- Better kid crops from Angoras
|Last update: April 4, 2012 03:55:29 PM|
BETTER KID CROPS FROM ANGORAS
K. M. van Heerden
During February 1967 a tour was undertaken through the Angora farming areas and more than forty farmers were interviewed. Although grazing conditions were extremely poor, results for the 1966 kidding season were interesting and instructive.
Abortion: Owing to the severe drought kidding was generally very poor. This was also found to be the case with merino flocks.
It was gratifying to note that most farmers have adopted the elimination of aborters as standard practice. One of them, who had already attained as high as 93.5% kidding, stopped culling aborters for two seasons and during 1966 obtained only 64% kids. Another farmer in the neighbourhood under similar grazing conditions reared 93%. Out of 600 ewes only 44 were without kids at weaning. Of them 7 had aborted, while the rest were young ewes. In another area, where kidding on the whole was very poor, one farmer had only two ewes which had not kidded. One died and the other had aborted. He also culls young ewes which do not produce kids.
Dry Ewes: Although the average abortion percentage shows a downward trend, there is nevertheless a tendency towards an increase in the percentage of dry ewes. Data obtained from a farmer who keeps accurate records are instructive. Kidding percentage increased from 80% to 87% during the past three seasons, abortions decreased from 7.2 % to 4.6 %, but the percentage of dry ewes increased from 5.2% to 29%. It appeared that he not only retained his dry ewes every year, but that all his ewes were classed annually. The adult ewes culled in 1966 were all ewes which had reared a kid.
It is of the utmost importance that we should not stop with the regular elimination of aborters, but ewes which do not produce strong, viable kids should also be considered. The tendency towards classing adult breeding ewes annually on mohair and conformation only, cannot be too strongly deprecated.
A positive approach to better kidding results can be made on the following lines:
The number of young ewes added to the flock is usually determined by the number of deaths, old ewes, aborters, etc. It is a well-known fact, however, that the breeding potential of young ewes is not as high as that of adult ewes. After classing the young ewes it may be found that there is an extra number of them, just about as good as those added to the flock. It is recommended, therefore, that instead of 100 for instance, 150 be added. At the end of the season those young ewes which have produced kids are retained and the rest culled. It is also a well-known fact that, in all breeds, a young ewe which has kidded or lambed has a better history of reproduction than one which reproduces only at a greater age. By this means it is no longer necessary to retain in the flock those old ewes which do not produce mohair economically.
Ram factor in a Flock: On most farms the number of rams used varies from 1 % to 2% of the flock, and the great majority of them are old. Seeing that it is possible for more than 90% of the kids to be born during a three-weeks period the minimum number of rams used should be from 2% to 3%.
The general tendency to use a ram till it reaches a ripe old age is risky. The chances for him to mate with his own progeny are increased and can reach dangerous proportions. As far as abortion is concerned the practice is dangerous since the ram may also carry this weakness to his offspring.
It is recommended therefore that rams be purchased from blood lines where abortion is not a problem, and that in any case a ram should not be used for too long a period. Where for any particular reason a ram is to be used for a long time it is necessary to select his ewes specially.
Feeding: This aspect remains one of the basic factors of good breeding results. Steady, normal growth from birth is essential to ensure maximum development of the reproductive system. It will be found accordingly that a higher percentage of young ewes can be mated successfully.
Both rams and ewes should be in good condition before mating. It has been established that sperm cells require about 63 days to develop from the initial stage to maturity. Special feeding should therefore be commenced about 9 weeks before mating to obtain the best results from the ram, and not six weeks as is the usual practice.
To avoid the loss of fertilised egg-cells in the ewe it is of cardinal importance to maintain a sustained high level of feeding during the early stages of pregnancy. In an instance in Australia the percentage loss in a group of Merino ewes, which became pregnant after the first mating, was as follows: 20% up to the 30th day 3% from the 30th day to just before birth 10% during and just after birth.
In ewes which became pregnant only after the second or third mating the percentage loss was 48 %. During the late stages of pregnancy the feeding level should of course again be high to ensure good milk production.
Hitherto attention has been devoted particularly to the second stage where abortion is easily observed. It has now become necessary to pay attention to the first and third stages as well.
Mating: There is a tendency to start mating as early in the season as possible so that kids may be born early, the idea being that these would grow out better. In practice this is seldom the case, since, as a result of better feeding conditions, the ewe which kids later is able to produce more milk and is in a better position to rear her kid. It would appear also that the conception rate during the first oestrus period is considerably lower than in the second or third periods. Farmers who do their mating during these periods generally obtain better results than those whose ewes are mated very early.
We therefore recommend that teasers be used until they become fairly active at which stage they should be replaced by an adequate number of fertile rams. It will be found that the majority of ewes will conceive within three weeks.
By good mating practice, and with reasonably good feeding conditions, one farmer's results for 1966 were as follows: Of 500 ewes mated 50 two-tooth ewes did not become pregnant and no abortions were noticed. The remaining 450 ewes produced 480 kids of which 462 reached weaning age.
Kidding: Management in this case was found to be generally fairly good. The practice of kidding in kraals or paddocks can result in dysentery becoming a real problem. Inoculation of heavily pregnant ewes against this, will help to prevent losses.
I would like to draw attention to what one farmer did to obtain maximum use of his lands during the recent drought. During mating, which lasted four weeks, he used marking tabs with a different colour for each week and then made a paint mark on the horns accordingly. During lambing the ewes could thus be brought to the lands in groups and the fullest use of the available grazing could be made.
On account of the overall low fertility of Angoras at present, the idea has been put forward that artificial methods should be resorted to in order to ensure three kidding seasons in two years. This will be a difficult process, involving all sorts of practical management problems.
In a previous publication I made the statement that the Angora goat is one of the most fertile of domestic farming stock. After this tour I am more convinced than ever that this statement is correct and the ideal of rearing over 100% kids could readily be attained. During the past season some farmers even encountered ewes with triplets. Good feeding, mating and overall management, and elimination of ewes not producing viable kids, are basic essentials. In this connection it would be profitable to study once more the pamphlet entitled "Make Angora Farming More Profitable" where a number of useful practical hints are given.
(a) Adequate feeding of both ram and ewe is a basic requirement as is the case with any breed of farming stock.
(b) A higher percentage of young ewes than is actually necessary should be mated.
(c) Rams should not be allowed to grow old in the flock.
(d) Mating should not begin too early in the season.
(e) Teasers should first be used until they become active.
(f) A high percentage of fertile rams is necessary to serve all the ewes in a short period.
(g) Do not class breeding ewes by their hair.
(h) Eliminate all non-productive ewes.
Angora goat and mohair journal 9 (2)