Effect of Carprofen and CIDR on pregnancy rates in dairy cattle

Abstract

The effects of carprofen and/or a CIDR administered 14 days afterartificial insemination (AI) on pregnancy rates (PR) in lactating dairycattle were investigated. Following detection of corpus luteum (CL) byultrasonography (USG) 14 days after AI, cows were randomlyallocated to four groups. I) Carprofen (1.4 mg/kg; RimadylÒ, ZoetisAnimal Health) was administered. II) CIDRÒ(Zoetis Animal Health)was inserted for seven days. III) Carprofen and CIDR were admin-istered as in Groups I and II. Group IV served as untreated controls.Cows were examined for CL 21 days after AI, and cows with CL wereassumed to be possibly pregnant. Pregnancies were diagnosed withUSG and palpation per rectum 28–32 and 55–60 days after AI,respectively. Significant differences (p<0.05) indicated that cows inGroups I (168/211; 79.6%) had 1.5 (0.9–2.5), II (198/231; 85.7%) had2.2 (1.3–3.7), III (172/216; 79.6%) had 1.3 (0.8–2.2) times higher chance to have CL than those in Group IV (149/199; 74.9%) 21 daysafter AI. PR at 28–32 days in Groups I (103/212; 48.6%), II (118/233;50.6%), III (103/217; 47.5%), IV (89/199; 44.7%) and 55–60 days inGroups I (99/213; 46.5%), II (111/233; 47.6%), III (97/217; 44.7%), IV(84/199; 42.2%) did not differ. Pregnancy loss between days 21 and 28–32 in Groups I (66/168; 39.3%), II (81/198; 40.9%), III (73/172;42.4%), IV (62/149; 41.6%) and between days 28–32 and 55–60 inGroups I (4/103; 3.9%), II (7/118; 5.9%), III (6/103; 5.8%), IV (6/89;6.7%) did not differ. In conclusion, no effects of carprofen and/orCIDR administered 14 days following AI on PR were observed inlactating dairy cattle despite higher CL incidence 21 days after AI.