The influence of housing and age on the resting, growth and diarrhoea incidence rate was studied by housing male dairy calves for 7 weeks individually (INDIV) or 12 weeks in groups of four; indoors (INGROUP) or outdoors either with (OUTWARM) or without a heated shelter (OUTCOLD). The preweaning (1-7 wk) diarrhoea incidence rates were lower for INGROUP than for INDIV or OUTCOLD. The postweaning growth (8-12 wk) was higher for INGROUP than for OUTCOLD or OUTWARM. The OUTWARM and OUTCOLD calves rested less on their side than the INGROUP calves and more with the neck relaxed. Individual pens did not decrease REM-type sleep, but this decreased overall as the calves aged. In conclusion, the young dairy calves reduced their body area when they were exposed to low temperatures. No clear advantage was found in offering a heated shelter, but a cold environment could be a potential health hazard for calves.
- 413 Veterinärvetenskap