Giardia duodenalis Colonization Slightly Affects Gut Microbiota and Hematological Parameters in Clinically Healthy Dogs.

Giardia duodenalis (Giardia) is a worldwide cause of acute diarrheal disease both in humans and animals. The primary aim of this study was to investigate possible variations in gut microbiota in a population of asymptomatic dogs (n = 31), naturally infected or not by Giardia. Gut microbiota and the hematological, biochemical, and fecal parameters related to intestinal function were investigated. Giardia infection was associated with a significant shift of beta diversity, showing a relevant reduction of Gammaproteobacteria and an increase of Fusobacteria in male-positive dogs if compared with negatives. A significant imbalance of different bacterial taxa, with particular reference to the Erysipelotrichales, Lactobacillales, Clostridiales, and Burkholderiales orders, was observed, with the first two being higher in Giardia-positive dogs. Giardia-positive males displayed significantly higher values of cCRP than negative males as well as positive females, supporting the presence of a pro-inflammatory state. Taken together, these results indicate that the presence of Giardia does not substantially modify the microbial ecology of the intestine nor the hematological markers of disease. Thus treatments against Giardia should be considered with caution in asymptomatic subjects.

Serum concentrations of leptin in pregnant and non-pregnant bitches.

Leptin regulates body weight and several physiological processes including reproduction. We evaluated the circulating levels of leptin in pregnant and non-pregnant bitches as well as their correlation with body weight, food intake and number of foetuses. Nineteen healthy German shepherd bitches were used and divided in two groups (pregnant n = 12 and non-pregnant n = 7). Blood samples were collected every 15 days starting from ovulation (Day 0) throughout pregnancy (pregnant group, P) or throughout luteal phase (non-pregnant group, NP) In pregnant bitches, leptin concentrations increased from the day of ovulation (1.32 ± 0.06 ng/ml) up to day 45 (1.51 ± 0.06 ng/ml; p < .01) and returned to baseline values from day 60 post-ovulation. In non-pregnant bitches, leptin concentrations remained constant throughout the whole observation period (estimated marginal mean ± SE=1.33 ± 0.38 ng/ml). Pairwise comparisons showed significant differences between P and NP at day 45 post-ovulation (p < .05). Multivariable models indicated that, controlling for time and litter size, there was a positive relationship between leptin concentration and BW (p < .05) although Pearson coefficients showed that the correlation between BW and leptin was only significant in NP animals at day 45 (r = 0.76, p < .05). The multivariable approach also suggested that, holding BW and time constant, leptin concentrations tend to increase as the number of puppies increased (p = .06). Our study supports indirectly the contribution of the feto-placental unit to the circulating maternal leptin concentration.

Benefits of dietary supplements on the physical fitness of German Shepherd dogs during a drug detection training course.

A high standard of physical fitness is an essential characteristic of drug detection dogs because it affects not only their ability to sustain high activity levels but also their attention and olfaction efficiency. Nutritional supplements could improve physical fitness by modulating energy metabolism, oxidative processes, and perceived fatigue. The aim of this study was to investigate the physiological and biochemical changes induced by submaximal exercise on drug detection dogs (German Shepherd breed) and to assess whether a dietary supplement improves their physical fitness. During a drug detection dog training course, seven dogs were fed with a basal diet (Control Group) for three-month period, while a further seven dogs were fed with a basal diet as well as a daily nutritional supplement containing branched-chain and limiting amino acids, carnitine, vitamins, and octacosanol (Treatment Group). At the end of this period, individual physical fitness was assessed by making each subject take a graded treadmill exercise test. A human heart rate monitor system was used to record the dog's heart rate (HR) during the treadmill exercise and the subsequent recovery period. The parameters related to HR were analysed using nonparametric statistics. Blood samples were collected before starting the nutritional supplement treatment, before and after the treadmill exercise and following recovery. Linear mixed models were used. The dietary supplements accelerated HR recovery, as demonstrated by the lower HR after recovery (P<0.05) and Time constants of HR decay (P<0.05), and by the higher Absolute HR Recovered (P<0.05) recorded in the Treatment group compared with the Control dogs. The supplemented dogs showed the lowest concentrations of creatine kinase (CK; P<0.001), aspartate aminotransferase (AST, P<0.05) and non-esterified fatty acids (NEFA; P<0.01) suggesting a reduction in muscle damage and improvement of energy metabolism. These data suggest that this combined supplement can significantly enhance the physical fitness of drug detection dogs.

Detection by hemi-nested reverse transcription polymerase chain reaction and genetic characterization of wild type strains of Canine distemper virus in suspected infected dogs.

A new highly sensitive and specific hemi-nested reverse transcription polymerase chain reaction (RT-PCR) assay was applied to detect nucleoprotein (NP) gene of Canine distemper virus (CDV) in samples collected from dogs showing respiratory, gastrointestinal, and neurological signs. Thirty-eight out of 86 samples were positive suggesting that despite the vaccination, canine distemper may still represent a high risk to the canine population. The 968 base pair (bp) fragments from the hemagglutinin (H) gene of 10 viral strains detected in positive samples were amplified and analyzed by restriction fragment length polymorphism (RFLP) using AluI and PsiI enzymes in order to differentiate among vaccine and wild-type CDV strains and to characterize the field viral strains. The products of the both enzymatic digestions allowed identification all viruses as wild strains of CDV. In addition, the RFLP analysis with AluI provided additional information about the identity level among the strains analyzed on the basis of the positions of the cleavage site in the nucleotide sequences of the H gene. The method could be a more useful and simpler method for molecular studies of CDV strains.

Morbilliviral encephalitis in a striped dolphin Stenella coeruleoalba calf from Italy.

A free-living, striped dolphin Stenella coeruleoalba calf was stranded on the Latium coast of Italy in November 2009. Significant neuropathological findings included non-suppurative meningoencephalitis, microgliosis, neuronal degeneration, astrocytosis, and occasional multinucleate syncytia. Immunohistochemistry (IHC) and reverse transcription polymerase chain reaction (RT-PCR) for Morbillivirus were positive exclusively from the brain, with morbilliviral antigen and nucleic acid being detected in neurons and, to a lesser extent, in astrocytes. A low neutralizing antibody titer (1:10) against Morbillivirus (Canine distemper virus, CDV) was also found in blood serum, with no simultaneous presence of serum antibodies to Brucella spp. or Toxoplasma gondii. Furthermore, no pathogenic bacteria were isolated from any tissue or biological sample. This is the second report of morbilliviral encephalitis in a striped dolphin stranded along the Italian coastline in a 16 yr period (1993 to 2009). The neurohistopathological, IHC, and biomolecular features of this case are of additional interest, as antigenic and genomic positivity were exclusively confined to the brain of this dolphin, which may have acquired morbilliviral infection either postnatally or transplacentally.