Neutering Kittens

Emma Stevenson MA VetMB MRCVS

Veterinary Surgeon

RSPCA Greater Manchester Animal Hospital

Overview

Why neuter cats? Why prior to puberty? The technical bit What about afterwards?

• Population control

– Animal welfare

– Public health

– Environmental

The importance of neutering

• Individual animal

– Reduce disease

– More agreeable pets for rehoming

The importance of neutering

Disease prevention

Mammary neoplasia Ovarian neoplasia Uterine neoplasia Pyometra (8% mortality)

Castration reduces mortality

Road traffic accidents FIV and FeLV Cat bite abscesses

Owned cats >90% owners neuter eventually But 20% have a litter, of which 75% unplanned

>10% of owned elective

cat spays unplanned pregnant 36% of relinquished animals

from unplanned litters

Pregnancy percentage of total monthly cat spays

0

5

10

15

20

25

30

35

40

Owned cats Strays

% p

reg

na

nt

Jan 2012 Jan 2013 Jan 2014

Why neuter prior to puberty?

Population control Shelter space Disease prevention Surgical reasons

Cat spay prior to puberty

Small blood vessels Minimal abdominal fat Predictable anatomy

– Not in oestrus

– Non pregnant

– No pyometra..

When to neuter different populations

Feral cats Shelter cats Owned (charity)

When? Anytime (>300g)

Before adoption

Before puberty

Why? Difficult to recapture

Lack of shelter spacePoor uptake post-adoption

High risk of pregnancy

Anaesthetic considerations

• Selection of candidates

• Age v weight chart

• BSA dosing

• Minimise stress

Anaesthetic Considerations

Hypothermia Hypoglycaemia Cardiovascular Hepatic function Renal function Rapid recovery

'QUAD' Anaesthetic Protocol

Weight (kg) Body Surface area (m²)

Volume of each drug (ml)

0.5 0.06 0.04

1.0 0.10 0.06

1.5 0.13 0.08

2.0 0.17 0.10

Anaesthetic agent Dose

Medetomidine 600 μg/m²

Ketamine 60 mg/m²

Buprenorphine 180 μg/m²

Midazolam 3 mg/m²

Analgesia

Analgesia after feline OVH comparing buprenorphine

or butorphanol, and carprofen or meloxicam, 2012,

J Feline Med Surg, Polson, Taylor & Yates

100 cats, blinded, randomised prospective study All had midazolam-medetomidine-ketamine

anaesthetic All 4 groups- low pain scores, no significant

differences No differences amongst kittens or pregnant cats

Alternative analgesia

Butorphanol Buprenorphine Methadone

Surgical Considerations (spay)

Surgical Considerations (Castration)

Prenatal testicular descent

Delay cryptorchids Standard technique Care with traction BP fold and no

spines

Long term consequences?

Long term outcome of gonadectomy performed at an early age or traditional age in cats, JAVMA, 2000, Howe

Cohort, 263 shelter cats, 3 year follow up Not increase in short term morbidity or mortality No increase in infectious disease, behavioural or

other medical problems (incl FLUTD)

Long term consequences?

Obesity Multifactorial Neutering a risk factor But this is not an inevitable

consequence of neutering!

FLUTD No correlation between

castration and urethral diameter

Diabetes mellitus

Delayed growth plate closure

Conclusions

Low complication

rate v benefit to

individual

Overpopulation is a major welfare issue

Limited evidence base

Mammary neoplasia

Obesity

Overcrowded shelters

Pyometra

Which anaesthetic protocol?