Testicular cytology indicates differences in Sertoli cell counts between "good freezer" and "poor freezer" bulls.

In artificial insemination, poor quality of semen unsuitable for cryopreservation and susceptibility of spermatozoa to cryodamage in crossbred bulls have been a matter of concern. Present study was designed to identify the testicular cytology indices that might be used to predict the semen quality and cryotolerance of spermatozoa in bulls. Based on the ejaculate rejection rate and sperm cryotolerance, bulls (Holstein Friesian X Tharparkar crossbred) were classified into either good (producing good quality semen with spermatozoa having good cryotolerance; n = 4) or poor (producing poor quality semen with spermatozoa having poor cryotolerance; n = 4). Testicular cytology was studied in all the 8 bulls using fine needle aspiration technique. Testicular cytology of good bulls and poor bulls differed significantly. The proportion of Sertoli cells was significantly higher in good bulls (25.3 ± 1.6) compared to poor bulls (11.0 ± 0.8). The Sertoli cell index was 46.1 ± 5.0 in good bulls while it was only 13.8 ± 1.3 in poor bulls. The cut off values, as determined using Receiver Operating Characteristics analysis, indicate that the bulls having testicular cytogram comprising of < 15.5% Sertoli cells, < 24.3 Sertoli cell index and > 4.0 spermatogenic cells to Sertoli cell ratio might be a poor bull in terms of semen quality and cryotolerance of spermatozoa. The proportion of Sertoli cells in the testicular cytology had positive (P < 0.05) relationship with semen quality and cryotolerance of spermatozoa.

Analyzing Cell-free Genomic DNA in Spent Culture Media: Noninvasive Insight into the Blastocysts.

A commonly accepted standard protocol for noninvasive techniques for the genetic evaluation of an embryo remains elusive due to inconclusiveness regarding the volume of spent media to be acquired and the possibility of acquiring the same for subsequent analysis. Single embryo culture is imperative for standardizing noninvasive preimplantation testing using cell-free DNA (cf-DNA) released by individual developing embryos. This study aims to compare the development dynamics of single-drop embryonic culture against with group embryonic culture to establish a standardized protocol for noninvasive Preimplantation Genetic Testing (PGT) in bovine. A total of 239 cumulus-oocyte complexes were aspirated and subjected to in vitro maturation and fertilization. Among these, 120 embryos of day 3 were transferred to single-drop culture until the blastocyst stage. The single-drop culture drops were prepared using microdrops of 30 µL. At the blastocyst stage, spent media from all single-drop embryos were utilized for extracting cell-free genomic DNA to standardize the protocol. The blastocyst rate indicates no significant difference between the two culture methods, suggesting that single-drop culture is suitable for the process. Additionally, the extracted spent media yielded sufficient quantities of cf-DNA, supporting its potential use for PGT ( p < 0.05). These findings support the hypothesis that single-drop embryo culture is a viable method for cf-DNA extraction and confirm the potential of using DNA fragments from spent media as a reliable source for noninvasive PGT.

Effect of estradiol and cloprostenol combination therapy on expulsion of mummified fetus and subsequent fertility in four crossbred cows.

Four crossbred cows with mummified fetus were utilized for the study. The cows were subjected to gynecological examination and based on the findings the cases were diagnosed as mummified fetus. The cows were treated with 2 mg estradiol valerate and 500 µg cloprostenol and were examined every 12 hr after 24 hr of the treatment for cervical dilatation and other signs related to fetal expulsion. The time duration between treatment and starting of cervical dilatation ranged from 48 to 58h (53.00 ± 2.08 hr). Complete dilatation of cervix was observed after 70.00 ± 2.94 hr post treatment (Range = 64-76 hr). The mean fetal crown-rump length (CRL) was 31.5 cm, which ranged from 27.5 to 38 cm. The number of cotyledons in pregnant horn also showed wide variation (Range 24-38 numbers) with mean ± SE of 30.3 ± 3.07 numbers. In the placenta of three animals irregular shaped large adventitious cotyledons were observed in the inter-cotyledonary areas. Out of the four animals treated, three animals were conceived within three estrous cycles and one animal had cystic ovary in the next cycle and was not conceived even after four cycles. It was concluded that the estradiol and prostaglandin F2α (PGF2α) combination therapy was effective for expulsion of mummified fetus in crossbred cows without affecting much on future fertility.