Comparison on accuracy of different nonlinear models in predicting growth of Podolica bulls

Animal growth does not follow a linear pattern, being explained mathematically by functions that have parameters with biological meaning. These parameters are used to estimate the expected weight of animals at specific ages. Several nonlinear models have been used to describe growth. This study was carried out to estimate the parameters of logistic, Gompertz, Richards and von Bertalanffy growth curve models in a sample of Podolica young bulls to determine the goodness of fit. Animals were weighed every 3 months from birth to 810 days of age. The results indicate that all the growth models used were easily fitted to the observed data with Gompertz and logistic functions presenting less computational difficulty in terms of number of iterations to achieve convergence. Moreover, logistic and Richards equations provided the best overall fit being useful to describe the growth of Podolica bulls. Considering that the literature lacks information on growth curves in Podolica breed, the study of a mathematical model for growth describing the developmental pattern of a specific population within a peculiar environment is a useful tool to improve Podolica breed production.     

Pharmacokinetic and pharmacodynamic evaluations of a 10 mg/kg enrofloxacin intramuscular administration in bearded dragons (Pogona vitticeps): a preliminary assessment

Enrofloxacin (E) is commonly used in veterinary medicine. It is necessary to perform pharmacokinetic/dynamic studies to minimize the selection of resistant mutants of bacteria and extend the efficacy of antimicrobial agents. Eight healthy adult Pogona vitticeps were assigned into two groups of equal size and treated with a single intramuscular injection of E at 10 mg/kg. Blood samples were withdrawn at different scheduled times for each group, and rectal swabs were collected. E and ciprofloxacin (active metabolite) blood concentrations were quantified by an HPLC validated method, while the in vitro antimicrobial susceptibility was evaluated by the Kirby–Bauer disc diffusion susceptibility test. The pharmacokinetic profiles of E gave similar pharmacokinetic parameters irrespective of the collection time schedule. Bacteria isolation showed the presence of both E. coli, Salmonella enterica subspecies enterica and subspecies 3a, Proteus spp., and Pseudomonas spp. The majority of isolated colonies were sensitive to E, but the treatment did not reduce the number of bacteria in faeces. Results suggest that E is able to reach blood concentrations high enough to kill susceptible bacteria (MIC < 0.9 μg/mL), but at the same time does not significantly affect intestinal bacteria.     

Kaolin influences tomato response to salinity: physiological aspects

Environmental stress as salinity can negatively affect the physiology of tomato plants. Conditions leading to a reduction of transpiration can contribute to greater tolerance to salinity. Use of kaolin-based particle film technology (PFT) may be an effective tool to control stomatal conductance and transpiration rate, thus mitigating the detrimental effect of salinity. The present three-year study has investigated the effects of kaolin application on leaf gas exchange, leaf water potential, leaf and canopy temperature of field-grown tomato, irrigated with brackish water by drip method, in southern Italy. Treatments were: (1) three salinity levels of irrigation water (electrical conductivity of water = 0.5, 5 and 10 dS m^?1); (2) tomato plants treated or not with kaolin; and (3) two cultivars in each year. The increase in salinity caused the reduction of leaf water potential, stomatal conductance, net photosynthesis and transpiration rate, and the increase of leaf and canopy temperature. Kaolin has resulted in an improvement of leaf water potential, and the reduction in gas exchange variables in low-salinity conditions. Under high salinity, kaolin was effective in limiting the reductions in net photosynthesis and reducing leaf and canopy temperature. These latter variables were slightly affected by kaolin, in different ways in respect to the saline treatments; while in non-saline conditions were 0.2–0.5°C higher in the kaolin-treated plants, the situation was reversed in more saline treatment. The variation of leaf and canopy temperature shows that kaolin influences the thermal balance mainly for the dual effect of reflection of the incident radiation and partial occlusion of the stomata. Kaolin mitigated detrimental effects of salinity also on yield, contributing to the improvement of income for the farmers. The use of kaolin-based PFT may be an effective tool to alleviate salinity stress in tomato production under arid and semi-arid conditions.     

Seroprevalence for norovirus genogroups GII and GIV in captive non‐human primates

Noroviruses (NoVs) are a major cause of epidemic gastroenteritis in children and adults. Several pieces of evidence suggest that viruses genetically and antigenically closely related to human NoVs might infect animals, raising public health concerns about potential cross‐species transmission. The natural susceptibility of non‐human primates (NPHs) to human NoV infections has already been reported, but a limited amount of data is currently available. In order to start filling this gap, we screened a total of 86 serum samples of seven different species of NPHs housed at the Zoological Garden (Bioparco) of Rome (Italy), collected between 2001 and 2017, using an enzyme‐linked immunosorbent assay (ELISA) based on virus‐like particles (VLPs) of human GII.4 and GIV.1 NoVs. Antibodies specific for both genotypes were detected with an overall prevalence of 32.6%. In detail, IgG antibodies against GII.4 NoVs were found in 18 Japanese macaques (29.0%, 18/62), a mandrill (10.0%, 1/10), a white‐crowned mangabey (16.6%, 1/6) and in an orangutan (33.3%, 1/3). Twelve macaques (19.3%, 12/62), five mandrills (50.0%, 5/10), two chimpanzees (100%, 2/2) and a white‐crowned mangabey (16.6%, 1/6) showed antibodies for GIV.1 NoVs. The findings of this study confirm the natural susceptibility of captive NHPs to GII NoV infections. In addition, IgG antibodies against GIV.1 were detected, suggesting that NHPs are exposed to GIV NoVs or to antigenically related NoV strains.     

Pharmacokinetic profiles of the active metamizole metabolites after four different routes of administration in healthy dogs

Metamizole (MT), an analgesic and antipyretic drug, is rapidly hydrolyzed to the active primary metabolite 4‐methylaminoantipyrine (MAA) and relatively active secondary metabolite 4‐aminoantipyrine (AA). The aim of this study was to assess the pharmacokinetic profiles of MAA and AA after dose of 25 mg/kg MT by intravenous (i.v.), intramuscular (i.m.), oral (p.o.), and rectal (RC) routes in dogs. Six dogs were randomly allocated to an open, single‐dose, four‐treatment, four‐phase, unpaired, crossover study design. Blood was collected at predetermined times within 24 hr, and plasma was analyzed by a validated HPLC‐UV method. Plasma concentrations of MAA and AA after i.v., i.m., p.o., and RC administrations of MT were detectable from 5 (i.v. and i.m.) or 30 (p.o. and RC) min to 24 hr in all dogs. The highest concentrations of MAA were found in the i.v., then i.m., p.o., and RC groups. Plasma concentrations of AA were similar for i.v., i.m., and RC, and the concentrations were approximately double those in the PO groups. The AUC_EV/IV ratio for MAA was 0.75 ± 0.11, 0.59 ± 0.08, and 0.32 ± 0.05, for i.m., p.o., and RC, respectively. The AUC_EV/IV ratio for AA was 1.21 ± 0.33, 2.17 ± 0.62, and 1.08 ± 0.19, for i.m., p.o., and RC, respectively. Although further studies are needed, rectal administration seems to be the least suitable route of administration for MT in the dog.     

Measuring Field Rill Erodibility by a Simplified Method

Many process‐oriented erosion prediction models reproduce rill erosion as affected by site‐specific parameters, as for example, rill erodibility, and thus, their practical application requires the measurement of these parameters or their estimate. The aim of this paper was establishing a method for indirectly measuring field rill erodibility. A simple mathematical approach based on a known soil detachment equation and accounting for the rill erosion dynamic process is applied. Field measurements carried out for seven natural rainfall events occurring at the plots of the Sparacia experimental station, southern Italy, are used for indirectly measuring the rill erodibility of the investigated soil. This method needs only the knowledge of the geometric characteristics of the rills at the end of the erosion event and the event duration. The method was also tested by using the Water Erosion Prediction Project database, and this analysis showed that a reliable value of rill erodibility can be obtained by the proposed Equation 18 . The proposed method has the following advantages: (i) to be applicable at field scale, being more realistic than the laboratory scale because the soil structure is not destroyed, and (ii) to avoid the disadvantages of field experiments such as the cumbersome experimental set‐up and the large volume of water inflow needed. Copyright © 2015 John Wiley & Sons, Ltd.     

Stomach wall evaluation using helical hydro-computed tomography

In helical hydro-computed tomography (helical hydro-CT), water is used as a neutral luminal contrast medium together with intravenous iodine contrast medium for the diagnosis and staging of human gastric neoplasia. We evaluated the feasibility of helical hydro-CT in 11 healthy animals (nine dogs and two cats). Adequate uniform gastric distension was obtained with 30 ml water/kg body weight. Fourteen client-owned dogs and four cats with suspected or diagnosed gastric neoplasia then underwent helical hydro-CT followed by intravenous contrast medium administration. Focal thickening with moderate contrast enhancement was found in 10 dogs and 3 cats. The extent of the lesion was assessed easily in all these patients. Three dogs and one cat had a normal stomach wall. One dog had multifocal thickening of the antrum but no histopathologic diagnosis was made. Helical hydro-CT, followed by intravenous contrast medium administration, is a simple technique for assessing the stomach wall.