Effect of somatic cell count level on functional longevity in Valle del Belice dairy sheep assessed using survival analysis

Valentina Riggio, Baldassare Portolano, Riggio, Henk Bovenhuis, Van Arendonk, Maizon

Risultato della ricerca: Articlepeer review

10 Citazioni (Scopus)

Abstract

The objectives of this study were to evaluate the effect of somatic cell count (SCC) on functional longevity and to estimate the heritability of functional longevity using survival analysis in Valle del Belice dairy sheep. A total of 4,880 lactations of 2,190 ewes from 11 flocks were used. In this study, SCC was considered as an indication of subclinical mastitis. In case of clinical cases, identified by the technicians at milking time, test-day weights and milk samples of those ewes were not considered. Somatic cells were analyzed as counts, without any transformation, and were grouped in 3 classes based on the observed SCC maximum (mxSCC). The mxSCC classes, expressed as 103 cells/mL, were classified as 1 if mxSCC ≤ 500, 2 if 500 < mxSCC < 1,000, and 3 if mxSCC ≥ 1,000. An increase in SCC was associated with an increased hazard of being culled. Ewes in the highest class of SCC on a test-day had a 20% higher hazard of being culled than those in the lowest class. Therefore, SCC played a role in culling decisions of Valle del Belicedairy sheep farmers. The heritability estimate for functional longevity was 7% on the logarithmic scale and 11% on the real scale, indicating that selection for thistrait is possible in sheep. The flock-year-season effect explained 19% of the variation on the logarithmic scale and 27% of the variation on the real scale.
Lingua originaleEnglish
pagine (da-a)6160-6166
Numero di pagine7
RivistaJournal of Dairy Science
Volume92
Stato di pubblicazionePublished - 2009

All Science Journal Classification (ASJC) codes

  • Food Science
  • Animal Science and Zoology
  • Genetics

Fingerprint Entra nei temi di ricerca di 'Effect of somatic cell count level on functional longevity in Valle del Belice dairy sheep assessed using survival analysis'. Insieme formano una fingerprint unica.

Cita questo