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Degenerative changes of the endometrium are directly related to age and fertility in mares. Chronic degenerative endometritis (CDE) is correlated with uterine fluid retention and reduced ability to clear uterine inflammation. Recent research in the areas of equine surgery and sports medicine has shown that platelet-rich plasma (PRP) treatment acts as an immunomodulator of the inflammatory response. Therefore, the aim of this study was to determine if the uterine infusion of PRP could modulate the local inflammatory response and modify the intrauterine NO concentrations after artificial insemination (AI) in both normal mares and those with CDE. Thirteen mares with endometrium classified as grade III on the histology (mares with CDE) and eight mares with endometrial histological classification I or II-a normal mares were selected to investigate the effect of PRP therapy. The mares were inseminated with fresh semen in two consecutive cycles in a crossover study design. Thereby, each mare served as its own control and the treatment was performed with intrauterine PRP infusion four hours after AI. The percentage of neutrophils in uterine cytology (CIT, %), uterine fluid accumulation observed on ultrasonography (FLU, mm) and nitric oxide concentration of uterine fluid (NO, μM) were analyzed before and 24 hours after AI. The results reported that mares with CDE (CIT, 68.3 ± 3.27, FLU, 10.7 ± 1.61) have a higher (P < 0.05) intrauterine inflammatory response after AI than normal mares (CIT, 24.4 ± 3.56, FLU, 0), but NO concentrations did not differ (P > 0.05) between categories of mares. In treated cycles with PRP, the intrauterine inflammatory response decrease (P < 0.05) in CDE mares (CDE: CIT, 31.4 ± 6.48, FLU, 5.5 ± 1.28; normal mares: CIT, 13.5 ± 4.31, FLU, 0) when compared with nontreated cycle (CDE: CIT, 68.3 ± 3.27, FLU, 10.7 ± 1.61; NM: CIT, 24.4 ± 3.56, FLU, 0), but did not modify NO concentrations in uterine fluid. Thus, we can conclude that PRP was effective in modulating the exacerbated uterine inflammatory response to semen in mares with CDE but did not reduce NO concentrations in intrauterine fluid.

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a b s t r a c tOne of the main factors known to influence quality and fertility of bovine cryopreserved semen is the extender used. In this matter, a great worldwide interest has been directed to the development of chemically defined media, free of animal origin products. The objective of the present study was to compare the efficacy of three bovine semen extenders: Tris-fructose (TRIS, control with 20% egg yolk), Botu-Bov s (BB; 20% egg yolk), and Botu-Bov s -soy lecithin (BB-L; 1% soy lecithin). Towards this aim, post-thaw computer assisted sperm analysis (CASA), sperm membrane and acrosome integrity were evaluated (Experiment 1). Additionally, cryopreserved samples were used in a fixed time artificial insemination program aiming to evaluate in vivo fertility (pregnancy per insemination-P/AI; Experiment 2). Despite the higher straightness and linearity found for samples cryopreserved in BB and BB-L when compared to those cryopreserved in TRIS, egg yolk based extenders provided higher total and progressive motilities, percentage of rapid sperms and intact membrane cells (P o 0.05). Furthermore, P/IA was higher in samples cryopreserved in egg yolk based extenders when compared to soy lecithin [TRIS ¼ 59.26 a (64/108), BB ¼ 62.37 a (58/93), and BB-L ¼36.45 b (35/96)]. Although soy lecithin represents an alternative for the development of chemically defined extenders with decreased risk of biological contamination, egg yolk based extenders are more efficient on the preservation of bovine post-thaw sperm viability and fertility.

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We address the problem of finding the optimal radiotherapy fractionation scheme, representing the response to radiation of tumour and normal tissues by the LQ model including exponential repopulation and sublethal damage due to incomplete repair. We formulate the nonlinear programming problem of maximizing the overall tumour damage, while keeping the damages to the late and early responding normal tissues within a given admissible level. The optimum is searched over a single week of treatment and its possible structures are identified. In the two simpler but important cases of absence of the incomplete repair term or of prevalent late constraint, we prove the uniqueness of the optimal solution and we characterize it in terms of model parameters. The optimal solution is found to be not necessarily uniform over the week. The theoretical results are confirmed by numerical tests and comparisons with literature fractionation schemes are presented.