Chao-Chin Chang

Association of increased serum acute-phase protein concentrations with reproductive performance in dairy cows with postpartum metritis.

BACKGROUND It is known that quantification of bovine acute-phase proteins could routinely provide early diagnostic and prognostic information for monitoring herd health status. OBJECTIVE The aim of this study was to test the hypothesis that haptoglobin (Hp) and serum amyloid A (SAA) have the potential for indicating uterine infection, mainly due to subclinical endometritis, which can seriously influence the reproductive performance in dairy cows. METHODS A total of 264 serum samples were collected from 24 Holstein dairy cows at defined intervals from 1 week prepartum to 6 months postpartum. Clinically healthy animals (Group 1, n=6) were compared with 24 animals having acute puerperal metritis (Group 2, n=18) and with concentrations obtained from healthy heifers (baseline values, n=10). The concentrations of serum Hp and SAA were measured using a hemoglobin-binding assay and Western blot analysis, respectively. Reproductive performance was assessed as the number of days open and the conception rate at the end of the study. RESULTS Upper cut-off values for Hp and SAA concentrations in heifers were 130.9 microg/L and 51.9 microg/mL, respectively. Hp concentrations in Group 2 were significantly higher than those in Group 1 at all time points (P<.001). Additionally, among the successfully pregnant animals, the number of days open was significantly higher in 6 cows with Hp >130.9 microg/mL (median=316 days) than in 11 cows with Hp < or =130.9 microg/mL (median=120 days) (P=.0024). CONCLUSIONS Serum Hp and SAA concentrations can be used to recognize uterine infection in postpartum cows. The association between elevated Hp values and number of days open suggests Hp may also be a useful indicator of poor prognosis for reproductive performance.

Evaluation of hormone receptor expression for use in predicting survival of female dogs with malignant mammary gland tumors.

OBJECTIVE To evaluate the prognostic potential of expression of hormone receptors in malignant mammary gland tumors of dogs. Design-Cohort study. ANIMALS 89 female dogs with malignant mammary gland tumors and 24 female dogs with benign mammary gland tumors. PROCEDURES Female dogs with malignant (n = 89 dogs) and benign (24) mammary gland tumors were evaluated to determine the prognostic value of the expression of estrogen receptor (ER)A or the progesterone receptor (PR), as determined by use of immunohistochemical methods. RESULTS In this study, 68 (60.2%) and 88 (77.9%) of the 113 dogs with mammary gland tumors had expression of ERA and PR, respectively. Expression of ERA and PR was detected proportionately more frequently in benign tumors (23/24 [95.8%] and 24/24 [100%], respectively) than in malignant tumors (45/89 [50.6%] and 64/89 [71.9%]). Percentage of tumors with positive results for ERA and PR was significantly higher in tumors < 5 cm in diameter; as clinical stage I, II, or III; and without metastasis to lymph nodes or distant metastasis. However, only PR expression in tumor cells was significantly associated with 1-year survival after surgical removal of the tumor. Moreover, dogs with malignant tumors expressing ERA and PR had a significantly higher survival rate, compared with the rate for dogs with malignant tumors expressing ERA but not PR. CONCLUSIONS AND CLINICAL RELEVANCE These findings strongly suggested that expression of PR could be used as a prognostic factor for survival, especially in female dogs with malignant mammary gland tumors with ERA expression.

Epidemiology of Bartonella Infection in Rodents and Shrews in Taiwan

During the period of August 2002 and November 2004, an epidemiological investigation for Bartonella infection was conducted in small mammals in Taiwan. Using whole blood culture on chocolate agar plates, Bartonella species were successfully isolated from 41.3% of the 310 animals tested. The isolation rate of Bartonella species varied among different animal species, including 52.7% of the 169 Rattus norvegicus, 28.6% of the 126 Sucus murinus, 10% of the 10 Rattus rattus and 66.7% of the three Rattus losea. Bacteremia prevalence also varied with the origin of the animals, as 56.2% of the animals captured on farms, 38.6% of the ones captured at harbour sites and 11.8% of the animals captured from urban areas were bacteremic. Through molecular analysis of the gltA gene and 16S/23S intergenic spacer region, genetic diversity of Bartonella organisms was identified, including strains closely related to Bartonella tribocorum, Bartonella grahamii, Bartonella elizabethae, Bartonella phoceensis and Bartonella rattimassiliensis. Moreover, this is the first report of zoonotic B. elizabethae and B. grahamii identified in R. losea, the lesser rice‐field rat. Various Bartonella species were identified in R. norvegicus, compared to 97.2% of Suncus murinus with unique Bartonella species. By indirect immunofluorescence antibody test, using various rodent Bartonella species as antigens, consistently low percentage of seropositivity implied that small mammals may play a role as competent reservoirs of Bartonella species in Taiwan. Future studies need to be conducted to determine whether these Bartonella species would be responsible for human cases of unknown fever or febrile illness in Taiwan, especially zoonotic B. elizabethae and B. grahamii.

Prognosis of acute kidney injury in dogs using RIFLE (Risk, Injury, Failure, Loss and End-stage renal failure)-like criteria

A retrospective case-series study evaluated the prognosis of 853 dogs with acute kidney injury (AKI) based on the RIFLE (Risk, Injury, Failure, Loss and End-stage renal failure) criteria, derived from human medicine. The 30-day mortality of dogs with AKI in each class was found to be 23.8 per cent (40 of 168) dogs for Risk, 41.0 per cent (107 of 261) dogs for Injury and 78.5 per cent (333 of 424) dogs for Failure. Using the dogs in the Risk class as the reference, the mortality of dogs in either the Injury or Failure class was significantly higher than that of dogs in the Risk class (P<0.05). The longest median survival time was observed in the Risk class (nine days) and the shortest median survival time was observed in the Failure class (three days). Using a multiple logistic regression model, a new score that simultaneously considered RIFLE class, diarrhoea status and serum phosphorus level was calculated to predict prognosis. Evaluation using the area under the receiver-operating characteristic curve (AUROC) indicated that the new scoring method (AUROC 0.80) was a better prognostic indicator than using RIFLE criteria alone (AUROC 0.73).

Prevalence and Antimicrobial Susceptibility of Salmonellae Isolates from Reptiles in Taiwan

Pets, including reptiles, have been shown to be a source of Salmonella infection in humans. Due to increasing popularity and variety of exotic reptiles as pets in recent years, more human clinical cases of reptile-associated Salmonella infection have been identified. However, limited information is available with regard to serotypes in different reptiles (turtles, snakes, and lizards) and antimicrobial resistance of Salmonella in pet reptiles. The current study was thus conducted to determine the prevalence of Salmonella colonization in pet reptiles. Salmonella organisms were isolated from 30.9% of 476 reptiles investigated. The isolation prevalences were 69.7% (23/33), 62.8% (27/43), and 24.3% (97/400) in snakes, lizards, and turtles, respectively. A total of 44 different Salmonella serovars were identified. Compared with S. Heron, Bredeney, Treforest, and 4,[5],12:i:-, S. Typhimurium isolates were resistant to many antimicrobials tested, and notably 61.1% of the isolates were resistant to cephalothin. The results indicated that raising reptiles as pets could be a possible source of Salmonella infection in humans, particularly zoonotic Salmonella serovars such as S. Typhimurium that may be resistant to antimicrobials.

Prognostic Factors and a Prognostic Index for Cats with Acute Kidney Injury

BACKGROUND The clinical manifestations of acute kidney injury (AKI) range from mild to fatal in cats; however, prognosis factors have been rarely studied. HYPOTHESIS/OBJECTIVES To find the clinical factors significantly correlated with the outcome among cats with AKI and to develop a simple prognostic index. ANIMALS Seventy cats with AKI were recruited. METHODS Demographic and clinicopathological data obtained from 70 cats with AKI were retrospectively collected. Students t-test or Mann-Whitney U-test and Pearson chi-square test or Fishers exact were applied to determine the factors associated with survival in cats with AKI. Using logistic regression, the statistically significant factors associated with prognosis were identified and a new prediction model was generated. RESULTS The overall case fatality rate was 64% (45/70). The results showed that nonsurviving cats had significantly lower levels of PCV, WBC, RBC, LDH and albumin, a lower albumin/globulin ratio, lower blood glucose, and a reduced body temperature, as well as being older. Serum urea and creatinine concentrations were not statistically significant as prognostic factors, but a decrease in these 2 variables in 3 days was significantly related to a reduction in death. A summary prognostic index including body temperature and LDH and albumin concentrations had area under the receiver-operating characteristic curve (AUROC) for predicting death of 0.86 (P < .05) and a cut-off value of 0.82, a sensitivity of 77% and a specificity of 90%. CONCLUSIONS The prognosis in cats with AKI is quite different from that found for human and dogs.

Identification of risk factors of Coxiella burnetii (Q fever) infection in veterinary-associated populations in southern Taiwan.

The first case of Q fever in Taiwan was reported in 1993. The disease is considered to be emerging in Taiwan, but the route of transmission has remained unclear. The annual number of confirmed Q fever cases has been increasing up to more than 100 cases since 2005, comparing with less than 30 before 2003. The purpose of this study was to determine the seroprevalence and risk factors of Coxiella burnetii infection in veterinary‐associated populations in southern Taiwan. A total of 228 serum samples of high risk individuals engaging in veterinary‐related work or animal‐farm work, were collected between March and June in 2007. The study individuals were interviewed by a structured questionnaire designed for Q fever investigation. Serum samples from different animal species were also obtained for Q fever analysis in the same study areas. Serological test was conducted by indirect immunofluorescence antibody assay (IFA). The result demonstrated the overall seroprevalence of Q fever was 26.3% in individuals engaging in veterinary and animal‐related work in southern Taiwan. After multiple logistic regression analysis, goat exposure was significantly associated with seropositivity of Q fever in the study population in southern Taiwan (adjusted odds ratio: 2.62; 95% CI: 1.06–6.46). In addition, the highest seroprevalence (43.8%) of Q fever was identified in goats (P < 0.05). Finally, this study documented that people with prior knowledge of Q fever were less likely to be seropositive for C. burnetii. It was concluded that goat exposure was the most important risk factor associated with C. burnetii infection and appropriate health education could be useful to prevent high risk individuals from the infection in southern Taiwan.

The identification of frequent variations in the fusion protein of canine distemper virus.

Canine distemper (CD) is a highly contagious disease with a worldwide distribution. Genetic diversity in genes encoding the haemagglutinin (H) and fusion (F) virus envelope proteins have been implicated in the increasing incidence of CD. Unlike the H gene, little is known about the genetic variability of the F gene in this virus. In the present study sequence analysis of the complete coding region of the F protein from CD virus isolates from Taiwan were carried out. Phylogenetic analysis demonstrated that the majority of isolates were similar to those found in neighbouring China and Japan, but were genetically distinct from vaccine strains. Remarkable variations were found scattered throughout the pre-peptide region (residues 1-135). The sequence identity of this region between locally sourced strains and between these strains and vaccine strains was 89% and 64 to 67%, respectively. Analysis suggested a novel strain of distant genetic lineage was present in dogs in the geographically isolated city of Hualien.

The reproductive performance of female Formosan sambar deer (Cervus unicolor swinhoei) in semi-domesticated herds.

This study documented the reproductive performance of 210 adult female Formosan sambar deer (FSD, Cervus unicolor swinhoei) from four semi-domesticated deer herds in Taiwan. An extensive analysis of 525 reproductive records from 2000 to 2008, including the conditions of estrus, gestation, and parturition was conducted. The mean+/-S.E.M. lengths of the estrous cycle, gestation, and fawning interval were 18.2+/-0.5d (n=56), 258.6+/-0.3d (n=160), and 369.9+/-2.3d (n=122), respectively. Hand breeding was performed between June and December (n=494), with the majority (93.1%) occurring between July and October (P<0.05). Fawning occurred from February to September (n=318), and most frequently (83.0%) between April and June (P<0.05). Pregnancy rate per mating in FSD hinds was 64.4%. There was a 1.3:1 male-to-female ratio at birth (P<0.05) among 320 fawns, and only two cases of twinning (0.63%). The postnatal mortality rate was 6.6% (21/320), and the mortality rate in fawns before weaning did not exceed 8% on any farm. Fecundity was enhanced by high pregnancy rates and high offspring survival rates. This study provides baseline information on reproductive performance of FSD, which should be valuable to veterinarians and deer industry personnel for management of FSD on farms in subtropical countries.

A comparative study of the interaction of Bartonella henselae strains with human endothelial cells

Bartonella henselae can cause a wide range of clinical outcomes and may lead to severe disease, especially in patients with acquired immunodeficiency syndrome. It is well-known that B. henselae-induced cell proliferation is mediated by anti-apoptotic activity; however, the detailed mechanism is still unclear. In this study, the cellular responses of endothelial cells after infection with four B. henselae strains were compared and protein candidates that may be involved in the interaction between cells and bacteria were determined. The Houston-1 strain elicited the fastest response in terms of stimulating endothelial cell proliferation, and the JK-40 strain had the strongest ability to induce cell proliferation. By Western blot analysis, it was demonstrated that B. henselae-induced cell proliferation involved the mitochondria intrinsic apoptotic pathway. In addition, the adhesion abilities of the U-4 and JK-40 strains were much greater than those of the Houston-1 and JK-47 strains; however, the ability of Houston-1 to invade host cells was high. By two-dimensional gel electrophoresis analysis, it was found that succinyl-CoA synthetase subunit beta, phage-related protein, and ATP synthase subunit alpha might be involved in the invasion process. The expression of superoxide dismutase [Cu-Zn] precursor increased with infection time for all four strains but was significantly higher in the Houston-1 strain, which may increase the competitive advantage of Houston-1 in terms of survival in host cells and render it successful in invading host cells and stimulating cell proliferation. Our data suggest that the interaction of B. henselae and endothelial cells differed between strains, and the results indicated possible candidate proteins that may play a role in the pathogenesis of B. henselae infection.