Investigation into udder characteristics, mastitis and milk production in crossbred sheep

Abstract

Associations between udder characteristics, milk yield, milk somatic cell counts (SCC) and prevalence of mastitis were evaluated in 121 twin-suckled crossbred non-dairy ewes at four, eight and twelve weeks after parturition. Overall, milk production decreased with time, being 1.09 ± 0.04 litres per four hours at week four of lactation, 0.68 ± 0.02 litres at week eight and 0.48 ± 0.01 litres at week twelve with corresponding mean SCC of 0.32 x 10⁶ cells mL⁻¹, 0.39 x 10⁶ cells mL⁻¹ and 0.28 x 10⁶ cells mL⁻¹, respectively. Incidence of mastitis was 12.7%, 9.8% and 8.9% for weeks 4, 8 and 12, respectively. Of the 20 individuals that displayed SCC indicative of mastitis, only 5 had elevated SCC at more than one sampling time. No consistent association was observed between SCC and visual scores for udder depth, udder distention, degree of separation or teat placement (P>0.05 for all). Milk volume and weight of lamb was greater for ewes with an udder depth of 3 compared with 4 with no other associations evident (P>0.05). Overall, the incidence of subclinical mastitis was low but present in this flock with the udder characteristics assessed here providing poor indicators of either mastitis or milk production.