The Agriland Spring Calf Series is in association with Teagasc DairyBeef 500.
By Fergal Maguire, DairyBeef 500 advisor
In the last three weeks there has being a steady trickle of calves coming onto Dairybeef 500 farms.
From now until the calf is weaned off milk, is the most crucial period for the calf-to-beef enterprise.
The growth rate achieved during these next few months will affect the lifetime performance of the animal.
Optimising the calf’s nutrition and health during this time helps to ensure that the calf has the greatest chance of achieving its full genetic potential for growth and feed conversion efficiency.
Calf illness
Scour, pneumonia, clostridia and coccidiosis are all health issues that are associated with the calf rearing stage, and if a calf becomes ill with any one of these health issues, it will have an impact on animal performance over the lifetime of an animal.
The first three weeks in a calf’s life is usually the danger period for when a calf picks up one of the diseases that can cause scour.
Once scouring, a calf becomes rapidly dehydrated and acidotic. Treatment of a scouring calf should involve rehydration, correction of acidosis, and replacement of electrolytes.
Calf scours is one of the most stressful and expensive diseases that farmers need to deal with. The costs in time, labour, veterinary treatment and loss of calves can be considerable, but there is also the loss in animal performance over their lifetime.
Cause of calf scour Age clinical signs most commonly appear Cryptosporidium parvum First week of life Rotavirus 1-3 weeks-of-age Coronavirus 1-3 weeks-of-age E.coli First week of life Salmonella 2-6 weeks-of-age Coccidia 3-6 weeks-of-age
A variety of infectious organisms can cause calf scours, including rotavirus, coronavirus, E. coli, cryptosporidia, coccidia and salmonella species. However most of these organisms will generally occur in the first three weeks of the calf’s life.
By dairy calf-to-beef farmers sourcing calves that are a minimum of three weeks-of-age, this will greatly reduce the chance of scour outbreaks occurring on farm.
These three-week-old calves should then be only sourced from dairy farmers that are following the Animal Health Ireland (AHI) 3-2-1 colostrum rule and rearing all their calves in hygienic conditions.
At this age, these health calves will have come through the danger period with scour and even if they do get a scour, they will be more than likely able to overcome it without any adverse effects compared to the calves at two-weeks-of-age that may not have received adequate colostrum.
Arrival of calves on farm
On arrival, all calves should be checked to see if they are dehydrated by using the skin pinch method.
If the skin on the calf is slow to snap back in place, feed the calf with 2L of electrolytes and water. Electrolytes should not be mixed in milk. Calf pens should be well bedded with straw and not overcrowded.
A general rule of thumb is to use one round bale of good straw per eight calves a week. At this stage of the calf’s life, avoiding stress is key to maintain a healthy calf.
If buying calves from multiple sources, or if there is history of coccidiosis on your farm, this is now the time to give a preventive treatment for coccidiosis.
At between 3-6 weeks of age calves are particularly vulnerable to coccidiosis. Infection can result in watery faeces which can slow growth rates and lead to failure of calves to wean at their optimal age and weight.
Left untreated, coccidiosis can progress to blood-stained diarrhoea (scours) and even death. On certain farms a second coccidiosis treatment will need be given when calves are at grass as there is an inside strain of coccidia and an outside strain of coccidia.
Pneumonia is the most common disease associated with housed calves. Mortality rates due to pneumonia are approximately 3% in calves in the first 12 weeks of life.
The cost of treatment, loss in performance and time cost due to pneumonia can heavily reduce farm efficiency and profits.
Cattle affected by pneumonia earlier in life take two months longer to finish and even cattle exposed to pneumonia, but not visibly affected, may take one month longer to finish.
Many of the infectious agents commonly involved in calf pneumonia are actually present in healthy calves and in other livestock on farms without causing pneumonia outbreaks.
However, these agents can cause pneumonia if the calf’s immune system is compromised. Factors such as nutrition, colostrum intake, housing, hygiene, ventilation, overcrowding and stress all contribute.
Currently available vaccines protect against lungworm, infectious bovine rhinotracheitis (IBR), respiratory syncytial virus (RSV), parainfluenza- 3 (PI3), mannheimia haemolytica and histophilus somni.
While vaccines do reduce the level of mortality and production levels associated with pneumonia in calves, it will not eliminate pneumonia if management factors such as nutrition, colostrum intake, housing hygiene, ventilation and stress are not correct.
Cattle between three and 12 months of age are at the highest risk of a clostridial disease but can occur at a younger age.
Clostridia are bacteria that live freely in the soil and can cause diseases such as blackleg, tetanus and many less prevalent clostridia disease.
Prevention is better than cure as mortality rates are extremely high if an animal succumbs to a clostridia disease.
Clostridial vaccines consist of a combination vaccine covering a range of clostridial diseases with a primary course of two injections given 4-6 weeks apart. An annual booster injection is then needed to ensure continued immunity.
