Assessment of the combination of spinosad and milbemycin oxime in preventing the development of canine Angiostrongylus vasorum infections

Angiostrongylus vasorum is an increasingly reported parasite in Europe that develops in dogs after ingestion of infective third stage larvae (L3) that reside in gastropod molluscs which are needed to complete the parasite's life-cycle. Infection can produce a diversity of clinical signs, determined by involvement of the respiratory, neurological, and/or coagulation system, with a likely fatal outcome in the absence of treatment. Few drugs have been shown to reliably prevent infection, and data on treatment of infections is limited. A controlled, randomized, partially blinded laboratory study was therefore executed to evaluate the efficacy and safety of a combination tablet of spinosad/milbemycin oxime in dogs inoculated with approximately 250 A. vasorum L3. Sixteen healthy nematode free adult dogs were randomly allocated to two study groups of 8 dogs each. Thirty days post inoculation (dpi) all dogs in the fed state were treated: dogs in group B were treated with spinosad and milbemycin oxime at the dose rates of 45–60 mg/kg and 0.75–1.0 mg/kg bodyweight, respectively, approximately the lower half portion of the expected full unit dose range; dogs in group A were treated with placebo tablets. All dogs were euthanized and necropsied 56–58 dpi. The heart and lungs were examined to determine the presence of A. vasorum. All placebo group dogs were infected at necropsy with counts ranging from 22 to 98 adult worms and a geometric mean worm count of 55.2. In contrast, the geometric mean worm count in the spinosad/milbemycin oxime group was 0.7 with worm numbers ranging from 0 to 8. The results of this study demonstrate that a single treatment with the tablet combination of spinosad and milbemycin oxime administered 30 dpi provided 98.8% preventive efficacy against development of adult A. vasorum infections. Monthly treatments with spinosad and milbemycin oxime have the potential to prevent the establishment of infections with A. vasorum in dogs.     

A Chemoautotrophically Based Cave Ecosystem

Microbial mats discovered in a ground-water ecosystem in southern Romania contain chemoautotrophic bacteria that fix inorganic carbon, using hydrogen sulfide as an energy source. Analysis of stable carbon and nitrogen isotopes showed that this chemoautotrophic production is the food base for 48 species of cave-adapted terrestrial and aquatic invertebrates, 33 of which are endemic to this ecosystem. This is the only cave ecosystem known to be supported by in situ autotrophic production, and it contains the only terrestrial community known to be chemoautotrophically based.     

Growth of SiO2 at room temperature with the use of catalyzed sequential half-reactions

Films of silicon dioxide (SiO2) were deposited at room temperature by means of catalyzed binary reaction sequence chemistry. The binary reaction SiCl4 + 2H2O --> SiO2 + 4HCl was separated into SiCl4 and H2O half-reactions, and the half-reactions were then performed in an ABAB ellipsis sequence and catalyzed with pyridine. The pyridine catalyst lowered the deposition temperature from >600 to 300 kelvin and reduced the reactant flux required for complete reactions from approximately 10(9) to approximately 10(4) Langmuirs. Growth rates of approximately 2.1 angstroms per AB reaction cycle were obtained at room temperature for reactant pressures of 15 millitorr and 60-second exposure times with 200 millitorr of pyridine. This catalytic technique may be general and should facilitate the chemical vapor deposition of other oxide and nitride materials.     

Induced Acute Ruminai Acidosis in Goats Treated with Yeast (Saccharomyces cerevisiae) and Bicarbonate

Ruminai acidosis was induced in twenty-one 10-month-old West African Dwarf Goats by feeding a suspension of 80 g wheat flour per kg body-weight (day 0) through a stomach tube. Ruminai and systemic acidosis was diagnosed on day 1 in all goats. Clinical signs included loss of rumination and appetite, trembling, and watery diarrhoea. The detection of acidic faeces during the first 24h was considered of diagnostic importance. Subgroups were treated orally on days 1,2, and 3 either with 1 g of sodium bicarbonate per kg bodyweight, with 1 g of baking yeast per kg, or with a combination of these treatments at 0.5 g of each per kg. A fourth group served as untreated controls.Peroral bicarbonate neutralization was highly effective in the treatment of rumen acidosis, whereas the use of yeast was found ineffective. The combined treatment had a moderate effect probably due to the bicarbonate.Three fatal cases (60%) occurred in the untreated group compared with none in the bicarbonate group, and 2 in each of the remaining groups. This corresponded to 33% of the yeast treated group and 40% of the combined treated group. Details were given on post mortem examinations performed on all survivors on day 11. Lesions included subacute rumenitis and abomasal ulcers. No lesions were found in 3 of the bicarbonate treated goats and in 2 of the animals receiving combined treatment.     

Sawfly poisoning in sheep and goats

In September 1984 some sheep in a flock of 250 suffered depression, anorexia, incoordination and difficulty in rising; 50 ewes and weaners died. Post mortem examination revealed petechial bleeding, massive acute liver necrosis and in some animals degeneration of the kidney tubules. The rumen and gut contained many larvae of the blue-black birch sawfly (Arge pullata). Laboratory and field observations indicated that these were the cause of the illness.     

Accuracy of an anaemia scoring chart applied on goats in sub-humid Kenya and its potential for control of Haemonchus contortus infections

We tested the practical application of an anaemia scoring chart (the FAMACHA chart) as a method for controlling Haemonchus contortus in goats kept under smallholder conditions in a sub-humid area of Central Kenya. The objectives were: (1) to test the accuracy of the FAMACHA chart in identifying anaemic goats (PCV< or =18); (2) to quantify the proportion of goats left untreated at farm level when using the chart. On each of two farms, Small East African goats of various ages were allocated to two treatment groups; a FAMACHA group (F1 (n=34) and F2 (n=31) on farms 1 and 2, respectively) and a control group (C1 (n=34) and C2 (n=30)). In F1 and F2 goats with a FAMACHA score of 3, 4 or 5 were treated with anthelmintic after scoring. In C1 and C2 goats were treated every 4 weeks from 15 February to 20 July. Every 2 weeks all goats were scored with the FAMACHA chart and weighed. Furthermore, faecal samples were collected for faecal egg counts (FEC) and blood samples were collected for packed cell volume (PCV) determination. H. contortus was found to be the predominant nematode on both farms. The mean FECs were higher on farm 1 compared to farm 2, while in contrast the mean PCV levels were lowest on farm 2. The latter was most likely due to the presence of Fasciola spp., flea and tick infections on farm 2. The accuracy of the chart was evaluated by using PCV as the gold standard for anaemia (PCV< or =18%). The mean percentage of false-negative scorings per sampling was 0.7% on farm 1 and 1.6% on farm 2, while the mean percentage of false-positive scorings was 9.7% and 21.4%, respectively. It is most likely that the accuracy of the chart was negatively affected by the concurrent parasite infections on farm 2. The mean proportion of untreated goats per sampling was 89% and 77% on farm 1 and farm 2. It was concluded that the FAMACHA chart can be a valuable tool for decision-making in control of H. contortus in goats kept under smallholder conditions, without morbidity or mortality unacceptable to the farmer. The application may further reduce the risk of development of anthelmintic resistance by increasing refugia. However, caution should be taken under conditions where other anaemia-causing parasites are present (e.g. Fasciola spp. and ecto-parasites), since this possibly decreases the accuracy of the FAMACHA chart.     

Squamous cell carcinoma in a tuatara (Sphenodon punctatus)

CASE HISTORY: A mature male tuatara was presented with a history of recurrent cloacal prolapse.

CLINICAL AND PATHOLOGICAL FINDINGS: The prolapsed tissue included a 12 mm diameter mass, which histologically showed cords and nodules of neoplastic epithelial cells.

DIAGNOSIS: The mass was diagnosed as a squamous cell carcinoma with ulceration of the overlying stratified squamous epithelium and diffuse inflammation of the surrounding dermis.

CLINICAL RELEVANCE: This case presented a rare opportunity to investigate squamous cell carcinoma in a long-lived lower vertebrate species. Future recurrence or metastasis of the mass may add useful information to the current base of knowledge of the behaviour of malignant neoplasms in reptiles.