بررسی وضعیتهای غیرطبیعی جنین و عوامل کمک کننده در سخت زایی گاوهای شیری نژاد هلشتاین

Objective: 1- Survey of dystocia due to Maipresentation, Malposition
and Malposture of fetus during calving 2- The effect of factors
contributing to dystocia due to fetal Malpresentaion, Malposition and Malposture such as age and number of parturition of dam,
season of parturition sex and weight of calves.
Cases: A total of2 140 single calvings.
Design: Cross sectional prospective. Methods: Fetal presentation, position and posture are used to
indicate the condition of calving. In a normal calving, the presentation
position and posture are: Anterior- longitudinal, dorso- sacral and
extended posture, respectively. During 4 years survey (1988- 1992) 2140 singlecalvingswererecordedandusedto analyzetheconlation between the fetal disposition due to the above fetal condition and age and number of parturition of dam season of parturition, sex and
weight of calves.
Statistical method: The data were analyzed by using Chi- square statistical method. Results: There were 108(5.04%) faulty presentation, position and
posture out of 2140 calvings. The incidence of malpresentation,
malposition and malposture were 3.27%, 0.09% and 1.68%,
respectively. Posterior- longitudinal (No: 70, 3.27%), Dorso pubis (No: 2, 0.09%) and lateral head deviation (No: 18, 0.84%) were
the highest Malpresentaion, Malposition and Malposture,
respectively. Dams with 2 years old had the highest faulty disposition (3 1.48%) whereas it was observed that the 6 year old dams had the lowest (5.5%).The highest fetal disposition were observed in the
first number of calving (3 1.42%) and the lowest was in the 5th parturition. It was observed that 65(5.94° o) male calves out of 1094 calving and 43(3.11%) out of 1046 calving had faulty condition. The average weight of calves with normal condition for male and
female calves were 41.52 and 39.22 Kgs, respectively. But, calves
with Maipresentation, Malposition and Malposture were 40.92, 50.3 and 53.3 Kgs for male calves whereas 39.39. 31.29 and 35.36 Kgs for female calves, respectively. The most abnormal conditions
were in winter (28.7%) and the lowest (25.92%) were in autumn. Conclusions: There were no significant differences between fetal
disposition and age of dam, parturition No. of dam, season of
calving and weight of calves.