Reproductive performance and pre-weaning mortality: Preliminary analysis of 27,221 purebred female dogs and 204,537 puppies in France.

The objective of this study was to describe efficiency of reproduction of purebred dogs in field breeding conditions, from mating to weaning in France. Data were collected between 2010 and 2014 in 5,667 French breeding kennels via a reproduction management software (Breeding Management System, Royal Canin, Aimargues, France). Effect of breed size (Mini: adult body weight <10 kg; Medium: 10-25 kg; Maxi: 25-40 kg; Giant: >40 kg), age of dam and male on pregnancy rate, abortion rate and litter size were evaluated by multivariable models. Data on 45,913 heats (all with mating), from 27,221 bitches from 248 breeds, were analysed. At mating, mean age (±SD) was 3.1 ± 1.8 years for bitches and 3.3 ± 2.0 for males. Males originated from the same kennel as the females in 88.5% of the matings. Based on breeder's evaluation of the pregnancy status, pregnancy rate (number of pregnant females based on breeders declaration/number of heats) was 87.8% and abortion rate was 6.8%. Finally, 81.9% of the mated females gave birth to a litter. On 37,946 litters (204,537 puppies), mean litter size was 5.4 ± 2.8 puppies (range 1-24), which was influenced by breed size and dam age (p < .0001). Stillbirth rate was 7.4% and puppy mortality rate (stillbirth + mortality until 2 months of age) was 13.4%. Prolificacy and puppy mortality rates were affected by breed size and within a breed size, by breed. Despite probable approximations (as data originate from breeders declaration), this large-scale analysis provides reference values on reproductive performance in dogs.

Epidemiological analysis of reproductive performances and kitten mortality rates in 5,303 purebred queens of 45 different breeds and 28,065 kittens in France.

Reproduction management and performances are evaluated in the feline species only through a limited number of animals and studies. Our objective was to provide reference figures in purebred cats, from a large-scale sample. Data were collected from an online software dedicated to cattery management (Breeding Management System®, BMS, Royal Canin, Aimargues, France). Information was recorded on a voluntary basis by French breeders between 2011 and 2014. Data were anonymously transferred for analysis. A total of 9,063 oestrous periods (in contact with a male) from 5,303 queens (45 breeds) were recorded from 1,521 breeders. Most matings (70.1%) occurred during increasing day length periods. The mean age at mating (±SD) was 2.7 ± 1.6 years for queens and 2.9 ± 1.9 years for tomcats. Pregnancy rate (based on breeders declaration) was 85.2%. Among queens declared pregnant, 8.4% failed to maintain pregnancy. Globally, 78% of the mated females gave birth to 28,065 kittens within 7,075 L. Mean litter size was 4.0 ± 1.9 kittens among which 8.5% were stillborn. Neonatal and paediatric mortality rate was 8.2%. In total, 16.0% of kittens born died before weaning. The results of this study are based on the largest feline database ever analysed. The figures collected can thus be used as reference to define average reproductive performances in numerous breeds for cat breeders. Further analysis will identify factors influencing reproductive performances and early mortality in the feline species.

Natural and artificial hyperimmune solutions: Impact on health in puppies.

Colostrum and milk are complex mammary secretions providing the puppy with many nutritional and immunological factors, which play a crucial role for its correct development and survival. In the case of colostrum and/or milk intake deficiency, puppies are at increased risk of infectious diseases. This work reviews the various nutritional hyperimmune supplementations proposed to provide a passive immune protection and to positively impact puppies' health. Some strategies rely on canine immunoglobulins: canine colostrum banking and canine serum/plasma supplementation. Others involve heterologous sources of antibodies and other immune factors: bovine colostrum or hyperimmune egg powder. Among the different solutions evaluated from birth to weaning, canine plasma and hyperimmune egg powder showed promising beneficial effect on puppies' health. Canine plasma seems to positively impact not only growth (increased growth during the neonatal period), but also digestive health (higher species richness of intestinal microbiota) and the general health (tendency of lower morbidity). Puppies supplemented with hyperimmune egg powder presented increased neonatal growth and decreased risk of canine parvovirus infection. Nevertheless, natural canine maternal colostrum and milk ingestion remains the optimal guarantee for puppies' health and survival, as a source of immunity, energy and growth factors.

Influence of Breed Size, Age, Fecal Quality, and Enteropathogen Shedding on Fecal Calprotectin and Immunoglobulin A Concentrations in Puppies During the Weaning Period.

BACKGROUND: Fecal calprotectin and immunoglobulin A (IgA) are markers of intestinal inflammation and immunity in adult dogs. HYPOTHESIS: Fecal calprotectin and IgA concentrations in puppies are not influenced by fecal moisture in puppies but by enteropathogen shedding. ANIMALS: Three hundred and twenty-four puppies. METHODS: Fecal consistency was assessed by gross examination. Fecal moisture was evaluated before and after lyophilization. Canine parvovirus and coronavirus were detected in feces by qPCR and qRT-PCR respectively. Giardia intestinalis antigen was quantified by ELISA. The standard McMaster flotation technique was used to detect eggs and oocysts in feces. Fecal calprotectin and IgA concentrations were quantified by in-house radioimmunoassays. RESULTS: For each marker (IgA and calprotectin), a strong positive correlation was observed between concentration in fresh feces and concentration in fecal dry matter. 75.6% of the puppies were found to be infected by at ≥1 of the enteropathogens evaluated. Fecal calprotectin concentration was significantly influenced by age (P = .001), with higher concentrations in younger puppies, but not by viral (P = .863) or parasitic infection (P = .791). Fecal IgA concentration was significantly influenced by enteropathogen shedding (P = .01), with a lower fecal IgA concentration in puppies shedding at ≥1 enteropathogen compared to puppies without any enteropathogen shedding, but not by age. CONCLUSIONS: Fecal calprotectin and IgA are of no diagnostic value to detect presence of enteropathogens in clinically healthy puppies or puppies with abnormal feces, but could help to better understand the maturation of digestive tract.

Differential impact of birth weight and early growth on neonatal mortality in puppies.

Breeding kennels face a high rate of neonatal mortality, on which the impact of nutrition remains to be determined. This study was designed to evaluate the impact of birth weight (reflecting intrauterine growth) and early growth rate (reflecting colostrum intake) on risk of neonatal mortality in puppies and to determine the critical thresholds of both parameters. Puppies from various breeds were weighed at birth ( = 514) and at 2 d of age, and the growth rate over that period (early growth rate) was calculated for all survivors ( = 477). Linear mixed models evaluated the effect of birth weight on mortality between birth and 2 d of age and the effect of both birth weight and early growth rate on mortality between 2 and 21 d of age. Birth weight was influenced by litter size ( = 0.003), with more low-birth-weight puppies (the lightest 25% within a breed size) in large litters compared with smaller litters. Mortality over the first 2 d after birth was associated with birth weight ( < 0.001), with 81.1% of dying puppies characterized by a low birth weight. Mortality between 2 and 21 d of age was not related to birth weight but was found to be associated with early growth rate ( < 0.001), with higher risk of death in puppies with growth rate at or below -4% after the first 2 d of life. This study demonstrates the differential effect of intrauterine nutrition impacting mortality during the first 2 d of life and that of colostrum intake impacting mortality until 21 d of life. Birth weight and early growth rate thresholds provided in this study allow identification of puppies at risk, whereby provision can be made for adequate nursing to increase their chances to survive.

Inadequate passive immune transfer in puppies: definition, risk factors and prevention in a large multi-breed kennel.

The prevalence of neonatal mortality is high in the canine species and far from well-studied. In most domestic neonates, an appropriate colostrum intake is a key element of the control of neonatal mortality. The aim of this study was to evaluate the impact of passive immune transfer on puppy mortality, assessed through serum immunoglobulin G (IgG) concentration at 2 days of age. Factors impacting passive immune transfer and the value of an oral immunoglobulin supplementation to prevent it were also analyzed. A total of 149 puppies from 34 litters (12 breeds) within one breeding kennel were included. Blood samples were collected at 2 days of age and colostrum was collected from their dams 1 day after whelping to assay IgG concentration. Puppies were weighed at birth and at 2 days of age for calculation of growth rate. Mortality was recorded until 3 weeks of age. Seventy randomly assigned puppies were orally supplemented with hyper-immunized adult plasma twice within the first 8h of life. IgG concentration at 2 days of age was significantly correlated with weight gain during the first 2 days of life. The multivariable model with litter as a random effect demonstrated that neonatal mortality was not influenced by breed size, sex, supplementation, litter size, nor colostrum IgG concentration, but by puppy IgG concentration at 2 days of age. According to the ROC curve, the minimal IgG concentration at and below which puppies were at higher risk of death was determined at 230 mg/dl. Puppy IgG concentration was significantly associated with growth rate, but not with breed size, sex, supplementation, litter size or colostrum IgG concentration in a multivariable model with litter as a random effect. This study demonstrates that neonatal mortality in puppies is related to the quality of passive immune transfer. The oral supplementation with hyper-immunized canine plasma neither decreased risk of mortality, nor improved serum IgG concentration at 2 days of age in puppies. Attention must thus be paid to early colostrum intake to control the neonatal mortality in puppies.

Diagnosis of endometritis in the bitch: a new approach.

There are a few investigations into endometritis in the bitch and its relationship with failure to conceive remains unclear. This may be because of the difficulty in collecting uterine samples for further investigations. Recently, transcervical catheterization by vaginal endoscopy has been introduced allowing the evaluation of the endometrium. In this study, uterine cytology and bacteriology were evaluated in 26 infertile bitches. Endometritis was bacterial in origin in most cases (70% of affected bitches), but these results may be underestimated, as some other pathogens (anaerobic bacteria, mycoplasms and fungi) were not investigated. Endometritis, in our opinion, should be investigated in each case of unexplained infertility in bitches. The method used here seems reliable although defining more accurate classification criteria will improve the efficiency of this non-invasive technique.

Thyroid function and infertility in the dog: a survey in five breeds.

In our study, a clinical and reproductive examination was undertaken in 204 dogs of five different breeds. Thyroxine and thyroid-stimulating hormone plasma concentrations were assayed in order to assess the real incidence of hypothyroidism associated with reproductive disease. Among these animals, only two breeds were affected by hypothyroidism (4.5% of the Dogue de Bordeaux and 2.4% of the Leonbergers). Moreover, these animals did not suffer from any reproductive disease. Our study showed also that 70% of the male Dogue de Bordeaux were hypothyroxinemic compared with Great Danes, English Mastiff and Leonbergers whose male population was 100% normothyroidic. We found the same tendency in bitches. In our data, there was no difference in thyroxin plasma concentrations between normo- and hypofertile dogs, but our results were not statistically significant.