ICAWC 2014 Istanbul - Emma talks about pre-pubertal neutering of cats.

1. Neutering Kittens
Emma Stevenson MA VetMB MRCVS
Veterinary Surgeon
RSPCA Greater Manchester Animal Hospital

2. Overview
 Why neuter cats?
 Why prior to puberty?
 The technical bit
 What about afterwards?

3. The importance of neutering
• Population control
– Animal welfare
– Public health
– Environmental
• Individual animal
– Reduce disease
– More agreeable pets
for rehoming

4. The importance of neutering

5. Disease prevention
 Mammary neoplasia
 Ovarian neoplasia
 Uterine neoplasia
 Pyometra (8% mortality)
 Castration reduces
mortality
 Road traffic accidents
 FIV and FeLV
 Cat bite abscesses

6. 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

7. Pregnancy percentage of total
monthly cat spays
40
35
30
25
20
15
10
5
0
Owned cats Strays
% pregnant
Jan 2012 Jan 2013 Jan 2014

8. Why neuter prior to puberty?
 Population control
 Shelter space
 Disease prevention
 Surgical reasons

9. Cat spay prior to puberty
 Small blood vessels
 Minimal abdominal fat
 Predictable anatomy
– Not in oestrus
– Non pregnant
– No pyometra..

10. 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
space
Poor uptake
post-adoption
High risk of
pregnancy

11. Anaesthetic considerations
• Selection of candidates
• Age v weight chart
• BSA dosing
• Minimise stress

12. Anaesthetic Considerations
 Hypothermia
 Hypoglycaemia
 Cardiovascular
 Hepatic function
 Renal function
 Rapid recovery

13. 'QUAD' Anaesthetic Protocol
Anaesthetic agent Dose
Medetomidine 600 μg/m²
Ketamine 60 mg/m²
Buprenorphine 180 μg/m²
Midazolam 3 mg/m²
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

14. 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

15. Alternative analgesia
 Butorphanol
 Buprenorphine
 Methadone

16. Surgical Considerations (spay)

17. Surgical Considerations
(Castration)
 Prenatal testicular
descent
 Delay cryptorchids
 Standard technique
 Care with traction
 BP fold and no
spines

18. 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)

19. 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

20. Conclusions
Low complication
rate v benefit to
individual
Limited evidence base
Overpopulation
is a major welfare issue
Mammary neoplasia
Obesity
Overcrowded shelters
Pyometra
Which anaesthetic protocol?