Prevalence of bloat in cows grazing plantain dominant diverse pastures at dry off: A case study

Abstract

The purpose of this study was to document the conditions under which bloat was observed in dry cows grazing plantain dominant diverse pastures in autumn. Symptoms were observed in the autumn period when cows grazed diverse pastures containing plantain (46%), clover (18%), and Italian ryegrass (32%). To further characterise the conditions under which bloat occurred an observational study was conducted in May 2019. A group of 28 non lactating Holstein Friesian x Jersey cows were monitored for appearance of bloat and feeding behaviour following a new allocation of diverse pasture. Bloat symptoms were assessed hourly and feeding behaviour (eating, ruminating and activity) was recorded using CowManager SensOor eartags. Although there was active management to avoid bloat such as feeding silage before a new pasture allocation and using bloat oil in troughs, on the first day of the study 18 cows showed medium to critical bloat signs within the first 2 to 4 hours. Cows that experienced bloat, spent less time ruminating but longer time grazing. Our results do not confirm whether plantain contributed to bloat but we speculate that plantain is likely to delay the onset of bloat. Feeding diverse pastures containing low fibre and high moisture species may require adjustments to management of bloat risk.