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    Changes in testicular development, ultrasonographic and histological appearance of the testis in buck kids immunized against LHRH using recombinant LHRH fusion protein
    (Reproduction of Domestic Animals, 2009) Ülker, Hasan; Küçük, Mürsel; Yılmaz, Ayhan; Yörük, Macit; Aslan, Lokman; de de AVILA, David M; Reeves, Jerry J
    This study was designed to evaluate the effectiveness of recombinant Ovalbumin-LHRL (OL) immunization on changes in testicular size, histological appearance and testosterone production in buck kids. Thirty native buck kids at 18 weeks of age were divided into three groups, control (n = 10), immunization (n = 10) and castration (n = 10) groups. Immunized animals received OL protein generated by recombinant DNA technology. Ultrasonographic and histological examinations of the testes were performed. Animals were slaughtered at 44 weeks of age. Semen and epididymides were evaluated for the presence of sperm cells. Immunized animals generated anti-LHRH antibodies. Testosterone production, testicular and accessory glands development and sperm production were suppressed in the immunized animals (p < 0.01). Semineferous tubule diameters decreased (p < 0.01), basal membrane of the tubule was thickened and hyalinized in immunized kids. Immunization affected ultrasonographic appearance of the testes drastically. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 18 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging; nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in buck kids and has a potential to be used as an alternative to physical castration. Further researches should be conducted to help assessing reproductive status of testes from ultrasound images.
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    The effectiveness of recombinant Ol fusion protein (Ovalbumin-LHRH-7) in supressing reproductive functions when injected in single-dose vaccination protocols with different adjuvants
    (Animal Reproduction Science, 2013) Karakuş, Ferda; Yılmaz, Ayhan; Hakan, Bünyamin; Stormo, Keith; Ülker, Hasan
    The objective of this study was to evaluate the effectiveness of recombinant LHRH fusion protein,Ovalbumin-LHRH-7(OL),using a single-dose vaccination protocol in combination with different adjuvants in suppressing reproductive functions in buck kids.For this pur-pose, either a mixture of free OL antigen and encapsulated OL antigen, or encapsulated OL antigen was used. Thirty-nine native buck kids at 12 weeks of age were divided into control (n=7) and treatment groups (n=8 bucks/group).The four treatment groups were formed according to the different vaccine formulations: Group Cp Greceived0.5mgfree OL protein to get her with 1. 0 mg of encapsulated protein with CpG adjuvant. Group mFCA received 0.5mg free OL protein together with 1.0 mg of encapsulated protein with modified Fre-und’s complete adjuvant. Group IS received 1.5 mg encapsulated OL protein with amix of inulin and saponin adjuvants. Group Ism FCA received 1.5mg encapsulated OL protein withamixofinulin, saponin and modified Freund’scomplete adjuvants. Scrotal circumference in CpG and mFCA groups were significantly smaller than that of Control, IS and ISm FCA groups (P<0.05). Numbers and percentage of bucks having spermatozoa in their ejaculate were significantly lowerin Cp G and mFCA groups (P<0.05). OL immunization completely suppressed sperm production, exceptone buck,in CpG and FCA groups (P<0.05).These results imply that it is possible to use OL protein in a single injection protocol for the purpose of immunocastration. Further investigation with a larger number of animals should be carried out to determine the longevity of response to a single injection.
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    Effects of supplementary feeding levels during mating period on reproductive performance of Karakaş ewes
    (Journal of Biological Sciences, 2004) Demirel, Murat; Kurbal, Ömer Faruk; Aygün, Turgut; Erdoğan, Sibel; Bakıcı, Yunus; Yılmaz, Ayhan; Ülker, Hasan
    A total of 78 Norduz ewes and their lambs were used in the study. Group 1 (control) was grazed only on pasture and Group 2, 3 and 4 were supplied with 200, 300, 600 g-1 head day -1 rolled barley, respectively, in addition to pasture. There were increases in live weights in Norduz ewes in response to supplementary feeding during feeding period (P<0.01). Feed supplementation during mating period did not affect reproductive traits. The effect of ewe age on the twinning rate and litter size (P<0.01) and fecundity (P<0.05) was significant. The mean lamb birth weight, weaning weight, daily live weight gain and survivability at weaning were 4.65 kg, 19.29 kg, 192 g and 96.43%, respectively. In conclusion, supplementary feeding in addition to grazing during breeding season affected live weight in Norduz ewes but not other reproductive traits. Further detailed studies should be carried out in order to determine the effects of supplementary feeding on reproductive traits in this breed.
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    Evaluation of one-shot vaccination protocol for supressing reproductive functions in rams using encapsulated ovalbumin-LHRH-7 protein
    (Indian Journal Animal Research, 2018) Yılmaz, Ayhan; Karakuş, Ayhan; Hakan, Bünyamin; Stormo, Keith; Ülker, Hasan
    The objective of study were to determine the effectiveness of Ovalbumin-LHRH-7 (OL) protein administered with cytosine guanine (CpG) adjuvant and Incomplete Freund’s Adjuvant (IFA), and used one-shot immunization (single-dose vaccination) protocol in which booster dose included in microspheres in rams. Fifty ram lambs at about a year old were used. Treatment groups receiving Ovalbumin LHRH and control contained 10 animals. They were stratified according to age (weeks), live weight and scrotal circumference size, and were randomly assigned to five groups. Scrotal circumference, sexual activities and the numbers of rams having sperm in the ejaculate were affected from treatment (P<0.05) depending on the dose and vaccination protocol. However, immunization did not affect live weight changes in any treatment groups (P>0.05). Findings clearly demonstrate that the effects of OL immunization on reproductive traits in yearling rams were prominent when it was administered at higher dose and classical one primary and one booster immunization as free protein form. Also we observed that the effect of higher and single dose of OL protein in encapsulated form on reproductive traits had the partial suppressing. CpG adjuvant along with IFA was proved to be an effective adjuvant and could be suggested to be used and alternative to FCA in hormone immunization.
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    LHRH fusion protein immunization alters testicular development, ultrasonographic and histological appearance of ram testis
    (Reproduction in Domestic Animals, 2009) Ülker, Hasan; Yılmaz, Ayhan; Karakuş, Ferda; Yörük, Macit; Budağ, Cemal; de AVILA, David M; Reeves, Jerry J
    This study was designed to evaluate the effectiveness of a luteinizing hormone-releasing hormone (LHRH) fusion protein immunization on reproductive traits in ram lambs including the changes in histology and ultrasonographic appearance of the testis. Thirty native ram lambs at 19 weeks of age were divided into control (C, n = 10), immunization (I, n = 10) and castration (E, n = 10) groups. Animals in immunization group were immunized against LHRH using ovalbumin-LHRH-7 (OL) protein generated by recombinant DNA technology as a primary and a booster injection at 19 and 23 weeks of age respectively. Animals were bled via jugular venepuncture at 2-week intervals to determine LHRH antibody and testosterone concentrations. Bi-weekly ultrasonographic examination of the testes was performed to determine the changes in ultrasonographic appearance as the age increased. Biopsied testicular tissues taken at 19, 29 and 41 weeks age were also evaluated. At 41 weeks of age, animals were slaughtered. Semen and epididymis were evaluated for the presence of sperm cells. Testicular development and sperm production were suppressed in the immunized animals. Seminiferous tubule diameters decreased, basal membrane of the tubule was thickened and hyalinized in immunized ram lambs. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 19 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging. Nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in ram lambs and has a potential to be used as an alternative to physical castration. Further research studies should be conducted to help assess reproductive status of testes from ultrasound images.