Serum supplementation during in vitro fertilization of sheep oocytes influences blastocyst quality through the differential abundance of mRNA transcripts.

Incubation with estrous sheep serum (ESS) is required to induce in vitro capacitation of spermatozoa during in vitro fertilization of small ruminants. However, the effect of adding different serum concentrations in the fertilization media on the quality of resulting blastocysts has not yet been studied. Here, 298 sheep oocytes were co-incubated with capacitated spermatozoa with either 10% or 2% ESS. There were no differences between treatments in cleavage (10% ESS: 63.81 ± 5.87% and 2% ESS: 45.31 ± 5.87%) and blastocyst rates (10% ESS: 20.83 ± 2.12% and 2% ESS: 15.93 ± 2.12%). Nonetheless, in vitro-produced blastocysts from the 10% ESS treatment showed a higher transcript abundance of mRNAs involved in apoptosis (ITM2B and BCL2), antioxidant defence (GPX1) and growth-related imprinting (IGF2R). Our data suggest that ESS supplementation during in vitro fertilization can influence the quality of sheep embryos at later stages of development by increasing the transcription of developmentally important genes.

Variation of spermatogenic and Sertoli cell number detected by fine needle aspiration cytology (FNAC) in Iberian red deer during and out of the breeding season.

The aim of the present study was to evaluate spermatogenesis in Iberian red deer, a short-day seasonal breeder, using the fine needle aspiration cytology (FNAC) technique. Reports on spermatogenesis in deer are limited and here, for the first time, FNAC has been used to evaluate changes in such physiological process during and out of the breeding season. Testes were collected from 51 stags from November 2010 to February 2011. The Sertoli index and spermatic index were significantly higher during the breeding season than out of the breeding season (P=0.0477 and P=0.0125, respectively). A similar pattern was described by histological analysis, in which both Sertoli cell number per tubular cross-section and Johnsen score decreased significantly from the breeding season to the non-breeding season (P=0.0131 and P=0.0010, respectively). Data provided by FNAC were correlated with histology: the Sertoli index was positively correlated with Sertoli cell number per tubular cross-section (P=0.0015), whereas the spermatic index was correlated with the Johnsen score (P=0.0497). The results of the present study indicate that FNAC is a reliable technique to evaluate spermatogenesis in Iberian red deer and suggest that Sertoli cell number is not stable in these species, reaching highest values during the breeding season.

Diagnostic value of fine needle aspiration cytology in testicular disorders of red deer (Cervus elaphus): a case report.

We used fine needle aspiration cytology (FNAC) to diagnose Sertoli cell-only pattern and hypospermatogenesis in an Iberian red deer (Cervus elaphus hispanicus). Cytologic diagnosis was confirmed by histology and epididymal sperm analysis. We conclude that FNAC can be an important diagnostic tool in testicular diseases of wildlife.

Characteristics of the oestrous cycle of Iberian red deer (Cervus elaphus hispanicus) assessed by progesterone profiles.

This study examines the length of the oestrous cycle in 16 Iberian red deer females assessed by means of changes in progesterone concentrations, along with the changes in the profile of this hormone. Samples were collected three occasions per week from the week after calving (15 May to 15 June) up to May of the following year. The oestrous cycle lasted 19.57+/-0.29 days (range 10-27 d) calculated in 130 oestrous cycles examined. Progesterone titres did not rise above 0.5 ng/ml in the follicular phase, except in four samples. The maximum peak in progesterone concentration during the luteal phase remained above 1 ng/ml in most cases. Twenty-five percent of the individuals studied (4 out of 16) showed an oestrous cycle lasting shorter than the mean (15.2+/-0.30 days) before the start of the reproductive season, followed by a period of sexual inactivity. The standard progesterone profile in natural oestrous cycles rose from basal levels to those above 0.5 ng/ml four days after onset of oestrus, reached a peak of 1.71+/-0.07 ng/ml and then declined to less than 0.2 ng/ml after day 20. Following the rapid decline of progesterone after day 14, the concentration remained around the baseline level of 0.1 to 0.2 ng/ml during the immediate pre- and post-ovulatory phase of the cycle.