Reproductive performance of Thoroughbred mares in the Waikato region of New Zealand: 1. Descriptive analyses.
N Z Vet J
; 60(6): 329-34, 2012 Nov.
Article
en En
| MEDLINE
| ID: mdl-22905831
ABSTRACT
AIM:
To describe the reproductive performance of a population of Thoroughbred mares on stud farms in the Waikato region of New Zealand.METHODS:
A prospective cohort study was performed involving five stud farms in the Waikato region of New Zealand during three consecutive breeding seasons (2006-2008). A total of 1,482 individual mares contributed 2007 mare years and 3,402 oestrous cycles over the three breeding seasons. Mares were served by 87 individual stallions.RESULTS:
The mean first-cycle pregnancy rate (FCPR) was 53.6%, the end-of-season pregnancy rate (SPR) was 85.3% and the foaling rate was 80.2%. There were significant differences amongst farms for FCPR (range 47.3-68.2%; p<0.01), SPR (range 81.4-92.6%; p<0.001) and foaling rate (range 77.8-90.1%; p<0.001). There were significant differences amongst stallions in their FCPR (range 38-74%; p<0.001) and SPR (range 72-97%; p<0.001).The proportion of pregnancies lost between day 14-16 and day 42 of gestation was 5.5% and the proportion of pregnancies lost between day 42 and term was 3.0%. Mares older than 14 years of age and barren mares had the highest pregnancy loss rates. Of all pregnancies diagnosed at 14-16 days, 12.9% were multiple pregnancies. The length of the breeding season was relatively short with 87.3% of services occurring in the 91-day period between 1 September and 30 November.CONCLUSIONS:
The reproductive performance of Thoroughbred mares in the Waikato region of New Zealand was similar to that reported from other major Thoroughbred breeding countries. Although the per-cycle pregnancy rates in this study were lower than those reported in some studies, the foaling rate was similar to previous reports and this was achieved during a relatively short breeding season.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Preñez
/
Índice de Embarazo
/
Caballos
Tipo de estudio:
Etiology_studies
/
Incidence_studies
/
Observational_studies
/
Risk_factors_studies
Límite:
Animals
/
Pregnancy
País/Región como asunto:
Oceania
Idioma:
En
Revista:
N Z Vet J
Año:
2012
Tipo del documento:
Article
País de afiliación:
Nueva Zelanda