Agronomic characterization of diploid hybrid families derived from crosses between haploids of the common potato and three wild Argentinian tuber-bearing species

Five diploid hybrid families derived from crosses between haploids of three Argentinian cultivars and three diploid wild species,Solanum gourlayi, S. chacoense andS. spegazzinii, were evaluated in a field experiment in Balcarce. All plants were androsterile and, thus, could not be screened for 2n pollen production. Data on agronomic tuber traits were statistically analyzed. Differences among families were non-significant for tuber number/plant, but were significant for tuber weight/plant and dry matter content (with values above 21.0% in two of them). The relative frequencies of tubers in the categories established for size, skin texture, and eye depth were family dependent, but they were familiy independent in the categories established for tuber shape and skin color. Great morphological variability was detected for all the traits studied, and plants with high yield and high dry matter content were identified. These families can be used as sources of germplasm in breeding and to explore heterotic responses in 2x × 4x crosses, given the capacity of some plants to produce 2n eggs, as found in a related investigation.     

Reproducible infection model for Clostridium perfringens in broiler chickens

Experiments were carried out to establish an infection and disease model for Clostridium perfringens in broiler chickens. Previous experiments had failed to induce disease and only a transient colonization with challenge strains had been obtained. In the present study, two series of experiments were conducted, each involving four groups of chickens with each group kept in separate isolators. A coccidial vaccine given at 10 times the prescribed dosage was used to promote the development of necrotic enteritis. In the first experiment, cultures of C. perfringens were mixed with the feed at day 9, 10, 11, and 12, and the coccidial vaccine was given at day 10, whereas in the second experiment, C. perfringens cultures were mixed with the feed at day 17, 18, 19, and 20, and the coccidial vaccine was given at day 18. Chickens were examined at day 9, 11, 12, and 15 (Experiment 1), and at day 17, 18, 20, and 24 (Experiment 2). There was no mortality in any of the groups; however, chickens in the groups receiving both coccidial vaccine and C. peifringens developed the subclinical form of necrotic enteritis, demonstrated by focal necroses in the small intestine, whereas chickens in control groups or groups receiving only coccidial vaccine or only C. perfringens cultures developed no necroses. The results underline the importance of predisposing factors in the development of necrotic enteritis.     

Epidemiological Analysis of Leptospira spp. Infection in Equids from the Brejo Paraibano Microregion of Brazil

Leptospirosis is a zoonotic disease that occurs in humans and several animal species, including cattle, pigs, and horses, and it has a worldwide distribution. In equids, leptospirosis manifests through recurrent uveitis and abortion and other reproductive disorders. The objective of the present study was to investigate the epidemiological situation of Leptospira spp. infection in equids from the Brejo Paraibano microregion in the northeast of Brazil, that is, to assess the prevalence of and identify the major risk factors for infection. For this purpose, blood samples were taken from 257 equids (204 horses, 46 mules, and 7 donkeys), and a microscopic agglutination test (MAT) was used as serological analysis, with 24 serovars of Leptospira spp. as antigens. Antibodies were observed in 16.2% of horses, 13.0% of mules, and 28.6% of donkeys. Animals between the ages of 2.5 and 11 years had a risk of infection 0.4 times lower than those younger than 2.5 years old (odds ratio, 0.4; 95% confidence interval, 0.18-0.90). Further studies are needed to identify potential wild reservoirs and the main routes of infections.     

Validation of a human immunoturbidimetric assay to measure canine albumin in urine and cerebrospinal fluid.

The aim of this study was to validate an automated immunoturbidimetric assay used to quantify human albumin in urine and to accurately measure canine albumin concentrations in both urine and cerebrospinal fluid. The partial homology existing between human and canine albumin limited the accuracy of the human assays in measuring canine albumin without method modifications. Thus, the assay was modified by calibrating the analyzer with calibrators made in the laboratory containing known concentrations of canine albumin. To prepare the set of calibrators, the albumin concentration of pooled sera of healthy dogs was assessed in 5 replicates using the BromocresolGreen assay. Pooled samples were aliquoted and serially diluted to obtain the expected concentrations of albumin (0.5, 1, 5, 13, and 30 mg/dl) for establishing the canine calibration curve. Thereafter, the performance was assessed by analyzing canine urine and CSF The modified assay accurately quantified canine albumin in both specimens, as indicated by the following. Intra- and interassay variability was 0.92% and 2.74%, respectively; recovery was 99.66% and 99.07% in urine and 105.02% in CSF No interference was detected when hemolysate and glucose were added to urine. The test was linear within the verified range (0-225 mg/dl). These results demonstrate that the modified human albumin immunoturbidimetric assay can be a useful tool in the veterinary diagnostic laboratory. It is accurate and tends itself to automatization on chemistry analyzers.     

Supplementation of L‐glycine and L‐glutamate to Japanese quails from 01 to 36 days of age using the ideal protein concept

Experiment I: T_1‐1 = basal diet with 25% crude protein (CP) + limiting amino acids (LA); T_1‐2 = 20% CP + LA; T_1‐3 = 20% CP + LA + L‐glycine; T_1‐4 = 20% CP + LA + L‐glutamate; T_1‐5 = 20% CP + LA + L‐glycine + L‐glutamate. Experiment II: T_2‐1 = basal diet with 22% CP + LA; T_2‐2 = 20% CP + LA; T_2‐3 = 17.6% CP + LA + L‐glycine; T_2‐4 = 17.6% CP + LA + L‐glutamate; T_2‐5 = 17.6% CP + LA + L‐glycine + L‐glutamate. The reduction of dietary protein based on the concept of ideal protein decreases nitrogen excretion in quails when L‐glycine is added to the diets. Quails fed diets supplemented with L‐glutamate as the non‐specific nitrogen source equivalent to the nitrogen level of the control diet had increased nitrogen excretion. However, quails had reduced nitrogen excretion in both experiments when L‐glycine was added to diets with L‐glutamate. Carcass fat was increased by reducing dietary protein, but fat deposition was reduced by adding L‐glutamate and L‐glycine, or both. The dietary addition of L‐glutamate and L‐glycine in quails based on the ideal protein concept is not necessary (Exp. I). Although the total nitrogen, electrolytic balance and glycine level were adjusted in diets, quails had decreased performance. Therefore, other hypotheses besides protein reduction need to be studied (Exp. II). Protein reduction with supplementation of only limiting essential amino acids does not affect quail performance. Dietary addition of L‐glycine reduces nitrogen excretion.     

A modelling approach to infer the effects of wind farms on landscape connectivity for bats

Little is known about the potentially disrupting effects of wind farms on the habitat connectivity of flying vertebrates at the landscape scale. We developed a regional-scale model to assess the wind farm impact on bat migration and commuting routes. The model was implemented for the bat Nyctalus leisleri in a region of central Italy currently undergoing considerable wind farm development. A Species Distribution Model (SDM) for N. leisleri was generated using the MaxEnt algorithm based on 47 presence records (reduced to 19 after the autocorrelation procedure) and 10 environmental variables derived from topographic and land cover maps. We used the SDM to create a map of connectivity using the software UNICOR to identify potential commuting corridors (PCCs). The incidence of each wind farm on bat flight corridors was assessed by overlaying the existing (380) and planned (195) turbine locations onto the PCCs. The SDM was statistically robust (AUC > 0.8). Most of the corridors were concentrated in the western part of the region, which hosts the largest suitable areas for the species; most of the existing (54 %) and planned (72 %) wind farms interfered with important corridors connecting the western and the eastern parts of the region. Our results provide key information on the impact of the wind farm industry on biodiversity on a regional scale. The novel approach adopted, based on SDM and connectivity analysis, could be easily extended to other flying vertebrates and landscapes and constitutes a promising planning tool necessary for harmonizing the development of renewable energy infrastructures with issues of biodiversity conservation.     

Malignant peripheral nerve sheath tumor as a cause of chronic cardiac insufficiency in cattle

Chronic cardiac insufficiency was associated with a malignant peripheral nerve sheath tumor in a cow. An eight-year-old cow developed a progressive condition (over a period of three months) characterized by an enhanced abdominal volume, reluctance to move, a positive jugular pulse, watery diarrhea and death. At necropsy, moderate subcutaneous edema and an enhanced hepatic lobular pattern were observed. A 23x20x11 cm firm, grayish-white mass adhered to and infiltrated the right atrium. Multiple firm, yellowish-white nodules of 0.5 to 12 cm in diameter were diffusely scattered in the epicardium and parietal pericardium. Histologically, the tumor was poorly circumscribed with foci of infiltration of the myocardium. The neoplastic cells had two major histologic patterns, Antoni types A and B. Within occasional foci, pleomorphic cells with an epithelioid appearance were present in addition to multinucleated cells with periodic acid Schiff (PAS)-positive cytoplasmic globules. Foci of cartilaginous and granular differentiations were interspersed among the neoplastic cells. Multiple vessels presented wall hyalinization and tumoral embolus. Large necrotic foci with mineralization and cholesterol clefts were also observed. Immunohistochemically, the tumor was positive for S100 protein, vimentin and neuron-specific enolase labeling.     

A novel strategy for resynchronization of ovulation in Nelore cows using injectable progesterone (P4) and P4 releasing devices to perform two timed inseminations within 22 days

We aimed to evaluate the reproductive performance of Nelore lactating cows submitted to a resynchronization 12 days after timed artificial insemination (TAI) with or without a long‐acting progesterone (P4‐LA) treatment. Nelore cows were submitted to a P4/oestradiol‐based TAI protocol (D0 = insemination). On D12, cows in the control group (n = 184) received a new P4 intravaginal device (0.96 g), whereas cows in the P4‐LA group (n = 192) received the P4 device and 75 mg P4‐LA. Cows identified as non‐pregnant (n = 120) by regression of corpus luteum using colour Doppler ultrasonography on D20 had the P4 device removed and received 500ug of sodium cloprostenol, 1 mg of oestradiol cypionate and 300 IU of eCG and were re‐inseminated on D22. There was no difference (p > 0.10) in the pregnancy rate at D20, D30 and D60 after first TAI between the control (69%, 59.7% and 57%, respectively) and P4‐LA (67%, 55.7%, and 55.2%, respectively) groups. Pregnancy losses were similar between both groups (p > 0.1). For cows submitted to the second TAI, the pre‐ovulatory follicle size did not differ (p > 0.1), but the oestrous detection and pregnancy rates were greater (p < 0.05) in the P4‐LA group (92.2% [59/64] and 60.9% [39/64], respectively) than in controls (75% [42/56] and 44.6% [25/56]). The cumulative pregnancy rate after two TAIs did not differ (p > 0.1) between control (73.3% [135/184]) and P4‐LA (76% [146/192]) groups. The use of P4‐LA at 12 days after TAI potentially increases the pregnancy rates for a new early resynchronization strategy associated with the Doppler imaging for pregnancy diagnosis and results in an alternative to perform two TAIs in 22 days in beef cows.     

Regional application of one-dimensional water flow models for irrigation management

Numerical models for the simulation of soil water processes can be used to evaluate the spatial and temporal variations of crop water requirements; this information can support the irrigation management in a rationale usage of water resources. This latter objective requires the knowledge of spatially distributed input parameters concerning vegetation status, soil hydraulic behaviour and groundwater interaction. This task can be achieved by a conjunctive use of remote sensing techniques, geographical information systems and hydrological simulation models. The present work focuses on the criteria applied for the implementation of a one-dimensional model for water flow in each parcel of an irrigation district in southern Italy having extension of 3000 ha.     

Transformation of Eutypa dieback and esca disease pathogen toxins by antagonistic fungal strains reveals a second detoxification pathway not present in Vitis vinifera

Eutypine, 4-hydroxybenzaldehyde, and 3-phenyllactic acid are some of the phytotoxins produced by the pathogens causing Eutypa dieback and esca disease, two trunk diseases of grapevine (Vitis vinifera). Known biocontrol agents such as Fusarium lateritium and Trichoderma sp. were screened for their ability to consume these toxins. Transformation time courses were performed, and an high-performance liquid chromatography-based method was developed to analyze toxin metabolism and to identify and quantify the converted products. The results show that the aldehyde function of eutypine was reduced to eutypinol, as by V. vinifera cv. Merlot, the cultivar tolerant to Eutypa dieback. We revealed a supplementary detoxification pathway, not known in Merlot, where the aldehyde function was oxidized to eutypinic acid. Moreover, some strains tested could further metabolize the transformation products. Every strain tested could transform 4-hydroxybenzaldehyde to the corresponding alcohol and acid, and these intermediates disappeared totally at the end of the time courses. When biological assays on cells of V. vinifera cv. Chasselas were carried out, the transformation products exhibited a lower toxicity than the toxins. The possibility of selecting new biocontrol agents against trunk diseases of grapevine based on microbial detoxification is discussed.