Does semen quality change after local treatment of seminal vesiculitis in stallions?

Inflammation of the seminal vesicle interferes with fertility and is a persistent problem that is difficult to treat. The aim of this study was to evaluate the semen quality of 5 stallions with seminal vesiculitis before and after local treatment. All stallions were endoscopically treated for seminal vesiculitis during 10 consecutive days. The glandular lumen was accessed and flushed with a Ringer Lactate solution prior to antibiotic infusion. The antibiotic was selected based on the antibiogram from bacterial culture of samples previously collected from the seminal vesicles. The kinetic parameters (total motility - TM; progressive motility - PM; and rapid sperm - RAP), plasma membrane integrity (PMI), percentage of leukocyte (LEUK) and colony forming units (CFU) of fresh semen samples were evaluated. Additionally, nitric oxide (NO) content in seminal plasma was measured. All parameters were assessed before (T0), one week after treatment (T1) and one month after therapy (T2). The sperm kinetics and plasma membrane integrity showed an improvement in T1 that didn't last until T2. Percentage of leukocytes and CFU decreased on fresh semen and NO decreased on seminal plasma at T1 but were similar between T0 and T2. The results demonstrate that one week (T1) of local treatment leads to an improvement in sperm quality. However, this was not maintained one month (T2) after therapy, as seminal parameters at this time are similar to the pre-treatment values (T0), indicating the recurrence of the disease one month after therapy.

Protocols using detomidine and oxytocin induce ex copula ejaculation in stallions.

Tricyclic antidepressives, such as imipramine, indirectly induce ejaculation by increasing the noradrenaline concentration, which triggers an α-adrenergic response, whereas α-adrenergic agonists, such as xylazine and detomidine, directly trigger ejaculation by activating the α-1 adrenergic receptors. Furthermore, serum oxytocin concentrations in stallions increase drastically before ejaculation, but decline immediately thereafter, implicating the role of this hormone in emission. The objectives of the present study were to: 1) compare the efficiency of various protocols for inducing ex copula ejaculation in stallions, 2) evaluate the benefits of including oxytocin in the protocols, and 3) compare the semen characteristics of ex copula versus in copula ejaculates. Nine protocols were used to induce ex copula ejaculation using various combinations of xylazine (X; 0.66 mg/kg, iv); oxytocin (O; 20 IU, iv), imipramine (I; 3 mg/kg, orally), and detomidine (D; 0.02 mg/kg, iv). Imipramine was given 2 h prior to the administration of α-adrenergic agonist (detomidine or xylazine) and oxytocin. If ejaculation did not occur within 10 min after treatment with an α-adrenergic agonist, a half-dose of the same product was injected. Twelve sexually mature stallions (6-26 y) were used; 9 of 12 stallions responded to the treatment. Two stallions responded to X or XO, four stallions responded to IX and IXO, one stallion responded to DO, and five responded to IDO. Stallions that responded to detomidine did not respond to xylazine. No stallion ejaculated in response to D, ID, or IO. Erections and masturbation occurred only in imipramine-treated stallions. Sperm quality was similar among all the protocols and was not significantly different from those in in copula ejaculates collected with an artificial vagina. In a separate trial, none of these protocols induced ex copula ejaculation in 2-3 y old stallions. The side effects included sialorrhea after imipramine administration in all the stallions and sedation after administration of xylazine or detomidine. In conclusion, the new protocol, IDO, and the traditional protocol, IX, had similar results, with IDO being a useful alternative protocol in stallions for which IX was not effective. Therefore, attempts using both the protocols are encouraged, as stallions that ejaculated upon administration of detomidine did not ejaculate when xylazine was administered, whereas those that responded to xylazine did not respond to detomidine.

Effects of coenzyme Q10 on semen cryopreservation of stallions classified as having good or bad semen freezing ability.

This study aimed to evaluate the antioxidant properties of coenzyme Q10 (CoQ10) during cryopreservation of semen obtained from stallions having good and bad semen freezing ability (GFA vs. BFA, respectively). Forty ejaculates (n = 20 stallions) were split into five centrifugation and five freezing extenders containing different concentrations of CoQ10 (0, 25, 50, 75 and 100 µmols/L). If CoQ10 was added to the centrifugation extender, the freezing extender had no CoQ10 added; similarly, if CoQ10 was added to the freezing extender, the centrifugation extender had no CoQ10. Semen cryopreserved on extenders containing no CoQ10 served as the control. After post-thaw total sperm motility (TM) assessments, the stallions were classified as GFA (i.e., decrease of ≤25% in TM, n = 7) or BFA (i.e., decrease of ≥40% in TM, n = 5). Stallions not fitting (n = 8) this enrollment criteria had samples discarded. After that, two straws for each extender were thawed at 37 °C for 30 s; one straw was immediately used for evaluation of sperm kinetics, plasma membrane integrity, non-capacitated spermatozoa, reactive oxygen species production, mitochondrial activity and lipid peroxidation. The second straw was kept at 37 °C for 30 min and subjected to the same assessments. Expectedly, sperm motility parameters were significantly lower for stallions with BFA. There were no effects of CoQ10 concentration or time for all parameters evaluated in the group with GFA when compared with the control extender (p > 0.05), except lipid peroxidation (p < 0.05). However, stallions with BFA had improved sperm parameters for samples processed with extenders containing CoQ10 (particularly 75 µmols/L) (p < 0.05), except for the reactive oxygen species production and mitochondrial potential (T0) in which there were no differences between the groups (p > 0.05). In summary, 75 µmols/L appears to be the optimal dose of Co-Q10, particularly, when added to the centrifugation extender.