Transactions of RHASS Volume 1940 - Page 064
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| Year | 1940 |
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| OCR Text |
AGRICULTURAL RESEARCH IN SCOTLAND IN 1939. BEING A BRIEF SUMMARY OF THE WORK AT THE SCOTTISH AGRICULTURAL RESEARCH STATIONS DURING THE YEAR. Readers dcsirin should write to the Director of the Station at which the in vestigution is being carried out. INSTITUTE OF ANIMAL GENETICS. UNIVERSITY OF EDINBURGH, WEST MAiNs ROAD. Pigs.—The extent to which carcase quality may be affected by the rate of growth and b shape of the growth curve has been inve raised under ordinary indoor feeding practice. It was found that loin and leg length tended to increase, and thickness of shoulder-fat to decrease, as weaning weight improved. Fast post-weaning growth was associated with increased thickness of back—fat, but the point most sensitive to differences in growth rate varied from one group of pigs to another. Breadth of eye-muscle appeared to be largely independent of growth rate. Thickness of back-fat was strongly dependent on loin length in one group of pigs but not in another, and in general the effects of growth rate seemed to depend on the underlying genetic differences in carcase conformation. With the object of estimating the contribution which outstanding performances by individual pigs might make to the pig population as a whole, an analysis has been made of the breeding policy adopted by a sample of pig breeders. The outstanding feature was the large proportion of breeding sows brought into herds from unrelated stock, in many herds amounting to more than half. This extensive interchange of blood would be expected to affect the development of strains of pigs of special characteristics. It is hoped to extend the investigation to a larger number of herds and to determine of bacon pigs y the general stigated in pigs 9 fuller information on. any of the subjects mentioned AGRICULTURAL RESEARCH IN SCOTLAND IN 1939. 117 whether the methods of breeding employed are the most efficient for achieving the desired ends. Poultry—Among the/fpoultry1 prpbleips investigated during - x x Ire several 0' genera in eres . ' I I tll(Cljlileafl‘rgffconcerned the length of the laying period in helpsé An examination of a large number of records Indicated ft an although hens will cease production at _varying 1tjimés 535” :11in to December it could be shown statistically't a tin Nibout birds have a strong tendency to finish egg—laying a (1)11: :1); the the same date in successive years. The day ont W iguable pullet produced her last egg of the season was nod atis) f last an indication of her characteristic time as the a e o ' * J r . egg’Tllite ($35131? osf the moult is one that affects all poultry breeders, for at this time there is a cessation of egg Erodllcglri]: until the new plumage is grown. In order to row s She lieht on the question whether a hen moults .ecausteated ceases to lay, or vice versa, the moult was studied in clas ‘r r males. The capon sheds feathers at all times of t 1;, ytghal,‘ but these birds were found to show‘ the most intense ela (Red casting in May and early June. lirom this it is cone1 undq that moulting will take place in the absence of any sfix a and that since this moult occurs earlier than in t e casethe the hen the function of1 thfetlsex glands is to postpone r 3 later )eri0( o e year. . Imfiiliiolrlilgtlddbe of tlie inbred lines of Brown Legliorns1 mam- tained at the. Institute varying amounts of female p unfillg: are being shown by the males. At the same time, in anp :0 inbred line, the females tend to develop spurs quite as sbro 1,, as cockerels of the same age. These characters are d.giig studied in order to obtain information as to the here 1 ary nature of sex differences. Rabbits—The mode of inheritance of fur properties portaiit in pelt production-has been further stiifidiegy fagétogs now appears almost certain that whilstnnod tyingf Ctor of play an important part there is one definite magior 13a t red a recessive nature which produces the. .des1red ne-hex u & pelt. On the other hand, it is now believed that t Earle isth series of factors, of a dominant nature, which contro engv Oftiifijther case of somatic segregation similar to thoge 1list reported has been sent to the Institute. Unfortunate y _b1;s rabbit had been killed, so no breeding tests were possi .01, but no similar cases had appeared in the stock fromtyvaiti a it came, and there is, therefore, no more eVideilice if} ind tendency for the condition was inherited than has )1 (11 ou in other cases reported. |
| Title | Transactions of RHASS Volume 1940 - Page 064 |
