Browsing by Author "DeAvila, D. M."

Now showing 1 - 2 of 2

The Effect of Immunization Against Lhrh on Carcass Characteristics in Coloured Mohair Goats
(indian veterinary Journal, 2008) Kucuk, M.; Bolacali, M.; Ulker, H.; DeAvila, D. M.; Reeves, J. J.
Immunizing farm animals against luteinizing releasing hormone (LHRH) is an alternative to castration (Thompson, 2000). It suppressed testicular development and reduced sexual activities in domestic species (Adams and Adams, 1992). It has been reported that immunizing male animals against LHRH had no negative effect on carcass quality (Kiyma, et al., 2000 and Huxol et al., 1998). A recombinant fusion protein, ovalbumin-LHRH-7 was developed (Zhang et al., 1999). The immunocastrate effect of this recombinant protein was demonstrated in farm animals (Ulker et al., 2003). The aim of the present study was to compare the carcass traits of goat kids intact, surgically castrated and actively immunized against LHRH using ovalbumin-LHRH-7 fusion protein.
Gnrh or Ecg Treatment Fails To Restore Reproductive Function in Gnrh Immunized Ewes
(Elsevier Science Bv, 2009) Gokdal, O.; Atay, O.; Ulker, H.; Yarali, E.; Helva, I. B.; DeAvila, D. M.; Reeves, J. J.
This Study was designed to evaluate the potential of using eCG or GnRH in restoring reproductive functions in GnRH immunized ewes. Thirty-three multiparous Kivircik ewes were randomly assigned into either control group (n = 11) or immunization group (n = 22). Ewes were immunized against GnRH by injecting witha cocktail of ovalbumin-LHRH-7 (ovalbumin-GnRH-7) and thioredoxin-LHRH-7 (thioredoxin-GnRH-7) fusion proteins generated by recombinant DNA technology in April. 500 IU eCG or 0.008 mg GnRH analogue was used to induce ovulations. Serum GnRH antibodies were present in animals of the immunized group beginning the second week after the first immunization and maintained throughout the Study (14 months). Immunization caused anestrus in immunized ewes. eCG or GnRH analogue administration given after 14 days progestagen (20 mg fluorogestone acetate, FGA) treatment during breeding season (mid July) did not induce ovulation in these ewes. Two more attempts with single or multiple eCG injections failed to induce ovulation in this group as well. It appears that the gonadotropin stimulation was not of adequate time since neither eCG nor GnRH administration was able to restore reproductive function in immunized animals. The immunization effect lasted more than a year. These results suggest that GnRH immunization exerts its effect via the hypothalamo-pituitary axis and that more than such stimulation is required to overcome the reproductive suppression. (C) 2008 Elsevier B.V. All rights reserved.