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Sheep - AgRIS

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iv) Altitude<br />

High altitude and poor nutrition are deleterious to fertility in rams (Easley, 1951).<br />

v) Shelter/Housing<br />

Tiwari and Sahni (1970) have reported that there was no beneficial effect of underground<br />

housing on semen production of Rambouillet rams during summer months. It was indicated that<br />

unless the maximum environmental temperature was brought down to 7080°F artificially, there<br />

was no scope for obtaining good quality of semen from exotic rams with conventional sheds<br />

during hotter part of the year under semi-arid conditions.<br />

Tiwari and Sahni (1972) have obsened that the provision of Shelter/Housing has no<br />

beneficial effect on sexibido and seminal attributes in cross-bred hoggest males.<br />

vi) Disease<br />

Any infection such as foot rot or abscess which might cause general febrile condition, will<br />

result in seminal degeneration (Gunn et al., 1942). Morley (1948) reported that scrotal fly strike<br />

may not necessarily impair fertility. Engela (1948) reported incidence of dpididymitis,<br />

varicocele, scrotal tumours and other diseases of male genitalia which cause semen<br />

degeneration.<br />

Andreevskii (1940) observed that the main cause of semen abnormality in 40, 976 adult<br />

rams was chronic orchidoepididmymitis. Of these about 15% of rams showed morbid and<br />

degenerative changes in the testes, mostly in epididymis.<br />

vii) Shock<br />

Webster (1952) observed that in New Zealand, a cold southernly wind during night<br />

rendered 18 rams infertile over night and the condition persisted for remaining period of the<br />

breeding season. He also observed from the past record that abnormally low lambing<br />

percentage was related to a sudden exposure to stormy weather during the mating season.<br />

Dun (1956) recordedtemporary infertility in rams, dueto damp and marshy conditions<br />

which led to seminal degeneration associated with flabbiness of the testis. The condition was<br />

accompanied by warm humid weather and mosquito plague, shortly before mating.<br />

Sahni and Roy (1972) reported that since the differences in semen characters of indigenous<br />

breeds of sheep in different seasons were small, the cold shock test at 5°C or 15°C could not be<br />

considered of any assistance as a method of testing the semen quality.<br />

viii) Feeding<br />

Honmode et al (1971) have examined sexual desire and various seminal attributes of<br />

Chokla rams maintained on four different feeding sehedule. It was found that sexual desire and<br />

all the seminal attributes studied was higher in group receiving cenchrus + Conc. mixt. and<br />

cenchrus + cowpea hay than those receiving only cenchrus + Pala leaves and cenchrus + guar<br />

follice.<br />

Feeding thyroproteins has not produced benefical results in rectifying the seasonatect on<br />

rams semen.<br />

It is reported that semen from rams fed cotton seeds and phospholipids, freeze better.<br />

Similarly the level of certain minerals, vitamins and formones also do play role on the freezing<br />

of the spermatozoa for successful revival. Certain workers are of the opinionthat certain<br />

chemicals in the seminal plasma are harmful in the process of freezing and hence tried to freeze<br />

the washed spermatozoa in artificially prepared extenders but the results are equally<br />

disappointing. Feeding, housing and other managemental factors like vaccination, dipping,<br />

exercise, shearing, incidence of dieases like bluetongue, sheep pox, affect the semen quality<br />

and the composition of seminal plasma and in turn the freez ability and fertility. Avoiding<br />

sudden change of temperature before equilibration, unnecessary exposure to oxygen and bright<br />

light, adhering to strict asepsis at every step using tripple glass distilled deionized water, use of<br />

pure and nontoxic chemicals are some factors which deserve attention in the venture of deep<br />

freezing of ram semen.<br />

406

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