Tick paralysis in dogs and cats in Australia: treatment and prevention deliverables from 100 years of research

This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all – a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.     

Reproduction potential of Nigerian Meloidogyne spp. and the response of six commercial watermelon cultivars to predominant species

Journal of Plant Diseases and Protection - The reproduction potential of nine single-species Meloidogyne populations and 16 mixed-species communities, recovered from watermelon rhizospheres in...     

Percentage of Ubiquitinated Spermatozoa does not Correlate with Fertilizing Capacity of Thawed Bovine Semen

In the spermatozoa of some species, the ubiquitin–proteasome system detects altered proteins and tags them for elimination by the proteasome. In some species' ejaculates, a high proportion of ubiquitinated spermatozoa (i.e. those having ubiquitin bound to the altered or damaged membrane proteins) has been related to infertility. The aim of this study was to assess whether the percentage of ubiquitinated spermatozoa relates to fertility of dairy bulls and whether ubiquitination increases during protein remodelling that occurs during in vitro spermatic capacitation. Thirty‐two frozen semen straws from four high‐fertility (ReproMax^®) and four normal‐fertility (Normal) Holstein‐Friesian sires were evaluated. Ubiquitinated and capacitated spermatozoa were quantified by sperm ubiquitin tag immunoassay and chlortetracycline stain, respectively. Fertilizing capacity of sires was assessed by in vitro fertilization. No differences were found between Normal and ReproMax^® sires with regard to the observed percentage of ubiquitinated spermatozoa (42.97 ± 3.69% and 49.68 ± 9.27%, respectively; p > 0.05). Additionally, no differences were found in the percentage of ubiquitinated spermatozoa as a consequence of spermatic capacitation in either Normal (42.97 ± 3.69% before capacitation vs 44.67 ± 7.5% after; p > 0.05) or ReproMax^® sires (49.68 ± 9.27% before vs 45.05 ± 7.51% after; p > 0.05). The percentage of ubiquitinated spermatozoa in a thawed sperm samples did not correlate with its in vitro fertilizing capacity; thus, this assay does not prove useful to detect in vivo fertility differences between sires. Additionally, protein degradation occurring during remodelling of the spermatozoon plasma membrane during the capacitation process does not seem to involve the ubiquitin–proteasome system.     

The efficacy of an imidacloprid/moxidectin combination against naturally acquired Sarcoptes scabiei infestations on dogs

The study was undertaken to evaluate and compare the efficacy of an imidacloprid (10% w/v)/moxidectin (2.5% w/v) combination (Advocate Bayer HealthCare, Animal Health) with that of selamectin for the treatment of Sarcoptes scabiei on dogs. Thirty naturally infested dogs, of which one was later withdrawn because of distemper, were allocated to two equal groups and individually housed. The dogs in each group were treated twice, four weeks apart, with either the combination product (0.1 mL/kg body weight) or with selamectin (0.05 mL/kg body weight) administered topically. Skin scrapings were made every 14 days over a period of 50 to 64 days after the first treatment to quantify mite numbers. Clinical signs and the extent of sarcoptic lesions were assessed on each dog when skin scrapings were made. Efficacy was based on the presence or absence of mites, supported by clinical signs associated with canine sarcoptic mange. From Day 22 and onwards no Sarcoptes mites were found in the skin scrapings of any of the treated dogs. Treatment with the imidacloprid/moxidectin formulation or with selamectin was highly effective against Sarcoptes scabiei and resulted in an almost complete resolution of clinical signs within 50 to 64 days after the initial treatment.     

Galenia africana L. poisoning in sheep and goats: hepatic and cardiac changes.

Lesions in 4 field cases (3 sheep and 1 goat) of 'waterpens' or water belly, caused by the plant Galenia africana, are described. The clinical pathological and pathological findings in 7 sheep which were drenched with toxic plant material are also reported. Inappetence, ruminal stasis and apathy as well as tachycardia were noticed in some of the sheep towards the end of the dosing period. The most prominent clinical pathological change in the experimental animals was an increase in the activity of gamma-glutamyltransferase which in some animals occurred within days after commencement of dosing. This indicates liver involvement in the early stages of the intoxication, and at this stage no heart abnormalities were detected clinically, clinical pathologically or with cardiac function tests. Decrease in cardiac function were recorded in 2 sheep towards the end of the dosing period. Liver and heart lesions were present in all the animals. In some cases hepatic changes were mild and characterized by dilation of central veins and sinusoids and, less commonly, centrilobular fibrosis. More advanced lesions included centrilobular fibrosis and bridging between neighbouring lobules with adjacent areas of coagulative necrosis, lysis and ballooning degeneration of hepatocytes. Myocardial changes occurred in the free ventricular walls and interventricular septum and comprised hypertrophy of myocytes with consequent degeneration and necrosis and fibrosis. In cases of longer duration myocytes were diffusely atrophic with scattered groups of remaining hypertrophic fibres. The clinical pathological and pathological features suggest that G. africana is primarily hepatotoxic with myocardial involvement occurring only in the terminal stages of the intoxication.     

Johne's disease in alpacas (Lama pacos) in Australia

SUMMARY: Johne's disease was diagnosed in 10 alpacas ( Lama pacos ) in Australia between February 1993 and May 1994. Eight of the animals were between 12 and 24 months of age, one was a 6-year-old female, and one was a 4-year-old male. Five, including the 6-year-old and the 4-year-old alpacas, showed weight loss and diarrhoea before death or slaughter. The other cases showed no clinical signs of Johne's disease but 4 gave a positive result on faecal culture and one gave a positive result on testing with the caprine ACID assay and had acid-fast organisms in its faeces. At necropsy, all cases had grossly enlarged mesenteric lymph nodes. Johne's disease was diagnosed after histological examination of the lymph nodes with conventional culture and polymerase chain reaction testing of tissue samples. This report outlines the clinical, epidemiological, and pathological findings in these cases.     

Aboveground biomass production of a semi-arid southern African savanna: towards a new model

Following a field campaign to determine the species composition, canopy cover, aboveground annual production and leaf area index (LAI) of the semi-arid savanna of north-western Namibia, we present a production model that can be used by graziers to determine the livestock carrying capacity. The model predicts the annual aboveground net primary production (ANPP) from regression equations of canopy cover by annual production fraction for plant functional classes. We tested the output of the model against another fully independent net primary production (NPP) model, namely the MODIS NPP product. The mean MODIS NPP for the 29 sites was 343 ± 22?kg dry matter (DM) ha^?1 y^?1 as opposed to 285 ± 142?kg DM ha^?1 y^?1 for the fAP model that used the regression method (p < 0.01). As a proof of concept, these landscape-scale ANPP values are used to calculate a recommended livestock carrying capacity for the Ehirovipuka Communal Conservancy, a 1 980 km² communal area with both wildlife and livestock populations. In addition, we also provide details of a field method for predicting landscape-scale LAI from line transect data. This approach can be used to ground reference the LAI values generated from the MODIS LAI product.     

Obtaining Wisent early blastocyst in vitro is a basic for protection and creation of biodiversity for this threatened species

Wisent, or European bison (Bison bonasus), is listed as “vulnerable” on the IUCN Red List of Threatened Species and is therefore protected by international law. For the first time, a Wisent embryo has been obtained in vitro. This procedure creates a new opportunity to protect and increase Wisent reproductive potential and thereby opens new possibilities for the establishment of a controlled and broad reserve of the gene pool.