There are nearly 1.7 million dairy cows in Australia. On average, each cow produces close to 5,500 litres of milk a year. In contrast to the intensive nature of dairy production overseas, where cows may be housed in sheds for their entire lives, most Australian dairy cattle spend at least part of the day on pasture. The estimated average herd size is 268 cows, however there is an emerging trend towards large farms of over 1,000 cows which may or may not house cows permanently indoors.
Large-scale dairy farms that house cows indoors in big sheds all year round without access to pasture tend to raise concern amongst the general public and amongst dairy farmers themselves be it around the economic, environmental or social impact of such systems. From a social sustainability perspective, it is the animal welfare risk of large-scale, intensive systems that concerns the RSPCA.
The increasing demand for milk and milk products is almost inevitably followed by increasing intensification of the industry that supplies that product. Indoor housing of large numbers of cows that can be automatically monitored, fed, watered and milked allows cows’ lives to be almost fully controlled with relatively low labour input. These aspects of large-scale indoor housing may be advantageous to the farmer, but what impact is there on the health and welfare of the dairy cow?
Cows that have access to pasture will typically spend between 6 to 12 hours per day grazing. Providing access to pasture gives cows the time and space to ruminate (chew their cud), allows cows to select their feed, increases the overall time spent searching and ingesting food and thus prevents boredom and its associated stereotypies (e.g. tongue rolling). Access to pasture has been shown to result in fewer locomotive disorders, reduced lameness and mastitis and reduced teat injuries compared to indoor-housed cows.
Indoor housing has been studied extensively and a number of characteristics of indoor housing are directly relevant to cow welfare. Dry, deep straw bedding is necessary to promote resting, reduce lameness and injuries and to increase locomotion. Adequate ventilation is necessary to avoid heat stress, and reduce ammonia, sulphur, dust and microbes in the air. There should be no competition for access to water or feed. Sufficient space is needed to ensure there is no competition for lying space, that there is opportunity to exercise (to reduce calving-related disease, mastitis and leg problems), and that cows can escape aggressive encounters. Cubicles should be designed to allow cows to get up and down normally. And, finally, the design should allow for self-grooming and grooming of others as well as other behaviours that cows carry out in synchrony.
In order to meet the behavioural needs of the cow, loose, deep-straw housing with some daily access to pasture appears to be preferable to indoor housing alone to improve general health and overall welfare of the dairy cow.