The First 12 Weeks at Grass for Dairy-Beef Calves

The First 12 weeks at grass for dairy-beef calves (PDF)

When calves underperform during their first season at pasture, it makes it difficult to achieve key performance targets, irrespective of system further down the line. Failing to hit an average daily gain target of 0.7-0.8 kg/day results in delayed slaughter, the production of lighter carcasses and/or the introduction of additional concentrates to try and recover the loss in performance recorded over the first grazing season. Therefore, ensuring calves perform to their optimum over the first 12 weeks of life is important.

Transitioning to the Outdoors

• The majority of calf-to-beef producers opt to wean their calves prior to moving them from the calf shed to the field.
• During this period, calves may suffer a post-weaning growth check and subsequently disease outbreak as a result of: the low intake of dry feed up until weaning; the high intake of low-energy, bulky forages; or stress when feeds are changed.
• Feeding concentrates before, during and after weaning should limit the level of growth check experienced.
• Calves should be offered concentrates (1-2 kg/day) for 2-3 weeks post-turnout.
• Concentrate supplementation provides the calf with adequate time to become accustomed to grazing before an all-grass diet is offered.
• An animal health protocol is recommended to reduce the possibility of disease onset. RSV, PI3, Mannheimia (Pasteurella) haemolytica and IBR are common causes of respiratory diseases in Ireland.

When and Where to Turnout Calves?

• Only correctly weaned and healthy calves should be turned out to pasture.
• Ensure all calves are consuming concentrates prior to turnout.
• A well-sheltered paddock should be targeted.
• Avoid turning calves out in unfavourable weather conditions – avoid extremes of warm, wet or cold.
• Turnout calves to alternate fields each year to avoid the build-up of pathogens and diseases.
• Ensure calves have a clean, fresh source of water at all times.
• Target a pre-grazing cover of <1,000 kg DM/ha to encourage grazing at turnout

Grassland Management

Excellent grassland management is essential to achieve the desired level of performance from calves over the first 12 weeks following turnout.

• Calves can be selective grazers and providing quality grass must be a priority.
• Don’t force calves to graze out paddocks like older stock.
• Calves should be offered fresh grass every 3-4 days; don’t leave calves in the one paddock for long periods of time.
• When settled or when grass is a large percentage of the diet, the ideal pre-grazing grass covers for calves are 1,000-1,400 kg DM/ha.

Monitoring Performance

• Weighing of calves is critical and should be carried out a minimum of three times a year to determine if cattle are hitting weight gain targets.
• Calves should be weighed at turnout, mid-season and again at housing.
• Dairy-beef calves are typically turned out to grass at approximately 85-100 kg.
• Completing mid-season weighing will provide you with information to see if calves have reached the desired weight gain targets over the first 12 weeks at pasture.

Animal Health

To gain 0.7-0.8 kg/day, calves must remain healthy. When a calf suffers a health set back, its feed intake and daily weight gain will be affected. If calves are coughing or an illness is suspected, seek veterinary advice and identify the cause of the problem through nasal swabs, blood tests or faecal samples. When a vaccination protocol (pneumonia, IBR or clostridial diseases) is being implemented, ensure that the programme is up to date and calves have received their booster shots prior to turnout.

Table 1: Effects, Symptoms and Treatments Options for Gut Worm, Lungworm and Coccidial Infections

Effects	Symptoms	Treatment/Control
Gut Worm
Associated with appetite suppression	Heavily infected calves may experience scouring and a lack of thrive	Know what actives/classes were previously used to help avoid resistance
Sub-clinical disease can result in failure to meet weight targets		Dose only when need; use faecal egg count results or animal performance
Dairy-beef calves are more susceptible to gut worm infestations than suckler calves	Reduction in growth rate could be as high as 50%	Use the recommended rates; don’t under dose animals. Administer the product in the correct way
Sufficient immunity is usually developed after the first grazing season to prevent clinical disease		A Faecal Egg Count Reduction Test or drench test may be required to test the efficacy of some classes
Lungworm / Hoose
Nature and severity of lungworm infection depends on the number of larvae that are ingested and the response of the animal	Hoose should be considered when cattle are seen to be coughing at pasture. A harsh and deep husky cough is heard	A faecal sample can be tested in the laboratory for the presence of lungworm, but the disease is sometimes due to the larval stage of the worm which cannot be detected with this test
Individual animals will differ with regard tothe severity of the symptoms	Moderately affected animals will have bouts of coughing even when resting
Parasitic bronchitis is the main issue in previously naïve cattle	Heavily infected animals will suffer from respiratory disease, have an increased breathing rate and open-mouthed breathing	Most available anthelminthics are effective against larvae and adult lungworms
	The tongue will appear as they try to cough	Cattle should be treated as soon as possible; there may be varying degrees of infection in one group
Coccidosis
Poor thrive and mortality in severely infected animals	Tends to be seen in cattle between three weeks and nine months of age	Where there’s a history of coccidosis on the farm, vigilance is required
	A watery scour due to damage of the intestinal mucosa	Prophylactic dosing of calves is common
Sub-clinically infected animals will as suffer a performance set back	Calves become dehydrated, may start to pass blood, shed part of the intestine lining and become weak and uncoordinated	Taking dung samples from a number of animals within the group is also advised as animals failing to exhibit clinical signs may have a high coccidial oocyte burden
	Calves may suffer from a sub-clinical infection and show very few symptoms
	Calves that have the condition can often be seen straining