Friday, 12 August 2016 09:26

Setting benchmarks can reduce calf sickness and death

Written by  Dr Gemma Chuck, Apium Animal Health

VETERINARIAN DR GEMMA Chuck says setting benchmarks for improved calf health during rearing will reduce morbidty and death rates.

Calf hood morbidity (“sickness”) appears to have lasting effects on growth, age at first calving, milk production and longevity.

Research has shown that calves have the highest risk of scours in the first and second weeks of life and this risk declines to a low level by four to six weeks of age.

The risk of respiratory disease does not decline as rapidly as that of scours and remains at a reasonably consistent level until 12 weeks of age.

The presence of respiratory disease at two to four months of age negatively affects average daily gain (ADG), body weight and height.

Research suggests that the presence of septicaemia and/or pneumonia during the first six months of life reduced growth by 13-15 days.

This means it took affected calves 13-15 days longer to achieve the same weight as healthy calves.

The effects of calf hood morbidity on age at first calving (AFC) have also been described. One study demonstrated that heifers which were treated for scours in the first three months of life were nearly three times more likely to calve after 30 months than those not treated for scours.

Additionally, the negative effect of calf hood morbidity on lactation performance indicators such as 305-day milk, fat and protein production suggests that health status early in life can affect production up to two years later.

Research from the United States suggests that calf hood morbidity impacts long term herd survival.

Calves treated for pneumonia in the first three months of life were two and a half times more likely to die between three months and two and a half years, when compared to calves that had not been treated for pneumonia. A similar effect was seen for calves treated for scours less than three months of age, in that they were two and a half times more likely to be sold compared to those not treated for scours.

Thus, the long term effects of calf hood morbidity are multi-dimensional.

Every effort should be made to reduce morbidity rates by provision of pro-active, holistic veterinary advice.

Key performance targets and benchmarks play a role in setting defined goals in an outbreak situation along with routine monitoring of dairy calf rearing performance.

Why do we need benchmarks?

Contrary to the resources available in the dairy reproduction and milk quality fields, performance benchmarks for dairy calf rearing have not been established in Australia.

The Fertility Focus Report (InCalf) and Mastitis Focus Report (Countdown Downunder) have enabled advisors and farmers to identify key areas within their system, allowing strategic advice for improvement.

Key performance indicators such a six-week in calf rate, not-in calf rate, total clinical case rate and new infection rate allow proactive decisions to be made and clear goals to be defined.

In some cases there is a general acceptance of high morbidity (sickness) in dairy calves, with such farms relying heavily on mass antibiotic usage.

However, high levels of mortality (death) are less well tolerated and it is usually at this point that veterinary intervention is sought.

An outbreak situation is likely to be fairly dramatic, requiring strong, yet not always sustainable recommendations in an attempt to reduce the inevitable high morbidity and mortality rates.

This raises the question: “If the farmer had been aware that they were achieving a suboptimal level of care in their calf rearing, could earlier veterinary intervention prevented the outbreak?”

This proactive approach is synonymous with that of Countdown Downunder and InCalf, yet it seems to have been omitted from the dairy calf rearing field.

Development of performance targets

Data from Australian research has allowed development of preliminary benchmarks for passive transfer of immunity from colostrum, morbidity rate and mortality rate. 

Based on this research, the performance targets within a given calf rearing period are:
• Failure of passive transfer: Less than 20% of calves in a group (minimum of 12) with serum protein <5.0g/dL
• Pre-weaning morbidity rate: Less than 10% of calves should be treated with antibiotics and/or electrolytes
• Pre-weaning mortality rate: Less than 3% of calves should die during this period, regardless of the cause of death.

Your vet can discuss with you the requirements for passive transfer testing.

Passive transfer of immunity allows an early indicator of whether calves are receiving sufficient colostrum to combat disease.

Calculation of morbidity and mortality rates rely on accurate records of any sick or treated calves and any deaths that occur during the calf rearing period.

The main thing to remember when referring to these benchmarks is that they are achievable.

Scope for the future

Australian dairy calf rearing systems are very different to those in the United States.

These preliminary performance targets have been developed from data collected on commercial dairy farms in south west Victoria, Australia.

They require further validation in the broader industry in order to become absolute.

However, in the author’s opinion they are a useful objective guide for farmers and veterinarians, providing early indication for improvement.

More like this

How clean is your calf shed?

A critical way to reduce the spread of disease from one season to the next is by removal of soiled bedding and thorough cleaning of the calf shed. Ideally this should be done as soon as possible after the last calf leaves the shed.

Electrolytes: What's in the tub?

Oral rehydration solutions, commonly known as electrolytes, are considered the mainstay of treatment for calf diarrhoea or any dehydration due to disease.

More from this category

Flighty cows produce  less milk

Flighty cows are likely to respond to stress, e.g. change of environment, by producing less milk. This and other intriguing points have been noted during a study of dairy cow temperament at AgResearch.

Double reward for reducing mastitis

INNOVATIONS WHICH led to a 41% mastitis reduction in their herd have earned Tasmanian dairy farmers Phil and Lis Beattie a national award and an international trip.

Cheaper than a lame cow

 

COWSLIPS ARE lifesavers for many cows. Without them many more cows would go to the works. This assumes the slips are put on correctly; I see many instances where they weren’t.

Hygiene underpins calf rearing program

After moving home to the family farm, following time spent living and working in the Caribbean, Annabel Mangal began rearing and selling calves to local hobby farmers in the Adelaide Hills.

Think nutrition now for better production

Farmers should be thinking now about dairy nutrition to set their herds up for better milk production and fertility during the next lactation, says InCalf’s Dr Barry Zimmermann.

 

Dehorning is a routine animal husbandry practice carried out to lessen the risk of injury to stock, people and other animals during handling and transport of stock.

IN MY role as President of the Australian Cattle Veterinarians, I hear about issues that are concerning cattle vets from all over Australia.

SINCE SOUTHERN Riverina dairy farmers Rob and Gai Singleton moved to the area in 1994 they have developed a strong appreciation for the value of cow comfort in their dairying operation.

Leave a comment

Make sure you enter the (*) required information where indicated.\nBasic HTML code is allowed.

» Get social

When butter and chocolate collide

TWO New Zealand companies Lewis Road Creamery and Whittakers have teamed up to deliver what must be every dairy lover’s dream: chocolate butter.

» E-Newsletter

Subscribe to our mailing list

* indicates required