A case-contro
l study was conducted on 46 far
ms in south-eastern Austra
lia with a recent history of congenita
l chondrodystrophy of unknown origin (CCUO) between 2002 and 2007. For each far
m data was co
llected using face-to-face interviews concerning the
manage
ment of case and contro
l mobs during the gestation period in which affected ca
lves were born. Data concerning the paddocks in which gestating catt
le were
maintained was a
lso co
llected for ana
lysis. Three separate
mu
ltivariab
le
mode
ls were constructed using genera
lised
linear
mixed
mode
ls (GLMMs). The first
mode
l was based on the dichoto
mous outco
me of
mob status (affected/not affected) and inc
luded exp
lanatory variab
les for
manage
ment and environ
ment factors. The second
mode
l used a nove
l approach, taking into account the nu
mber of cases in affected
mobs in order to uti
lise avai
lab
le data. The outco
me events/tria
ls was used where the nu
merator was equa
l to the nu
mber of affected ca
lves in a
mob, and the deno
minator was equa
l to the tota
l nu
mber of ca
lves in the
mob. The third
mode
l used the dichoto
mous outco
me paddock status and inc
luded environ
menta
l and soi
l variab
les for paddocks invo
lved with case and contro
l mobs. Confounding for da
m age and year affected was inc
luded in the
mob outco
me
mode
ls, and rando
m effects for paddock and far
m were incorporated into the
mode
ls.
The birth of CCUO calves was associated with dams grazing native pastures on hilly terrain during gestation. Low levels of pasture were also associated with the outcome. The two models used for the mob outcome were similar in many respects. The events/trial model included the use of supplemental feed and an interaction term. This study demonstrates an association between a maternal nutritional disturbance and the occurrence of CCUO.