Alain Fontbonne

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).

Results of GnRH Agonist Implants in Oestrous Induction and Oestrous Suppression in Bitches and Queens

Over the last 10-15 years, long-acting GnRH agonists have become widely available. In the field of small animal reproduction, most recent studies have focused on the use of two compounds developed under the form of subcutaneous implants: azagly-nafarelin and deslorelin. Only the latter has been commercially available for use in male dogs, first in Australia and New Zealand, then in several countries of the European Union since 2008. Although officially marketed for male dogs, this compound has also been studied in bitches and more recently in queens. Some published papers or recent presentations at congresses--still unpublished--have focused on the use of GnRH agonists implants in females.

Estimated Pregnancy Length from Ovulation to Parturition in the Bitch and its Influencing Factors: A Retrospective Study in 162 Pregnancies

An accurate timing of parturition is very useful for managing canine parturition. It is generally accepted that parturition in bitches occurs between 64 and 66 days after the luteinizing hormone peak. In this retrospective study, we determined pregnancy length in different breeds and its influencing factors dating it from the estimated day of ovulation (EDO), defined as the day when peripheral plasma level of progesterone (P4) reaches 6 ng/ml. From January 2001 to December 2006, 162 pregnancies in 151 bitches of 53 different breeds were followed. Different parameters concerning the bitch, the litter, the type of semen and the type of reproduction were studied. The mean estimated pregnancy length in the bitch from EDO to parturition was 63.1±2.1 days. The main influencing factors for the pregnancies studied were the breed, the size of the bitch and the number of puppies within the litter.

Suppression of Fertility in Adult Dogs

Unfortunately, the overpopulation of dogs is still a problem in the majority of countries and even though surgical methods of sterilization, the most traditional and commonly used technique, have been intensively performed, the impact on the dog population is negligible. The neutering of companion animals as ovariohysterectomy (spaying) or orchidectomy (castration) has its limitations because of the cost, the need of a surgical environment and the risk of surgical and/or anaesthetical complications (ACCD 2009). In fact, surgical castration has been banished in some northern European countries and has limited acceptance in other countries. In a survey performed in Sao Paulo, Brazil, 56.5% of the owners of adopted shelter dogs were against the surgical procedure for different reasons (Soto et al. 2005). Currently, the options for contraception, defined as suppression of fertility are based on hormonal treatment. The treatments can be divided into analogues of gonadotropin releasing hormone (GnRH), progestins and androgens. Other possibilities of contraception are via the immunological system with vaccinations against GnRH, the luteinizing hormone (LH) receptor and the zona pellucida proteins. Finally, there is also the intra-epididymal or intratesticular injection of sclerosing substances in dogs. Mechanical devices to disrupt fertility are not used anymore due to the side effects. Suppression of fertility in adult dogs will be reviewed in order of use and possible impact on the dog population.

Presence of membranous vesicles in cat seminal plasma: ultrastructural characteristics, protein profile and enzymatic activity.

This study sought to verify the presence of membranous vesicles in cat seminal plasma by means of transmission electron microscopy and to identify protein profile and some of the enzymatic activities associated with these particles. The transmission electron microscopy observations showed the existence of different sized vesicular membranous structures of more or less spherical shape. These vesicles were surrounded by single-, double- or multiple-layered laminar membranes. The vesicle diameters ranged from 16.3 to 387.4 nm, with a mean of 116.5 ± 70.7 nm. Enzyme activity determinations showed the presence of dipeptilpeptidase IV, aminopeptidase, alkaline and acid phosphatase. To our knowledge, this is the first report that identifies and characterizes the membranous vesicles in cat seminal plasma. However, further studies are necessary to identify the exact site of production of these membranous vesicles in the cat male genital tract and to determine their specific roles in the reproductive events of this species.

UTILISATION D’IMPLANTS SOUS-CUTANÉS D’AGONISTES DE LA GNRH CHEZ LES CARNIVORES DOMESTIQUES POUR MAÎTRISER LA REPRODUCTION

The recent commercialisation in Europe of sub-cutaneous implants containing an agonist of the hypothalamic hormone GnRH, called deslorelin, has been done in the purpose of offering a chemical alternative to surgical castration in the adult male dog. The efficacy of these implants in this indication is real. They have an action on the endocrine function ( spectacular diminution of testosteronemia), on the exocrine function (alteration of sperm quality and infertility) and on the clinical evolution ( diminution of the size of the testis). The availability of these implants also gave rise to numerous other indications in the canine and feline species. Many recent publications, or even unpublished studies still going on, seem to show an interest in the improvement of unpleasant behavior potentially linked with testosterone in the male, but also to prevent fertility in the adult male cat and to prevent oestrus in the bitch or in the queen. Implantation of pre-pubertal animals to postpone puberty seems successful. In the adult bitch, induction of a fertile oestrus post-implantation is even possible, which bears a zootechnical interest. However, secondary effects, duration of action and further fertility after implantation are not well known at the moment and need to be further studied

L'HERPÈSVIROSE CANINE

Canine herpesvirus is an alphaherpesvirus responsible for an infectious and contagious disease associated with reproductive disorders. This virus may also be involved in the “kennel cough” syndrome. After contamination, the infected animal undergoes a seroconversion and becomes seropositive. Then, if its immunity is strong enough to control the infection, the virus becomes integrated to the cell DNA and the dog becomes seronegative. The virus becomes latent in various organs and may be reactivated at any moment under conditions of stress or immunodepression. This virus seems highly prevalent worldwide, although seroprevalence studies are not very reliable as many infected animals are seronegative at the time of blood sampling (frequent latency). Reactivation appears to be more frequent in large kennels due to stress and poor hygiene. Serological diagnosis is difficult to interpret and is more useful to characterise the overall status of a kennel rather than for individual diagnosis. Identification of viral DNA by PCR is currently the best method. Hygiene is a key factor in prevention. A vaccine is available in some countries, and seroprevention may be used in kennels at risk.