Avoiding poor winter thrive - the factors to consider

Farmers often comment in the spring, when animals are returned to grass, that they are disappointed with how their animals have performed over the winter period, with average daily gains of as low as 0-0.3kg/day a common theme.

In this article, Gordon Peppard, DairyBeef 500 Advisor, explains that in order to maximise performance over the animal’s lifetime, it is essential that weanlings achieve a minimum growth rate of 0.6kg/day over the winter housing period.

If stock are only growing at 0.25kg/day or less, they can become stunted and this will have serious consequences on the lifetime gain and finishing performance of these animals. So how can you ensure that your animals meet this target? There are a number of key factors to understand and these are highlighted below.  

Growth potential

Growth potential is a combination of the gender and breed type of the animal. Bulls will have a higher growth potential than steers and steers higher than heifers. Continental animals will have a higher growth rate than dairy-bred stock. 

Duration of finishing period

It is important to have a defined finishing period. When animals reach the end of this period, marketing should occur, as the laying down of fat is more energy demanding than lean tissue deposition, hence slowing the rate of gain in the late finishing period. Heifers generally require a shorter finishing period than steers who in turn return require less than bulls.

Low dry matter intake

Low dry matter intake is one of the primary causes of poor thrive in beef cattle. Dry matter intake is largely influenced by the dry matter (DM), dry matter digestibility (DMD) and preservation of the silage.

Putting an estimate on dry matter intake can be done by weighing blocks of silage / silage bales and having a silage analysis to determine the dry matter of the silage. Very quickly you can calculate how much dry matter your animal is consuming per day. 

Weanlings should achieve dry matter intakes of at least 2% of body weight on grass silage based diets. For example, a 300kg weanling will require 6kg of dry matter per day. Higher intakes can be expected on concentrates or where high DM forages such as maize and whole crop are used. 

Inadequate supplementation

Meal feeding rates are determined by silage quality. Routinely farmers feed the same level of concentrates year in year out with no knowledge of silage quality. Having your silage tested is essential. Without a silage analysis, you are completely in the dark as to what level of performance is possible, and the amount and level of protein that is required in the concentrates you are feeding.

Table 1 presents the supplementation rates required for weanlings and finishing steers/heifers offered grass silage. It is recommended to frontload meal feeding in the first half of the winter, reducing meals towards the turnout date.

Table 1: Meal feeding rates based on silage quality

Parasites

Parasites can have a detrementimental effect on performance over the winter period, if they are not correctly controlled. The main stomach worm of concern over the winter is Type 2 Ostertagia. The Levamizole-based products (yellow drenches) are not effective against this type of stomach worm. Ensure that the stomach worm treatment used will also kill lungworms. 

Dosing for fluke should be carried out after housing, allowing the required period of time for the fluke to develop to a stage where the flukecide will be effective against it. It’s a good idea to rotate flukicide product from year to year. 

The main external parasites are biting and sucking lice, and in some cases ticks. The key to controlling external parasites is to treat all animals in the house at the same time, otherwise the lice will spread from the untreated animals back onto the treated animals.

Environment

One of the biggest factors affecting animal performance is space allowance. Space allowances are presented below in Table 2. Remember that as the stock grow, they will need more space if this hasn’t been taken into account at housing. 

Poorly-designed barriers can restrict intake. Rub marks on the neck of stock can be evidence of a low barrier or stock having to stretch for fodder. Adequate ventilation, air movement and freedom from draughts are also important.

Table 2: Space allowances and feed space requirements for beef cattle

Water supply

Reduced water intake will depress feed intake and consequently performance. Beef animals require approx. 6L of water per kg DM intake. For example, a 300kg weanling eating 2% of body weight will require 6kg of dry matter per day, therefore 36L of water. This will fluctuate depending on dietary specification, environmental temperature and rate of gain. It is recommended that water troughs be inspected regularly and cleaned at least three times a week, or sooner if water is fouled. Water intake will be higher on high concentrate feeding systems. 

Mineral deficiency

Weanlings and finishing cattle need routine supplements in winter. However, while mineral deficiencies are often cited as the main cause of ill-thrift, deficiency is well down the list of blame in most cases where a good mineral supplement is fed. It is important to check that minerals are included at the correct rate for high concentrate feeding systems to avoid toxicity problems

Nutritional diseases

Nutritional diseases like acidosis, diarrhoea, lameness and liver abscesses - many of which are inter-linked - need to be controlled.

Acidosis can occur in beef cattle that are on a high concentrate diets. Causes can include lack of fibre in the diet, rapid introduction of starchy and sugar-based feedstuffs, sudden changes in concentrate type and irregular feeding. Affected animals show signs of kicking at the belly, grinding of teeth, go off their feed and develop signs of colic. Associated problems include diarrhoea and laminitis.   

Access to a good fibre source, straw or haylage, is critical to reduce the risk of this costly condition. Reduce starch/sugar content of the diet. Supplements such as buffers and yeasts may have a role to play, but are no substitute for accurate diet formulation and good feeding management. 

Acidosis can often be sub-clinical and not manifest itself in the ways mentioned above, but still cause sub-optimal performance. Monitoring of finished animals at the factory from time to time may be useful to detect a sub-clinical acidosis problem with no outward clinical signs, such as liver abscesses and other rumen disorders. 

Respiratory problems

Viral pneumonia is the biggest cause of ill-health and death in Irish weanlings every year. Prevention is definitely better than cure. Proper management of weanlings to avoid stress is important, but vaccination is also worth considering. 

Monitoring performance

The winter period on farms in Ireland can last between 90 and 165 days, depending on weather and the part of the country you are located in. This can represent between 25 and 45% of the yearly production cycle on your farm.

Therefore, achieving good average daily gains during this period is essential in order to keep your farm's output high and reduce the days to slaughter.

Poor performance over the winter means extending the animal’s lifetime on the farm, increasing feed required, reducing stocking rate and ultimately reducing performance and profitability on your farm.

The best way to monitor performance on farm is by regular weighing of your animals. Scales can be purchased and retained on farm for years of use, or alternatively ICBF has a number of weight recorders around the country that will weigh your cattle and leave you with a weight report on each individual animal.

At a minimum, animals should be weighed one to two weeks after housing, two to three months later and again at turnout - if going back to grass. This will give a good indication as to how your animals are performing. Regular weighing during the summer months is also very important.

Gordon Peppard works as an advisor on the Teagasc DairyBeef 500 Programme. For more information on this programme, click here.