Profit - at calving time

Difficult calvings, dead calves, all of which increase stress and the number of sleepless nights at calving time. But you can now do something about it. Information is now available which allows you to base your bull selection on facts.

During the last 30 years the industry progressed by simple breed substitution, imported continental breeds. Now, the next generation of beef producers must look at what they have inherited and select those animals capable of delivering a profitable future. Fortunately, modern technology and breeding tools are available and if used correctly, can help make the difference. It is important when purchasing any pedigree sire to base the final decision on both visual assessment and genetic information.

These are given for a number of recorded traits. AI Services collect the information from pedigree breeders in Northern Ireland and it is then processed by Signet, through the Beefbreeder service. This is possible due to a powerful computer program, known as Best Linear Unbiased Prediction ‘BLUP’. It is able to separate out the genetic factors influencing an animal’s performance from the environmental factors, ie. feeding level and feed type. It is determined by the animal’s own performance and also the performance of it’s relatives. Therefore, using EBV’s to aid stock selection means you are basing decisions on an animals estimated genetic ability and not only on the stockman’s ability to turnout stock.

The EBV’s associated with calving are shown in Table 1. To maximise financial gain it would be best to select bulls with the relevant correct balance of positive and negative trait values, as highlighted.

	Unit of measurement	A positive figure indicates	A negative figure indicates
Gestation length	Days	A longer gestation	A shorter gestation
Calving ease	Expected change in percentage of unassisted calvings	Easier calving sires	More difficult calving sires
Birthweight	kg	A heavier calf at birth	A lighter calf at birth

Each EBV has an associated accuracy value expressed as a percentage point ranging from 0 to 100. The greater the value the more accurate the EBV.

To simplify selection decisions these values have been combined into a multi-trait selection index, known as the Calving Value Index.

This is an overall assessment of the economic value of an animal’s effect on calving, designed to help producers select easy-calving bulls. It is calculated by combining the gestation length and calving ease EBV’s, which also takes into account the birthweight EBV. The calving value is presented as a cash value per head, representative of the bull’s genetic ability. As a bull passes on half his genes to the next generation the value must be halved. For example a bull with a Calving Value of +4 is expected to produce calves which save an average of £2 each in costs associated with calving, compared with a bull with a Calving Value of 0. Positive values mean increased profits, negative values mean a reduction in profits.

Compare two bulls. Bull A carries superior genetics for both calving value and beef value when compared with bull B.

	Bull A	Bull B
Calving value	+4	-2
Increased return/calf (£)	2	-1
Number of calves sired per annum	50	50
Return/annum (£)	100	-50
Return/bull (£) (assuming a bull produces 5 crops of calves	500	-250

Bull A generates an extra £750 income as compared to bull B and with increased selection by pedigree breeders the financial rewards will increase. At Greenmount College the average calving value of the stock bulls is 1. Bulls with high negative values are avoided to ensure physical and financial losses at calving time are kept to a minimum.

So the simple message is: