From 2 to 4.5 months of age, 80 crossbred gilts were reared in a conventional grower unit where they were naturally exposed to mycoplasmal and bacterial pathogens that cause pneumonia and atrophic rhinitis. At 4.5 months of age, gilts were moved to environmentally regulated rooms (4.9 X 7.3 m) and assigned at random to 1 of 2 treatment groups: low aerial concentration of ammonia (4 to 12 ppm; mean, 7 ppm) or moderate aerial concentration of ammonia (26 to 45 ppm, mean, 35 ppm). Low concentration of ammonia was obtained by flushing of manure pits weekly, whereas moderate concentration of ammonia was maintained by adding anhydrous ammonia to manure pits that were not flushed. Gilts were weighed biweekly. Mean daily gain (MDG) was less (P < 0.01) for gilts exposed to moderate concentration of ammonia than for gilts exposed to low concentration of ammonia after 2 weeks in their respective environments. By 4 and 6 weeks, however, MDG was similar between the 2 treatment groups. After 6 weeks in these environments, 20 gilts from each treatment group were slaughtered, and prevalence and severity of lung lesions and snout grades were determined. At slaughter, body weight was greater (P < 0.01) in gilts exposed to low, rather than moderate, ammonia concentration (94.5 vs 86.8 kg; SEM, 3.3 kg). Percentage of lung tissue containing lesions (18 vs 12) and snout grade (2.8 vs 3.1) were similar between gilts exposed to low or moderate concentration of ammonia. The remaining 20 gilts in each treatment group were maintained in their respective environments, exposed daily to mature boars and bred at first estrus. Age at puberty was similar between gilts exposed to low or moderate concentration of ammonia (208 vs 205 days; SEM, 1.3 days), even though weight at puberty was less (P < 0.03) for gilts exposed to low concentration of ammonia than for gilts exposed to moderate concentration of ammonia (109.7 vs 118.2 kg; SEM, 4.5 kg).

An overall prevalence of 20.07% true anoestrus and delayed puberty in cattle was recorded out of 2202 gynaecological cases presented to the clinical complex and different clinical camps held at different locations of Kashmir valley over a period of three years (2005_2008). The highest prevalence of true anoestrus in cows was recorded in the 1st parity when they attained approximately 3 years of age and during autumn season.

Eight female piglets from each of three farrowed crossbred (75% Hampshire x 25% Local) gilts grouped as A, B and C were weaned at 28, 42 and 56 days respectively. Piglets of each weaned groups were divided into two sub-groups _ 'a' and 'b' consisting of 4 piglets in each. Piglets of sub-groups _ 'a' were supplemented with strategic mineral mixture while the piglets of sub-group 'b' were offered commercial mineral mixture. There was significant (P0.01) rise of serum oestradiol-17â at the pubertal oestrus compared to the levels before puberty in gilts. Oestradiol concentration did not differ significantly among piglets weaned at different days of age and between piglets supplemented with strategic and commercial mineral mixture. Serum progesterone was lowest during oestrus and highest on day 10 of the oestrus cycle in all the groups. Progesterone concentration in the piglets weaned at different days of age did not differ significantly. However, the level was found significantly (P 0.05) high in piglets supplemented with strategic mixture over the piglets supplemented with commercial mineral mixture.