In order to produce milk, cows must give birth to a calf each year. In the year ending 30 June 2016, 4.4 million dairy calves were born . Dairy calves are either slaughtered as ‘bobby calves’, raised for beef, or raised as dairy herd replacements.
Early separation of bobby calves can create substantial distress for both mother and calf. Their treatment during transport and slaughter is also a serious concern. Disturbing abuse of calves has recently been documented within New Zealand.
- MacPherson L. (2017). Agricultural Production Statistics: June 2016 (final). Table 4. https://www.stats.govt.nz/information-releases/agricultural-production-statistics-june-2016-final, accessed 27 Nov. 2017.
Cows, like humans, are pregnant for nine months, and they too bond strongly with their babies. Hudson and Mullord  estimated that a strong maternal bond is formed after only five minutes of contact, following calf birth. Calves would naturally suckle five to eight times a day for the first few weeks, and stay with their mothers for up to two years. However, dairy calves are generally taken from cows within 12 hours of birth, and cows may show signs of extreme distress when their calves are taken . This can be seen in New Zealand video footage from 2015 and 2016.
Numerous studies have shown that early weaning causes a stress response in cows. Behaviour can be markedly altered, with some cows searching for their lost calves for days. Many farmers will be familiar with their prolonged bellowing, following calf removal. Calves also vocalise for prolonged periods and may alter their behaviour during this time . Use of a judgement bias test (a type of psychological test) has demonstrated mood depression in calves following maternal separation, similar to that seen in calves suffering from pain following hot-iron dehorning .
This is in marked contrast to beef calves, most of whom are reared with their mothers and weaned at around six months of age .
- Hudson SJ & Mullord MM. (1977). Investigations of maternal bonding in dairy cattle. Applied Animal Ethology, 3(3), 271-276.
- Stafford KJ. (2013). Animal Welfare in New Zealand. Cambridge, New Zealand: New Zealand Society of Animal Production.
- Rushen J, Wright R, Johnsen JF, et al. (2016). Reduced locomotor play behaviour of dairy calves following separation from the mother reflects their response to reduced energy intake. Applied Animal Behaviour Science, 177, 6-11.
- Daros RR, Costa JH, von Keyserlingk MA, et al. (2014). Separation from the dam causes negative judgement bias in dairy calves. PLoS One, 9(5), e98429.
Bobby calf slaughter
In the year ending September 2017, 1.7 million beef and dairy calves were slaughtered. Beef cattle are normally slaughtered after being grown to marketable weight as adults, so almost all slaughtered would have been dairy calves . These ‘bobby calves’ are normally slaughtered at around four days of age – the minimum permissible under the Animal Welfare (Calves) Regulations 2016 .
Although these bobby calves must be healthy and fed on the morning of transport, Donovan  found that 3-4% died daily on trucks, in yards, or were condemned as unfit for human consumption due to disease or weakness.
- Ministry for Primary Industries (MPI) (2017). Livestock slaughter statistics. https://www.mpi.govt.nz/news-and-resources/open-data-and-forecasting/agriculture/, accessed 23 Nov. 2017.
- NZ Govt. (2017). Animal Welfare (Calves) Regulations 2016. http://www.legislation.govt.nz/regulation/public/2016/0170/latest/DLM6905457.html?search=ts_act%40bill%40regulation%40deemedreg_calf_resel_25_a&p=1, accessed 22 Nov. 2017.
- Donovan R. (2008). Meeting obligations for bobby calf welfare. Vetscript Apr. 2008, 8-9.