Stimulation of Mating-Induced Uterine Contractions in the Bitch and Their Modification and Enhancement of Fertility by Prostatic Fluid

Normal and abnormal response to sperm deposition in female dogs: A review and new hypotheses for endometritis

In mammalian species there are significant physiological responses of the female reproductive tract to the deposition of sperm. These are particularly notable in species where sperm are deposited directly into the uterus, and function both to facilitate sperm transport to the sperm reservoir, and to eliminate introduced contaminants. In the bitch, sperm are deposited into the vagina and are rapidly transported through the open cervix. Sperm are then distributed around the uterus by uterine contractions such that transportation to the tip of the uterine horns occurs within 1 min of the start of mating. The main sperm reservoir appears to be the distal part of the utero-tubal junction which forms a pre-uterine tube reservoir. Sperm remain attached here by their heads to uterine epithelium and remain viable. In non-capacitating conditions sperm slowly detach from this site and this seems important to replenish the uterine tube reservoir, where sperm may re-attach to the epithelium. Post-ovulatory signals trigger capacitation changes and subsequent hyperactivated motility that is associated with detachment of sperm from both reservoirs; thus facilitating fertilization. After mating, a physiological post-mating uterine inflammatory response occurs, evidenced by an influx of polymorphonuclear neutrophils, increased uterine contractions, an increased uterine artery blood flow and a decrease of the resistance index indicating a short-duration vasodilation. Disturbance of this tightly regulated system has the potential to impact fertility by a failure of elimination of the introduced contaminants (such that a clinically-significant post-breeding endometritis ensues) but also by impairing sperm transport.

Small animal reproduction: Scientific facts versus dogmas or unverified beliefs

Small Animal Reproduction is a rather recent topic in the field of Animal Reproduction. Although some continuing educational societies aim to improve the level of general knowledge, published scientific facts are still limited, and there are many hypotheses or affirmations that remain unverified or even sometimes dogmatic or empirical. Through examples, this article reviews the main causes that may sometimes challenge a veterinary practitioner faced with a dog or a cat presenting reproductive problems. It could be difficult to orientate the diagnosis or the therapeutic approach, not knowing if what is found in the literature is a scientific proof or just an unverified affirmation. This problem may result from the fact that there are still physiological processes that remain unclear, but also that some common beliefs are based on old studies that have not been repeated or verifiedIn addition, to make it more challenging to seek for the information, there are unverifiedaffirmations,unclear nomenclature, clinical conditions which have not been standardized in the literature, clinical conditions mostly described through case reports, lack of studies on specific topics, areas of small animal reproduction that have been neglected by researchers, contradictory data or even studies that lack objectivity. The growing interest for research in Small Animal Reproduction will probably reduce the gap between unverified beliefs and scientific facts.

Freezing and storage effects on enzyme, electrolyte, and mineral compositions in canine prostatic fluid

BACKGROUND

There is a paucity of information about the storage stability of seminal plasma components in literature.

OBJECTIVES

This study investigates the potential effects of storage at -18.0°C on the enzyme activities and concentrations of selected electrolytes and minerals in canine prostatic fluid.

METHODS

Semen was obtained in fractions from ten male dogs, and the third ejaculate fraction was analyzed immediately after sampling and after storage at -18.0°C for 7 days. The following analytes were assessed: gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), sodium, potassium, total calcium, inorganic phosphate, magnesium, zinc, and copper.

RESULTS

Whereas electrolyte and mineral concentrations were not affected by freezing and 7 days of storage, effects on the enzyme activities were variable. ALP, AST, and LDH activities were significantly decreased (P < .05) in the post-thaw samples compared with the freshly prepared samples.

CONCLUSIONS

Because freezing and storage of seminal plasma at -18°C had an impact on the activity of some enzymes, analyses should be performed in fresh, not frozen samples.

Concentrations of minerals in the canine prostatic fluid

Current knowledge about the composition of the prostate fluid in healthy male dogs is limited and restricted to small case numbers. Furthermore, published data often vary significantly regarding sample processing and analytical methods. Therefore, we aimed to provide data on the composition of electrolytes and minerals in the canine prostatic fluid in a larger population (n = 30 dogs/samples) and to compare these results with the existing literature. Concentrations of sodium, potassium and copper analysed in our population were most consistent with those in the literature. Different to this, concentrations of total calcium, magnesium, zinc and inorganic phosphate varied. Whereas magnesium, zinc and inorganic phosphate seemed to depend on the analysis method, total calcium concentrations differed if centrifugation was performed or not. Our results clearly indicate a need for standardization of methods for analysis of seminal plasma components.

Current Review of Artificial Insemination in Dogs

Artificial insemination is the collection of semen from the male and the subsequent insertion of the collected semen into the female. Artificial insemination may be requested for several reasons, including inability to achieve a mating or due to the use of fresh chilled or frozen semen. A good understanding of the cycle of the bitch is imperative for maximizing pregnancy rates, as poor timing of insemination is the most common cause of subfertility in the bitch. Insemination techniques commonly undertaken in the bitch include vaginal insemination, surgical intrauterine insemination, and transcervical insemination.

The whole versus the sum of some of the parts: toward resolving the apparent controversy of clitoral versus vaginal orgasms

BACKGROUND

The nature of a woman's orgasm has been a source of scientific, political, and cultural debate for over a century. Since the Victorian era, the pendulum has swung from the vagina to the clitoris, and to some extent back again, with the current debate stuck over whether internal sensory structures exist in the vagina that could account for orgasms based largely on their stimulation, or whether stimulation of the external glans clitoris is always necessary for orgasm.

METHOD

We review the history of the clitoral versus vaginal orgasm debate as it has evolved with conflicting ideas and data from psychiatry and psychoanalysis, epidemiology, evolutionary theory, feminist political theory, physiology, and finally neuroscience.

RESULTS

A new synthesis is presented that acknowledges the enormous potential women have to experience orgasms from one or more sources of sensory input, including the external clitoral glans, internal region around the "G-spot" that corresponds to the internal clitoral bulbs, the cervix, as well as sensory stimulation of non-genital areas such as the nipples.

CONCLUSIONS

With experience, stimulation of one or all of these triggering zones are integrated into a "whole" set of sensory inputs, movements, body positions, autonomic arousal, and partner- and contextual-related cues, that reliably induces pleasure and orgasm during masturbation and copulation. The process of integration is iterative and can change across the lifespan with new experiences of orgasm.

A retrospective study of canine prostatic diseases from 2002 to 2009 at the Alfort Veterinary College in France

A retrospective study was used to investigate the incidence of prostatic diseases in a large population of dogs at Alfort Veterinary Hospital and to clarify epidemiologic features, which might be of a great help to veterinarians in managing and discriminating prostatic disorders. During the investigation period, a total of 72,300 male dogs (coming mainly from the Ile-de-France region) were registered in the Alfort Veterinary College database, and 481 of them (0.7%) were found to have prostatic disorder. The diagnosis was carried out on the basis of clinical signs and ultrasound findings. Among dogs experiencing a prostatic disorder, most frequently recorded diseases were benign prostatic hyperplasia (45.9%) and prostatitis (38.5%), followed by abscesses (7.7%), cysts (5.0%), neoplasia (2.6%), and squamous metaplasia (0.2%). Our study revealed an incidence of 0.3% of prostatic disorders observed in intact male dogs, except in the case of prostatic neoplasia. The mean age of the dogs experiencing prostatic disorders was 8.6 ± 3.2 years. This was significantly different (P < 0.001). Large dogs were significantly more affected by prostatic disorders (P < 0.05), except for prostatic neoplasia. A breed predisposition was suspected in German Shepherd (odds ratio [OR] = 2.1; 95% confidence interval [CI]: 1.5-2.9), Rottweiler (OR = 1.8; 95% CI: 1.2-2.7), American Staffordshire Terrier (OR = 3.8; 95% CI: 2.5-5.8), Berger de Beauce (OR = 3.7; 95% CI: 2.2-6.1), and Bernese Mountain Dog (OR = 2.5; 95% CI: 1.3-4.7).