Calf health from birth to weaning. III. housing and management of calf pneumonia

Calfhood diseases have a major impact on the economic viability of cattle operations. A three part review series has been developed focusing on calf health from birth to weaning. In this paper, the last of the three part series, we review disease prevention and management with particular reference to pneumonia, focusing primarily on the pre-weaned calf. Pneumonia in recently weaned suckler calves is also considered, where the key risk factors are related to the time of weaning. Weaning of the suckler calf is often combined with additional stressors including a change in nutrition, environmental change, transport and painful husbandry procedures (castration, dehorning). The reduction of the cumulative effects of these multiple stressors around the time of weaning together with vaccination programmes (preconditioning) can reduce subsequent morbidity and mortality in the feedlot. In most studies, calves housed individually and calves housed outdoors with shelter, are associated with decreased risk of disease. Even though it poses greater management challenges, successful group housing of calves is possible. Special emphasis should be given to equal age groups and to keeping groups stable once they are formed. The management of pneumonia in calves is reliant on a sound understanding of aetiology, relevant risk factors, and of effective approaches to diagnosis and treatment. Early signs of pneumonia include increased respiratory rate and fever, followed by depression. The single most important factor determining the success of therapy in calves with pneumonia is early onset of treatment, and subsequent adequate duration of treatment. The efficacy and economical viability of vaccination against respiratory disease in calves remains unclear.     

Paraneoplastic thrombocytosis-induced systemic thromboembolism in a cat

A six-year-old cat presented with clinical signs consistent with distal aortic thromboembolism while clinical signs of cardiovascular disease were absent. Diagnostics, including thoracic radiographs, electrocardiography, and echocardiography revealed no cardiovascular anomalies. Thoracic radiographs revealed multifocal pulmonary lesions consistent with neoplasia. Complete blood cell count demonstrated a marked thrombocytosis, leukopenia, and neutropenia. Histopathology of the pulmonary lesions confirmed multiple bronchoalveolar carcinomas. Myelodysplasia with megakaryocytic hyperplasia and ineffective myelopoiesis was noted on bone-marrow histopathology from multiple sites. The absence of other causes suggested a paraneoplastic thrombocytosis. The diagnosis of paraneoplastic thrombocytosis-induced thromboembolism was made due to the lack of underlying cardiac disease and the presence of a marked thrombocytosis. The presence of thrombocytosis and thromboembolism associated with neoplasia is discussed.     

Treatment of a well differentiated pulmonary adenocarcinoma in a cat by pneumonectomy and adjuvant mitoxantrone chemotherapy

Primary lung neoplasia is a rare condition of older cats. This report describes a case of left-sided pulmonary collapse, secondary to pulmonary adenocarcinoma in an 11-year-old cat. Left sided pneumonectomy was performed, and adjuvant chemotherapy with mitoxantrone (Novantrone; Lederle) was administered every 3 to 5 weeks, for 10 doses after surgery. Thirty-four months after surgery, the cat remains well and has no radiographic evidence of pulmonary metastasis.     

Gram-negative bacterial infections of the mammary gland in cows

Naturally acquired gram-negative bacterial intramammary infections (n = 160) were studied in 99 cows over a 2-year period. Escherichia coli, Klebsiella spp, Serratia spp, Enterobacter spp, and unidentified gram-negative bacteria were isolated from 28.8, 39.4, 9.4, 5.0, and 11.2%, respectively, of infected mammary glands. A majority (61%) of intramammary infections were first detected during the nonlactating period. Gram-negative bacteria isolated during the first half of the nonlactating period were predominantly Klebsiella spp, Serratia spp, and Enterobacter spp. Onset of E coli intramammary infections was more prevalent during the second half of the nonlactating period and during the first 7 days of lactation. The majority (59%) of infections were less than 28 days in duration, but Klebsiella spp and Serratia spp infections were of significantly (P less than 0.05) greater duration than infections with E coli. The greatest percentage (47%) of gram-negative bacterial intramammary infections were first detected during the summer.     

Echocardiographic evidence for myocardial failure induced by taurine deficiency in domestic cats.

Dietary taurine-deficiency is a cause of dilated cardiomyopathy (DCM) in cats. While the incidence of clinical cases of feline DCM has markedly decreased since the association between DCM and taurine-deficiency was first recognized, not all cats maintained on taurine-deficient diets develop DCM. The objective was to temporally evaluate left ventricular (LV) function using M-mode echocardiography in 23 cats maintained on a taurine-deficient diet; 20 time-matched, taurine-supplemented cats served as controls. The duration of feeding trials ranged from 6-15 months. No diminution of myocardial function was recorded in a small number of taurine-deficient cats whereas cardiac performance in some taurine-deficient cats diminished to levels characteristic of DCM. Of the taurine-deficient cats, 17 (74%) experienced a greater than 25% reduction in fractional shortening and 21 (91%) had a greater than 25% increase in LV end-systolic short-axis diameter. On average, LV end-systolic short-axis diameter increased by 70% and fractional shortening decreased by 37% in taurine-deficient cats. Mean velocity of circumferential fiber shortening was similarly reduced in taurine-deficient cats. The greatest rate of change in M-mode echocardiographic variables occurred during the first four months on the taurine-deficient diet. Dietary taurine deficiency leads to a spectrum of changes in myocardial function in domestic cats. While DCM is observed in some cats, decreased systolic pump function and increased LV end-systolic short-axis diameter are more consistent findings.     

Hematogenous septic arthritis in the dog: results of five patients treated nonsurgically with antibiotics

This retrospective study evaluates the effectiveness of nonsurgical treatment using antibiotics to treat hematogenous septic arthritis in five dogs. Giant-breed dogs were over-represented, with all dogs <1 year of age. Synovial fluid cultures were positive in all cases, with common bacterial species isolated that included Streptococcus B-haemolytic spp., Pasteurella multocida, and Staphylococcus intermedius. Dogs treated with appropriate duration and selection of antibiotics had clinical resolution with no residual deficits. This report and a previous clinical report demonstrate that hematogenous septic arthritis can be successfully treated nonsurgically with antibiotic therapy.     

Utility of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) to distinguish between congestive heart failure and non-cardiac causes of acute dyspnea in cats

BackgroundCirculating plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration facilitates emergency diagnosis of congestive heart failure (CHF) in people. Its utility to discriminate between dyspneic cats with CHF vs. primary respiratory disease requires further assessment. Our objectives were to determine if NT-proBNP (1) differentiates dyspneic cats with CHF vs. primary respiratory disease; (2) increases with renal insufficiency; (3) correlates with left atrial dimension, radiographic cardiomegaly, and estimated left ventricular filling pressure (E/E_a).MethodsNT-proBNP was measured in 167 dyspneic cats (66 primary respiratory disease, 101 CHF) to evaluate (1) relationship with clinical parameters; (2) ability to distinguish CHF from primary respiratory disease; (3) optimal cut-off values using receiver operating characteristic (ROC) curve analysis.ResultsNT-proBNP (1) was higher (median and inter-quartile [25th–75th] percentile) in CHF (754 pmol/L; 437, 1035 pmol/L) vs. primary respiratory disease (76.5 pmol/L; 24, 180 pmol/L) cohorts (P < 0.001); (2) positively correlated in CHF cats with increased inter-ventricular septal end-diastolic thickness (ρ = 0.266; P = 0.007) and LV free wall thickness (ρ = 0.218; P = 0.027), but not with radiographic heart size, left atrial size, left ventricular dimensions, E/E_a ratio, BUN, creatinine, or thyroxine; (3) distinguished dyspneic CHF cats from primary respiratory disease at 265 pmol/L cut-off value with 90.2% sensitivity, 87.9% specificity, 92% positive predictive value, and 85.3% negative predictive value (area under ROC curve, 0.94).ConclusionsNT-proBNP accurately discriminated CHF from respiratory disease causes of dyspnea.