BOTSWANA: performance testing of beef cattle

BY J.C.M. Trail and T.W. Rennie

This article describes the details of a performance testing programme for beef cattle in a developing country. Full information on the system that is now in operation in Botswana, including the computer flow charts involved, are available in a report entitled “A computerized system for rapid handling, analysis and use of beef cattle performance records,” which may be obtained from the Animal Production Research Unit, Ministry of Agriculture, Private Bag 33, Gaborone, Botswana

1. Performance records are used for the selection of beef cattle replacement stock in Botswana

The use of performance testing as an aid to genetic improvement of beef cattle is well known. While in recent years there has been increasingly wider recognition and acceptance of the virtues of performance testing of beef cattle in developing countries, there has been little demonstration of how, in practice, programmes can be implemented.

The major problems for successful operation of long-term performance testing are concerned with the ease and rapidity of accurate collection, handling, analysis and use of records covering the period from birth to final disposal of the animals.

This article is concerned with these aspects of performance testing and illustrates a system in operation in Botswana for the collection and handling of beef cattle performance records. At present the lifetime records of over 5 000 cattle on 16 government ranches and the part-life records of over 10 000 cattle on recorded farms and artificial insemination stations are involved. The major traits recorded are reproductive performance, growth, viability and mothering ability (Animal Production Research Unit, 1974).

J.C.M. Trail is Coordinator, Range and Animal Production Research, and T.W. Rennie is Animal Production Officer, Ministry of Agriculture, Gaborone, Botswana.

2. Sample pages from the monthly weight record book, the treatment book and the birth notification book

Under the extensive range conditions of Botswana a recording system for individual herds must permit the accurate collection of required information in the simplest possible way. In general, information is required for decision-making at both herd and national level. At herd level it is needed for the evaluation of young bulls with a view to sire replacement and sale of breeding stock; of young heifers with a view to their selection as herd replacements; and of cows in order to decide whether to retain or to cull them. At national level information is needed in order to select outstanding sires for use and further testing for artificial insemination. Data from all sources are needed to allow valid comparisons of breed types, to determine the effects of crossbreeding and to study any differences in performance of the types in different areas of the country.

Data collection

All ranch or herd recording is carried out in three duplicate books: a birth notification book, a treatment book and a monthly weight record book. A page from each book is illustrated in Figure 2. Pages are serially numbered in advance so that any misplaced records can be easily checked.

The calving season lasts for three months each year. Within 24 hours of each calving, the cow and calf are weighed; the calf is ear-tagged; and the calf number, date of birth, sex, weight, dam number, dam breed, sire number, sire breed, dam weight and any relevant comments are entered on a duplicate sheet in the birth notification book. During the calving season the top copies of birth sheets are dispatched daily to the central animal production research unit.

In this way, information on calf births can be rapidly checked and any obvious discrepancies or omissions corrected within a reasonable period of time.

Monthly weighings are carried out, all animals being starved overnight. At the beginning and end of each weighing session a nuxbered test weight is weighed and recorded to test the scales. At weighing, the animal number and the weight are entered directly into the duplicate book (Figure 3). Immediately after each weighing session the top copies of the weight sheets are sent to the central animal production research unit.

All information other than births and weights is recorded in the treatment record book. “Treatment” covers sickness, vaccination, dehorning, castration, grazing records, increase or decrease in stock other than by births, breeding reports and so on. Treatment sheets are sent at frequent intervals to the animal production research unit.

Data handling and analysis

Birth records

Birth records are checked on receipt and all details, plus details of ranch, breed, month of birth, sex, age of dam and previous parous state of dam, are entered on an appropriately laid out coding sheet. This operation is shown in the illustration below (Figure 6).

3. The animal's number and weight are entered directly into the weight record book

4. Ear-tagging at birth to ensure accurate identification	5. Branding at weaning

Cards are punched and verified and, when the last calf of the season has been born, this pack is fed into the beef cattle performance recording system stored on an I.C.L. 1902 com puter.

6 Preparation of coding sheet

This system automatically sorts out and produces a new file for this calf crop, calculates by least squares the birth weights adjusted for environmental effects specified, and updates the main cow records with this new calf crop information. At the same time, a print-out is produced of the new calf crop and an updated printout of the cow records. The new calf crop print-out is illustrated in Figure 9; the information produced at this stage goes as far as the corrected birth weight only. The updated cow record is illustrated in Figure 10.

Weaning weight records

Animals are weaned at 7 months of age ±2 weeks. Adjusted 210-day weaning weights are calculated on a microcomputer from the monthly weighings, and entered on appropriate coding sheets. Cards are punched, verified and fed into the system, which calculates by least squares the weaning weights adjusted for environmental effects: works out weaning weight ratings within breed types; updates the calf crop record with this information: updates the cow records with the adjusted calf weaning weights and ratings; and produces new cow and calf listings, updated to the weaning stage (see Figure 9 for weaning weight rating and Figure 10 for corrected weaning weights and weaning weight ratings).

18-month weight records

Weights received at approximately 18 months of age are adjusted by interpolation to 545-day weights on the microcomputer and entered on appropriate coding sheets. Cards are punched and verified and fed into the system which calculates by least squares the 18-month weights adjusted for environmental effects; works out 18-month weight ratings within breed types; and produces a calf listing finally updated and printed as illustrated in Figure 9.

7 Weight adjustment on a microcomputer

Treatment records

Deaths and removals are entered on appropriate coding sheets when received, punch cards are produced, and this information is fed into the system each time weight records are entered. The main files are automatically updated and each print-out thus has a section concerned with animals present at that time and also a section covering deaths and removals.

Use of information

Annually, at herd level, the updated listings are used to arrive at decisions on which cows are to continue in the breeding herds and which are to be culled (based on their calving performance and calf weaning weights as laid out in Figure 10); which young heifers are to enter the breeding herds as replacements; which young males are to be retained as bulls and which are to be castrated (these three decisions being based on the 18-month weight ratings shown in Figure 9). A simple code alongside each animal number is then fed into the system and results in the automatic addition or removal of selected animals to (or from) the various groups: breeding animals, other stock older than 2 years, and removals and sales.

Annually, at national level, additional information available from all sources is used to make comparisons of breed type performance. These become increasingly accurate with time. This enables logical decisions to be made and implemented through the breed types offered for sale through the Botswana Government bull distribution and artificial insemination schemes (Animal Production Research Unit, 1974).

8 (below). Transfer of data to punch cards

9 and 10. Calf listing (breed, sex, previous parous state [PPS] are coded; weights and rating areexpressed in pounds), and breeding cow listing.

REFERENCE

Animal Production Research Unit. 1974. Beef Cattle and Range Research Programme in Botswana 1970–73. A.P.R.U., Private Bag 33, Gaborone, Botswana.