Merino breed

Estradiol subsequently builds up in the blood and first (within 2 to 12 hours) reduces the levels of follicle-stimulating hormone (FSH) and the amplitude of LH pulses, then (within 12 to 48 hours) causes preovulatory surges of LH and FSH. The former promotes ovulation and development of a corpus luteum (reviewed in Martin et ah, 1986). Two compounds have been indicated in the effect of the odor of ram s fleece on LH secretion in anestrous ewes. These are 1,2-hexadecanediol and 1,2-octadecanediol. In Merino sheep at least, maximum stimulation of ovulation requires full exposure to a ram, such as fenceline contact in pastures. Olfactory cues from the ram s wool, presented in a facemask for the ewe, are ineffective by themselves visual and tactile stimuli are also important. The Merino breed does not rely as much on olfactory cues as other breeds of sheep (Pearce and Oldham, 1988). The effect is not necessarily species specific hair extract from male goats stimulates LH release in ewes. For this effect, the accessory olfactory system is not necessary (Signoret etah, 1989). 

Medium diameter wool iacludes sheep breeds of English origin, eg, southdown, hampshire, dorset, and cheviot, as well as crossbreds, eg, Columbia, targhee, corriedale, and polwarth, from interbreeding with merinos. Coarse diameter wool comes from sheep chiefly bred for mutton, eg, Lincoln, cotswold, and leicester. 

Pearce, D. T. and Oldham, C. M. (1988). Ovulation in the merino ewe in the breeding and anoestrous season. Australian Journal of Biological Science 41,23-26. 

In terms of economy, the yailau region is utilized as the main summer pasture. While the Karakul sheep graze mainly in the chul, the Merinos and fat-tailed breeds of sheep (including the Gissar breed) are pastured mainly in the yailau. Other agriculture is limited by low temperatures. 

Eor sheep, the data analysed by ARC (1980) showed a large effect of sex on EVg, but only a small effect of breed (Merinos having more fat and hence a higher EVg than other breeds), and no significant effect of rate of gain. Based on these data, AERC (1993) predicts that for sheep EVg can be predicted as follows ... 

The weight of wool produced by sheep varies considerably from one breed to another, and an average value is useful only as an example. The typical annual fleece production of a 50 kg Merino would be approximately 5.0 kg, of which about 3.0 kg (60 per cent) represents clean dry wool fibres, with the remaining 2.0 kg (40 per cent) being wool wax, suint, dirt and water. Wool wax is produced by the sebaceous glands and consists mainly of esters of cholesterol and other alcohols, along with the fatty acids normally found in glycerides. Suint, the secretion of the sudoriferous... 

The most obvious change in the character of the wool produced by copper-deficient sheep is loss of the characteristic crimp. This effect is much more noticeable in the Merino than in the British breeds, which do not normally produce wool with a marked crimp. The crimp becomes progressively less distinct as the animal s reserves of copper are used up, changing from normally crimped wool to straight, stringy or steely wool. A spectacular restoration of the crimp occurs when copper supplements are given. Further, the physical properties of the wool of copper-deficient sheep differ markedly from those of normal wool. The tensile strength is less and the elastic properties abnormal. ... 

Wool is a natural highly crimped protein hair fiber derived from sheep. The fineness and the structure and properties of the wool will depend on the variety of sheep fiom which it was derived. Major varieties of wool come from Merino, Lincoln, Leicester, Sussex, Cheviot, and other breeds of sheep. Worsted wool fabrics are made fiom highly twisted yarns... 

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