Stray dog population health in Jodhpur, India in the wake of an animal birth control (ABC) program

Our objectives were to (1) estimate the prevalence of various health indices in the stray dog population in Jodhpur, India and (2) determine if there was an association between an animal birth control (ABC) program and the prevalence of these health indices in this population. A prevalence survey of 323 sexually intact stray dogs >3 months caught from the streets of Jodhpur from September to November, 2005 indicated that low body condition score (70%), skin conditions (69%) and tick infestation (68%) were the most common health problems in this population. An observational study of 888 stray dogs on the streets of Jodhpur from March to April, 2006 revealed that sterilized dogs were more likely to have a higher body condition score (BCS) than sexually intact dogs when controlling for age, based on a multinomial regression model. However, sterilized dogs were more likely to have a skin condition than sexually intact dogs, based on a logistic regression model. Our observations of the surgical/kennel facility indicated that an effective tick control program was needed. Additionally, the current parasite control protocol at the kennel/shelter facility was inadequate to treat mange, a contact-transmitted skin disease. This is the first study to evaluate the associations between an ABC program and stray dog health, apart from rabies.     

Effect of temperature on metabolic activity of intact microbial communities: Evidence for altered metabolic pathway activity but not for increased maintenance respiration and reduced carbon use efficiency

We used metabolic tracers and modeling to analyze the response of soil metabolism to a sudden change in temperature from 4 to 20 °C. We hypothesized that intact soil microbial communities would exhibit shifts in pentose phosphate pathway and glycolysis activity in the same way as is regularly observed for individual microorganisms in pure culture. We also hypothesized that increased maintenance respiration at higher temperature would result in greater energy production and reduced carbon use efficiency (CUE). Two hours after temperature increase, respiration increased almost 10-fold. Although all metabolic processes were increased, the relative activity of metabolic processes, biosynthesis, and energy production changed. Pentose phosphate pathway was reduced (17-20%), while activities of specific steps in glycolysis (51%) and Krebs cycle (7-13%) were increased. In contrast, only small but significant changes in biosynthesis (+2%), ATP production (−3%) and CUE (+2%) were observed. In a second experiment, we compared the metabolic responses to temperature increases in soils from high and low elevation. The shift in activity from pentose phosphate pathway to glycolysis with higher temperature was confirmed in both soils, but the responses of Krebs cycle, biosynthesis, ATP production, and CUE were site dependent. Our results indicate that 1) in response to temperature, communities behave biochemically similarly to single species and, 2) our understanding of temperature effects on CUE, energy production and use for maintenance and growth processes is still incomplete.     

Fluorescence Analysis of Natural Organic Matter Fractionated by Ultrafiltration: Contrasting Between Urban-Impacted Water, and Radio-Contaminated Water from a Near-Pristine Site

Aqueous natural organic matter (NOM) impacted by two contrasting human impacts was analyzed using by multiresponse fluorescence, decoupled with the resolution routine PARAFAC. The first site is Chalk River, Ontario, Canada, near a pit formerly used to dispose low-level wastes. The second site is the Grand River in Cambridge, south-central Ontario, which is impacted by urban activities and agriculture. Our analysis included raw water, plus fractions from ultrafiltration and solid-phase extraction (SPE). The fluorescence spectra of the NOM, resolved with PARAFAC, showed three common features: humic-like components, at excitation/emission wavelengths 325?C350/450?C475 nm, fulvic-like components at 325/380?C420 nm and protein-like components, at 275/300 nm. Ultrafiltration revealed that most of the NOM comprised fine material below 5,000 Da cut-off (<4% of the total) in the urban-impacted sites and the clean site at Chalk River, but the colloidal fraction (larger than 5,000 Da) was substantially higher in the contaminated water, with ??18?C26% of the total. The protein-like components in the contaminated Chalk River water were affected by ultrafiltration, but less so in the clean Chalk River sample and the urban-impacted waters. SPE preferentially removed the protein-like component in the contaminated Chalk River water (typically 89?C95% signal decrease), but had a limited effect on humic- and fulvic-like components elsewhere. In conclusion, multiresponse fluorescence provided new information on the NOM quality from two contrasting sites, aided by ultrafiltration and SPE. These results are consistent with the in situ production of NOM in the Chalk River contaminated site, and natural production at the other sites.     

Degradation kinetics and mechanism of antibiotic ceftiofur in recycled water derived from a beef farm

Ceftiofur is a third-generation cephalosporin antibiotic that has been widely used to treat bacterial infections in concentrated animal feeding operations (CAFOs). Land application of CAFO waste may lead to the loading of ceftiofur residues and its metabolites to the environment. To understand the potential contamination of the antibiotic in the environment, the degradation kinetics and mechanisms of ceftiofur in solutions blended with and without the recycled water derived from a beef farm were investigated. The transformation of ceftiofur in aqueous solutions in the presence of the CAFO recycled water was the combined process of hydrolysis and biodegradation. The total degradation rates of ceftiofur at 15 °C, 25 °C, 35 °C, and 45 °C varied from 0.4-2.8×10(-3), 1.4-4.4×10(-3), 6.3-11×10(-3), and 11-17×10(-3) h(-1), respectively, in aqueous solutions blended with 1 to 5% CAFO recycled water. Hydrolysis of ceftiofur increased with incubation temperature from 15 to 45 °C. The biodegradation rates of ceftiofur were also temperature-dependent and increased with the application amounts of the recycled CAFO water. Cef-aldehyde and desfuroylceftiofur (DFC) were identified as the main biodegradation and hydrolysis products, respectively. This result suggests that the primary biodegradation mechanism of ceftiofur was the cleavage of the β-lactam ring, while hydrolytic cleavage occurred at the thioester bond. Unlike DFC and ceftiofur, cef-aldehyde does not contain a β-lactam ring and has less antimicrobial activity, indicating that the biodegradation of ceftiofur in animal wastewater may mitigate the potentially adverse impact of the antibiotic to the environment.     

Endoscopically assisted nasojejunal feeding tube placement: technique and results in five dogs

Interest in noninvasive feeding tube placement in companion animals led to the adaption of a human technique utilizing endoscopy to place nasojejunal feeding tubes. Data from medical records in which nasojejunal feeding tubes were attempted were reviewed. Feeding tubes were attempted and successfully placed in five dogs within a median of 35 min. Feeding tubes remained in place for approximately 7 days. Complications included facial irritation (5/5), sneezing (5/5), fractured facial sutures (4/5), vomiting (3/5), diarrhea (3/5), crimping of feeding tube (3/5), regurgitation (1/5), epistaxis (1/5), clogging of the feeding tube (2/5), and oral migration with premature removal of the feeding tube (1/5). The deployment technique used in this study was found to be cumbersome. Despite minor complications, endoscopy can be used to rapidly and accurately place nasoenteric feeding devices.     

Estimated within-herd prevalence (WHP) of Mycobacterium avium subsp. paratuberculosis in a sample of Minnesota dairy herds using bacterial culture of pooled fecal samples

The objective of this study was to describe the estimated within-herd prevalence (WHP) of Mycobacterium avium subsp. paratuberculosis (Map) in a sample of infected dairy herds in Minnesota (N = 66) using test results from bacterial culture of pooled fecal samples. Fecal samples were collected from up to 100 cows in each herd and were tested using bacterial culture in pools of 5 cows based on age order. The mean herd size was 222 (44 to 1500) milking cows; the cows were predominantly Holstein. Using a frequentist approach, the within-herd mean individual fecal prevalence was 10% [95% confidence interval (CI) = 4% to 16%] assuming 70% test sensitivity and 99.5% test specificity. Using Bayesian methods, the estimated true within-herd individual cow prevalence was 14% (95% CI = 7% to 27%). Within-herd prevalence was higher in larger dairy herds than in herds with fewer cows. As Map is the causative agent of Johne's disease (JD), the results of this study could contribute to the success of a nationwide control program for this disease.