Atipamezole Reverses Cardiovascular Changes Induced by High-Dose Medetomidine in Cats Undergoing Sedation for Semen Collection.

This study aimed at describing the change in echocardiographic variables after high-dose medetomidine and the reversal with atipamezole in six cats undergoing sedation for semen collection. Further cardiac Troponin I (cTnI) concentration and the effect of repeated sedation were assessed. Echocardiography was performed before and 20 min after sedation with 0.1 mg/kg medetomidine intramuscularly (IM) for urethral catheterisation. Prior to epididymectomy, S-ketamine was administered intravenously. Twenty minutes after reversal with 0.5 mg/kg atipamezole IM, the third echocardiography was performed. Sedation with medetomidine and reversal with atipamezole was repeated on day 7, 14, 21 and 28. Heart rate (HR) and rhythm were monitored throughout all sedations. On day 0 and 28 cTnI concentrations were measured before and after the procedure. After normality testing, the values were compared over time. The administration of medetomidine led to a marked reduction in HR, cardiac output and ventricular systolic function and a significant increase in left ventricular dimensions. Rhythm abnormalities, such as ventricular premature complexes and idioventricular rhythm, could be observed. The administration of atipamezole completely reversed sedation and the changes in haemodynamic variables. No significant increase in cTnI concentrations could be detected, although two out of six cats showed values above the reference range.

Prevalence of lactational oestrus in cats and consequences for kittens.

OBJECTIVES: Although lactation and suckling suppresses fertility in most mammals, some feline breeders have reported spontaneous oestrus during lactation, causing distress to kittens. This led the Official French Feline Pedigree Registry (Livre Officiel des Origines Félines - LOOF) to send a questionnaire to cat breeders requesting data on their last three litters. The aim of this study was to investigate the prevalence of lactational oestrus, its impact on litters and potential associations with litter size, age, parity, breed and seasonality. METHODS: Answers from 108 breeders were collected, providing data on 238 litters in 23 different breeds. Data were also collected on successive litters from multiparous queens (n = 20) and were analysed separately from the 195 independent births. RESULTS: Of the 195 independent births with complete data sets, 96 (49%) queens came into oestrus during lactation, 37 (38%) of which were associated with loss of maternal interest (n = 20), milk quality variation (n = 2), clotted milk (n = 3), reduced milk quantity (n = 13), which in kittens led to reduced weight (n = 6), diarrhoea (n = 9), vomiting (n = 4), nausea (n = 2) or death (n = 4), and bottle feeding (n = 2), early weaning (n = 4) or modified litter behaviour (n = 1). A significant association was found between small litter size (one or two kittens) and the onset of lactational oestrus (P = 0.007) and between births occurring in February, March and April and lactational oestrus (P = 0.005); there was no association with age or breed. CONCLUSIONS AND RELEVANCE: Breeders perceived a relationship in 38% of cases of lactational oestrus with maternal disinterest, clotted milk, reduced milk yield and in kittens, weight loss, vomiting, diarrhoea or even death. An association between small litter size and lactational oestrus was found, as well as with births occurring between February and April. Breeders presenting with at-risk females should be warned. Conservative and preventive measures such as contraceptive options are discussed as a possible therapy.

Epididymectomy as a novel surgical procedure; application in the domestic cat.

Feline overpopulation raises issues concerning health, ecology, economy, and ethics. Procedures to limit overpopulation should carefully address animal welfare, efficiency, costs, and feasibility. Vasectomy in unowned cats is suggested as preferable to standard neutering as it maintains male sexual behaviour which may induce ovulation and pseudopregnancy in intact females and may prevent immigration of other males. Vasectomy is not performed routinely because it is fastidious, time consuming and requires more material than standard neutering. We describe epididymectomy as an alternative. In a first experiment, we analysed semen, testosterone, behaviour and pain in six experimental cats before and after epididymectomy, and after castration two months later. Excised tissues were analysed histologically. Testosterone concentrations did not differ significantly between intact and epididymectomised animals but were significantly different after castration. Sexual behaviour and testicular spermatogenesis persisted after epididymectomy, but with a marked drop in the semen count after 7 days. The Glasgow pain scores did not differ significantly after epididymectomy and castration. In a subsequent experiment, 20 privately owned cats were epididymectomised and castrated immediately afterwards, to analyse the learning curve and perioperative complications. The time required for an epididymectomy was significantly shorter than for castration. The study confirms that epididymectomy is quicker and less invasive than castration, it is associated with minimal risks and post-operative pain while easy to learn and inexpensive. Further field studies are required to test its efficiency for feline feral population control or in other species such as in bears, lions or deer, where infertility is required and castration not wanted.

Verifying the placement and length of feeding tubes in canine and feline neonates.

BACKGROUND: Tube feeding is a common procedure in neonatology. In humans, tube misplacement reportedly occurs in up to 59% of all cases and may lead to perforation in 1.1% of preterm intubated neonates. While numerous studies on optimal tube placement have been performed in human neonates, current recommendations on tube feeding in canine and feline neonatology are based, at best, on studies performed in adult animals. Herein, we aimed to test ultrasonography as a tool to verify tube placement in puppies and kittens and to compare different anatomical predictive markers used in human, canine and feline neonates. RESULTS: The predictive tube length when held bent between the last rib and the mouth may induce trauma compared to when held straight. A strong positive linear correlation was observed between birthweight and gastric cardia localization. Ultrasonography findings were similar to coeliotomy findings. Stomach volume was less than 2 mL per 100 g in the less-than-one-day-old studied puppies (n = 25) and kittens (n = 28). CONCLUSIONS: A weight-based equation was calculated to help predict appropriate tube placement. Ultrasonography can be used to control gastric tube placement, and neonates less than one-day-old have a smaller stomach capacity. Further studies are required to evaluate whether more-than-one-day-old puppies follow the same linear correlation with their weight. Further in vivo studies are warranted to determine the gold standard procedure for tube feeding in neonatal puppies and kittens.

Contraceptive implants used by cat breeders in France: a study of 140 purebred cats.

OBJECTIVES: Deslorelin 4.7 mg and melatonin 18 mg subcutaneous implants were studied in purebred male and female cats, via questionnaires sent to French cat breeders, to assess breed, age, duration of the contraceptive effect, fertility after use, changes in behaviour and side effects. METHODS: Reproductive data were collected in 57 tom cats and 41 queens implanted with deslorelin 4.7 mg, and 42 queens implanted with melatonin 18 mg, for a total of 140 purebred cats, from 38 different catteries, representing 18 breeds. RESULTS: Using deslorelin (Suprelorin 4.7 mg; Virbac), sexual behaviour in males was inhibited for a mean ± SD of 13.4 ± 3.2 (range 8-21) months in 37/57 cats. Of these, 24/37 mated successfully and produced litters at a mean of 15.5 ± 3.6 (range 9-20) months. Inhibition lasted 11 ± 1.1 (range 9-12; n = 6), 13.2 ± 2.4 (range 12-18; n = 6) and 15 ± 3.5 (range 9-18; n = 6) months in Norwegian Forest Cat, Singapura and Ragdoll males, respectively. In 26/41 females implanted with deslorelin 4.7 mg, oestrus was inhibited for a mean of 16.0 ± 5.7 (8-38) months; 12/26 went on to produce a litter. Of the side effects specific to females: two presented persistent oestrus, leading to the removal of the implant; two developed lactation; one had fibroadenomatosis; and one was sterilised owing to cystic endometrial hyperplasia. Using melatonin (Melovine 18 mg; Ceva), 33/42 females had oestrus inhibited for a mean of 86 ± 50 (range 21-277) days after implantation with a peak return to oestrus in March, and 12/33 had a subsequent litter. No side effects were reported. CONCLUSIONS AND RELEVANCE: This study is the first to collect a large amount of field data, in 140 purebred male and female cats where a deslorelin 4.7 mg or a melatonin 18 mg implant was used. These field results may allow for more accurate clinical advice and open up new avenues of research.

Neonatal puppy survival after planned caesarean section in the bitch using aglepristone as a primer: A retrospective study on 74 cases.

Since most of dystocia end up in caesarean sections (C-sections), the history of any problem during whelping is a good reason to plan in advance a further C-section. Our aim was to confirm that on a large sample and over an extended period of time, mortality in puppies <2 weeks of age was low, born after a planned C-section using aglepristone as a primer. Seventy-four C-sections on 59 different bitches were included. Bitches were monitored during oestrus to estimate the day of ovulation by progesterone assays; 60, 61 or 62 days after ovulation, foetal viability was checked by ultrasonography and progesterone plasma level was measured. None of the bitches was at term (progesterone plasma level >2 ng/ml). An injection of aglepristone was performed in late afternoon to block the effect of progesterone, mimicking its drop at the end of pregnancy. The C-section was conducted the following morning. Twenty-one breeds were represented most of which were bulldogs (26%, 21/74) and Great Danes (16%, 13/74). Four hundred and thirty-five puppies were born. A total of 43/435 puppies died within the first 2 weeks (9.89%). None of the puppies showed any external signs of prematurity. The average number of deaths per litter relative to the date after ovulation was similar (0.5 pups per litter at day 60, 0.7 at day 61, 0.4 at day 62). This study shows that planned C-section after an accurate determination of ovulation and using aglepristone as a primer is a safe procedure for bitches and their offspring. It may be offered to owners if a pregnant bitch is "at risk" of dystocia.

Is electroejaculation a safe procedure in cats? An endoscopic and histological prospective blinded study.

Transrectal electrostimulation is a technique used for semen collection in several animals including felids, but also in humans with spinal cord injuries and in specific cases of anejaculation. To the authors' knowledge, safety and innocuity on rectal mucosa has not yet been assessed histologically. A prospective study was performed on 10 European cats in order to determine the impact of electroejaculation on the rectal mucosa, by performing endoscopic and histological evaluation of the rectal mucosa. Endoscopic evaluation was performed before and after semen collection. Standardized biopsy specimens were collected immediately after semen collection, on the site of electrostimulation and on the proximal part of the descending colon as a control, for further double-blinded histopathological evaluation. The degree of inflammation was evaluated following the criteria from the WSAVA Gastrointestinal Standardization Group. Semen collection by electrostimulation did not induce significant histological and endoscopic lesions. Electrostimulation may therefore be considered as a safe technique to collect semen in cats.