Initial development of a set of introgression lines from Solanum peruvianum PI 126944 into tomato: exploitation of resistance to viruses

Resistance to Tomato yellow leaf curl virus (TYLCV) and Tomato spotted wilt virus (TSWV), among other diseases, has been reported in Solanum peruvianum PI 126944. Introgression lines (ILs) from S. peruvianum PI 126944 into the genetic background of cultivated tomato (S. lycopersicum) are being developed. Several generations were derived from three interspecific hybrids previously obtained. A lot of crosses and embryo rescue were required until the third backcross, due to the high degree of incompatibility existing between tomato and PI 126944. Crosses between F₁ plants were made to obtain a pseudo-F₂ generation. The same procedure was followed up to the pseudo-F₆ generation. Additional crosses between plants of different generations were made in order to increase progeny. Of 263 molecular markers tested, 105 were polymorphic between tomato and PI 126944. This set of polymorphic markers consisted of 90 simple sequence repeats (SSR) and 15 cleaved amplified polymorphic sequences (CAPS). The amount of the S. peruvianum genome was reduced in advancing generations and this was coupled in some cases with a reduction of incompatibility. However, the S. peruvianum genome was almost completely represented among the different plants of the most advanced generations. ILs will be basically developed from them. Some of the generations developed were resistant to TYLCV and TSWV.     

Susceptibility of larvae and adults of Monochamus galloprovincialis to entomopathogenic fungi under controlled conditions

Six entomopathogenic fungal isolates were tested under controlled conditions, as biological control agents against Monochamus galloprovincialis (Coleoptera: Cerambycidae) (Olivier), the vector of the pine wood nematode Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) (Steiner and Buhrer). The fungi Beauveria bassiana (Bals.-Criv.) Vuill, Metarhizium anisopliae (Metchnikoff) Sorokin, Metarhizium sp. and Fusarium sp. were tested against larvae and adults of the insect, by comparing two exposure techniques: continuous contact and spraying. Regarding the larvae, only Fusarium sp. and Metarhizium sp. killed more than 40% of the individuals, while B. bassiana and M. anisopliae were found to kill 50% of the adults (LT₅₀) within five days. Exposure to B. bassiana reduced adult longevity by 19 days, when compared to untreated beetles, and had a direct efficacy of 46%. Continuous contact with the fungi proved to be more effective than spraying. A larval disinfection protocol was developed to eliminate other fungal isolates from the wood-collected tested individuals. The implications of the results and possible applications of selected strains as bio-control agents against M. galloprovincialis are discussed.     

Incorporation of dietary nitrogen from fish meal and pea meal (Pisum sativum) in muscle tissue of Pacific white shrimp (Litopenaeus vannamei) fed low protein compound diets

Stable isotope analyses were applied to explore the relative dietary nitrogen contributions from fish meal and pea meal (Pisum sativum) to muscle tissue of Pacific white shrimp postlarvae (141 ± 31 mg) fed low protein diets having different proportions of both ingredients as the sole dietary protein sources. A negative control diet was formulated to contain 100% pea meal and six more isoproteic diets to have decreasing levels of pea meal‐derived nitrogen: 95%, 85%, 70%, 55%, 40% and 0% of the initial level. Growth rates were negatively correlated to dietary pea protein inclusion due to progressive essential amino acid deficiencies (sulphur amino acids, threonine, lysine, histidine). The nitrogen turnover rate significantly increased in muscle tissue of shrimps fed diets having high levels of pea meal; however, contrary to observations from a previous study using soy protein, the relative contributions of dietary nitrogen from pea meal to shrimp muscle tissue were equal or higher than expected contributions established by the dietary formulations. Results highlight the effectiveness of stable isotope analysis in assessing the nutritional contributions of alternative ingredients for aquaculture feeds and the potential suitability of pea as a source of protein (provided the diets are nutritionally balanced).     

Can spleen aspirations be safely used for the parasitological diagnosis of canine visceral leishmaniosis? A study on assymptomatic and polysymptomatic animals

The purpose of this study was to evaluate the safety of spleen aspiration as a sampling technique for the parasitological detection by culture and microscopy of Leishmania (chagasi) infantum. Two hundred and nine domiciled dogs from an endemic area for visceral leishmaniasis in Bahia State, Brazil, were studied. Most dogs (87%) were seropositive for anti-L. chagasi antibodies by ELISA. Clinical signs of disease were recorded and the animals monitored during and after spleen puncture in order to detect possible complications associated with the procedure. From a total of 257 splenic punctures in the 209 animals, only three minor events occurred, with no significant consequence for the animals and no association with risk factors. Leishmania was isolated from 149/180 (83%) seropositive dogs, and from 6/26 (23%) seronegative animals. The procedure did not cause adverse side effects or unnecessary suffering and confirmed the diagnosis in a large percentage of dogs. We conclude that spleen aspiration can be considered an effective and safe procedure for the definitive diagnosis of canine visceral leishmaniosis.     

Integration of socio-economic and environmental variables for modelling long-term fire danger in Southern Europe

In Mediterranean forests fire danger assessment is of crucial importance for any fire prevention policy, both at the local and global scale. The objective of this study is to model large scale structural forest fire danger in Southern Europe. This was done through the identification of those physiographic, socioeconomic and environmental factors that best explain fire occurrence in this region. The modeling process consisted of a multi-step analysis based on multiple regression techniques. In this work, a balance is reached between the objectivity of mechanical methods, and the thoroughness entailed by an exhaustive selection of the variables. Due to the different availability of input data, two different fire danger models were built. One model was derived for Portugal, Spain, France, Italy and Greece, using an initial set of 32 independent variables. A second model was derived for a reduced area (Spain, France and Italy) using these 32 plus another 5 variables. Both models were built using the same methodology, which was based on the search for best intermediate models. The dependent variable used to represent forest fire danger was computed through the annual average of fire occurrence. Statistically, both models performed satisfactorily. The final fits for the first and second model yielded R ² values of 0.60 and 0.71, respectively. Given the structural condition of the variables considered, the resulting models can be used to support the design of fire prevention policies on the long-term basis.

Simultaneous detection of porcine circovirus type 2, classical swine fever virus,porcine parvovirus and porcine reproductive and respiratory syndrome virus in pigs by multiplex polymerase chain reaction

Results from a previous study indicated that there are specific arena surface characteristics that are associated with an increased likelihood of lameness in dressage horses. It is important to understand what modifiable arena factors lead to these detrimental surface characteristics. The aim of this study was to describe the use of training surfaces and arenas for United Kingdom dressage horses and to investigate any relationships between arena/surface variables and detrimental surface characteristics. Data from a questionnaire returned by 22.5% of all 11,363 registered members of British Dressage were used for the study. Univariate and multivariable logistic regression models were developed with each of the previously identified surface characteristics as dependent variables. Respondents reported that the majority of arenas were privately owned, sized 20 × 40 m and had a sand and rubber surface. The results indicated that wax-coated and sand and rubber surfaces were associated with less detrimental surface properties than sand, sand and PVC, woodchips or grass. Woodchips were most strongly associated with the detrimental characteristic of slipping, and sand with tripping. The findings indicated that any arena surface should have a base, with limestone the recommended surface, and that crushed concrete was best avoided. This information supported previous studies in racehorses that indicated that surface maintenance is essential, especially when many horses are using an arena daily. Problems were less likely if an arena was privately owned.     

Potential impact of harvesting for the long-term conservation of arboreal marsupials

We used a simulation approach to study the trade-off between forest harvesting and the conservation of arboreal marsupials in managed eucalypt forests of south-eastern New South Wales (Australia). The EDEN gap model is used to predict tree biomass harvested and the resulting shifts in habitat quality (HQ) for arboreal marsupials under different harvesting scenarios. These harvesting scenarios generate a gradient of biomass harvested by varying rotation length and tree retention in different topographic positions. The results suggest that the shape of the curve of reduction of HQ along the harvesting gradient is very sensitive to topographic position and hence to the proportion of topographic units in the landscape. Consequently arboreal marsupial management in logged forests will be region-dependent as each region will have its own pattern of landscape complexity.     

Stereotactic radiosurgery for treatment of osteosarcomas involving the distal portions of the limbs in dogs

Stereotactic radiosurgery (SRS) involves precise delivery of a single large dose of radiation to a designated tumor target. This report describes use of SRS in combination with a frameless stereotactic localization system to treat 11 dogs with appendicular osteosarcomas. Five dogs were treated with SRS alone; 6 were treated with a combination of SRS and chemotherapy. Overall median survival time was 363 days (range, 145 to 763 days), with 6 dogs still alive 90, 142, 234, 367, 633, and 763 days after SRS. Limb function was good or excellent in all 6 dogs that were still alive. Results in these dogs suggest that SRS may be a viable option for dogs with appendicular osteosarcoma, with the potential to provide long-term local tumor control and improvement in limb function, especially when combined with chemotherapy. Because of the destructive nature of osteosarcoma and limitations of SRS, dogs with tumors that are small and have caused minimal bone destruction would likely be the best candidates for this procedure.     

Evaluation and comparison of the health status of Atlantic bottlenose dolphins from the Indian River Lagoon, Florida, and Charleston, South Carolina

OBJECTIVE: To conduct health assessments and compare outcomes in 2 populations of Atlantic bottlenose dolphins. Design-Repeated cross-sectional study. ANIMALS: 171 Atlantic bottlenose dolphins. PROCEDURES: During June and August of 2003 through 2005, 89 dolphins from the Indian River Lagoon (IRL), Florida, and 82 dolphins from estuarine waters near Charleston, SC, were evaluated. A panel of 5 marine mammal veterinarians classified dolphins as clinically normal, possibly diseased, or definitely diseased on the basis of results of physical and ultrasonographic examinations, hematologic and serum biochemical analyses, and cytologic and microbiologic evaluations of gastric contents and swab specimens. RESULTS: Prevalence of dolphins classified as definitely diseased did not differ significantly between the IRL (32%) and Charleston (20%) sites. Proportions of dolphins classified as possibly diseased also did not differ. Lobomycosis was diagnosed in 9 dolphins from the IRL but in none of the dolphins from Charleston. Proportions of dolphins with orogenital papillomas did not differ significantly between the IRL (12%) and Charleston (7%) sites. From 2003 through 2005, the proportion classified as definitely diseased tripled among dolphins from the Charleston site but did not increase significantly among dolphins from the IRL. Dolphins from the Charleston site were more likely to have leukocytosis, lymphocytosis, and low serum concentrations of total protein and total J-globulins than were dolphins from the IRL. CONCLUSIONS AND CLINICAL RELEVANCE: High prevalences of diseased dolphins were identified at both sites; however, the host or environmental factors that contributed to the various abnormalities detected are unknown.     

Equine Chorionic Gonadotropin (eCG) improves bucks’ semen quality during the nonbreeding season

In most goat breeds, testosterone serum concentration and semen quality decrease during the nonbreeding season. However, bucks reproductive activity may be stimulated with the administration of equine chorionic gonadotropin (eCG). Therefore, the aim of this study was to determine whether the repeated administration of eCG stimulates the reproductive status of bucks during the nonbreeding season. The study was performed with 19 bucks that were assigned to a group that was treated with eCG (GeCG) and an untreated control group (GCon). The GeCG bucks received an initial dose of 800 IU of eCG (Day 0), followed by four doses of 500 IU administered every 5 days beginning on Day 5. Serum testosterone and anti‐eCG antibody concentrations, testicular and seminal traits were determined until Day 60. Testosterone concentration (from Day 3 to 21: p < 0.0001), anti‐eCG titre (from Day 12 to 44: p ≤ 0.01), percentage of motile spermatozoa (Day 6: p = 0.006 and 14: p = 0.001) and of spermatozoa with progressive motility (Day 6: p = 0.01 and 14: p = 0.002) and the percentage of spermatozoa with functional membrane (Day 6: p = 0.02 and 22: p = 0.008) were higher in GeCG than in GCon bucks. Also in frozen‐thawed samples, the percentage of motile spermatozoa tended to be higher in GeCG than that of GCon bucks (p = 0.07). In conclusion, the administration of eCG during the nonbreeding season stimulated the secretion of testosterone and improved fresh and possibly frozen‐thawed semen quality. However, it also resulted in an increase in anti‐eCG antibody titre.