an animal, or when failure to treat results in suffering or death

• FDA approved animal and human drugs• There is no approved product to address the issue• Product administered under the direction of a

licensed veterinarian and assigned an extended withdrawal time to avoid residues.

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Pharmacological• Local Anesthetics– Lidocaine

• General Anesthetics–CO2 Gas– Isoflurane

• Analgesics–NSAIDs

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Local anesthetics

Local• Most commonly used pain relieving drug in

food animal medicine12

• Produces loss of sensation without loss of consciousness by preventing and blocking nerve impulses – Lidocaine/Prilocaine

**Short Acting**12Muir et al, 1995

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Lidocaine

• Lidocaine is commonly suggested as a drug for pain relief during castration and tail docking.

• Lidocaine is NOT APPROVED for veterinary use

• Only Lidocaine approved for humans can legally be prescribed under AMDUCA and used in an extra-label manner

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General Anesthetics

• Loss of feeling or sensation• State of unconsciousness with absence of

pain sensation• Suppresses cerebral activity– Co2

– Isoflurane– Sevoflurane

**Short Acting**

AnalgesicsNon-steroidal anti-inflammatory drugs (NSAIDs)

Flunixin meglumine

Meloxicam

Ketoprofen

**Longer acting but take time to have an effect**

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Case Study: Pain relief for castration

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Materials and Methods

• 141 litters• Four male piglets/ litter• Four treatments– Castration alone (C) – Castration + Meloxicam (M)– Castration + Lidocaine (L)– Castration + Lidocaine + Meloxicam (LM)

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Production Measures

• Mean weight on castration day was not different.

• No difference in weight gain • 11% morbidity with no treatment effect• 5% mortality with no treatment effect

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Case Summary

• Lidocaine reduced pain during castration• Meloxicam reduced pain after castration• No treatment effects on:– Skin temperature, weight gain, morbidity or

mortality• Herdsmen effectively administered local

anesthesia

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Take home points

• Pain associated with castration and tail docking is a current welfare issue on farm

• Pain relief may be conducted using either anesthetics, analgesics or a combination of both

• Use of these drugs in an extra label manner is approved under AMDUCA

• Multi-modal drug approach is most effective for pain relief

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THANK YOU VERY MUCH FOR YOUR ATTENTION

QUESTIONS?