Chiara Milani

Clinical use of deslorelin for the control of reproduction in the bitch.

This study was conducted to evaluate clinical efficacy of deslorelin for inhibiting reproduction in the bitch. Ten adult healthy bitches or bitches with mammary neoplasia for which owners were requesting suppression of cyclicity without performing gonadectomy were administered a 4.7- or a 9.4-mg deslorelin implant subcutaneously. The first implant of deslorelin was administered in anoestrus (n = 5) or in dioestrus (n = 5). Treatment was repeated every 5 months for as long as necessary based on the clinical situation of the dog and owners desires. Some of the bitches implanted in anoestrus came in heat within 4-15 days after treatment, while none of the bitches implanted in dioestrus showed heat during treatment. Suppression of reproductive cyclicity was successfully achieved in 6/10 bitches for 1-4 years. No behavioural and local/general side-effects were observed in any of the treated bitches. The 4.7-mg deslorelin implant may work well for suppression of cyclicity provided that it is administered in dioestrus and at intervals of 4.5 months. A 9.4-mg implant may be more suitable for this use although its efficacy may also be shorter than 12 months. Owner compliance is an important limiting factor.

Clinical Use of Testicular Fine Needle Aspiration Cytology in Oligozoospermic and Azoospermic Dogs

Clinical investigation of canine testicular function is complicated by the difficulty in the evaluation of seminiferous tubules. Until recently, testicular biopsy was the only diagnostic option for dogs with persistent oligo/azoospermia. In human andrology, testicular fine needle aspiration (TFNA) is currently considered a useful method in the evaluation of azoospermia and severe oligozoospermia, and has long replaced classical biopsy to evaluate spermatogenesis. In order to verify its diagnostic efficacy for the clinical approach to canine oligo- or azoospermia, TFNA was performed in seven adult (two oligozoospermic and five azoospermic) dogs. After sedation, a fine (21-23 gauge) butterfly needle connected to a 50-ml syringe was inserted into each testicle; strong suction was applied and the aspirated fluid squirted on a glass slide, smeared out, air-dried and stained with a modified May-Grunwald-Giemsa. Under light microscopy, Sertoli cells (all those found in each investigated field) and spermatogenic cells (n = 100) were counted on each smear in order to differentiate spermatogonia, primary spermatocytes, secondary spermatocytes, early spermatids, late spermatids and spermatozoa, and calculate their relative percentages. Cytological analysis showed the following testicular pictures: normal spermatogenesis (compatible with obstruction of the seminal ducts), hypospermatogenesis, maturative disturbances and Sertoli cell-only syndrome. Two dogs with an obstructive lesion were treated with corticosteroids; one of them recovered and sired two litters of puppies.

Misuse of antimicrobials and selection of methicillin-resistant Staphylococcus pseudintermedius strains in breeding kennels: genetic characterization of bacteria after a two-year interval.

Methicillin-resistant Staphylococcus pseudintermedius (MRSP) strains have been isolated from dogs with increasing frequency; prolonged or excessive use of antimicrobials is associated with the selection of MRSP, and misuse of antimicrobials is frequent in breeding kennels. This study was carried out in two breeding kennels (A and B) in which we had isolated MRSP in 2008: the aim was to assess colonization of previously positive bitches and of other bitches sharing the same environment and to assess the genetic profile of both the old and the new strains [spa typing, staphylococcal cassette chromosome mec (SCCmec) typing and Pulsed-field Gel Electrophoresis (PFGE)]. Six animals from Kennel A (two from 2008) and eight from Kennel B (one from 2008) were tested: 16 MRSP strains were isolated only from bitches housed in Kennel B. Old and new isolates were mecA positive, resulted spa type t02 and carried SSCmec II-III. PGFE showed that all isolates were related and belonged to the main clone lineage dominating in Europe, ST71-J-t02-II-III. Kennels A and B differ in the use of antimicrobials, which has been reduced over time in Kennel A, while has remained excessive in Kennel B, where many agents belonging to different classes (third-generation cephalosporins, fluoroquinolones, macrolids) are administered to dogs, without veterinary supervision, especially around parturition. Misuse of antimicrobials is the key factor for the selection of MRSP strains in healthy dogs and for their persistence over time. Dog breeders should be aware that infections caused by multiresistant bacteria have very limited therapeutical options and represent a huge challenge for animal health.

Semen quality and onset of sterility following administration of a 4.7-mg deslorelin implant in adult male dogs.

The purpose of this study was to define (i) the interval between treatment and sterility, and (ii) semen quality in male dogs administered a 4.7-mg deslorelin implant. Six healthy, adult dogs of various breeds and body weights were implanted with deslorelin (Suprelorin, Virbac) and followed every 2 weeks with semen and blood collections. Semen quality remained stable or even improved during the first month following treatment and then showed a progressive decline until the end of the study, except for sperm morphology, which was unaffected by the treatment. Complete sterility was achieved on post-treatment days 70, 84, 60, 23, 51 and 40 for dogs 1 to 6, respectively. The 4.7 mg deslorelin implant caused a significant (p < 0.05) decrease in serum testosterone as well as sperm motility. Our results (i) confirm the efficacy of deslorelin in causing reversible sterility in male dogs, (ii) confirm and provide details about endocrine and seminal parameters involved in this process and (iii) contribute to define the interval between treatment and achievement of complete sterility. Practitioners should be aware that such interval may be longer than 2 months in some cases, and that fertility may actually be increased during the first 2-4 weeks post-treatment.

Pregnancy and conception rate after two intravaginal inseminations with dog semen frozen either with 5% glycerol or 5% ethylene glycol

The primary goal of this study was to compare the effects of 5% ethylene glycol (EG) and 5% glycerol (G) on fertility of frozen-thawed dog semen following intravaginal insemination. The sperm-rich fraction of the ejaculate of three male dogs was collected, pooled and divided into two aliquots, and then frozen with a Tris-glucose-egg yolk-citric acid extender containing either 5% G or 5% EG. A total of 10 bitches were inseminated twice, five with G-frozen-thawed semen and five with EG-frozen-thawed semen; intravaginal inseminations were performed the 4th and the 5th day after the estimated LH peak; four straws, thawed in a 37 degrees C water bath for 1 min and diluted in a Tris buffer, were used for insemination (200 x 10(6) spermatozoa); the insemination dose was introduced in the cranial vagina of the bitch using a sterile plastic catheter. Ovariohysterectomy was performed in all bitches between days 29 and 31 after the calculated LH surge, and pregnancy status, and the number of conceptuses and corpora lutea were recorded. All bitches were pregnant. Neither the number of conceptuses, nor the ratio of conceptuses to corpora lutea (conception rate) was significantly different between groups. In this first screening, with a limited number of bitches, EG-frozen semen did not show a higher fertility than G-frozen semen when used for two intravaginal inseminations. Irrespective of the semen used, conception rate was 0.50.

Semen quality and interval to sterility in tom cats treated with a 9.4 mg deslorelin implant

Objectives Gonadotropin-releasing hormone (GnRH) agonists like deslorelin are being increasingly used in tom cats for their efficacy in controlling reproductive behaviour and fertility. Deslorelin implants have been widely available in Europe since 2008. Little, if anything, is known about the interval between treatment and onset of sterility, as well as semen quality, after treatment in tom cats. The purpose of this study was to investigate semen quality and interval to sterility in tom cats treated with a 9.4 mg deslorelin implant. Methods Fifteen healthy adult tom cats were treated with a 9.4 mg deslorelin implant (Suprelorin 12). For each cat, semen collection and a GnRH stimulation test (intramuscular administration of 50 μg gonadorelin [Fertagyl], followed by blood sampling 1 h later, to assay serum testosterone) were performed on the first consultation and then repeated every 15 days until complete sterility was achieved. Semen collection was performed by introducing a 14 cm, open-end feline catheter (Argyle) 9 cm into the distal urethra 10 mins after sedation by intramuscular injection of 100 μg/kg medetomidine (Domitor). Results Semen collection was not successful in all cats at each attempt. In the first month after treatment, the semen of only four cats could be evaluated, while the semen of eight cats could be evaluated during the second and third months of the study. Semen quality (ejaculate volume, progressive motility and morphological abnormalities) improved slightly during the first 19–25 days in 2/4 cats, and in 1/4 cats motility was still very high (80%) 25 days post-treatment (PT), but we have no data regarding fertility prior to treatment in this cat. The last cat never produced spermatozoa. Subsequently, semen quality gradually worsened in all cats from 30 days onwards. At 70 days PT, one cat was still potentially fertile. After 72 days all cats were sterile. Conclusions and relevance Semen quality increased slightly in treated cats during the first month after treatment, and then gradually decreased over the following months. Complete sterility was reached within 40–72 days following implantation.

Full recovery of subinvolution of placental sites in an American Staffordshire terrier bitch

A three-year-old, sexually intact, female American Staffordshire terrier was presented with chronic postpartum vulvar haemorrhage. Sixty-one days before presentation, the bitch had whelped 10 puppies. A tentative diagnosis of subinvolution of placental sites was made when syncythial trophoblast-like cells were identified in the specimen collected through the opening of the cervix by endoscopy. Five weeks after the diagnosis, the bitch was clinically healthy with no vaginal bleeding and spontaneous recovery occurred without surgical treatment.

Effect of an injectable cabergoline formulation on serum prolactin (PRL) and milk secretion in early postpartum Beagle bitches.

This study was conducted in order to evaluate effects on prolactin (PRL) concentration and mammary milk secretion of an injectable cabergoline formulation administered to five lactating Beagle bitches during early postpartum (PP). Bitches were bled twice daily (from PP day 3 to PP day 12) and then daily (from PP day 13 to PP day 16) to assay serum PRL. On PP day 6, a subcutaneous (SC) injection of 0.1 ml/kg of placebo was administered. On PP day 9, a SC 0.1 ml/kg dose of injectable cabergoline was administered. All bitches were checked for milk production, using a clinical scoring in order to quantify milk expression from each teat. A circadian variation of serum PRL was evident during the 6 days of pre-treatment monitoring. The day after cabergoline injection, an 80% decrease of PRL serum concentration was observed (p < 0.05). The circadian oscillatory pattern of PRL secretion disappeared after administration of cabergoline, and PRL values remained significantly lower than in the previous days for the first 60 h following treatment (p < 0.001). Milk production was drastically reduced when comparing pre-treatment to post-treatment scores (p < 0.001). A single dose of injectable cabergoline caused a significant reduction in serum PRL concentration and a significant reduction in milk flow. The injectable formulation of cabergoline appeared to be safe and well tolerated.

Normal ultrasonographic reference values for the gastrointestinal tract in developing puppies

Thickness of the individual layers of the wall of the stomach, duodenum, jejunum and colon was assessed by means of ultrasonography in developing puppies at 4, 8 and 16weeks of age. Reference intervals for the thickness of individual ultrasonographic layers of the stomach, duodenum, jejunum and colon at different ages are reported. An increase in wall thickness of all the examined gastro-intestinal tracts in relation to age was recorded. The effect of body-weight was stronger on duodenal and jejunal thickness whereas it resulted lesser on stomach and colon. Correlation between duodenal and jejunal mucosal layer thickness and body weight was strong, while correlation between body weight and the other intestinal wall layers of the duodenum, jejunum and colon ranged from moderate to weak. No effects of gender were detected.

Postponement of puberty in queens treated with deslorelin

Objectives The purpose of this study was to assess efficacy of deslorelin, a gonadotropin-releasing hormone (GnRH) agonist marketed in Europe for the control of male dog reproduction, for the postponement of puberty in queens. Methods Nine prepubertal queens aged 3–9 months were selected for this study; their general and reproductive health was checked through clinical, haematological, vaginal cytology and hormonal tests. Following treatment with a 4.7 mg deslorelin implant, each cat received a monthly clinical examination and blood was collected for hormonal assay every third month. Cats were monitored for 14.1 ± 5.2 (range 7–23) months. Results All cats were in good body condition and normal health prior to treatment. Their health status remained unchanged throughout the study and no significant variation was observed with regard to serum progesterone or oestradiol. Seven days post-treatment, 1/9 queens showed signs of heat, and one other queen showed complete vaginal keratinisation. No other signs of heat were subsequently observed in any other queen. Five queens were lost during the study after 7, 7, 16, 17 and 18 months of observation (during which time they did not show signs of heat). By the end of the study, no sign of puberty was observed in the four remaining queens at 21–36 months of age. Conclusions and relevance A 4.7 mg deslorelin implant was able to suppress the feline pituitary–gonadal axis, leading to postponement of puberty for up to 21–36 months in the four queens that completed the study. Deslorelin can be considered as a safe method to postpone puberty in queens.