The Influence of Age, Breed, Rearing Intensity and Exercise on The Incidence of Spavin in Swedish Dairy Cattle

Abstract

The hocks of tied cows of a Swedish dairy herd of different breeds were radiographed. Osteoarthrosis of the arthrodial joints (spavin) was found in 37 % of the animals. Changes were seen before the cows were 2 years old, and they increased in severity with increasing age. Macroscopic and histologic examination revealed that there was osteoarthrosis also in many radiologically normal hocks. The study shows that the frequency of spavin in tied dairy cows is higher than clinical signs indicate. Apparently only cows with fusion of the arthrodial joints show the stiff hind leg movements considered typical of spavin. Differences in the incidence of spavin were found between the different breeds. Cows of the Swedish Friesian breed had the lowest (20%) and cows of the Jersey breed had the highest (50%) incidence of spavin. However, as regards the Jersey breed this was due to the high incidence (71%) found in cows raised on a high intensity feeding during the young stock period. Among the SJB cows raised on a normal intensity feeding the incidence of spavin was 25 %. Such a relationship between high young stock feeding intensity and the incidence of spavin was not seen within the other breeds. The cows in another herd with loose housing had a lower frequency of spavin than the tied cows. Offspring of animals with spavin had a higher incidence of spavin than the offspring of animals without spavin.

Sammendrag

En radiologisk undersökning av haslederna utfördes på uppbundna kor av olika raser i en svensk mjölkkobesättning. Osteoarthros i hasens glidleder (spatt) sags hos 37 % av djuren. Förändringarna debuterade före 2 års alder och förvärrades med stigande alder. Vid makroskopisk och histologisk undersökning sågs osteoarthros även i radiologiskt normala hasar. Undersökningen visar att frekvensen spatt hos uppbundna mjölkkor är högre an vad som kliniskt kan upptäckas. Endast äldre kor med ankylos i hasens glidleder uppvisade de stela bakbensroreiser som anses typiska för spatt.

Kor tillhörande svensk låglandboskap (SLB) hade en lägre frekvens av spatt (20 %) an andra raser. Inom svensk jerseyboskap (SJB) berodde den höga frekvensen av spatt (50 %) på att hela 71 % av de SJB-kor som utfodrats med en högre intensitet under ungdjursperioden hade spatt. Bland SJB-kor med normal utfodringsintensitet var frekvensen av spatt 25 %. Ett sådant samband melian hög utfodringsintensitet och frekvensen av spatt sågs ej inom andra raser.

Undersökta kor i en besättning med lösdrift hade en lägre frekvens av spatt än korna i den uppbundna besättningen. Avkommor till djur med spatt uppvisade en högre frekvens av spatt än avkommor till djur utan spatt.