EFFECT OF SOME PRODUCTS OF HONEY BEE ON AGE AT PUBERTY AND FERTILTY OF MALE RABBITS

Abstract

The present work was carried out at Intensive Rabbit Production Unit, belonging to Consulting and Research Center, Faculty of Agriculture, Ain Shams University. The work was designed to investigate the effects of royal jelly (RJ) or/ and bee honey (H) on age of sexual puberty, semen quality and fertility of male New Zealand White (NZW) rabbits. Eighty pre-pubertal male NZW rabbits and 80 hybrid nonparous female rabbits were used in the present study. Male rabbits were randomly divided into 4 groups (20 bucks per group); bucks were administered orally with 0.5 mL of a solution/ kg body weight (b. w.), 3 times weekly for 6 weeks; which contained: 1) water for control (1st group), 2) 0.25 mL bee honey + 0.25 mL water (2nd group), 3) 200 mg royal jelly + 0.5 mL water (3rd group) and 4) 200 mg royal jelly + 0.25 mL honey + 0.25 mL water (4th group). All rabbit males were weighed weekly from the age of 60 up to 179 days old. The ages, at descending of testes into scrotum, at the beginning of fighting, at separation of penis from sheath, and at the first ejaculation were observed. At ages of 60, 90, 120 and 150 days old, 3 males from each group were sacrificed for anatomical and histological measurements. Blood samples were collected from the marginal ear vein of the experimental male rabbits using heparinized tubes. Blood plasma was separated by centrifugation at 700 G for 20 min and stored at -20ºC until analysis. Semen was collected artificially from each buck once weekly. Two successive ejaculates were collected and evaluated. Two unreceptive females were used as teaser for semen collection purpose. Eighty hybrid nonparous females were used for fertility test (20 females were inseminated artificially for each experimental group). The results of the present study showed that pre-pubertal NZW rabbits received RJ or/ and bee honey showed significant (P<0.05) earlier puberty age (earlier ages at testes descending into scrotum, separation of penis from sheath, fighting, first ejaculated sperm, appearance of secondary spermatocytes in testis, appearance of spermatid in testis, appearance of sperm in testis and epididymis); significant (P<0.05) increase of male reproductive system weight, accessory sexual gland weight, mean of testes weights, mean of testes index, mean of epididymis weights, mean diameter of seminiferous tubules, thickness of spermatogenic epithelium layer, mean diameter of epididymal duct and thickness of epididymal epithelium layer ; significant (P<0.05) increase of libido, ejaculate volume, mass motility, percentage of sperm progressive motility, motility index, sperm-cell concentration, seminal plasma fructose concentration, total sperm output, motile sperm concentration and functional sperm concentration compared to control group. On the other hand, percentages of dead and abnormal spermatozoa increased significantly (P<0.05) for control group compared to the other three groups. Blood plasma concentrations of testosterone and cholesterol increased significantly (P<0.05) for royal jelly or/ and bee honey groups compared with control. Otherwise, plasma concentrations of aspartate amino transferase (AST) and alanine amino transferase (ALT) differed non-significantly among groups. Rabbit bucks treated with royal jelly or/ and bee honey showed better fertility (higher conception rate and litter size) than control bucks. It is of importance to mention that better results were obtained from the fourth group which received both if royal jelly and bee honey, as compared to the other groups. In conclusion, the results of the present study showed that oral administration of royal jelly or/ and bee honey could be used beneficially to have earlier puberty age, improve semen quality and fertility of male NZW rabbits. This improvement was also mirrored on better liver functions as observed with normal concentrations of AST and ALT.