Prioritization of Appearance over Health and Temperament Is Detrimental to the Welfare of Purebred Dogs and Cats.

Fashions in the appearance of purebred dogs and cats are encouraged by celebrity culture, social media, and online impulse buying. The popularity of characteristics perceived as cute, quirky, and anthropomorphic has driven increasingly exaggerated breed features appealing to aesthetics rather than health. 'Hypertypes' of some breeds have emerged that take a breed's distinctive appearance to extremes beyond the intended interpretation of breed standards. This has severe, direct and indirect health and welfare consequences. Extreme conformations are associated with chronic health conditions including brachycephalic obstructive airway disorder, ocular, dental, skin, and musculoskeletal disorders. Puppy and kitten farms and illegal traders that meet the demand for hypertypes are associated with poor husbandry that neglects the physical, behavioral, and mental health of parents and offspring. A multidimensional approach involving collaboration between breeders, geneticists, owners, veterinarians, kennel clubs, cat fanciers' associations, animal charities, the academic and research communities, commercial enterprises, and governments is needed to safeguard breeds and tackle these challenges. There are many ongoing initiatives by national kennel clubs and global partnerships to educate pet owners and support responsible pet ownership and sustainable breeding. The resounding message is that health, temperament, and well-being must be prioritized over appearance.

Association between Birth Weight and Mortality over the Two First Months after Birth in Feline Species: Definition of Breed-Specific Thresholds.

In many species, low birth weight is identified as a major determinant for neonatal survival. The objectives of the present study were (i) to assess, in a large feline purebred population, the impact of birth weight on 0-2 months mortality in kittens, and (ii) if such mortality occurs, to define cut-off values for birth weight to identify at-risk kittens. Data from 5596 kittens from 15 breeds and provided by 194 French breeders were analysed. A logistic mixed model was used to identify low birth weight, being a male, and being born in a large litter as significant risk factors for kitten mortality during the first two months after birth. Classification and regression tree analysis was used to define the thresholds, first at the species level and, when possible, at the breed level. Two thresholds were defined to group kittens into three categories: low, moderate, or high risk of 0-2 months mortality (normal, low, and very low birth weight, respectively). In our population, 19.7% of the kittens were classified as low birth weight and 1.9% as very low birth weight. Critical thresholds may differ between breeds with similar birth weight distributions and equivalent mortality rates (e.g., Russian Blue/Nebelung vs. Egyptian Mau). These critical birth weight thresholds, established in 15 breeds, could be used to identify kittens requiring more intensive nursing to improve survival.

Relative Impact of Birth Weight and Early Growth on Neonatal Mortality in Puppies.

Puppy survival during their first weeks of life can be improved, and early detection of puppies with increased mortality risk is one of the keys to success. In the canine species, the few studies on this subject focused on birth weight, which reflects intrauterine growth. The present work aimed to explore the interconnections between birth weight, early growth and survival until two months of life in the canine species. In total, data from 8550 puppies born in 127 French breeding kennels were analysed. Five different growth rates were calculated to reflect the growth of puppies during their first week of life. Low-birth-weight puppies had lower growth than normal-birth-weight puppies over the first two days of life but higher growth rates thereafter. Growth-rate thresholds allowing the identification of puppies at higher risk of mortality during their first two months of life were lower for low-birth-weight puppies. These thresholds will help breeders and veterinarians to identify puppies at risk with particular needs for monitoring and nursing to improve their chances of survival.

Uterine issues in infertile queens: Nine cases.

This prospective case series investigated potential uterine causes of infertility in queens. Purebred queens with infertility (failure to conceive, embryonic death, or failure to maintain pregnancy and produce viable kittens), but no other reproductive disorders were examined approximately 1-8 weeks before mating (Visit 1), 21 days after mating (Visit 2), and 45 days after mating (Visit 3) if pregnant at Visit 2. Investigations included vaginal cytology and bacteriology, urine bacteriology, and ultrasonography. At Visit 2 or 3, uterine biopsy or ovariohysterectomy was performed for histology. Of nine eligible queens, seven were non-pregnant by ultrasound at Visit 2 and two had lost pregnancies by Visit 3. Ovulation was confirmed by serum progesterone concentration in all queens. Ultrasonic appearance of the ovaries and uterus was compatible with a healthy status except for one queen with signs of cystic endometrial hyperplasia (CEH) and pyometra, a follicular cyst in another, and fetal resorptions in two queens. Six cats had histologic lesions of endometrial hyperplasia, including CEH (n=1). Only one cat had no histologic uterine lesions. Bacteria were cultured from vaginal samples in seven queens at Visit 1, (two were non-evaluable), and in five of seven queens sampled at Visit 2. Uterine cultures were negative except for the cat with pyometra. All urine cultures were negative. In summary, the most frequent pathology observed in these infertile queens was histologic endometrial hyperplasia, which can potentially inhibit embryo implantation and healthy placental development. This suggests that uterine disease might contribute substantially to infertility in purebred queens.

Growth charts for small sample sizes using unsupervised clustering: Application to canine early growth.

Breed-specific growth curves (GCs) are needed for neonatal puppies, but breed-specific data may be insufficient. We investigated an unsupervised clustering methodology for modeling GCs by augmenting breed-specific data with data from breeds having similar growth profiles. Puppy breeds were grouped by median growth profiles (bodyweights between birth and Day 20) using hierarchical clustering on principal components. Median bodyweights for breeds in a cluster were centered to that cluster's median and used to model cluster GCs by Generalized Additive Models for Location, Shape and Scale. These were centered back to breed growth profiles to produce cluster-scale breed GCs. The accuracy of breed-scale GCs modeled with breed-specific data only and cluster-scale breed GCs were compared when modeled from diminishing sample sizes. A complete dataset of Labrador Retriever bodyweights (birth to Day 20) was split into training (410 puppies) and test (460 puppies) datasets. Cluster-scale breed and breed-scale GCs were modelled from defined sample sizes from the training dataset. Quality criteria were the percentages of observed data in the test dataset outside the target growth centiles of simulations. Accuracy of cluster-scale breed GCs remained consistently high down to sampling sizes of three. They slightly overestimated breed variability, but centile curves were smooth and consistent with breed-scale GCs modeled from the complete Labrador Retriever dataset. At sampling sizes ≤ 20, the quality of breed-scale GCs reduced notably. In conclusion, GCs for neonatal puppies generated using a breed-cluster hybrid methodology can be more satisfactory than GCs at purely the breed level when sample sizes are small.

Birth weight in the feline species: Description and factors of variation in a large population of purebred kittens.

Birth weight is one of the earliest health parameters with short (neonatal period) and long term (adulthood) implications for an individual. The present work was conducted on the domestic cat, with the objective of determining factors affecting kitten birth weight. Data voluntarily shared by 139 French breeders allowed building a large dataset of purebred kittens (n = 3,547) from 15 breeds. A linear mixed model with queen and cattery as random terms was used to investigate variation factors of kitten birth weight such as breed, litter size, season of birth, age of the queen, presence of stillborn in the litter, sex of the kitten. The most important factor was breed which explained 25% of the variation in birth weight observed in the study population. The five other parameters were also significant but explained only a small additional part of the variance (less than 3% each). Analyses showed that kitten birth weight increased with the age of the queen, was higher in males than females and in litters without stillbirth than in litters with at least one stillborn. In addition, lower birth weights were recorded in summer and autumn compared to other seasons, and birth weight values decreased as the number of kittens in the litter increased. In order to group feline breeds according to their average birth weights and litter sizes, a K-means algorithm was used to identify three clusters among the 15 breeds represented (Group 1: small litter sizes/low birth weights; Group 2: large litter sizes/intermediate birth weights; Group 3: large litter sizes/high birth weights). This study, based on a large dataset established at the national scale, provides reference values of feline birth weights for breeders and veterinarians. The next step could be to explore the relationship between birth weight and neonatal mortality to help identify neonates requiring specific care.

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.

Management of Low Birth Weight in Canine and Feline Species: Breeder Profiling.

Low birth weight (LBW) has been identified as a major risk factor for neonatal mortality in many species. The aim of this survey was to determine the profiles of canine and feline breeders concerning their perceptions of, and management practices relating to, LBW individuals. An anonymous online survey was addressed to French cat and dog breeders in September 2019 via social networks. Multiple correspondence analysis and hierarchical clustering were used to explore breeders' profiles. Three clusters were identified among the 649 breeders included in this analysis. Cluster 1 (49%) included dog and cat breeders who weighed newborns (and thus identified LBW) and controlled nursing by the dam (controlled suckling) but did not warm them up. Cluster 2 breeders (21%) of both species did not weigh puppies or kittens to identify LBW or to monitor the evolution of their weight afterwards. Cluster 3 (30%) including mostly cat breeders who weighed neonates routinely as in Cluster 1, but they practiced artificial feeding rather than controlled suckling. This survey provides a basis for better understanding of perceptions and practices regarding LBW puppies and kittens. It will be useful to provide guidelines for neonatal management to increase their chances of survival.

Low and very low birth weight in puppies: definitions, risk factors and survival in a large-scale population.

BACKGROUND: Neonatal mortality (over the first three weeks of life) is a major concern in canine breeding facilities as an economic and welfare issue. Since low birth weight (LBW) dramatically increases the risk of neonatal death, the risk factors of occurrence need to be identified together with the chances and determinants of survival of newborns at-risk. RESULTS: Data from 4971 puppies from 10 breeds were analysed. Two birth weight thresholds regarding the risk of neonatal mortality were identified by breed, using respectively Receiver Operating Characteristics and Classification and Regression Tree method. Puppies were qualified as LBW and very low birth weight (VLBW) when their birth weight value was respectively between the two thresholds and lower than the two thresholds. Mortality rates were 4.2, 8.8 and 55.3%, in the normal, LBW and VLBW groups, accounting for 48.7, 47.9 and 3.4% of the included puppies, respectively. A separate binary logistic regression approach allowed to identify breed, gender and litter size as determinants of LBW. The increase in litter size and being a female were associated with a higher risk for LBW. Survival for LBW puppies was reduced in litters with at least one stillborn, compared to litters with no stillborn, and was also reduced when the dam was more than 6 years old. Concerning VLBW puppies, occurrence and survival were influenced by litter size. Surprisingly, the decrease in litter size was a risk factor for VLBW and also reduced their survival. The results of this study suggest that VLBW and LBW puppies are two distinct populations. Moreover, it indicates that events and factors affecting intrauterine growth (leading to birth weight reduction) also affect their ability to adapt to extrauterine life. CONCLUSION: These findings could help veterinarians and breeders to improve the management of their facility and more specifically of LBW puppies. Possible recommendations would be to only select for reproduction dams of optimal age and to pay particular attention to LBW puppies born in small litters. Further studies are required to understand the origin of LBW in dogs.

Plasma volume and arterial stiffness in the cardiac alterations associated with long-term high sodium feeding in rats.

BACKGROUND: Rats fed an early and long-term high-salt diet (HS, NaCl 8%) developed significant cardiovascular hypertrophy without major changes in blood pressure. The mechanism of this cardiac hypertrophy has not been yet elucidated. METHODS: In the present work, we assessed the influence of volume overload and arterial stiffness on the structural and functional cardiac changes induced by a high salt feeding from weaning to 5 months of age in Sprague-Dawley rats. RESULTS: Cardiac hypertrophy in HS rats was associated with clear augmentation in the size of left ventricular (LV) cardiomyocyte as compared with rats fed regular diet (NS). Echocardiography revealed a marked increase in relative wall thickness. Of note, no alteration of global and regional systolic and diastolic function was detected in HS rats. High sodium consumption was associated with a slight increase in aortic mean and pulse pressure (PP) without effect on pulse wave velocity (PWV) and elastic modulus. Plasma volume and central venous pressure were higher in HS than NS rats. Whereas plasma endothelin level was twofold higher in HS than in NS rats, LV endothelin level was similar in both groups. Treatment by the endothelin receptors blocker bosentan had no detectable effect on the changes induced by HS diet. CONCLUSIONS: High sodium intake was associated with concentric cardiac hypertrophy without change of systolic and diastolic function. Aortic rigidity was not a determinant of cardiac hypertrophy. Beside a likely direct effect of sodium on cardiovascular system the slight increase in arterial pressure and plasma volume play a role.

Renal function and structure in a rat model of arterial calcification and increased pulse pressure.

Clinical studies suggest a strong link between tissue calcification and pressure hyperpulsatility in end stage renal disease patients. Using a Wistar rat model of arterial elastocalcinosis and hyperpulsatility [vitamin D and nicotine (VDN) treatment], we evaluated the relative importance of tissue calcification and hyperpulsatility in the etiology of renal failure. VDN rats showed significant increases in aortic wall calcium content (50 times; 992+/-171 vs. control 19+/-1 micromol/g dry wt) and pulse pressure (1.5 times; 61+/-4 vs. control 40+/-2 mmHg). Significant renal calcification (16 times; 124+/-27 vs. control 8.1+/-0.7 micromol/g dry wt) occurred mainly within the media of the preglomerular vasculature and in the areas of interstitial fibrosis in VDN. Extensive renal damages (5 times; 26+/-5% of collapsed-atrophic or sclerotic glomeruli, or glomerular cysts vs. control 5.2+/-0.3%; 28 times; 61+/-12% areas of focal, cortical areas exhibiting interstitial fibrosis per section vs. control 2.2+/-0.6%) were observed histologically. The glomerular filtration rate significantly decreased (880+/-40 vs. control 1,058+/-44 microl.min(-1).g kidney wt(-1)). Albuminuria increased six times (1.6+/-0.4 vs. control 0.27+/-0.04 mg/24 h). There were significant linear relationships between albuminuria and pulse pressure (r2=0.408; n=24) or renal calcium content (r2=0.328; n=24; P<0.05) and between glomerular filtration rate and pulse pressure (r2=0.168; n=27). To our knowledge, this study provides the first evidence of links between both 1) hyperpulsatility and renal dysfunction, and 2) renal calcification and renal dysfunction. Given the increasing frequency of end-stage renal disease, this model could prove useful for preclinical evaluation of drugs that prevent or attenuate hyperpulsatility and/or tissue calcification.

Effects of an aging vascular model on healthy and diseased hearts.

The vitamin D(3) and nicotine (VDN) model is a model of isolated systolic hypertension (ISH) due to arterial calcification raising arterial stiffness and vascular impedance similar to an aged and stiffened arterial tree. We therefore analyzed the impact of this aging model on normal and diseased hearts with myocardial infarction (MI). Wistar rats were treated with VDN (n = 9), subjected to MI by coronary ligation (n = 10), or subjected to a combination of both MI and VDN treatment (VDN/MI, n = 14). A sham-treated group served as control (Ctrl, n = 10). Transthoracic echocardiography was performed every 2 wk, whereas invasive indexes were obtained at week 8 before death. Calcium, collagen, and protein contents were measured in the heart and the aorta. Systolic blood pressure, pulse pressure, thoracic aortic calcium, and end-systolic elastance as an index of myocardial contractility were highest in the aging model group compared with MI and Ctrl groups (P(VDN) < 0.05, 2-way ANOVA). Left ventricular wall stress and brain natriuretic peptide (P(VDNxMI) = not significant) were highest, while ejection fraction, stroke volume, and cardiac output were lowest in the combined group versus all other groups (P(VDNxMI) < 0.05). The combination of ISH due to this aging model and MI demonstrates significant alterations in cardiac function. This model mimics several clinical phenomena of cardiovascular aging and may thus serve to further study novel therapies.

Ventricular-arterial coupling in a rat model of reduced arterial compliance provoked by hypervitaminosis D and nicotine.

The vitamin D(3) and nicotine (VDN) model is one of isolated systolic hypertension (ISH) in which arterial calcification raises arterial stiffness and vascular impedance. The effects of VDN treatment on arterial and cardiac hemodynamics have been investigated; however, a complete analysis of ventricular-arterial interaction is lacking. Wistar rats were treated with VDN (VDN group, n = 9), and a control group (n = 10) was included without the VDN. At week 8, invasive indexes of cardiac function were obtained using a conductance catheter. Simultaneously, aortic pressure and flow were measured to derive vascular impedance and characterize ventricular-vascular interaction. VDN caused significant increases in systolic (138 +/- 6 vs. 116 +/- 13 mmHg, P < 0.01) and pulse (42 +/- 10 vs. 26 +/- 4 mmHg, P < 0.01) pressures with respect to control. Total arterial compliance decreased (0.12 +/- 0.08 vs. 0.21 +/- 0.04 ml/mmHg in control, P < 0.05), and pulse wave velocity increased significantly (8.8 +/- 2.5 vs. 5.1 +/- 2.0 m/s in control, P < 0.05). The arterial elastance and end-systolic elastance rose significantly in the VDN group (P < 0.05). Wave reflection was augmented in the VDN group, as reflected by the increase in the wave reflection coefficient (0.63 +/- 0.06 vs. 0.52 +/- 0.05 in control, P < 0.05) and the amplitude of the reflected pressure wave (13.3 +/- 3.1 vs. 8.4 +/- 1.0 mmHg in control, P < 0.05). We studied ventricular-arterial coupling in a VDN-induced rat model of reduced arterial compliance. The VDN treatment led to development of ISH and provoked alterations in cardiac function, arterial impedance, arterial function, and ventricular-arterial interaction, which in many aspects are similar to effects of an aged and stiffened arterial tree.

Pioglitazone improves aortic wall elasticity in a rat model of elastocalcinotic arteriosclerosis.

Specific treatment of age-related aortic wall arteriosclerosis and stiffening is lacking. Because ligands for peroxisome proliferator-activated receptor gamma have beneficial effects on the arterial wall in atherosclerosis, via an antiinflammatory mechanism, we investigated whether long-term pioglitazone (Pio) treatment protects against another form of vascular wall disease, arteriosclerosis. We evaluated, in a rat model of elastocalcinotic arteriosclerosis (hypervitaminosis D and nicotine [VDN]), whether Pio (3 mg . kg(-1) per day for 1.5 month PO) attenuated arteriosclerosis and its consequences: aortic wall rigidity, increased aortic pulse pressure, and left ventricular hypertrophy. In VDN rats, medial calcification was associated with monocyte/macrophage infiltration and induction of tumor necrosis factor alpha and interleukin 1beta. Pio increased nuclear peroxisome proliferator-activated receptor gamma immunostaining in the aortic wall, decreased tumor necrosis factor alpha (P <0.05 versus VDN Pio-), tended to decrease interleukin 1beta mRNA expression (P =0.08 versus VDN Pio-), blunted aortic wall calcification (271+/-69, P <0.05 versus VDN Pio- 562+/-87 micromol . g(-1) dry weight) and prevented fragmentation of elastic fibers (segments per 10,000 microm2: 8.4+/-0.3; P <0.05 versus VDN Pio- 10.5+/-0.6). Pio reduced aortic wall stiffness (elastic modulus/wall stress: 4.8+/-0.6; P <0.05 versus VDN Pio- 10.0+/-1.6), aortic pulse pressure (30+/-2 mm Hg; P <0.05 versus VDN Pio- 39+/-4) and left ventricular hypertrophy (1.58+/-0.05 g . kg(-1); P <0.05 versus VDN Pio- 1.76+/-0.06). In conclusion, long-term Pio treatment attenuates aortic wall elastocalcinosis and, thus, lowers aortic wall stiffness, aortic pulse pressure, and left ventricular hypertrophy.