Incidence risk and clinical features of retention of foetal membranes in ewes in 28 flocks in southern Greece.
In a field investigation of 28 flocks in southern Greece, 7660 lambings were monitored. Retention of foetal membranes (defined as failure to expel the foetal membranes within 6 h of lambing the last lamb) was recorded in 92 ewes. The median within-flock incidence risk was 1.25% (range: 0-1.9%). The heterogeneity of the risk among flocks was not significant (p = 0.99); no correlation was found between the incidence risk and the flock size (r(sp) = 0.33, p = 0.09). Overall, the median duration of retention was 72 h (range: 9-288 h); it did not differ among flocks (p = 0.89) and was not correlated with flock size (r(sp) = 0.24, p = 0.27). During the initial stage of retention the membranes were fleshy and humid; the cotyledons were thick and congested. Progressively, the membranes became thin, dry and stringy; the cotyledons shrunk and were pale. Finally the membranes dropped as a mass. In ewes with retention for >12 h, a variety of accompanying signs was recorded: straining (in 22% of the ewes with retention), vulval oedema and reddening (in 16%), anorexia (in 13%), recumbency (in 13%) and increased temperature (in 12%) were the most frequent ones. Overall, the median clinical score of the disorder was '2' (range: '1'-'5'); it did not differ among flocks (p = 0.98) and was not correlated with flock size (r(sp) = 0.26, p = 0.25). In 4% of the ewes with retention for <4 days accompanying signs were recorded (median clinical score: '2'), whilst in 80% of the ewes with retention for > or =4 days accompanying signs were recorded (median clinical score: '3'). This difference in the prevalence of clinical signs was significant (p < 0.0001).
Fthenaki
G C
GC
Veterinary Faculty, University of Thessaly, Karditsa, Greece. gcf@vetuth.gr
Leontides
L S
LS
Amiridis
G S
GS
Saratsis
P
P
D000822:Animal Husbandry; D000818:Animals; D005321:Extraembryonic Membranes; D005260:Female; D015994:Incidence; D018457:Placenta, Retained / Q000453:epidemiology / Q000662:veterinary*; D011247:Pregnancy; D018570:Risk Assessment; D012756:Sheep / Q000502:physiology*; D012757:Sheep Diseases / Q000503:physiopathology*; D013030:Spain / Q000453:epidemiology