Age-associated and breed-associated variations in haematological and biochemical variables in young labrador retriever and miniature schnauzer dogs

Adjuvant Chemotherapy Is Associated With Prolonged Survival Time in Small-Breed Dogs Undergoing Amputation for Appendicular Osteosarcoma

Adjuvant chemotherapy is a well-established treatment for large-breed dogs with appendicular osteosarcoma; however, it is unclear if it improves outcomes in small-breed dogs due to limited focused studies. This retrospective study aimed to investigate the oncologic outcomes of dogs weighting less than 15 kg with appendicular osteosarcoma that underwent curative resection with or without postoperative adjuvant chemotherapy. Endpoints were time to distant progression (TTDP) and overall survival (OS). Medical records from multiple institutions were reviewed, and 43 dogs were included in the analysis: 17 underwent surgery alone and 26 also received adjuvant chemotherapy. The median TTDP for all dogs was 265 days, with no significant difference between treatment groups. The median OS for all dogs was 270 days, and it was significantly different between amputated dogs (150 days) and those also receiving adjuvant chemotherapy (353 days, p = 0.002). In our cohort, osteosarcoma in small breeds behaved as aggressive as in large breeds. Adjuvant chemotherapy may prolong survival. Future randomised studies are needed to provide definitive evidence on the necessity of adjuvant chemotherapy to address metastatic spread in small-breed dogs with appendicular osteosarcoma.

Evaluation of urine protein to creatinine ratio in sighthound breeds

The breed can influence the results of haematological and biochemical blood tests, with sighthounds traditionally mentioned. It may also affect certain urinary parameters. This study aimed to compare urinary protein and creatinine concentrations and their ratio (UPC, urine protein to creatinine ratio) between sighthounds and non-sighthounds and to evaluate these parameters in various sighthound breeds. Urine samples from clinically healthy dogs were collected via normal voiding, representing both sighthound and non-sighthound breeds. The protein and creatinine concentrations in the urine samples were determined, and their ratio was subsequently calculated. A total of 191 urine samples from sighthounds and 90 urine samples from non-sighthound breeds used as a control group were evaluated in the study. In sighthounds, significantly lower urinary protein concentration (248.8 mg/l and 299.8 mg/l, respectively; P = 0.045) and significantly higher urinary creatinine concentration (23.0 mmol/l and 17.5 mmol/l, respectively; P = 0.000) and lower UPC values (0.13 and 0.18, respectively; P = 0.000) were observed in comparison to the entire control group. The UPC values were found to be significantly lower in Greyhounds and Spanish Greyhounds compared with non-sighthounds. Although statistically significant changes were identified, they are unlikely to be of great clinical importance.

Hematologic parameters in female alpacas during age progression: a retrospective study

Alpacas, like all camelids, have elliptical red blood cells (RBCs) in contrast to other mammals. This particular shape is important for increased osmotic resistance and stability. Age-related changes in the RBC count are known in other species, with alterations in both red and white blood cells being described. In alpacas, there are few data on age-related changes, and only a comparison of crias with adult animals. We characterized age-related hematologic changes in a study of 21 female alpacas from a research herd. A total of 87 records of clinically healthy alpacas of different ages were statistically analyzed retrospectively from the hematologic records over a nine-year period. Significant positive correlations of age with hemoglobin (Hb), HCT, MCV, MCH, neutrophils, platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) were found as well as significant negative correlations of age with lymphocytes in addition to lymphocyte-to-monocyte ratio (LMR). A paired comparison of eight older animals in the herd at three different ages also showed significant differences in the parameters Hb, HCT, MCV, MCH, MCHC, lymphocytes, eosinophils and neutrophils. Similar changes in hematologic parameters have been reported in other species and should be taken into account when interpreting hematologic results in alpacas.

Computed tomographic measures of renomegaly vary among dogs with different types of congenital portosystemic shunts

Renomegaly has been reported in dogs with congenital portosystemic shunts (PSS). However, no study has objectively evaluated the degree of renomegaly in dogs with different types of PSS. The purpose of this retrospective, analytical, cross-sectional study was to determine kidney size (renal length-to-L2 vertebral body ratio; RL/L2 ratio) using CT in dogs with different types of PSS and correlate with clinical information. A medical record search for dogs with a PSS diagnosed using CT between 2016 and 2020 was conducted. Breed, age, sex, body weight, and biochemistry results were recorded. Kidney and L2 vertebral body lengths were measured using multiplanar reformatted CT images, and the RL/L2 ratio was calculated. Dogs were categorized into four groups based on PSS morphology for comparisons: intrahepatic (IH; n = 19), extrahepatic portocaval (EHPC; n = 20), extrahepatic portoazygos (EHPA; n = 7), or extrahepatic portophrenic (EHPP, n = 7). The RL/L2 ratio (mean ± SD) was largest in IH (3.55 ± 0.38) and EHPC (3.55 ± 0.38), followed by EHPP (3.10 ± 0.23), and EHPA (2.78 ± 0.18). RL/L2 ratio was significantly larger in EHPC and IH (vs. EHPA and EHPP [P < .01]). Significant correlations between kidney size and creatinine, alkaline phosphatase, albumin, total protein, and ammonia were present. Renomegaly was observed in 86.8% of dogs with PSS overall, but it was uncommon in dogs with EHPA and less common in dogs with EHPP, as these two groups showed clinical signs later in life, made evident by older age at presentation. The authors suggest that the severity of hepatic dysfunction and the shunted blood volume may influence the development of renomegaly in dogs with PSS.

Comparative plasma and urine metabolomics analysis of juvenile and adult canines

Background and aims

The metabolomic profile of a biofluid can be affected by age, and thus provides detailed information about the metabolic alterations in biological processes and reflects the in trinsic rule regulating the growth and developmental processes.

Methods

To systemically investigate the characteristics of multiple metabolic profiles associated with canine growth, we analyzed the metabolomics in the plasma and urine samples from 15 young and 15 adult beagle dogs via UHPLC-Q-TOFMS-based metabolomics. Blood routine and serum biochemical analyses were also performed on fasting blood samples.

Results

The metabolomics results showed remarkable differences in metabolite fingerprints both in plasma and urine between the young and adult groups. The most obvious age-related metabolite alterations include decreased serumlevels of oxoglutaric acid and essential amino acids and derivatives but increased levels of urine levels of O-acetylserine. These changes primarily involved in amino acid metabolism and bile secretion pathways. We also found that the levels of glutamine were consistently higher in both serum and urine of adults, while N-acetylhistamine and uracil concentrations were much lower in the adult group compared to younger ones.

Conclusion

Our study provides a whole metabolic profile of serum and urine characteristics of young and adult canines, identifying several metabolites that were significantly associated with age change, which provides theoretical support for the nutrition-related research and age-related homeostasis maintenance in dogs.

Vector-borne disease and its relationship to hematologic abnormalities and microalbuminuria in retired racing and show-bred greyhounds

Background

Reference intervals for platelets and white blood cell (WBCs) counts are lower in greyhounds than other breeds. Proteinuria is common. Vector‐borne diseases (VBD) cause thrombocytopenia, leukopenia, and proteinuria. Racing greyhounds are commonly exposed to vectors that carry multiple organisms capable of chronically infecting clinically healthy dogs.

Hypothesis/Objectives

Vector‐borne disease prevalence is higher in retired racing greyhounds than in show‐bred greyhounds. Occult infection contributes to breed‐related laboratory abnormalities.

Animals

Thirty National Greyhound Association (NGA) retired racing and 28 American Kennel Club (AKC) show‐bred greyhounds.

Methods

Peripheral blood was tested for Anaplasma, Babesia, Bartonella, Ehrlichia, hemotropic Mycoplasma, and Rickettsia species using PCR. Antibodies to Anaplasma, Babesia, Bartonella, Ehrlichia, and Rickettsia species and Borrelia burgdorferi were detected using immunofluorescence and ELISA assays. Complete blood counts, semiquantitative platelet estimates, and microalbuminuria concentration were determined.

Results

Seven of 30 NGA and 1/28 AKC greyhounds tested positive for ≥1 VBD (P = .05). More positive tests were documented in NGA (10/630) than in AKC dogs (1/588; P = .02). Exposure to Bartonella species (3/30), Babesia vogeli (2/30), Ehrlichia canis (1/30), and infection with Mycoplasma hemocanis (3/30) occurred in NGA dogs. Platelet counts or estimates were >170 000/μL. White blood cell counts <4000/μL (4/28 AKC; 5/30 NGA, P > .99; 1/8 VBD positive; 8/51 VBD negative, P = .99) and microalbuminuria (10/21 AKC; 5/26 NGA, P = .06; 1/8 VBD positive; 14/25 VBD negative, P = .41) were not associated with VBD.

Conclusions and Clinical Importance

The prevalence of thrombocytopenia and B. vogeli exposure was lower than previously documented. Larger studies investigating the health impact of multiple VBD organisms are warranted.

Obstructive struvite ureterolithiasis in 4-month-old intact male Bernese mountain dog

A 4-month-old, 7 kg, intact male, Bernese mountain dog was presented for obstructive struvite ureterolithiasis. Multiple urethroliths, ureteroliths, and urocystoliths were present. Based on an abdominal ultrasound, there was severe left hydronephrosis and hydroureter from distal ureterolith obstruction, just proximal to the vesicoureteral junction. The dog was not azotemic. Successful treatment was accomplished via ventral cystotomy. Bladder wall culture revealed a methicillin-resistant Staphylococcus spp. No predisposing cause was identified. There are no known genetic predispositions in Bernese mountain dogs for struvite urolithiasis. The urinary tract infection resolved with surgical retrieval of the uroliths and antibiotic treatment. The dog remained clinically normal after the cystotomy but developed a subclinical urinary tract infection 4 mo post-operatively. Key clinical message: Urolithiasis is rare in pediatric veterinary patients. To the authors' knowledge, this is the first report of obstructive ureterolithiasis in a puppy. There is no known genetic predisposition for urolithiasis in Bernese mountain dogs.

Age, breed, sex and diet influence serum metabolite profiles of 2000 pet dogs

As an individual's metabolism reflects health and disease states well, metabolomics holds a vast potential in biomedical applications. However, normal physiological factors, such as age, can also influence metabolism, challenging the establishment of disease-specific metabolic aberrations. Here, we examined how physiological and diet-related factors drive variance in the metabolism of healthy pet dogs. We analysed 2068 serum samples using a canine nuclear magnetic resonance (NMR) spectroscopy-based metabolomics platform. With generalized linear models, we discovered that age, breed, sex, sterilization, diet type and fasting time significantly affected the canine metabolite profiles. Especially, breed and age caused considerable variation in the metabolite concentrations, and breeds with very different body conformations systematically differed in several lipid measurands. Our results enhance the understanding how normal physiological factors influence canine metabolism, aid accurate interpretation of the NMR results, and suggest the NMR platform might be applied in identifying aberrations in nutrient absorption and metabolism.

Age, breed, sex and diet influence serum metabolite profiles of 2000 pet dogs

As an individual's metabolism reflects health and disease states well, metabolomics holds a vast potential in biomedical applications. However, normal physiological factors, such as age, can also influence metabolism, challenging the establishment of disease-specific metabolic aberrations. Here, we examined how physiological and diet-related factors drive variance in the metabolism of healthy pet dogs. We analysed 2068 serum samples using a canine nuclear magnetic resonance (NMR) spectroscopy-based metabolomics platform. With generalized linear models, we discovered that age, breed, sex, sterilization, diet type and fasting time significantly affected the canine metabolite profiles. Especially, breed and age caused considerable variation in the metabolite concentrations, and breeds with very different body conformations systematically differed in several lipid measurands. Our results enhance the understanding how normal physiological factors influence canine metabolism, aid accurate interpretation of the NMR results, and suggest the NMR platform might be applied in identifying aberrations in nutrient absorption and metabolism.

Effect of age, sex, and body size on the blood biochemistry and physiological constants of dogs from 4 wk. to > 52 wk. of age

BACKGROUND

Blood biochemistry and reference intervals help to differentiate between healthy and ill dogs as well as to provide information for the prognosis, evaluation, and monitoring; however, these intervals are often obtained from adult animals. It is essential to understand that puppies and adults are physiologically different, which justifies the need to obtain age-specific biochemical reference intervals. The aim of this research was to assess the potential effect of age, sex, body size, and their interaction on routine biochemical analytes and physiological constants (body temperature, heart rate, and respiratory rate). To carry out the research, we selected 197 healthy dogs of both sexes and different body sizes (small, medium and large) classified by age: group I (4-8 wk), group II (9-24 wk), group III (25-52 wk), and group IV (> 52 wk). The biochemical analysis included the measurement of the enzymatic activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), and the concentrations of cholesterol, triglycerides, total proteins, albumin, globulins, glucose, urea, and creatinine. Statistical analyses used analysis of variance (ANOVA) and a general linear model (GLM), which allows the comparison of multiple factors at two or more levels (p < 0.05).

RESULTS

The results of this study showed that ALT, total protein, albumin, globulin, urea, creatinine, and body temperature levels were lower in puppies than in adult dogs of group IV (p < 0.05), while the enzymatic activity of ALP, LDH, glucose concentration, and heart rate were higher. Whereas sex, body size and the interaction did not show a significant effect (p > 0.05).

CONCLUSIONS

Some biochemical components are influenced by age. For this reason, this manuscript contributes with additional data for the clinical interpretation of blood biochemical results in puppies.

Serum Symmetric Dimethylarginine Concentration in Greyhound Pups and Adults

Greyhounds have developed numerous physiologic and hematologic adaptations specific to the breed. Adult Greyhounds have significantly higher serum creatinine (sCr) concentrations than non-Greyhound dogs; this is primarily attributed to their large muscle mass. Adult Greyhounds also have significantly higher symmetric dimethylarginine (SDMA) concentrations than non-Greyhound dogs. In this study we evaluated serum SDMA and sCr concentrations in 48 Greyhound pups from 11 litters, with no exposure to racing, in order to determine if the higher SDMA or sCr concentration in adults is a breed-related trait or is associated with extra-physiological causes (e.g., racing environment, drug administration, etc.). The distribution of SDMA concentration for all the pups (mean: 0.70 µmol/L; 95% CI: 0.70-0.74 µmol/L) was not statistically different from that found in a group of 183 adult Greyhounds; whereas, distribution of sCr concentration in the pups (mean: 76.9 µmol/L; 95% CI: 70.7-83.1 µmol/L) was significantly different than that observed in adult Greyhounds, suggesting that the 2 samples were drawn from different populations. This study provides evidence to support that the higher serum SDMA concentration in Greyhounds is a breed-related trait.

Age-dependent variations in haematological and serum biochemical parameters of domestic pigeons (Columba livia domestica)

In this study, the age-dependent variations in haematological and serum biochemical parameters of domestic pigeons were evaluated. Sixty apparently healthy domestic pigeons comprising 30 young (2–7 weeks of age) and 30 adult (>7 weeks of age) were sampled from local breeders. Blood was collected from each bird via brachial venipuncture and divided into 2 parts; one part dispensed into labeled tubes containing ethylenediaminetetraacetic acid as anticoagulant was processed for haematological analyses. The other part was dispensed into labeled plain tubes, serum harvested and processed for serum biochemical analyses. Results revealed overall packed cells volume (PCV), haemoglobin concentration (HGB) and red blood cells (RBC) of 42.97 ± 4.53%, 13.15 ± 1.82 g/dL and 3.63 ± 0.50 × 10¹²/L respectively. All haematological parameters except mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) and lymphocyte count showed statistical (p < 0.05) differences between young and adult pigeons. Values recorded for serum total protein, albumin, globulin, serum/albumin ratio, urea, creatinine and urea/creatinine ratio were 4.32 ± 0.74 g/dL, 2.07 ± 0.30 g/dL, 2.25 ± 0.74 g/dL, 1.04 ± 0.43, 0.48 ± 0.33 mg/dL, 0.75 ± 0.52 mg/dL and 0.73 ± 0.51 respectively. Serum urea and creatinine concentrations were significantly (p < 0.05) higher in adult (0.62 ± 0.40; 1.04 ± 0.60 mg/dL) compared to young (0.34 ± 0.13; 0.47 ± 0.15 mg/dL) pigeons. This study therefore demonstrated age-dependent variations in haematological and serum biochemical parameters of domestic pigeons.

Osteogenesis Imperfecta in Two Finnish Lapphund Puppies

Two 8-week-old Finnish Lapphund dogs presented with pain on manipulation, abnormal long bone conformation, retrognathism, and stunted growth compared to their litter mates. Multiple long bone fractures were evident on radiographs. Clinical pathology showed an atypically normal serum alkaline phosphatase activity for dogs this age. Due to poor quality of life, the dogs were humanely euthanized and subjected to a complete necropsy. On necropsy, all bones were soft and easily broken. Histologic examination revealed that the secondary spongiosa was diminished with abnormal bony trabeculae embedded in abundant loose vascular stroma. No Haversian canals were observed and the cortices contained abundant woven bone separated by fibrovascular tissue consistent with the diagnosis of osteogenesis imperfecta (OI). Inbreeding of the sire and female offspring led to a suspicion of recessive inheritance and the particular genetic collagen disorder remains to be identified in this breed.

Biliary Dilation: An Unusual Presentation of Histoplasma capsulatum in a Dog

A 4 mo old intact male Labrador retriever was referred to the authors’ institution for a 3 wk history of weight loss and progressive abdominal distension. Thoracic radiographs revealed sternal lymphadenopathy and a diffuse unstructured interstitial and bronchial pulmonary pattern. An abdominal ultrasound revealed multifocal lymphadenopathy, hepatosplenomegaly, and biliary duct dilation. Fine-needle aspirates of the spleen and liver revealed Histoplasma capsulatum organisms. Antifungal therapy was initiated with itraconazole and terbinafine. Repeat ultrasound examinations revealed resolving hepatosplenomegaly and resolving cystic duct dilation. Ultrasonographic findings mirrored a decrease in urine H capsulatum antigen levels. Histoplasmosis should be considered as a differential for unexplained biliary duct dilation or obstruction in dogs. Dogs with disseminated histoplasmosis should be monitored for this potential complication.

Clinical and Immunological Metrics During Pediatric Rhesus Macaque Development

Background: Clinical measurements commonly used to evaluate overall health of laboratory animals including complete blood count, serum chemistry, weight, and immunophenotyping, differ with respect to age, development, and environment. This report provides comprehensive clinical and immunological reference ranges for pediatric rhesus macaques over the first year of life. Methods: We collected and analyzed blood samples from 151 healthy rhesus macaques, aged 0-55 weeks, and compared mother-reared infants to two categories of nursery-reared infants; those on an active research protocol and those under derivation for the expanded specific-pathogen-free breeding colony. Hematology was performed on EDTA-anticoagulated blood using a Sysmex XT2000i, and serum clinical chemistry was performed using the Beckman AU480 chemistry analyzer. Immunophenotyping of whole blood was performed with immunofluorescence staining and subsequent flow cytometric analysis on a BD LSRFortessa. Plasma cytokine analysis was performed using a Millipore multiplex Luminex assay. Results: For hematological and chemistry measurements, pediatric reference ranges deviate largely from adults. Comparison of mother-reared and nursery-reared animals revealed that large differences depend on rearing conditions and diet. Significant differences found between two nursery-reared cohorts (research and colony animals) indicate large influences of experimental factors and anesthetic events on these parameters. Immune cells and cytokine responses presented with distinct patterns for infants depending on age, birth location, and rearing conditions. Conclusions: Our results illustrate how the immune system changed over time and that there was variability among pediatric age groups. Reference ranges of results reported here will support interpretations for how infection and treatment may skew common immune correlates used for assessment of pathology or protection in research studies as well as help veterinarians in the clinical care of infant non-human primates. We highlighted the importance of using age-specific reference comparisons for pediatric studies and reiterated the utility of rhesus macaques as a model for human studies. Given the rapid transformation that occurs in multiple tissue compartments after birth and cumulative exposures to antigens as individuals grow, a better understanding of immunological development and how this relates to timing of infection or vaccination will support optimal experimental designs for developing vaccines and treatment interventions.

The association between serial point-of-care test results and hospitalization time in canine parvovirus infection (2003-2015)

The objectives of this study were to describe serial point-of-care test results in dogs infected with canine parvovirus (CPV), highlight clinicopathologic abnormalities at various timepoints, and investigate their association with the duration of hospitalization. Two-hundred and four dogs positive for CPV at the Western College of Veterinary Medicine between 2003 and 2015 were included. Data were recorded pertaining to emergency panel and venous blood gas tests at presentation, and every 12 hours thereafter (+/- 4 hours) for the first 72 hours of hospitalization. Common persistent abnormalities included hypoproteinemia, acidosis, hyponatremia, hypochloremia, hyperkalemia, and hyperbicarbonatemia. Ionized hypocalcemia was associated with a longer duration of hospitalization and mild hyperkalemia was associated with a shorter duration of hospitalization (P < 0.05). This study suggests that the use of point-of-care tests for in-hospital monitoring may provide insight into CPV case complexity and predict total hospitalization times.

Changes in saliva of dogs with canine leishmaniosis: A proteomic approach

In the present study, a quantitative proteomic approach to study changes in saliva proteins associated with canine leishmaniosis (CanL) was performed. For this, canine salivary proteins were analysed and compared between dogs before (T0) and after (T1) experimental infection with Leishmania infantum by high-throughput label-based quantitative LC-MS/MS proteomic approach and bioinformatic analysis of the in silico inferred interactome protein network was created from the initial list of differential proteins. More than 2000 proteins were identified, and of the 90 differentially expressed proteins between T0 and T1, 12 were down-regulated with log2 fold change lower than -0.5849, and 19 were up-regulated with log2 fold change greater than 0.5849. This study provides evidence of changes in salivary proteome that can occur in canine leishmaniosis and revealed biological pathways in saliva modulated in canine leishmaniosis with potential for further targeted research.

Demography and welfare status of free-roaming dogs in Yangmingshan National Park, Taiwan

Free-roaming dogs (Canis familiaris) cause threats to native wildlife and public health and raise concerns for their welfare. Understanding the demography of free-roaming dog populations is essential for developing an effective management plan. An evaluation of their welfare status would be beneficial to earn public support for the management plan. In this study, we estimated the population size, survivorship, and health of a free-roaming dog population in Yangmingshan National Park (YMSNP), Taiwan, during 2016-2018. YMSNP is a rural area with human settlements but also a protected area of conservation concern. We identified 191, 176, 216 individuals at our sampling sites in 2016, 2017, and 2018, respectively. Using a photographic capture-recapture method and extrapolation, we estimated that there were 786-979 dogs in the park during this 3-year period. The annual apparent survival rate of identified dogs was 16.7% for 2016-2017 and 23.9% for 2017-2018. The dogs had a high rate of lameness and dermatosis of 5.1-8.8% and 14.2-18.1%, respectively. Thirty-five blood samples showed that 34.3% of the dogs were anemic, 37.1% showed abnormal white blood cell counts, and 68.6% exhibited abnormal platelet counts. These results suggested that the dogs were at high density with low survivorship and in poor health, and new individuals entered the population continuously. Interventions to manage this dog population and to improve their welfare must be carried out. Our study provides an example for monitoring and managing a free-roaming dog population in a rural, conservation area in Southeast Asia.

A homozygous missense variant in the alkaline phosphatase gene ALPL is associated with a severe form of canine hypophosphatasia

Inherited skeletal disorders affect both humans and animals. In the current study, we have performed series of clinical, pathological and genetic examinations to characterize a previously unreported skeletal disease in the Karelian Bear Dog (KBD) breed. The disease was recognized in seven KBD puppies with a variable presentation of skeletal hypomineralization, growth retardation, seizures and movement difficulties. Exome sequencing of one affected dog revealed a homozygous missense variant (c.1301T > G; p.V434G) in the tissue non-specific alkaline phosphatase gene, ALPL. The identified recessive variant showed full segregation with the disease in a cohort of 509 KBDs with a carrier frequency of 0.17 and was absent from 303 dogs from control breeds. In humans, recessive and dominant ALPL mutations cause hypophosphatasia (HPP), a metabolic bone disease with highly heterogeneous clinical manifestations, ranging from lethal perinatal hypomineralization to a relatively mild dental disease. Our study reports the first naturally occurring HPP in animals, resembling the human infantile form. The canine HPP model may serve as a preclinical model while a genetic test will assist in breeding programs.

Effects of low phosphorus intake on serum calcium, phosphorus, alkaline phosphatase activity and parathyroid hormone in growing dogs

A sufficient and balanced supply of calcium and phosphorus is important mainly for the skeletal health of dogs, especially during growth. Numerous reports and research results are quoted, which focus mainly on the effects of both deficient or excessive calcium supplies. The important role that phosphorus plays in the disruption to skeletal development is also explored. The aims of this study were to evaluate the effects of a low phosphorus supply on selected serum parameters of calcium and phosphorus metabolism in both medium and large breed growing dogs, alongside the effects on the apparent digestibility and retention of these minerals as well as the musculoskeletal development, which were published before. Beagle and Foxhound-crossbred puppies (n = 53) between the age of 6 and 24 weeks were either fed a balanced (control) or a low phosphorus diet, the latter one providing about one-third of P amount fed to the control group. In regular intervals, blood samples were obtained to measure serum levels of phosphorus, calcium, alkaline phosphatase activity (ALP) and parathyroid hormone (PTH). Functional Additive Mixed Models were used to analyse these serum concentrations per group and per diet. In the puppies being fed the low phosphorus diet, a distinct decline of serum phosphate concentration was detected with a more pronounced and prolonged effect in the smaller Beagles. At the same time, serum calcium concentration altered in the opposite direction, implying that the product of calcium multiplied by phosphorus was regulated more closely than the calcium to phosphorus ratio. The PTH concentrations were reduced and ALP activity increased at certain time points during the low phosphorus feeding compared to the puppies being fed the control diet. In the latter group, an effect of time or maturation could be demonstrated in relation to the serum phosphate concentration.

Systemic inflammation in dogs with advanced-stage heart failure

BACKGROUND

Although human studies have shown that inflammation plays a role in the development of congestive heart failure, scarce information exists on white blood cell count (WBC) and differential cell counts in various stages of heart failure in man and dogs. A few studies demonstrated increased concentrations of C-reactive protein (CRP), a major acute-phase protein, in cardiac diseases in dogs. Our research aimed to investigate whether CRP concentration, WBC and neutrophil count (NEUT), as markers of systemic inflammation, are elevated in canine cardiovascular patients. We also aimed to find out whether there is an association between CRP concentration and WBC and NEUT, as well as associations between these inflammatory markers and selected echocardiographic parameters. Sixty-two client-owned canine cardiac patients and 12 healthy dogs were included in the study. The patients were classified into International Small Animal Cardiac Health Council classes (ISACHC I-III). The serum CRP concentration was determined using a canine CRP test kit. WBC and NEUT were determined using an automated hematology analyzer.

RESULTS

Significantly higher serum CRP concentration, WBC and NEUT were found in the decompensated stage of heart failure (ISACHC III) compared with healthy dogs and with patients in ISACHC group II and ISACHC group I. Serum CRP concentration significantly positively correlated with WBC (r = 0.65, P < 0.001) and NEUT (r = 0.58, P = 0.002) in the ISACHC III group, while no significant correlations were found in the ISACHC I and II groups. A significant negative correlation between serum CRP concentration and the left ventricular ejection fraction (r = - 0.49, P = 0.046) and a significant positive correlation between CRP and the E wave velocity of the mitral valve inflow (r = 0.52, P = 0.046) were found in the ISACHC III group.

CONCLUSIONS

The CRP concentration, WBC and NEUT were significantly increased in advanced-stage heart failure patients in comparison with compensated patients and healthy dogs, which indicate the presence of systemic inflammation. However, normal CRP concentration and normal WBC and NEUT can also be present in heart failure.