الفهرس 
Alpha- chlorohydrinOnly 14 pages are availabe for public view
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Abstract
Laboratory as well as histological studies were carried out to test the effect of the male chemosterilant alpha-chlorohydrin (ACH) on five Egyptian vertebrate pests as a prelude to use this compound in the control of such pests. The five pests are the Egyptian fruit-bat (Rousettus aegyptiacus), the grass rat (Arvicanthis niloticus), the Egyptian spiny mouse (Acomys cahirinus), the lesser Egyptian gerbil (Gerbillus gerbillus), and Shaw’s jird (Meriones shawi). The last two rodent species have the potentiality to become agricultural pests in newly reclaimed desert areas. The compound, as far as I am aware, was not tested before, in the laboratory, with these pests.
The relative weights of the reproductive organs (testis, epididymis, vesicula seminalis, and prostate gland); count, motility and abnormalities of sperms, and the histopathological changes of the testis and epididymis of treated males were examined. These characters were compared with the corresponding ones in males of the control group to evaluate the effect of ACH on the fertility of treated males.
In R. aegyptiacus, ACH given by oral intubation has induced a significant antifertility response at a dose of 70 mg/kg for 4 days. Histological examination of the testis showed a thickened tunica albuginea, wide intertubular spaces, tubular vaculation and many seminiferous tubules with disorganized germinal epithelium. The tubules contained spermatogonia and primary spermarocytes with pyknotic nuclei associated with the absence of spermatids and spermatozoa. The cauda epididymis was almost devoid of sperms. There was a significant decrease in sperm count and motility, and a significant increase in sperm abnormalities.
In A. niloticus, ACH given by oral intubation has also induced a significant antifertility response at a dose of 70 mg/kg for 5 days. Histological examination of the testis of this group showed thickened tunica albuginea, wide intertubular spaces, large congested blood vessels, and atrophied seminiferous tubules with disorganized germinal epithelium. The tubules only contained spermatogonia and primary spermatocytes with pyknotic nuclei. Spermatids and spermatozoa were lacking. The presence of giant cells was also observed. The cauda epididymis was totally devoid of sperms, and was blocked with spermatids instead.
For practical application, ACH was presented to males as bait formulations in non-choice feeding cage tests. In Egyptian fruit-bats, it was presented for 4 days, and had an acceptability of 46.3%. Histological examination of the testis and cauda epididymis of treated bats showed that ACH had severely affected the spermatogenic process as in case of the force-fed group.
In grass rats, the bait formulation was presented for 5 days, and had an acceptability of 50.89%. Histological examination of the testis and cauda epididymis of treated rats showed that ACH had profoundly affected the spermatogenic process as in case of the force-fed group. Two and four weeks after the removal of the ACH bait formulation, there was no amelioration in the changes in the sperm parameters, or the testicular and epididymal histological alterations induced by this compound. This indicates that ACH has producec permanent sterility in treated males.
ACH, on the other hand, did not greatly affect the histology of the testes and cauda epididymides of treated males of each of A. cahirinus, at a dose of 50 mg/kg for 5 days or 70 mg/kg for 4 days; G. gerbillus at a dose of 50 mg/kg for 3 days or 60 mg/kg for 4 days; and M. shawi, at a dose of 50 mg/kg for 5 days, or 80 mg/kg for 3 days. It has, however, reduced the number of sperms by 54.4%, 85.6%, and 86.3% of its value in the control group of each of these rodent species, respectively. ACH has also increased the number of immotile sperms to 3, 4, and 2.5 times its number in the control group of each of these rodent species, respectively. A semi-field study is needed to verify the effect of ACH on the fertility of males of these three rodent species.