Thyroid imaging in the dog: current status and future directions

This review describes the advantages and disadvantages of radiography, ultrasonography, and nuclear medicine in the 2 most frequent thyroid pathologies of the dog: acquired primary hypothyroidism and thyroid neoplasia. Ultrasonography and scintigraphy remain the 2 most indicated imaging modalities for these thyroid abnormalities. However, as in human medicine, computed tomography and magnetic resonance imaging also have potential indications. This is especially the case in the evaluation of the extent, local invasiveness, and local or distant metastases of thyroid neoplasia. Based on experience with different imaging modalities in people, we suggest future directions in the imaging of the canine thyroid gland.     

Campylobacter monitoring in German broiler flocks: an explorative time series analysis

Campylobacter, a major zoonotic pathogen, displays seasonality in poultry and in humans. In order to identify temporal patterns in the prevalence of thermophilic Campylobacter spp. in a voluntary monitoring programme in broiler flocks in Germany and in the reported human incidence, time series methods were used. The data originated between May 2004 and June 2007. By the use of seasonal decomposition, autocorrelation and cross-correlation functions, it could be shown that an annual seasonality is present. However, the peak month differs between sample submission, prevalence in broilers and human incidence. Strikingly, the peak in human campylobacterioses preceded the peak in broiler prevalence in Lower Saxony rather than occurring after it. Significant cross-correlations between monthly temperature and prevalence in broilers as well as between human incidence, monthly temperature, rainfall and wind-force were identified. The results highlight the necessity to quantify the transmission of Campylobacter from broiler to humans and to include climatic factors in order to gain further insight into the epidemiology of this zoonotic disease.     

Second round of an interlaboratory comparison of SARS-CoV2 molecular detection assays used by 45 veterinary diagnostic laboratories in the United States

The COVID-19 pandemic presents a continued public health challenge. Veterinary diagnostic laboratories in the United States use RT-rtPCR for animal testing, and many laboratories are certified for testing human samples; hence, ensuring that laboratories have sensitive and specific SARS-CoV2 testing methods is a critical component of the pandemic response. In 2020, the FDA Veterinary Laboratory Investigation and Response Network (Vet-LIRN) led an interlaboratory comparison (ILC1) to help laboratories evaluate their existing RT-rtPCR methods for detecting SARS-CoV2. All participating laboratories were able to detect the viral RNA spiked in buffer and PrimeStore molecular transport medium (MTM). With ILC2, Vet-LIRN extended ILC1 by evaluating analytical sensitivity and specificity of the methods used by participating laboratories to detect 3 SARS-CoV2 variants (B.1; B.1.1.7 [Alpha]; B.1.351 [Beta]) at various copy levels. We analyzed 57 sets of results from 45 laboratories qualitatively and quantitatively according to the principles of ISO 16140-2:2016. More than 95% of analysts detected the SARS-CoV2 RNA in MTM at ≥500 copies for all 3 variants. In addition, for nucleocapsid markers N1 and N2, 81% and 92% of the analysts detected ≤20 copies in the assays, respectively. The analytical specificity of the evaluated methods was >99%. Participating laboratories were able to assess their current method performance, identify possible limitations, and recognize method strengths as part of a continuous learning environment to support the critical need for the reliable diagnosis of COVID-19 in potentially infected animals and humans.     

Inheritance of virulence in Fusarium circinatum,the cause of pitch canker in pines

Wildtype strains of Fusarium circinatum, the causal agent of pitch canker, were crossed to obtain an F₁ generation. Progeny of this cross were tested for virulence by inoculating Pinus radiata seedlings, and were found to induce a wide range of lesion lengths. Two strains from the F₁ generation that induced long lesions (= high virulence) were used as parents to produce an F₂ generation, followed by a second round of selection for high virulence to obtain an F₃ generation. Mean lesion lengths were not significantly different between the three generations (P ≥ 0.196). A parallel set of crosses was performed to select for low virulence by using progeny in the F₁ and F₂ generations that induced short lesions as parents for F₂ and F₃ generations, respectively. In this case, both rounds of selection resulted in a significant reduction in mean lesion length, from 33.8 ± 0.8 mm in the F₁ generation, to 19.7 ± 0.7 and 12.9 ± 0.7 mm in the F₂ and F₃ generations, respectively. Thus it is apparent that F. circinatum retains the genetic capacity for avirulence to pines, which could reflect a lack of strong selection for virulence in nature. Progeny of a cross between high and low virulence parents manifested nearly continuous variation in lesion lengths, consistent with virulence being a quantitatively inherited trait. Based on this cross, broad‐sense heritability (H²) was determined to be 0.74, which suggests that virulence is under strong genetic control.     

Measurement of glycosaminoglycans and keratan sulphate in canine arthropathies

Glycosaminoglycans (gag) and keratan sulphate (ks) were measured in sera and synovial fluids from dogs with either osteoarthritis (oa) or rupture of the cranial cruciate ligament (ccl) and normal dogs. The dogs with oa had higher synovial fluid gag levels (P<0·002) and serum KS (P<0·03) compared to the normal dogs. No significant differences in serum gag were found in either group. In both oa and rupture of the ccl, gag levels were increased in the synovial fluid from the affected joint compared with the clinically normal (inactive) contralateral joint. Neither gag nor ks measurements correlated with serum and synovial fluid antibodies to collagen type II, synovial fluid white cell count or age of dog. It is unlikely that the measurement of these cartilage breakdown products is of value for diagnostic or prognostic use in canine arthropathies.