6 areas to focus on to reduce calf stress

The average dairy calf faces many potential stressors in the preweaning period including birth, transportation, disbudding/castration, weaning and mixing. Most of these stressors are inevitable in calf-rearing production systems but are manageable if the calf timeline is considered.

Stress in a calf’s life can start the day a calf is born.  Difficult calving is proven to cause problems such as reduced passive immunity transfer, Morbidity and respiratory disease as well as reduced daily life weight gains (DLWG).

Choice of sire, size at breeding and nutrition during the dry period can all influence calving ease.

Transporting calves can especially be a stressful time, including being introduced to new groups, change in diet, dehydration and thermal stress.

Adjustments in the transportation environment such as temperature, stocking density, distance and type of road travel can be adjusted to reduce the stress of transportation. It Is important to note that a one-day-old calve is not fully immunocompetent and does not thermoregulate like a calf that is older than one week.

According to guidance regulation set out by (gov.uk, 2003) you shouldn’t move a newborn animal until its navel has completely healed which is typically 7 days.

Inadequate housing can be stressful for calves and cause issues such as temperature being above the upper critical limit (UCT) and below the lower critical limit (LCT), and lack of ventilation can irritate the respiratory tract and mucous membranes.  This can lead to permanent damage to the lungs and encourages micro-organisms.

Read more: Heat Stress in Calves - How To Avoid It?

Having adequate space for calves is critical.  Overstocked sheds result in damp bedding and poor air quality leading to an increased risk of disease in young calves. It is important to consider that Increased space for calves is thought to increase cleanliness and average daily live weight gain.  Studies show that increased space causes a faster clearance of hormones after the release of cortisol (stress hormone) which ultimately means that the calf appears less stressed.

Individual housing can reduce the risk of disease transmission. However long term the calf may have less immunity. Group housing increases the risk of respiratory disease and increases stress response to handling and transportation.   However long-term increases starter intake reduces stress at weaning and increases DLWG. In order to reduce stress when transitioning into a group, you should consider Transitioning calves into small groups before they enter large groups.

Castration should be done effectively and humanely in order to reduce stress.  US studies conclude castration after birth causes less stress compared to castration at or after weaning calves. This is supported by welfare policies which recommend castration at an early age. Studies also support the use of non-steroidal anti-inflammatory drugs (NSAIDS) at the time of surgical castration to reduce stress. One study investigated surgical castration and the use of a rubber ring.

Surgical wounds heal after a 4-week period compared to rubber ring calves taking a minimum of 8 weeks to heal. The rubber ring calves gained less weight, lay down less frequently and had a lower intake of starter feed. The trial concluded that the rubber ring-castrated calves experienced a lot more pain in the weeks after the procedure than the surgical method.

The ideal time to disbud is when animals are young and when the bud is just erupting reduces the likelihood of complications such as infection or bleeding. At two months of age, the horn bud attaches to the skill.

Local anaesthetics and non-steroidal anti-inflammatory drugs (NSAIDS) should always be used to alleviate pain during and after disbudding.

Calves should be weaned based on concentrate intake rather than weight size or age.  Concentrate intake is a good indication of rumen development.  A fully developed rumen will support the nutritional demands of the calf. In order to reduce the stress after weaning it must be gradual over a 3-week period.  Wean calves by reducing the volume of milk per feed and reducing the number of feeds per day.

Stress at weaning has the potential to affect a calf’s immune system for a minimum of two weeks which can make calves susceptible to disease and reduce DLWG. To reduce stress at weaning keep everything consistent such as housing and social group for two weeks after weaning. To reduce stress, make no changes to housing, feed, water or social group for two weeks after weaning.  Also avoid stressful procedures at/ around weaning, such as vaccination disbudding and castration.