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Öğe Effect of SpermVital® technology on conception rate in repeat breeder multiparous dairy cows: preliminary results(Tubitak Scientific & Technological Research Council Turkey, 2019) Kocyigit, Alper; Uslu, Baris Atalay; Sendag, Sait; Treupel, Elisabeth; Wehrend, AxelThe aim of this study was to investigate the effect of SV technology on conception rates in repeat breeder multiparous dairy cows. Seventy-nine multiparous Holstein cows from a private dairy farm were used in the study. These animals were cows that had failed to conceive from at least 3 regularly spaced services (repeat breeders). Estrus cycles of the cows were synchronized by 2 injections of the PG analogue, administered 11 days apart. GnRH was applied 48 h after the second injection of PG. Twenty-four h after this administration, the animals were randomly divided into 2 groups, control and SV. The animals in the control group (n = 28) were inseminated with standard processed semen, and the cows in the SV group (n = 51) were inseminated with SV (R) technology processed semen. A lower pregnancy rate (35.5%) was determined in the control group than in the SV (47.1%) group. The difference between pregnancy rates in the groups was statistically significant (P < 0.05). We are at too early a stage to say that SV (R) Technology can fully respond to the deficiencies in herd management. This work may also lead to future studies into the use of more animal material.Öğe Effects of long-term release GnRH agonist "deslorelin" on testicular HSP expression, accessory sex glands and testicular functions in adult male rats(ELSEVIER SCIENCE INC, 2019) Eski, Funda; Cetin, Nebi; Uslu, Sema; Uslu, Baris Atalay; Sendag, Sait; Yoruk, Mecit; Naseer, Zahid; Wehrend, Axel; Shakeel, MuhammadThe objective of the present was to determine the effect of long-term release GnRH agonists "deslorelin" on suppression and restoration of testicular and accessory sex glands functions, and expression of HSP in testes of adult male rats. A group of twenty-eight male rats and fifty-six female rats were kept for eleven months. The male rats were subdivided into treatment (n = 18; deslorelin, an analogue of GnRH, 4.7 mg, S.C; six months) and control (n = 10; untreated), and the adult female rats were introduced with either treatment or control male rats at the 2nd, 6th and 11th months post implant insertion. At 6th month of deslorelin implants insertion, six male rats from treatment and five rats from control group were sacrificed. The remaining (twelve treatment and five control) male rats were sacrificed at 11 months. The testicular dimension were measured monthly in both treatment and control rats. The blood samples were collected for testosterone and HSP70 antibody, whereas, the testes and accessory glands were isolated for histological examination at each sacrificial time. The results showed that testicular dimension were significantly lesser in treatment group until 9 months post treatment. HSP70 protein expression was negligible at 6 months in treatment group but its intensity increased in spermatids 11 months of treatment similar to control group. Significantly lower testosterone concentrations with poor semen quality, and smaller litter size were observed in treatment group. The histological picture of accessory sex glands and seminiferous tubules shown a variable integrity in treatment group than control at 6 months implant insertion. In conclusion, the subcutaneous application of 4.7 mg of the GnRH-analogue deslorelin represents a practicable, like in the female rats, method to suppress testicular, accessory sex glands functions, testicular HSP expression and fertility in male rats. Moreover, the suppressive effects of deslorelin, continued until 11th months after removal of the implant. (C) 2019 Elsevier Inc. All rights reserved.Öğe The effect of GnRH on the pregnancy ratio in low-yielding local race cows: comparison of different injection times(Springer, 2020) Uslu, Baris Atalay; Kocyigit, Alper; Sendag, Sait; Gulyuz, Fetih; Wehrend, AxelThe objective of this article was to investigate the efficiency of GnRH administrations at different time points after induced luteolysis on pregnancy rates in low-yielding subfertile cows. One thousand six hundred and ten healthy and subfertile dairy cows of different ages and races were used in this study. Cows were randomly divided into 4 groups. Estrus cycles were synchronized by two, with 11-day intervals, injections of the prostaglandin F2 alpha-analogue (PG). The artificial inseminations (AIs) of all animals were achieved at the 72nd and 96th hours following the last PG injection. The animals in groups I (n 257), II (n 337), and III (n 675) were used for the administration of a single dose of GnRH at different time points. Accordingly, GnRH was applied at 48th, 64th, and 72nd hours following the last PG injection in groups I, II, and III, respectively. Group IV was accepted as a control without GnRH injection (n 341). The pregnancy rates in groups I, II, III, and IV after transrectal pregnancy examinations were found to be 89.88%, 91.09%, 83.25%, and 77.12%, respectively. In our study, maximal pregnancy rates could be obtained with GnRH injections performed at 48th and 64th hours following luteolysis induction (P < 0.001). There was a 6-8% decrease in pregnancy rates due to the injection of GnRH in the 72nd hour (P < 0.001). These dramatic losses and gains in pregnancy rates in our study emphasized the necessity of taking the time of injection into account when using GnRH to stimulate ovulation. It can be said that the success of GnRH stimulation of ovulation is directly related to the follicle wave dynamics at the time of injection point and the character of a dominant follicle.Öğe The Effects of Oral Progestagen Administration on the Fertility of Synchronized Goats During the Breeding Season(2024) Çetin, Nebi; Kuru, Mushap; Koca, Davut; Eşki, Funda; Uslu, Barış Atalay; Şendağ, Sait; Wehrend, AxelThe objective of this study was to assess the impact of oral progesterone (altrenogest) administered after mating on fertility in goats synchronized during the breeding season. A total of 47 Hair goats were included in the study. A progesterone-impregnated intravaginal sponges were administered for 12 days. On day 10 of intravaginal sponge administration, 480 IU pregnant mare's serum gonadotropin (PMSG) and 0.075 mg cloprostenol were injected intramuscularly to the goats. Animals were exposed to bucks for 12 hours after detection of estrus by the foraging buck. The goats were randomly assigned to two distinct groups: Group 1 (G1, n=23) and Group 2 (G2, n=24). G1 goats were orally administrated 4.4 mg of altrenogest per day for 30 days after mating. G2 goats served as controls. Pregnancy examinations were performed by transrectal ultrasonography on the 30th and 42nd days after mating. Blood samples were taken from one day after mating to 30 days (3-day intervals). Statistical analysis comparing G1 and G2 revealed no significant differences between the groups regarding progesterone concentrations, conception rate, pregnancy rate, lambing rate, multiple birth rate, fecundity, and litter size (p>0.05). In conclusion, this study revealed that oral progesterone use had no impact on fertility parameters. Moreover, further research is warranted to explore the efficacy of various oral progesterone analogs.
