Intraoperative and early postoperative pain in cats that underwent ovariohysterectomy using a spay hook: a randomised, masked, experimental study.

BACKGROUND: This study aimed to compare the feasibility and practicality of the ovariohysterectomy (OHE) technique in cats with or without a spay hook with respect to the incision size, surgical time, surgical variables, and intra- and postoperative pain. Twenty-nine female cats underwent OHE using a spay hook (spay hook group [SHG], n = 15) or without using a spay hook (control group [CG], n = 14) to achieve the ovaries and cervix. Physiological parameters were monitored during the intraoperative period, and postoperative pain was assessed using a multidimensional composite and visual analogue pain scales. RESULTS: The SHG had a significantly shorter operative time than the CG. The variables in the intraoperative period showed no statistically significant difference between both groups, as well as the early postoperative pain. CONCLUSIONS: Less invasive OHE using a spay hook could potentially be a viable and feasible technique when performed by an inexperienced surgeon with appropriate training, especially in sterilisation campaigns, reducing the time to perform the procedure and increasing the number of animals spayed per time.

Durable contraception in the female domestic cat using viral-vectored delivery of a feline anti-Müllerian hormone transgene.

Eighty percent of the estimated 600 million domestic cats in the world are free-roaming. These cats typically experience suboptimal welfare and inflict high levels of predation on wildlife. Additionally, euthanasia of healthy animals in overpopulated shelters raises ethical considerations. While surgical sterilization is the mainstay of pet population control, there is a need for efficient, safe, and cost-effective permanent contraception alternatives. Herein, we report evidence that a single intramuscular treatment with an adeno-associated viral vector delivering an anti-Müllerian hormone transgene produces long-term contraception in the domestic cat. Treated females are followed for over two years, during which transgene expression, anti-transgene antibodies, and reproductive hormones are monitored. Mating behavior and reproductive success are measured during two mating studies. Here we show that ectopic expression of anti-Müllerian hormone does not impair sex steroids nor estrous cycling, but prevents breeding-induced ovulation, resulting in safe and durable contraception in the female domestic cat.

Identification of spayed and neutered cats and dogs: Veterinary training and compliance with practice guidelines.

Spay/neuter identification tattoos and ear-tipping are simple and cost-effective methods to minimize the likelihood of unnecessary anesthesia and surgery in companion animals or the misidentification of sexually intact animals. This study assessed training of sterilization identifiers in US and Canadian veterinary schools and practitioner compliance with guidelines for identifiers via surveys conducted in 2019. Faculty in all 34 schools responded to the survey, reporting that curricula included sterilization identifiers in 31% of lecture-based training, 75% of spay/neuter laboratory-based training, and 38% of clinical practice-based training. A total of 425 facilities performing spay/neuter reported frequency and technical aspects of sterilization identifiers in client-owned and unowned (shelter, rescue, trap-neuter-return) animals. Facilities encountering large numbers of animals of unknown background, performing a high number of surgeries, or with specialized spay/neuter training were significantly more likely to use identifiers. Only 5% of private practices tattooed all owned animals, and 21% tattooed all unowned animals. In contrast, 80% of shelters and 72% of spay/neuter clinics tattooed all owned animals, and 84% of shelters and 70% of spay/neuter clinics tattooed all unowned animals. Green was the most common tattoo color (97%); the most common placement was near or in the incision for female cats (99%), female dogs (99%), and male dogs (92%), and ventral abdomen in male cats (55%). Enhanced training and implementation of best practices described in professional guidelines for sterilization identifiers are needed throughout the veterinary industry to protect animals from unnecessary procedures and to prevent unintended litters in animals misidentified as previously sterilized.

Concepts in Sterilization.

The topic of surgical sterilization in companion animals is evolving. Although early spay and neuter has been advocated to prevent overpopulation of unwanted pets, recent research has focused on the timing of gonadectomy in relation to risk of various neoplasms, orthopedic conditions, and miscellaneous conditions. Many of these studies are breed-specific or draw from large veterinary medical databases, making it difficult to guide recommendations on the timing of sterilization across various breeds and mixed-breeds. This article attempts to synthesize the data and help guide decision making on the type and timing of sterilization procedures performed, including gonad sparing sterilization surgeries.

Guidance for management of free-roaming community cats: a bioeconomic analysis.

OBJECTIVES: This study used computer simulation modeling to estimate and compare costs of different free-roaming cat (FRC) management options (lethal and non-lethal removal, trap-neuter-return, combinations of these options and no action) and their ability to reduce FRC population abundance in open demographic settings. The findings provide a resource for selecting management approaches that are well matched for specific communities, goals and timelines, and they represent use of best available science to address FRC issues. METHODS: Multiple FRC management approaches were simulated at varying intensities using a stochastic individual-based model in the software package Vortex. Itemized costs were obtained from published literature and expert feedback. Metrics generated to evaluate and compare management scenarios included final population size, total cost and a cost efficiency index, which was the ratio between total cost and population size reduction. RESULTS: Simulations suggested that cost-effective reduction of FRC numbers required sufficient management intensity, regardless of management approach, and greatly improved when cat abandonment was minimized. Removal yielded the fastest initial reduction in cat abundance, but trap-neuter-return was a viable and potentially more cost-effective approach if performed at higher intensities over a sufficient duration. Of five management scenarios that reduced the final population size by approximately 45%, the three scenarios that relied exclusively on removal were considerably more expensive than the two scenarios that relied exclusively or primarily on sterilization. CONCLUSIONS AND RELEVANCE: FRCs present a challenge in many municipalities, and stakeholders representing different perspectives may promote varying and sometimes incompatible population management policies and strategies. Although scientific research is often used to identify FRC impacts, its use to identify viable, cost-effective management solutions has been inadequate. The data provided by simulating different interventions, combined with community-specific goals, priorities and ethics, provide a framework for better-informed FRC policy and management outcomes.

Effect of sterilization on the canine vaginal microbiota: a pilot study.

BACKGROUND: Surgical sterilization is the most effective method of contraception for dogs. It also prevents pyometra and reduces the risk of mammary tumour development. However, this procedure also has negative effects, such as urinary incontinence. Steroid hormone deprivation following gonadectomy could also affect canine vaginal mucosa conditions and the microbial community colonizing the vaginal tract. This hypothesis was tested by comparing the vaginal cytology and microbial community of two groups of bitches, including 11 in anoestrus and 10 sterilized bitches (post-pubertal sterilization in the last 4 years). Bacteria were identified through metataxonomic analysis, amplifying the V3-V4 regions of 16S rRNA gene, and culturing methods. RESULTS: Vaginal mucosa cytology was suggestive of dystrophic conditions in sterilized bitches, whereas a typical anoestrus pattern with parabasal and intermediate cells was appreciable in anoestrous animals. Metataxonomic analysis revealed large inter-individual variability. Salmonella, Mycoplasma and Staphylococcus were present in moderate quantities in almost all the samples in both groups. Mollicutes (class level) and Tenericutes (phylum level) were commonly present in moderate quantities in anoestrus samples, whereas these microbes were present at high levels in a single sample from the sterilized group. Based on culturing, a higher number of different species were isolated from the anoestrous bitches, and Mycoplasma canis was exclusively identified in an anoestrous bitch. Staphylococcus spp. was the most frequently isolated genus in both groups, followed by Streptococcus spp., and, among gram-negative bacteria, Escherichia spp. and Haemophilus spp. A comparison of the numbers of the most frequently isolated genera of bacteria from vaginal cultures of bitches revealed that Pasteurella and Proteus were the most frequently identified in sterilized animals based on metataxonomic analysis (p-value = 0.0497 and 0.0382, respectively), whereas Streptococcus was significantly and most frequently isolated from anoestrous bitches using culture methods (p value = 0.0436). CONCLUSIONS: In this preliminary investigation, no global patterns of the vaginal bacteria community were noted that characterized the condition of the bitches; however, cytology suggested local modifications. Sterilization after puberty caused minimal alterations in the vaginal microbial community of bitches within 4 years after surgery.

Anesthetic effects of ketamine-medetomidine-hydromorphone in dogs during high-quality, high-volume surgical sterilization program under field conditions.

OBJECTIVE: To describe the anesthetic and adverse effects of an injectable anesthetic protocol in dogs as part of a high-volume sterilization program under field conditions in Belize. STUDY DESIGN: Prospective, observational, field study. ANIMALS: A total of 23 female and eight male dogs (14.2 ± 7.7 kg; age ≥ 8 weeks). METHODS: Using a volume per kg-based dose chart, dogs were administered ketamine (4.5 mg kg-1), medetomidine (0.04 mg kg-1) and hydromorphone (0.09 mg kg-1) intramuscularly. After induction of anesthesia, an endotracheal tube was inserted and dogs were allowed spontaneous breathing in room air. Monitoring included peripheral oxygen saturation (SpO2), mean arterial pressure (MAP), heart rate (HR), respiratory rate, rectal temperature and end-tidal carbon dioxide (Pe'CO2). Meloxicam (0.2 mg kg-1) was administered subcutaneously after surgery. Data were analyzed with linear models and chi-square tests (p < 0.05). RESULTS: Onset of lateral recumbency (3.4 ± 2 minutes) was rapid. Desaturation (SpO2 < 90%) was observed at least once in 64.5% of dogs and was more frequent in large dogs (p = 0.019). Hypercapnia (Pe'CO2 ≥ 50 mmHg; 6.7 kPa) was observed in 48.4% of dogs. MAP was 111 ± 19 mmHg, mean ± standard deviation. Hypertension (MAP ≥ 120 mmHg), bradycardia (HR ≤ 60 beats minute-1) and tachycardia (HR ≥ 140 beats minute-1) were observed in 45.2%, 16.1% and 3.3% of dogs, respectively. Hypotension and hypothermia were not observed. Sex was not significantly associated with any complication. Return of swallowing reflex and time to standing were 71 ± 23 and 152 ± 50 minutes after injection, respectively. Return of swallowing was significantly longer in large dogs. CONCLUSIONS AND CLINICAL RELEVANCE: At the doses used, ketamine-medetomidine-hydromorphone was effective in dogs for high-volume sterilization. In this field setting, adverse effects included hypoventilation, hypoxemia and prolonged recovery.

Cats undergoing spay with medetomidine, ketamine and butorphanol develop arterial oxygen desaturation independent of surgical positioning and increased intraocular pressure in Trendelenburg position.

INTRODUCTION: This study observed the effects of three different surgical positions on arterial blood oxygenation measured noninvasively by pulse oximetry (SpO2) and on intraocular pressure (IOP) in anaesthetised cats undergoing spay. A total of 222 female feral cats were anaesthetised for a large-scale trap-neuter-return program with an intramuscular combination of medetomidine (0.03 - 0.05 mg/kg), ketamine (7 - 10 mg/kg) and butorphanol (0.4 mg/kg). Cats were randomly allocated to undergo spay in either Trendelenburg (70° downward head tilt), lateral or dorsal recumbency. SpO2 and pulse rate were measured at baseline, prior to surgical positioning, after one minute in surgical position and in one-minute intervals after surgical incision. Intraocular pressure was measured before positioning and at the end of surgery. At the end of surgery, all cats were placed into left lateral recumbency and all parameters were revaluated after five minutes. No significant differences between the three positions were found regarding SpO2, but an increase over time was observed. In total, 52 ± 10% (mean ± SD) of cats were hypoxaemic (SpO2 < 90%) at baseline. SpO2 improved over time, but 27 ± 3% (mean ± SD) of the cats remained hypoxaemic at the end of surgery. Trendelenburg position increased IOP during surgery (mean 31 ± 6 mmHg, individual max. 48 mmHg, versus 17 ± 4 mmHg in dorsal/lateral recumbency) but normalised after 5 mins in lateral recumbence. All cats recovered well from surgery and were released within 24 hours post-anaesthesia. Surgical position was shown to have no notable influence on SpO2 during anaesthesia in cats not receiving oxygen supplementation, whereas Trendelenburg position led to increased IOP. Oxygen supplementation is recommended with this anaesthetic protocol, as hypoxaemia is frequently observed.

INTRODUCTION: Dans cette étude, on a observé les effets de trois positions chirurgicales différentes sur l'oxygénation du sang artériel mesurée de manière non invasive par oxymétrie de pouls (SpO2) et sur la pression intraoculaire (PIO) chez des chattes anesthésiées subissant une stérilisation. Un total de 222 chattes sauvages ont été, dans le cadre d'un large programme de piégeage-castration-libération, anesthésiées avec une combinaison de médétomidine (0,03 à 0,05 mg/kg), de kétamine (7 à 10 mg/kg) et de butorphanol (0,4 mg/kg) par voie intramusculaire. Les chattes ont été réparties au hasard pour subir une stérilisation en Trendelenburg (inclinaison de la tête à 70 ° vers le bas), en décubitus latéral ou dorsal. La SpO2 et la fréquence du pouls ont été mesurées au départ, avant le positionnement chirurgical, après une minute en position chirurgicale et à des intervalles d'une minute après l'incision chirurgicale. La pression intraoculaire a été mesurée avant le positionnement et à la fin de la chirurgie. À la fin de la chirurgie, toutes les chattes ont été placées en décubitus latéral gauche et tous les paramètres ont été réévalués après cinq minutes. Aucune différence significative entre les trois positions n'a été constatée concernant la SpO2, mais une augmentation au fil du temps a été observée. Au total, 52 ± 10% (moyenne ± SD) des chattes étaient hypoxémiques (SpO2.

High-quality, high-volume spay-neuter: Access to care and the challenge to private practitioners.

IMPACT: Low-cost spay-neuter clinics were first established nearly 50 years ago in response to the numbers of dogs and cats euthanized in animal shelters. Since then, high-quality, high-volume spay-neuter (HQHVSN) clinics have been established throughout the USA and have contributed to a significant reduction in animal euthanasia in shelters. These clinics, specializing in efficient systems and surgical techniques, provide an avenue for clients who cannot afford surgery to sterilize their pets. These clinics have also helped animal shelters with limited financial resources implement spay-neuter prior to adoption policies. RESPONSE: The veterinary profession's reaction to HQHVSN clinics has been mixed; some practitioners question the quality of care provided or fear the loss of clientele, while others recognize the need for such clinics and support their development. CHALLENGES: As veterinary education has become more expensive and veterinary care more sophisticated, the cost of veterinary care, including spay-neuter surgery, has risen. With increasing costs, the numbers of pets that receive little or no veterinary care has increased. Indeed, a 2018 survey by the Access to Veterinary Care Coalition documented that more than 25% of pet-owning households in the USA experienced difficulties obtaining veterinary care for their pets and the most frequent barrier was financial. AIM: This review looks at the reality of HQHVSN clinics and what this means for the private practitioner. By adopting similar systems and techniques that lower the cost of spay-neuter surgery, practitioners could potentially pass on cost savings to clients. Moreover, the same principles may be applied to other aspects of basic care to further address access to care issues.

Uterine secretory activity and histology of prepubertal female dogs in an animal model of partial ablation of endometrial glands development / Atividade secretória uterina e histologia de cadelas pré-púberes em um modelo animal de ablação parcial do desenvolvimento das glândulas uterinas

Inadequate exposure of the female reproductive system to steroids in uterine developmental periods can partially inhibit the development of endometrial glands in dogs. However, the effects of steroids on the formed glands functionality remain unknown, as well as the possible occurrence of endometrial fibrosis. This study aimed to evaluate the secretory activity of endometrial glands in prebubertal female dogs submitted to a protocol of partial ablation of the uterine adenogenesis. Sixteen females of non-specific breed were distributed into two groups; MPA (n=8), females that received applications of medroxyprogesterone acetate every 3 weeks; and C (n=8) untreated control females. Ovariohysterectomy was performed in all animals at the age of 6 months and evaluated the uterine horns by histological and histochemistry exams. The secretion intensity (degrees 1-4) was evaluated using periodic acid-Schiff (PAS) and alcian blue (AB) pH 2.5. Histological evaluation was performed using Masson's trichrome and toluidine blue. Only degree 1 and 2 marks for PAS were observed in both groups, with no difference of uterine secretion intensity between the groups regarding the degrees found. However, the MPA group revealed higher intensity of uterine secretion compared to group C (p<0.05). Staining with AB pH 2.5 also revealed only degree 1 and 2 marks in both groups, with no statistically significance between them. Masson's trichrome staining revealed no marks in the periglandular region in both groups. A higher among of mast cells was observed in the myometrial region of the uterus in both groups. Prepubertal female dogs with partial ablation of the uterine adenogenesis present minimal uterine secretory activity, absence of periglandular fibrosis and increased presence of mast cells in the myometrium compared to endometrium.(AU)

A exposição inadequada do sistema reprodutor feminino a esteróides em períodos do desenvolvimento uterino pode inibir parcialmente o desenvolvimento das glândulas endometriais em cães. Entretanto, não se conhece os efeitos dos esteróides sobre a funcionalidade das glândulas formadas, bem como a possível ocorrência de fibrose endometrial. Objetivou-se avaliar a atividade secretória das glândulas endometriais de cadelas pré-púberes submetidas a protocolo de ablação parcial da adenogênese uterina. Foram utilizadas 16 fêmeas, sem-raça-definida, distribuídas nos grupos MPA (n=8), fêmeas que receberam aplicações de acetato de medroxiprogesterona a cada 3 semanas, e C (n=8), fêmeas controle não tratadas. Aos seis meses de idade, foi realizada ovariohisterectomia em todos os animais, e avaliados os cornos uterinos pelo exame histológico e de histoquímica. Para avaliar a intensidade de secreção (graus 1-4), foram utilizadas periodic acid-Schiff e alcian blue (AB) pH 2,5. Para a avaliação histológica foram utilizados tricrômico de Masson e azul de toluidina. Apenas marcações graus 1 e 2 foram observadas para PAS em ambos os grupos, sem diferença na intensidade de secreção uterina entre grupos com relação aos graus encontrados. Entretanto, o grupo MPA apresentou maior intensidade de secreção uterina em relação ao grupo C (p<0,05). Com relação ao AB pH 2,5, em ambos os grupos também foram encontradas apenas marcações de graus 1 e 2, sem diferença estatística entre grupos. Não foram observadas marcações para a coloração de tricrômico de Masson na região periglandular, em ambos os grupos. Foi observada maior quantidade de mastócitos presentes no útero na região do miométrio, em ambos os grupos. Conclui-se que cadelas pré-púberes com ablação parcial da adenogênese uterina apresentam mínima atividade secretória uterina, ausência de fibrose periglandular e maior presença de mastócitos no miométrio em relação ao endométrio.(AU)

Mechanistic insight into the role of immunocastration on eliminating skatole in boars.

The accumulation of skatole in fat tissue is one of the predominant factors, causing boar taint. The present study was aimed to understand the mechanism whereby active immunization against GnRH (immunocastration) eliminates skatole in boars. Thirty-six boars were assigned within litter into three groups (n = 12): control, surgically castrated, or immunized against GnRH at 10 wk of age (with a booster 8 wk later). Faecal and blood samples (for skatole and skatole-regulatory hormone profiles) were collected at 4-wk intervals until boars were slaughtered (26 weeks). Immunocastration reduced (P < 0.05) serum levels of androstenone, 17ß-estradiol and IGF1 especially after the booster immunization, and down-regulated (P < 0.05) mRNA expressions of both IGF1 and IGF1receptor (IGF1R) in mucosa of ileum as well as colon at slaughter. Compared to intact controls, immunocastration substantially decreased (P < 0.05) faecal skatole contents subsequent to the decrease of serum IGF1 levels, which persisted in boars after surgical castration. In parallel with the decreased formation of skatole in the intestine, levels of skatole in serum and then in fat tissue were also decreased (P < 0.05). On the other hand, deprivation of testicular steroids, especially androstenone and 17ß-estradiol accelerated skatole degradation metabolism in the liver by increasing (P < 0.05) hepatic CYP2E1, CYP2A, CYP2C49 and CYB5A expressions. Collectively, our results suggested that immunocastration decreased skatole formation in the intestine and meanwhile accelerated skatole degradation metabolism in the liver, resultantly eliminating skatole accumulation in male pigs. Decreased intestinal skatole formation by immunocastration appeared to be associated with the attenuated actions of IGF1 on the turnover of both ileal and colon mucosa.

Surgical sterilization of male and female grey squirrels (Sciurus carolinensis) of an urban population introduced in Italy.

We report a successful surgical sterilization procedure for population control of 324 male and female free-ranging grey squirrels (Sciurus carolinensis) in Genoa (Italy). We describe the clinical procedure from the trapping of the animals to their surgical sterilization and release in another part of the city. Live-trapped squirrels were transported to the veterinary clinic within 1-2 hr of capture and maintained in a hospitalization room reserved for them. The waiting period before surgery was kept below 12 hr. The developed procedure has resulted in a survival of 94% of trapped squirrels from surgery to animal release. Sterilized squirrels started to feed in a very short time (1.0-1.5 hr), and after 2-3 days, it was possible to release them in a new area. Amoxicillin was used as a long-acting postoperative antibiotic to reduce the period of captivity. The successful surgical procedure described here can provide an important additional tool for the management of introduced populations of squirrels. We showed that the surgical sterilization of some hundred squirrels is clinically possible and could be included in management strategies aimed at removing critical populations of these species. Moreover, the data allow dosages and operational times in order to provide economic viability assessment of future population control measures.

Effects of intratesticular vs intraepididymal calcium chloride sterilant on testicular morphology and fertility in dogs.

BACKGROUND: Both stray and free-roaming owned dogs contribute to the serious global dog overpopulation problem. Many dog owners are unwilling to have their pet castrated for various reasons, including a reluctance to have their dog's behavior changed. A non-surgical method of sterilizing both stray and owned dogs would help to prevent unwanted litters. Previous studies have shown that intratesticular injection of calcium chloride dihydrate (CaCl2) in alcohol is a promising and cost-effective alternative to surgery for stray dogs, with testosterone significantly decreased and sexual activity eliminated. The aim of this study was to compare the use of a solution of 20% CaCl2 in 95% ethanol injected into the testicles or into the head of the epididymis. METHODS: A total of 148 dogs divided into 4 groups (2 experimental and 2 control) were respectively injected with CaCl2 or saline solution into the testicle or epididymal head (ultrasound-guided). The animals were examined at 0, 3, 6, and 9 months for sperm quality, concentration of testosterone in serum, and side effects; at 0 and 5 months with contrast-enhanced ultrasound (CEUS) to enhance the morphological aspects/alteration of the testicular parenchyma or epididymis; and at 9 months when all were castrated for histological examination. RESULTS: All dogs treated with CaCl2 became sterile with azoospermia achieved over the 9-month study. The concentration of testosterone in serum significantly decreased following intratesticular treatment with CaCl2. No adverse effects were noted. CONCLUSIONS: A single, bilateral intratesticular injection of 20% CaCl2 in 95% ethanol was confirmed to be a reliable method for induction of sterilization in male dogs. The approach showed long-term efficacy and may reduce sexual behavior, with the additional benefits of low-cost and ease of use, making this nonsurgical method appropriate for use in stray dogs. Sterility was also achieved if injected in the head of the epididymis but no significant decrease in serum concentration of testosterone occurred. Moreover, performing the intraepididymal injection into the epididymal head was as time consuming as orchiectomy. This approach may be optimal for use in owned dogs where anatomical integrity and testosterone maintenance is preferred by the owner.

Owner satisfaction with use of videoconferencing for recheck examinations following routine surgical sterilization in dogs.

OBJECTIVE To evaluate owner satisfaction with a home-based, synchronous videoconferencing telemedicine application as an alternative to in-clinic appointments for conducting recheck examinations after surgical sterilization in dogs. DESIGN Randomized controlled clinical trial. ANIMALS 30 client-owned dogs undergoing elective surgical sterilization and postsurgical recheck examination between September 27, 2017, and February 23, 2018. PROCEDURES Dogs were randomly assigned to have their recheck examinations performed remotely (the telemedicine group) or at the veterinary clinic (the control group). After the recheck examination, owners completed a survey regarding their satisfaction with the recheck examination and their dogs' behavior during it. Information regarding the surgery and recheck examination was obtained from the electronic medical record. Mann-Whitney U tests were used to compare results between the telemedicine and control groups. RESULTS Owners were equally satisfied with recheck examinations performed by videoconference and in-clinic appointments. Owners of dogs in the telemedicine group indicated that their dogs were less afraid during the virtual appointment, compared with what was typical for them during in-clinic appointments, but the difference was not statistically significant. Most owners who completed a postsurgical recheck examination by videoconferencing preferred this method for similar appointments in the future. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that owners were satisfied with videoconferencing as a means of conducting a postsurgical recheck examination. Further research is needed to assess videoconferencing's ability to reduce signs of fear in dogs during veterinary examinations, its economic feasibility, and the willingness of veterinarians and animal owners to adopt the technology.

Calcium chloride combined with dimethyl sulphoxide for the chemical sterilization of dogs.

The aim of this study was to evaluate the effect of intratesticular injection of calcium chloride (CaCl2 ) combined with dimethyl sulphoxide (DMSO) as a chemical sterilization in dogs. Twelve dogs were divided into two groups: the treated group (n = 6), in which 15 mg/kg of a 7.5% CaCl2 solution combined with 0.5% DMSO was injected into each testicle (volume range 1.0-4.76 ml); and a control group (n = 6) that received the same volume/kg of 0.9% sodium chloride solution (NaCl). Semen characteristics pre- and post-treatment were evaluated. Serum testosterone concentration was determined before the injection (D-1) and at 15 (D15), 30 (D30) and 60 (D60) days after intratesticular injection. Testicle sizes and local pain were evaluated for 7 consecutive days (D1 to D7) and at D15, D30 and D60 after injection. At D60, testicle histological evaluation was performed after orchiectomy. No pain was observed by testicular palpation, with the exception of one dog in the treated group; this dog then received analgesic therapy. An increase in testicular volume was evident within 24 hr after treatment, followed by gradual reduction for 3 weeks. Five of 6 dogs from the treated group presented azoospermia at D15; the remaining dog presented at D30. There was no significant difference in testosterone concentrations in the treated group during the experimental period. Histological evaluation showed testicular degenerative lesions, especially at the proximal and middle portions. The results indicated that one injection of 7.5% CaCl2 combined with 0.5% DMSO into each testis is a viable alternative for canine sterilization.

Vigilancia, prevención y control de la rabia: Ciudad de Buenos Aires: Junio 2018 / Surveillance, prevention and control of rabies: City of Buenos Aires: June 2018

La rabia es una enfermedad viral, de distribución mundial que afecta al hombre y a todos los mamíferos tanto domésticos como silvestres, con una letalidad del 100% afectando el sistema nervioso central. Se transmite por medio de la inoculación del virus contenido en la saliva del animal infectado, principalmente por mordeduras o el lamido de heridas, o por predación cuando un animal caza un murciélago infectado y toma contacto con el virus desde el encéfalo del quiróptero. Otras formas de transmisión, menos frecuentes son por trasplante de tejidos infectados o por aerosoles. En este apartado, se describe la situación epidemiológica de esta zoonosis en la Ciudad de Buenos Aires: observación de animales mordedores, detección de virus rábico en muestras mediante diagnóstico de laboratorio, vacunación de animales y control poblacional mediante esterilizaciones quirúrgicas, acciones de control de focos de rabia, y seguimiento de animales con exposición a murciélagos positivos a rabia o no analizables

Breed prevalence of canine lymphoma in South Africa.

Lymphoma is a common haematopoietic neoplasm in dogs. Several breeds have been shown to have a predisposition to lymphoma; however, very little information exists regarding the South African dog population. This study assessed whether any breed had increased odds of developing lymphoma compared with others, and also investigated the effects of age, sex and neutering status on disease prevalence. Two study populations and their corresponding reference populations were studied retrospectively. Odds ratios (ORs) for lymphoma in 49 dog breeds, together with their 95% confidence intervals (CI), were calculated. Age effect was assessed by calculating ORs for different age categories in one of the populations. The chi-square test was used to evaluate differences in the prevalence of the various sex and neutering categories in one lymphoma population compared with its reference population. Fourteen breeds had significantly increased odds of developing lymphoma, and one breed had significantly decreased odds (p < 0.050). The median ages of the two lymphoma populations were 6.5 and 8.0 years, with the 6.1-9.0 year category having significantly increased odds of developing lymphoma (OR 1.61, CI 1.2-2.16, p = 0.002). In one of the lymphoma populations, higher proportions of males (p = 0.033) and neutered females (p = 0.006) were found when compared with the reference population. These findings suggest that certain breeds in South Africa have a higher risk of developing lymphoma, and that sex hormones may play a role in lymphoma pathogenesis. The findings may provide useful information for pet owners and veterinarians.

Population Control in Small Animals.

Optimal age for ovariohysterectomy or castration has not been defined in the scientific literature. Bitches and queens are significantly less likely to develop mammary neoplasia, which has a high incidence and potentially high morbidity and mortality, if spayed when young. Tom cats exhibit undesirable behaviors that preclude them being good pets and should be castrated young. There is no compelling reason to castrate male dogs when young unless it is needed to control reproductive behaviors or prevent indiscriminate breeding. Alternatives to surgical sterilization that may be available in the future include intratesticular injection and immunization against gonadotropin-releasing hormone.

Laparoscopic ovariectomy in eastern grey kangaroos (Macropus giganteus) and red kangaroos (Macropus rufus).

OBJECTIVE: To develop a technique for permanent sterilisation of female eastern grey kangaroos (Macropus giganteus) and red kangaroos (M. rufus) as part of a large-scale macropod management program on an enclosed 1545-ha site in western Sydney. METHODS: Free-ranging female kangaroos (n = 1409: 1285 eastern grey kangaroos, 124 red kangaroos) were anaesthetised via remote anaesthetic drug delivery of tiletamine/zolazepam, medetomidine and acepromazine prior to inhalational anaesthesia using isoflurane-oxygen. A laparoscopic ovariectomy technique was developed using standard laparoscopic equipment to effect permanent sterilisation of the kangaroos. The technique described was also adapted for use on immature animals weighing as little as 1 kg. No direct post-surgical care was provided once the animals had recovered from the anaesthetic. RESULTS: The procedure was simple to perform and had a very high success rate, with an overall project mortality rate of 2.13% (n = 30). Seven kangaroos (0.05% of all operated kangaroos) were euthanased as a direct result of the surgical procedure. Surgical complications were rare but included inadvertent gastrointestinal tract puncture with the trocar, intraoperative haemorrhage and subcutaneous emphysema leading to pouch eversion following surgery. CONCLUSION: The procedure described is a rapid and effective method of permanent fertility control in macropods and carries a low mortality rate.

Triploid or hybrid tetra: Which is the ideal sterile host for surrogate technology?

This work was aimed at developing an effective procedure to obtain sterile ideal host fish in mass scale with no endogenous germ cells in the germinal epithelium, owning permanent stem-cell niches able to be colonized by transplanted germ cells in surrogate technology experiments. Thus, triploids, diploid hybrids, and triploid hybrids were produced. To obtain hybrid offspring, oocytes from a single Astyanax altiparanae female were inseminated by sperm from five males (A. altiparanae, A. fasciatus, A. schubarti, Hyphessobrycon anisitsi, and Oligosarcus pintoi). Triploidization was conducted by inhibition of the second polar body release using heat shock treatment at 40 °C for 2 min. At 9-months of age, the offspring from each crossing was histologically evaluated to access the gonadal status of the fish. Variable morphological characteristics of the gonads were found in the different hybrids offspring: normal gametogenesis, gametogenesis without production of gametes, sterile specimens holding germ cells, and sterile specimens without germ cells, which were considered "ideal hosts". However, only in the hybrid derived from crossing between A. altiparanae and A. fasciatus, 100% of the individuals were completely sterile. Among them 83.3% of the male did not present germ cells inside germinal epithelium, having only somatic cells in the gonad. The other 16.7% also presented spermatogonia inside the niches. Such a methodology allows the production of sterile host in mass scale, opening new insights for application of surrogate technologies.