A comparison between cervical dimensions of pregnant and nonpregnant Santa Gertrudis and Bos taurus cows

Cervical measurements were recorded on palpation per rectum for 603 Bos taurus , Santa Gertrudis, and crossbred cattle. Postmortem cervical measurements were recorded for 77 of these cows. Antemortem measurements were positively correlated with those taken at postmortem examination (cervical diameter: r=0.75, P<0.01 and cervical length: r=0.29, P<0.06). Cervical diameters from antemortem and postmortem specimens were greater in Santa Gertrudis cattle than in Bos taurus and crossbred cattle (P<0.05). Cervical shape was different between Santa Gertrudis cattle and Bos taurus or crossbred cattle (P<0.01), with Santa Gertrudis cows having a higher incidence of conical shaped cervices than other breeds. Within Santa Gertrudis cattle, the incidence of conical cervical shape increased with age (P<0.05). Conical cervical shape was associated with a lower pregnancy rate in all breeds (P<0.01). Within Santa Gertrudis cattle, conical cervical shape was associated with a lower pregnancy rate in 1- to 4-year-old cows (P<0.05) but not in cows more than 4 years of age (P>0.05).