Ž .
6–7 years old Novoa, 1970; Arthur et al., 1985 . Inadequate body weight caused by Ž
lack of sufficient food appears to be the cause of delayed puberty in the camel Chatty, .
1972 . Nutrition seems to play a vital role in the various physiological events for the attainment of sexual maturity and in the reproductive process. The faster an animal
Ž .
grows, the earlier it will reach sexual maturity Maynard et al., 1979 . In cattle, puberty Ž
. occurs at a particular liveweight bodyweight or body size rather than a fixed age.
Meanwhile, in sheep, it is complicated by their seasonal breeding pattern in Europe Ž
. McDonald et al., 1988 . Undernutriton delays puberty in both male and female virgin
camels and, if severe, can cause retrogressive changes in the sexual organs after their Ž
. full development Maynard et al., 1979 .
3. Breeding season
Camels are considered seasonal breeders. However, information about the breeding season in the dromedary is rather conflicting. Thus, the breeding season has been
Ž .
reported from March to August in Sudan Musa and Abusineina, 1978a , December to Ž
. Ž
March in Pakistan Yasin and Wahid, 1957 , November to March in India Matharu, .
Ž .
Ž 1966 , April to May in Somalia Mares, 1954 , December to May in Egypt Shalash,
. Ž
. 1965 , December to March in Tunisia Minoia et al., 1992 , and October to April in
Ž .
Saudi Arabia Abdel-Rahim and El-Nazier, 1990; Al-Eknah et al., 1997a,b . Decreasing Ž
daylength appears to be the stimulus to seasonality Merkt et al., 1990; Musa et al., .
Ž 1993 . In camels near the equator, factors such as rainfall Bono et al., 1989; Arthur,
. Ž
. 1992 , nutrition, and management Wilson, 1984 may override the effects of photope-
Ž .
riod and allow breeding to occur throughout the year Arthur et al., 1985 . Therefore, Ž
with a continuous supply of sufficient food, camels can be truly polyoestrus Arthur et .
al., 1982 . The main trigger for Arabian camel sexual receptivity is rainfall and the Ž
. subsequent availability of improved nutrition Cristofori et al., 1986 . Mature male
dromedary camels show also a seasonal sexual activity. The rutting season occurs during Ž
. spring in Egypt Abdel-Raouf and El-Naggar, 1964 , from November to February in
Ž .
India Khan, 1971 and from mid-January to the end of May in the Turkiman dromedary Ž
. Abdunazarov, 1970 . Higher testosterone levels and active poll glands have been found
Ž during the rutting season Yagil and Etzion, 1980; Tingari et al., 1984; Agarwal and
. Khanna, 1990 . Spermatogenesis continues throughout the year in male camels, but at a
Ž .
higher rate during the cooler months of the breeding season Abdel-Raouf et al., 1975 . Hyperprolactinaemia has been proposed to cause reduced libido and fertility during the
nonbreeding seasons of the male camel, due to the suppressive effect of the high Ž
. prolactin levels on secretion of FSH and LH Azouz et al., 1992 . GnRH treatment has
been used to stimulate sexual activity in normal males outside the breeding season Ž
. Moslah et al., 1992 .
4. Ovarian dynamics
