Abundance and Frequency of the Asiatic Oak Weevil (Coleoptera: Curculionidae) and Defoliation on American,Chinese, and Hybrid Chestnut (Castanea)

The Asiatic oak weevil, Cyrtepistomus castaneus Roelofs (Coleoptera: Curculionidae), is a nonnative defoliator of trees in the Fagaceae family in the United States but has not been studied on Castanea species in the southern Appalachian Mountains. Planted trees of Castanea dentata (Marsh.) Borkh. (Fagales: Fagaceae), Castanea mollissima Blume (Fagales: Fagaceae), and four hybrid breeding generations were evaluated in 2012 for insect defoliation and C. castaneus abundance and frequency. Defoliation was visually assessed throughout the growing season at two sites in the southern Appalachian Mountains (western North Carolina and eastern Tennessee). C. castaneus abundance and frequency were monitored on trees using beat sheets and emergence was recorded from ground traps. Asiatic oak weevils were more abundant and more frequently collected on American chestnut (Ca. dentata) and its most closely related BC₃F₃ hybrid generation than on the Asian species Ca. mollissima. In most months, C. castaneus colonization of hybrid generations was not significantly different than colonization of parental species. Frequency data for C. castaneus suggested that adults were distributed relatively evenly throughout the study sites rather than in dense clusters. Emergence of C. castaneus was significantly higher under a canopy dominated by Quercus species than under non-Quercus species or open sky. C. castaneus emergence began in May and peaked in late June and early July. These results may be useful for resource managers trying to restore blight-resistant chestnut to the Southern Appalachians while minimizing herbivory by insect pests.     

Changes in submersed aquatic vegetation affect predation risk of a common prey fish Lucania parva (Cyprinodontiformes: Fundulidae) in a spring‐fed coastal river

Abstract Predation risk can impact population dynamics and ecosystem structure. Changes in key habitats, such as shifts between types of submersed aquatic vegetation, may affect predation risks experienced by certain organisms that use vegetation as a predation refuge. Relative predation risks experienced by Lucania parva (Baird & Girard) were assessed among three habitats in a Florida coastal stream using tethering experiments. Relative predation risks were highest in bare substrate, intermediate in a rooted macrophyte, Vallisneria americana Michx, and lowest in filamentous macroalgae. These results suggest that L. parva predation risk may decline following shifts from macrophytes to filamentous macroalgae, potentially leading to increased L. parva population size. These findings counter a widely held perception that such habitat shifts yield exclusively negative faunal effects, and are useful for assessing implications of habitat change and guiding restoration activities.     

Antithrombotic Effect of Enoxaparin in Clinically Healthy Cats: A Venous Stasis Model

Background: Systemic arterial thromboembolic events are a serious complication of cardiac disease in cats.
Objectives: To determine if enoxaparin induces an antithrombotic effect in cats at a dosage of 1 mg/kg SC q12h and if this antithrombotic effect is predicted by anti-Xa activity.
Animals: Fourteen clinically healthy cats were divided into 3 groups: control (4 cats), treated and assessed at 4 hours (5 cats), and treated and assessed at 12 hours (5 cats).
Methods: A venous stasis model was used and the extent of thrombus formation estimated by measuring thrombus weight and accretion of ¹²⁵I-fibrinogen. Plasma anti-Xa activity was measured in treated cats.
Results: There was a significant reduction in thrombus formation in the 4 h group compared with control (median weight, 0.000 versus 0.565 mg/mm, P < .01; median %¹²⁵I-fibrinogen accretion, 0.0 versus 42.0%, P < .01). There was a reduction in thrombus formation in the 12 h group (median weight, 0.006 mg/mm, P = .09; median %¹²⁵I-fibrinogen accretion, 3.83%, P = .09) but this reduction was not significant. The median percent thrombus inhibition for treated cats was 100.0% at 4 hours and 91.4% at 12 hours. Plasma anti-Xa activity was not significantly correlated with thrombus formation.
Conclusions and Clinical Importance: This pilot study demonstrates that enoxaparin, when administered at a dosage of 1 mg/kg SC q12h, produces an antithrombotic effect in a venous statsis model in clinically healthy cats. Furthermore, this study demonstrates that anti-Xa activity is a poor predictor of enoxaparin's antithrombotic effect.     

Dietary Zinc Requirement of Oreochromis aureus and Effects of Dietary Calcium and Phytate on Zinc Bioavailability

Two experiments were conducted to determine the dietary zinc requirement of fingerling blue tilapia ( Oreochromis oureus ) and the effects of dietary calcium and phytate on zinc bioavailability. Purified egg white diets containing graded levels of supplemental zinc were fed to fingerling tilapia in triplicate aquaria for 80 days. No overt signs of zinc deficiency were observed; however, scale and bone zinc concentrations of fish fed the various diets were significantly (P < 0.05) affected and increased linearly as dietary zinc increased until plateauing at 20 mg Zn/kg diet and greater. Based on these data, 20 mg Zn/kg of dry diet was determined to be the minimum dietary zinc requirement of blue tilapia. Purified egg white diets containing 20 mg Zn/kg were also supplemented with 0.5 or 2.0% calcium and 0 or 1.5% phytate in a factorial arrangement to determine the effects of these dietary factors on zinc bioavailability. At this level of supplemental zinc, 1.5% phytate significantly ( P < 0.05) reduced zinc bioavailability as reflected in scale and bone zinc concentrations; whereas, dietary calcium did not affect zinc bioavailability. Results from this study establish the dietary zinc requirement of blue tilapia and indicate that higher levels of supplemental zinc should be included in practical feeds to compensate for reduced zinc bioavailability caused by dietary phytate.     

Efficacy of a vacuum benthos sampler for collecting demersal fish eggs from gravel substratum

Abstract— We used two densities of eggs (low=900 eggs/m²; high=5100 eggs/m²) in laboratory experiments to estimate the recovery efficiency of the Brown benthos sampler for collecting fish eggs from gravel substrate and to determine if differences (e. g., 5-fold) in egg density in the substratum could be detected with the sampler. The mean egg recovery efficiency of the sampler in the low and high density treatments was 30% (SE=8.7) and 35% (SE=3.8), respectively. The difference between the treatment means was not significant. Therefore, data from the two treatments were pooled and used to estimate the recovery efficiency of the sampler (32.7%, SE=4.4). However, we were able to detect a 5× difference in the number of eggs collected with the sampler between the two treatments. Our estimate of the recovery efficiency of the sampler for collecting fish eggs was less than those reported for the sampler's efficiency for collecting benthic macroinvertebrates. The low recovery efficiency of the sampler for collecting fish eggs does not lessen the utility of the device. Rather, ecologists planning to use the sampler must estimate the recovery efficiency of target fauna, especially if density estimates are to be calculated, because recovery efficiency probably is less than 100%.     

<Emphasis Type="Italic">Theileria</Emphasis> (<Emphasis Type="Italic">Babesia</Emphasis>) <Emphasis Type="Italic">equi</Emphasis> and <Emphasis Type="Italic">Babesia caballi</Emphasis> Infections in Horses in Galicia,Spain

The control of equine piroplasmosis is becoming increasingly important to maintain the international market open to the horse industry. The purpose of this study was to demonstrate the occurrence of equine piroplasmosis (Theileria equi and Babesia caballi) in Galicia, north-west Spain, and to compare haematological and serum biochemistry parameters between non-parasitaemic horses and horses parasitaemic with T. equi and B. caballi. Sixty serum samples (control group) were taken from healthy horses pastured on two farms, and examined for evidence of equine T. equi and B. caballi infection by indirect fluorescent antibody test (IFAT). Of the 60 samples, 24 (40%) and 17 (28.3%) samples were positive for T. equi and B. caballi, respectively. Twelve (20%) samples were positive for both parasites. Haematology and serum biochemistry were compared between controls and a series of 36 horses clinically affected by T. equi (25) or B. caballi (11). Compared with the healthy group, there was a 43% and 37% decrease in the haematocrit for T. equi and B. caballi infection, respectively. Parasitaemic horses presented an intense anaemia and serum biochemistry signs of liver damage. The anaemia was more severe in T. equi-infected than in B. caballi-infected horses. Our results suggest that equine piroplasmosis is widespread in the region and is a cause for concern.     

Evaluation of a Multidrug Chemotherapy Protocol (ACOPA II) in Dogs With Lymphoma

A chemotherapeutic protocol using cyclophosphamide, vincristine, prednisone, doxorubicin, and L-asparaginase (ACOPA II) was evaluated in dogs with lymphoma. The response rate for 68 dogs treated with ACOPA II (complete remission [CR] 65%, partial remission [PR] 10%) was lower than that for 41 dogs treated with a related protocol previously evaluated (ACOPA I; CR 76%, PR 12%). Initial treatment with doxorubicin and prednisone did not decrease the prevalence or severity of toxicity during induction. The mortality during induction was 22%. The median duration of CR for dogs treated with ACOPA II was 9 months, with 40% still in remission at 1 year and 21% at 2 years. The rate of CR was lower for dogs with signs of illness at presentation (substage b ) and for dogs weighing less than 15 kg. Age was negatively correlated with survival time and duration of remission. Dogs with immunoblastic lymphoma had a more favorable prognosis than did those with lymphoblastic lymphoma. Survival times were also longer for dogs in substage a at presentation. Seven dogs in which treatment was discontinued while in remission had comparable remission duration to that achieved by dogs receiving long-term maintenance chemotherapy.     

Cardiorespiratory Effects of the Intravenous Administration of Tiletamine-zolazepam to Cats

The hemodynamic and respiratory effects of three doses (9.7, 15.8, and 23.7 mg/kg intravenous [IV]) of a 1:1 combination of tiletamine and zolazepam were studied after isoflurane anesthesia in cats instrumented for the recording of hemodynamic data. Systolic, mean, and diastolic arterial blood pressures were decreased 1 minute after drug administration but then increased above baseline with all three doses. Cardiac output was decreased briefly at 1 minute with the 15.8 and 23.7 mg/kg doses. The rate of development of left ventricular pressure and peripheral vascular resistance decreased at 1 minute but returned to baseline or above by 10 minutes. There were no significant changes in heart rate, central venous pressure, or left ventricular end diastolic pressure. The arterial pH and blood gas measurements reflected the development of respiratory acidosis after administration of 23.7 mg/kg. These results support the conclusions that tiletamine-zolazepam administered intravenously is a useful and comparatively safe anesthetic agent in the cat.