The impact of time of neutering on weight gain and energy intake in female kittens

Identifying the target population and preventive strategies to combat feline obesity

Feline obesity continues to be a priority health and welfare issue. Most research surrounding obesity currently focuses on obesity treatment. However, treatment for feline obesity is slow, often unsuccessful and not without consequences. Identifying high-risk populations for obesity onset is crucial for developing and implementing preventive strategies. This review identifies post-gonadectomy kittens aged 5-12 months as the primary target population for obesity prevention in domestic cats and highlights dietary and feeding management strategies to be implemented for obesity prevention.

Environmental risk factors in puppies and kittens for developing chronic disorders in adulthood: A call for research on developmental programming

Many dogs and cats are affected by chronic diseases that significantly impact their health and welfare and relationships with humans. Some of these diseases can be challenging to treat, and a better understanding of early-life risk factors for diseases occurring in adulthood is key to improving preventive veterinary care and husbandry practices. This article reviews early-life risk factors for obesity and chronic enteropathy, and for chronic behavioral problems, which can also be intractable with life-changing consequences. Aspects of early life in puppies and kittens that can impact the risk of adult disorders include maternal nutrition, establishment of the gut microbiome, maternal behavior, weaning, nutrition during growth, growth rate, socialization with conspecifics and humans, rehoming and neutering. Despite evidence in some species that the disorders reviewed here reflect the developmental origins of health and disease (DOHaD), developmental programming has rarely been studied in dogs and cats. Priorities and strategies to increase knowledge of early-life risk factors and DOHaD in dogs and cats are discussed. Critical windows of development are proposed: preconception, gestation, the suckling period, early growth pre-neutering or pre-puberty, and growth post-neutering or post-puberty to adult size, the durations of which depend upon species and breed. Challenges to DOHaD research in these species include a large number of breeds with wide genetic and phenotypic variability, and the existence of many mixed-breed individuals. Moreover, difficulties in conducting prospective lifelong cohort studies are exacerbated by discontinuity in pet husbandry between breeders and subsequent owners, and by the dispersed nature of pet ownership.

Effects of a high-protein, high-fiber diet rich in antioxidants and L-carnitine on body weight, body composition, metabolic status, and physical activity levels of cats after spay surgery

Spay and neuter surgeries are useful in controlling pet populations, but increase obesity risk due to increased appetite, decreased metabolic rate and decreased energy expenditure. Dietary management may help limit post-spay weight gain, but few research studies have been conducted in cats. Therefore, the objective of this study was to evaluate the effects of a high-protein, high-fiber diet (HPHF) compared to a moderate-protein, moderate-fiber diet (MPMF) in female cats following spay surgery. Twenty healthy female cats (9.5±0.1 mo) were used. After a 4-wk baseline phase with cats fed MPMF to maintain body weight (BW), 16 cats were spayed and allotted to MPMF (n=8) or HPHF (n=8), with the remaining cats being sham-operated and fed MPMF (n=4). Cats were fed to maintain BW for 12 wk, then allowed to eat up to twice that amount for another 12 wk. Daily food intake, twice weekly BW and twice weekly body condition scores (BCS) were assessed. Back fat thickness (BF) using ultrasound, body composition using dual-energy X-ray absorptiometry (DEXA), feline body mass index (fBMI), body fat percentage estimates using zoometry measurements, serum metabolites, and voluntary physical activity levels were measured prior to spay (wk 0) and every 6 wk post-spay. A treatment*time effect was observed for food intake (g/d), but not caloric intake (kcal ME/d). Caloric intake was affected by time and treatment, being reduced over the first 12 wk and reduced at higher amounts in HPHF and MPMF cats vs. sham cats. BW, BCS and body fat percentage were affected over time. Treatment*time effects were observed for blood urea nitrogen, alkaline phosphatase, and fructosamine, while blood triglycerides, total cholesterol, creatinine, total protein, phosphorus, and bicarbonate were affected by time. Physical activity was reduced over time. Our results demonstrate that spay surgery affects food intake, BW, metabolism, and physical activity of cats. Dietary intervention in this study, however, led to minor changes.

Metabolic milieu and localization of ovarian leptin and receptor in queens under different reproduction phases

Metabolic profile and leptin presence and expression of receptor in the ovary of 8 queens were analyzed. All queens were assessed for nutritional state and underwent ovariectomy in accordance with Italian law for the control of stray cats and dogs. Three queens were at early gestation, three prepubescent and two non-pregnant. All animals appeared healthy but underweight. Haemogram and biochemical profile did not show to be of prognostic value. On microscopy, granulosa cells of secondary follicles tested positive to leptin in pregnant queens, while testing negative in non-pregnant ones. Muscular layer of vessels of the ovary in non-pregnant queens tested positive to receptor, but negative in those found pregnant. Results suggest that leptin is produced and receptor expressed in the different tissues of the ovary in underweight queens. Additionally, the expression of receptor did not necessarily imply local leptin production and clearly displayed to vary according to the reproduction phase. Taken altogether, these findings allow to conclude that the expression of receptor can be interpreted as the pillar bridging ovary tissues as target sites of circulating leptin produced elsewhere. Arguably, ovary removal may affect hormonal cross-talk at the systemic level, likely affecting different systemic functions, including the nutritional status.

Energy Requirements for Growth in the Norfolk Terrier

An appropriate energy intake for healthy growth can reduce the risk of obesity and co-morbidities, such as orthopaedic diseases. The 2006 National Research Council (NRC) universal equation calculates the energy requirement of growing dogs based on predicted adult body weight, but evidence suggests a revision may be required. This study investigates the energy requirements of seventeen Norfolk terrier puppies over their first year (10 to 52 weeks). Puppies were individually fed complete and balanced diets in amounts to maintain an optimal body condition score (BCS), recording intake daily and body weight and BCS weekly. To monitor health a veterinary examination, haematology and plasma biochemistry and serum measures of bone turnover were undertaken every 12 weeks. Skeletal development was assessed using dual-energy X-ray absorptiometry (26 and 52 weeks). Puppies were clinically healthy with normal skeletal development and healthy growth throughout. The energy intake to achieve this was significantly lower than that predicted by the NRC (2006) equation at all time points, with largest mean difference of 285 kJ/kg^0.75 per day at 10 weeks. If fed according to the NRC 2006 equation, dogs would have been in positive energy balance, possibly leading to obesity. These data support a revision to the NRC (2006) equation.

Contrasting practices and opinions of UK-based veterinary surgeons around neutering cats at four months old

BACKGROUND

Many cats in the UK are not neutered before reaching potential breeding age. The purpose of this investigation was to understand the prevalence of veterinarians' behaviours around neutering cats at four months of age and to identify any needs of the veterinary profession on this.

METHODS

A sample of 483 veterinarians that completed a cross-sectional online questionnaire were included in quantitative and qualitative analyses.

RESULTS

Almost 70 per cent of veterinarians indicated they were comfortable carrying out neutering on cats of four months of age, and approximately half of veterinarians indicated they would recommend neutering client-owned cats at four months of age if practice policy permitted. There was no association found between these practices and geographic risk factors. Instead, neutering at four months was associated with the gender of the veterinarian, their practice policy and whether they routinely neuter unowned cats. Veterinarians have contrasting beliefs on similar themes, depending on whether they neuter kittens at four months or not, including differing opinions on general anaesthetic, surgery risks, owner compliance and their perceptions of neutering practices within the wider profession.

CONCLUSION

Familiarity and experience with the procedure, alongside perceived norms, are central to beliefs. We also highlight informational and learning barriers.

Validation of saliva and urine use and sampling time on the doubly labelled water method to measure energy expenditure, body composition and water turnover in male and female cats

Less invasive protocols are necessary to study energy expenditure (EE) of cats living in homes for expressing their normal living conditions. The present study compared sampling times and the use of saliva, urine and blood to measure 2H and 18O to apply the doubly labelled water method. In the first study, four cats were used to evaluate the enrichment (2, 4, 6, 7 and 8 h) and elimination (2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 d) of 2H and 18O (subcutaneously injected). The maximum enrichment was after 5 h (R2 0·82) of injection, with an Ln linear elimination of both isotopes (P < 0·001; R2 0·99). The results of EE were similar, regardless of the sampling time used (P = 0·999). In the second study, seven male cats and seven female cats were used. Before and after isotope injection (5 h, 7 d, 10 d and 14 d), blood, saliva and urine were collected. Isotope enrichment was lower in urine (P < 0·05) and at the similar level in blood and saliva. Isotope elimination was similar for all fluids (P < 0·473). The EE calculated with blood and saliva was similar but higher for urine (P = 0·015). According to Bland-Altman statistics, blood and saliva presented low bias and high correlation (P < 0·001), but this was not observed for urine (P = 0·096). Higher EE was observed for male cats (384 (se 39) kJ/kg0·67 per d) than for female cats (337 (se 34) kJ/kg0·67 per d; P < 0·05). The sampling time for the method is flexible, and saliva can be used as a substitute for blood.

Neutering in dogs and cats: current scientific evidence and importance of adequate nutritional management

Neutering or spaying is a commonly recommended veterinary procedure. However, veterinarians are often confronted with conflicting findings and differences in concepts regarding practice and proper nutritional management after the procedure. The objective of the present review was to bring to light the most recent literature, summarise it and discuss the findings focusing on the risks and benefits of neutering in dogs and cats, and to determine the appropriate nutritional management for these animals.

PANCOSMA COMPARATIVE GUT PHYSIOLOGY SYMPOSIUM: ALL ABOUT APPETITE REGULATION: Effects of diet and gonadal steroids on appetite regulation and food intake of companion animals

The prominent incidence of overweight and obese pet animals not only results in higher morbidity and mortality, but also poses a threat for the quality of life, longevity, and well-being of dogs and cats. To date, strategies to prevent BW gain or to induce weight loss have had modest success in the pet population. In part, due to the complexity and the multifactorial nature of this disease, which involves pet-human interaction, environmental and dietary factors, and an intertwined metabolic process that still is not fully understood. As such, research methods to investigate the role of physiological hormones and dietary management on mechanisms related to the control of feelings of satiety and hunger in pet animals is warranted. Increasing interest exists in exploring gut chemosensing mechanisms, the crosstalk between metabolic-active tissues, and the interface between the gut microbiota and the nervous system (gut-brain axis). The noninvasive nature of research conducted in companion animals focuses on systemic approaches to develop environmental, nutritional, or therapeutic interventions that can be translated from research settings to pet-owned households. Because the majority of the pet population is spayed or neutered, it is important to determine the effect that sex hormones might have on appetite regulation and fasting metabolic rate of these animals. In general, studies have revealed that gonadectomy may establish a new "set point" characterized by increased food intake and BW, accompanied by physiological and behavioral changes. Some studies have also shown associations between gonadectomy and alterations in appetite-related hormones (e.g., ghrelin, leptin, adiponectin, glucagon-like peptide-1). Manipulation of macronutrients in diets of dogs and cats have also been investigated as a mean to improve satiety. Most of the research in this area has focused on high-protein diets, predominantly, for cats, and the use of dietary fiber sources of contrasting fermentability and viscosity profiles. Dietary fibers may affect the production of fermentative end products and gut microbiome, digestive and absorptive processes, appetite-related hormones, and promote "gut fill" and satiety. More recent studies have reported profound effects of dietary manipulation on the phylogeny and functional capacity of gut microbial communities of dogs and cats.