05 July 2023

Results from the cow-calf contact systems study

Researchers in Teagasc Moorepark have studied the impact of two different cow-calf contact rearing systems compared to the conventional Irish calf rearing system. The results of this research were presented yesterday, July 4th, at the Teagasc Moorepark Open Day.

Study background

In current dairy calf rearing systems, cows and calves are separated soon after birth. Early separation is done so that cows can be managed with the rest of the milking herd and calves can be artificially reared by the farmer, ensuring proper colostrum intake and reduced risk of disease exposure.

Historically, early separation was thought to be a more welfare-positive experience for the pair as it prevents the formation of the maternal bond between cow and calf; however, this view has come under scrutiny by researchers and consumers alike. Surveys have shown that in Ireland and around the world, consumers have become increasingly concerned about cow-calf separation at birth.

Teagasc Moorepark cow-calf contact study

A study was carried out in Teagasc Moorepark to investigate the impact of two different cow-calf contact rearing systems compared to the conventional Irish calf rearing system on dairy cow and calf production, health, and welfare, as well as the differences in labour between the different systems.

Fifty-four cow-calf pairs (18 pairs/system) were balanced across the three systems: full-time access (FT), part-time access (PT), and no access (control).

The FT pairs had constant access to each other; after three days of bonding indoors cows and calves were turned out to pasture fulltime. The PT pairs had contact by night: calves were kept indoors in a straw-bedded pen, their dams grazed from 8am to 3pm, cows were then housed in a cubicle area adjoining the calves, to allow calf access.

The PT cows were milked once a day (OAD) in the morning (8am). The FT and control cows were milked twice a day (TAD). The control pairs were separated immediately after birth, after which the calf was artificially reared and the cow joined a conventional herd of cows at grass.

All calves were weaned at eight weeks; control calves were gradually weaned by the automatic feeder, while the FT and PT calves were weaned and separated from their dams in a 7-day gradual process, where PT cows switched to TAD milking.

From birth to three weeks post-weaning, calf health and labour were evaluated twice-weekly, and calf weight and behaviour were recorded weekly (behaviour: daily during weaning). Cow production (milk yield, milk solids, and somatic cell count (SCC)) was measured weekly for the duration of their lactation. Cow weight and BCS were evaluated weekly during the first 12 weeks of lactation and at week 35 (end of lactation).

Calf results – health, behaviour, growth and labour

Four FT calves (4/18; 26%) were removed from the system due to illness. The FT and PT calves were more likely to require antibiotic treatment than the controls. Faecal and eye issues were more common in PT calves than both control and FT calves.

Abnormal behaviours (e.g. cross suckling) were seen most often in the PT group, which can indicate challenged welfare. Calf growth was similar for FT and PT calves; control calves weighed less than both groups at 28 (49.0 vs 55.5 kg), 56 (69.0 vs 82.1 kg) and 77 (81.8 vs 90.8 kg) days.

Calving labour was 90% greater for the control system than the FT and PT systems. Weekly labour input was 51% greater for the FT system than control and PT systems. It should also be noted that separating cows and calves daily poses a health and safety risk to farmers. Weaning labour was negligible for control calves (due to automatic feeder), but considerably higher for both FT and PT systems (including cow-calf separation and movement). Consequently, labour was highest for the FT treatment.

Cow results – production and health

During the cow-calf contact period, the FT and PT cows had lower parlour milk yields than the controls, due to calf intake and OAD milking of the PT cows. After weaning and separation, the FT and PT cows’ milk yields increased, but never reached the level of the controls (Figure 1).

Cumulative 35-week milk yield for the FT and PT cows were 24 and 32%, respectively, less than the controls (5,034kg). Cumulative milk solids yield was similarly affected; the controls (449kg) produced the most, followed by the FT cows (332kg) and then the PT cows (291kg). Neither mastitis incidence nor SCC differed between systems throughout the entire 35-week lactation.

After eight weeks of lactation, the PT cows (519kg) were heavier and in better BCS (3.16) than control and FT cows which were similar weight (481kg), but BCS of FT was greater than the controls (3.03 and 2.94, respectively). The PT cows (535kg) remained heavier than the FT (502kg), but not the control cows (523kg), at the end of the lactation, and were in better condition (3.20) to the similar control and FT cows (3.02).

Figure 1. Effect of cow-calf contact systems (control (C; ●); full-time access (FT; ♦), part-time access (PT; ▲)) on average daily parlour milk yield (kg/d) across the first 35-weeks of lactation

Conclusions

Calves reared in the two cow-calf contact systems had contact with their dam, increased growth pre-weaning, and lower calving labour, but poorer health, behaviour, and post-weaning growth.

Daily labour required for the two cow-calf contact systems was higher than the control system. Cows in the cow-calf contact systems had contact with their calves without an increase in SCC or mastitis incidence; however, milk yield and milk solids yield were substantially reduced for FT and PT cows during and after the cow-calf contact period, leading to lower cumulative 35-week lactation yields.

This paper by Sarah McPherson, Alison Sinnott, John Paul Murphy, Katie Sugrue and Emer Kennedy was taken from the Moorepark ’23 Open Day book. This research is funded by Science Foundation Ireland and the Department of Agriculture, Food and Marine on behalf of the Government of Ireland – VistaMilk. For more from the Moorepark ’23 Open Day, click here.