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This experiment was conducted to study variations of serum testosterone and seminal characteristics of Markhoz male goats. Blood samples were obtained via jugular vein, and semen was collected by using an artificial vagina from 14 fertile male goats (2–3 years of age), at 15-day intervals starting on 15 July and ending on 30 October 2010 (during breeding and non-breeding season). Semen volume, total sperm (volume×concentration), live sperm (%), abnormal sperm (%) and semen pH were significantly superior during the late summer and early autumn (breeding season). Variation of sperm density, motility and progressive motility was not significant during the sampling period. The results presented show that the lowest and highest levels of lactate dehydrogenase in the seminal plasma were recorded in late October (2.82 U/ml) and in late August (4.81 U/ml), respectively. Moreover, the study indicated that the serum testosterone concentration was higher during late summer and early autumn (p<0.05) than at any other of sampling period. There were negative correlations between volume and sperm density (−0.135, p<0.05), and positive correlations between volume and percentage live sperm (0.224) and percentage progressive motility (0.194, p<0.01). Sperm density was correlated with live sperm (0.200, p<0.05) and progressive motility (0.202, p<0.01). The correlation between live sperm and progressive motility was 0.554 (p<0.01). Furthermore, the results in this study indicated a significant positive correlation between live sperm and LDH (0.450) and a negative correlation between sperm density and LDH concentration (−0.272) (p<0.01). Significant, but positive correlations were found between sperm motility and LDH (0.542) and testosterone concentration (0.522), respectively (p<0.05). In conclusion, this study demonstrated that the best obtained semen was collected in late summer (during decreasing photoperiod) and early autumn (September and October). This also coincides with the natural breeding season of Markhoz goats in Iran.

Thermal stress in cattle results in major decreases in dairy production and reproduction. A study was designed to evaluate the influence of temporary cooling on pregnancy rate in Holstein heifers during summer heat stress. Estrus was synchronized with two injections of prostaglandin [Formula: see text] (PG), administrated 11 d apart, and all heifers were housed in a shaded enclosed structure at the time of the second PG injection. After estrus detection, heifers were randomly divided into three groups: Control (C; n = 30), Sprinkler (S; n = 30) or Sprinkler and Fan (SF; n = 30). Rectal temperatures were measured 2.5 hours before AI, at the time of AI, and 1.5 and 3.5 hours after AI. Group C heifers receive no further treatment, but heifers in S and SF groups were exposed to short-term cooling from 2 hours before until 2 hours after AI with a sprinkler (S) or sprinkler and a fan (SF), respectively. Estrus detection and AI were performed by a single skilled technician; semen was from a bull of known fertility. Rectal temperature did not differ among groups 2.5 hours before AI, but at the time of AI was lower (P < 0.05) in SF group (39.3 +/- 0.0 degrees C) than in S (39.5 +/- 0.0 degrees C) and C (39.9 +/- 0.1 degrees C) groups which also differed (P < 0.05). At 1.5 and 3.5 hours after AI, rectal temperature remained lower in SF group (38.9 +/- 0.0 and 38.7 +/- 0.0 degrees C, respectively) than in the S (39.4 +/- 0.0 and 39.2 +/- 0.0 degrees C, respectively) and C (39.3 +/- 0.0 and 39.3 +/- 0.0 degrees C, respectively) groups, which no longer differed. Pregnancy rate following AI was higher (P < 0.05) in SF group (56.7%) than in the C group (23.3%) with the S group (40%) intermediate and not different from either. The present study results indicate that cooling of dairy heifers for a short time before and after AI, especially with sprinkler and fan, can increase pregnancy rate during heat stress.

1. The objectives of this study were to compare the hatchability, chick body and internal organs weights and plasma testosterone concentration of hatchlings after in ovo administration of royal jelly (RJ) on d 7 of incubation. 2. Fertile eggs (n = 150) were injected into the air sac or yolk sac with 0.5 ml normal saline solution or normal saline and pure RJ. The eggs were randomly divided into 5 groups of 30 eggs each: NC, control eggs receiving no injection; ASA, air sac-injected eggs given normal saline solution; ARJ, air sac-injected eggs injected with pure RJ; YSA, yolk sac-injected eggs receiving normal saline solution and YRJ, yolk sac-injected eggs given pure RJ. 3. Injection of RJ significantly decreased hatchability (46.7%) compared with injection of saline solution (68.3%). Hatchability was lower in ARJ (33.3 %) and YRJ (60.0%) groups than in the NC group (90.0%). Hatchability in ASA (70.0%) and YSA (66.66%) groups were comparable to the NC group. 4. In ovo injection of RJ into both sacs increased chicks' absolute and relative body, heart, liver and testes weights compared to the control group whereas plasma testosterone concentration was similar among the different groups. 5. It was concluded that in ovo injection of RJ may be an effective method to increase the body weight of hatched chicks as an absolute value (CWT) and chicks' internal organ weights.

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