The James Hutton Institute
This page is no longer updated. The Macaulay Land Use Research Institute joined forces with SCRI joined forces on 1 April 2011 to create The James Hutton Institute.
The James Hutton InstituteThis page is no longer updated. The Macaulay Land Use Research Institute joined forces with SCRI joined forces on 1 April 2011 to create The James Hutton Institute.
This page has been mothballed.
A genetic database for performance parameter recording in Danish Angora goats
(Annette Holmenlund, Marie E. Kielsgaard and Jørn Pedersen, Denmark)
Summary
The Danish Goat Registration System is a database storing data on pedigree, reproduction, growth rates, mohair yields, mohair quality and health. The database is based on an unambiguous identification system for individuals and on the farmers' own recordings of breeding and production data. The data stored in the database is used as documentation for pedigree, to estimate indexes and to produce management information for the farmers. The Goat Registration System has been developed since 1992 and today 227 Angora herds are in the system, including 25 Swedish and 7 Norwegians herds. The Nordic Angora goat population consists of many small herds (a total of 4,277 Angoras). This is one of the reasons why we have developed a genetic indexation system over the past 2 years, enabling us to compare animals from different herds and to find the best bucks and does in the Nordic countries. This will ensure the best possible basis for breeding progress and thus a profitable mohair production. How then can we incorporate more figures about mohair quality into the goat registration system? This is one of the main questions to be dealt with in the next two years. We have defined two pre-conditions. Firstly, we would rather accept many quality figures and thus a higher degree of unreliability on the figures than vice versa and secondly, the method should be cheap, simple and user-friendly in order to get full breeder support.
Since 1991, the Danish Angora goat breeders have reported their pedigree, breeding and production data to the computer-based goat registration program which also stores all pedigree data on live animals and embryos imported since 1987.
The purpose of the goat registration program is to develop profitable mohair production, both through breeding and production through the development of breeding values and management information for the farmers.
Two hundreds and twenty seven Angora herds, together with 25 Swedish and Norwegian herds, are using the goat registration programme. The Danish, Swedish and Norwegian Angora goat population total 4,277 live Angora goats (2,777 does) and is thus characterised by many small herds. Eighty-six per cent has among 0-9 kiddings per herd (1995). The Angora goat population consists mainly of Angoras of the Australasian type imported from New Zealand and they are at present being upgraded using Angoras of the Texas and South African types imported in 1992 and 1993 from Australian and New Zealand, respectively.
The goat registration programme is being currently developed and the latest initiatives are the development of linear classification, breeding values (Pedersen, 1994) and "Herd Prints".
The goat registration system is based on an unambiguous nine-digit eartag number which follows the animal from birth to death. It also includes the goat owners' own records of matings (inclusive of the buck's ID), kiddings (kidding ease, mortality, birth weight and ID of the kid), the kid's weights at 2 and 4 months, all fleece weights, disease records, purchase, sale and deaths. Furthermore classification results and mohair test results are recorded.
All recordings are always linked to the unambiguous eartag number of the animal and to the date of the event, e.g. date of kidding and date of shearing.
From the goat registration system, the herd owner gets:
Mohair production consists of two parameters, yield (quantity) and quality. The Angora herds report the fleece weights of every shearing which takes place twice a year - the first one at the age of 5-7 months. A total of 3,136 fleece weights was reported in the period from 1 September 1994 to 31 August 1995.
The quality of the mohair is measured objectively through a mohair test and subjectively through a classification scheme. The mohair test is analysed at the National Research Centre, Foulum and includes fibre diameter, deviation of the fibre diameter, percentage kemp and medullation and per cent roundness. A total of 375 mohair samples has been analysed since it started.
The linear classification results are divided into a figure for body and legs and a figure evaluating the mohair quality: fibre fineness, kemp and medullation, lustre, lanolin, style, character and cover. One hundred and fifty seven animals were recorded in 21 herds in 1995 when linear classification was introduced.
As both mohair yield and fibre fineness are two important economic production parameters, it is important that as many data as possible are collected on these two parameters. It would be a major progress if more data on mohair quality was available in the database.
At the beginning of 1996, our knowledge on Angoras will be further extended as data on three different types of Angoras and their crossbreeds will be analysed.
The traits are divided into 5 main categories:
Female traits:
The animal's own traits
Conformation of body etc.
Mohair production
Mohair quality
Kemp and medullation
Mohair evaluation
Besides the 5 main indexes and the 3 sub-indexes describing the mohair quality, a total breeding index is estimated, the S-index, combining all the indexes. Like sheep and beef cattle breeding, Angora goat breeding is characterised by a very limited number of artificial inseminations. Therefore the breeding animals have only a small number of progeny, often born in one herd. Normally, this has the effect that it is very difficult to estimate breeding values which can be compared -from one herd to another and for animals born in different years. In connection with sale or exchange of breeding stock -and perhaps insemination - some relationships will however be established with other herds. It is thus possible to estimate fairly reliable breeding values.
The estimated breeding values make allowance for the heritabilities of the traits and the known relationships and at the same time a correction is made for systematic environmental impacts. These corrections have the effect that results collected in different environmental conditions (e.g. herds) and for different categories of animals (e.g. sex and age) can be compared.
In order to combine these traits into indices, each individual trait is weighted. This weighting is as far as possible based on studies of the economic value of the traits.
Table 1 shows the average indices of all Angora goats born during the past 6 years. When comparing the results of the different years, we can estimate the breeding progress being achieved. According to Table 1, Angora breeding activities have been based on the evaluation of the mohair. Progress has also been achieved in the field of production and fineness because there is a positive correlation between the evaluation of mohair and the mohair quality. The purpose of estimating the S-index is to increase the total breeding progress in the years to come. It should be possible to heavily improve production figures and fineness, while at the same time, maintaining or moderately improving mothering traits and liveability.
Table 1. Average of indices for birth year and breeding progress per year (1990-1995)
| 1990 | 1992 | 1994 | 1996 | 1997 | Average change per year | |
| number of animals | 651 | 1824 | 1584 | 1408 | 1387 | - |
| S-index | 98.7 | 99.5 | 104.9 | 108.9 | 111.5 | 2.1 |
| Female traits | 100.6 | 101.6 | 99.1 | 98.7 | 98.9 | -0.2 |
| Liveability | 98.5 | 99.6 | 101.4 | 103.0 | 102.6 | 0.4 |
| Body | 100.0 | 99.3 | 101.0 | 101.8 | 101.2 | 0.3 |
| Mohair production | 99.6 | 100.5 | 102.4 | 104.5 | 107.0 | 1.2 |
| Mohair quality: fineness kemp & medullation evaluation |
98.8 99.5 99.8 98.3 |
100.7 99.3 99.7 99.9 |
102.4 100.0 101.9 104.5 |
103.9 99.8 103.6 107.5 |
104.6 99.6 104.0 109.1 |
0.8 0.0 0.8 1.6 |
| Reliability | 12.4 | 12.8 | 9.9 | 8.3 | 7.4 | - |
The goat registration system has been developed since 1991 and the most important task in the two coming years will be How do we incorporate more mohair quality figures into the system?
Pre-conditions
It would be better to have many quality figures and accept a higher degree of unreliability than vice versa. The method must be cheap, simple and user friendly in order to get full breeder support.
Some of the questions we have to deal with are:
Concerning the dissemination of information, we will produce advisory leaflets, slides, videos about the registration scheme, papers on the registration, breeding values, mohair sampling, shearing, treatment of fleeces after shearing, etc.
7-References
Pedersen, J. (1994). Genetic evaluation of Danish Angora goats. In : J.P. Laker & S.C. Bishop (editors). Genetic improvement of Fine Fibre Producing Animals. European Fine Fibre Network No.1.pp89.
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