Association between the presence of serum antibodies against Neospora spp. and fetal loss in equines

A study of the association between the presence of serum antibodies against Neospora spp. and fetal loss was performed using serum samples of horses submitted to the laboratory for the detection of antibodies to Equine Herpesvirus-1 and Equine Infectious Anemia Virus. The sera submitted for equine infectious anemia testing were from horses declared healthy and those submitted for the detection of antibodies to Equine Herpesvirus-1 were from mares with late clinical signs of reproductive disorders or males living in close contact with diseased mares. For the detection of Neospora spp. infection, the immunofluorescent antibody test was employed, using a cut-off titer of 50 as significant for the presence of antibodies. Among the 483 mares in the diseased group, 15.1% (73/483) was reactant, while 5.8% (19/325) was seropositive in the healthy group. The results show that late clinical signs of reproductive disorders in mares are positively associated (p<0.001) to infection with protozoa belonging to the genus Neospora and point to the fact that the participation of this group of coccidia in the genesis of reproductive disorders in equine must be investigated.     

Prevalence of Neospora caninum infection in Australian (NSW) dairy cattle estimated by a newly validated ELISA for milk

AIM: To determine the performance characteristics of an Institut Pourquier (IP) enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against Neospora caninum in bovine milk and subsequent determination of the prevalence of N. caninum infection in New South Wales (NSW) dairy cattle. METHODS: Matching serum and milk samples from 93 cattle were assayed in two commercially available ELISAs for the detection of anti-N. caninum antibodies. Serum test results of one ELISA (IDEXX) were used to determine the N. caninum infection status of the cattle. Optimised cut-off values for the IP ELISA using milk samples were determined by two-graph receiver operating characteristic (TG-ROC) analysis and then applied to a representative sample of 398 milk samples from dairy herds around NSW. RESULTS: When this ELISA was applied to a representative collection of 398 milk samples from dairy cattle across NSW it demonstrated a 21.1% prevalence of N. caninum infection in those cattle. From the TG-ROC analysis an IP ELISA protocol was derived which suggested a cut-off threshold that would allow milk testing with 97% sensitivity and specificity, respectively, relative to serum testing. CONCLUSIONS: The prevalence of N. caninum in NSW dairy cattle was higher than previously believed. When used on individual milk samples this ELISA demonstrated high sensitivity and specificity and so could be used to accurately identify N. caninum infection. TG-ROC analysis of the IP ELISA optimised the protocol and prescribed cut-off values enabling the ELISA to be used for the screening of N. caninum antibodies in the milk of dairy cattle.     

Pruritus possibly associated with a portosystemic shunt in a bichon frise puppy

A bichon frise puppy was presented with generalized pruritus. At 22 weeks, a portosystemic shunt was diagnosed. Correction of the shunt led to resolution of the pruritus. Pruritus associated with hepatobiliary disease is well documented in humans; this case suggests that hepatobiliary disease may be associated with pruritus in dogs.     

MCPA (4-Chloro-2-ethylphenoxyacetate) resistance in hemp-nettle (Galeopsis tetrahit L.)

The physiological basis for MCPA resistance in a hemp-nettle (Galeopsis tetrahit L.) biotype, obtained from a MCPA-resistant field population, was investigated. Dose-response studies revealed that the resistance factor for MCPA, based on GR50 comparisons of total dry weight of resistant (R) and susceptible (S) plants, was 3.3. Resistance factors for fluroxypyr, dicamba, 2,4-D, glyphosate, and chlorsulfuron were 8.2, 1.7, 1.6, 0.7, and 0.6, respectively. MCPA resistance was not due to differences in absorption, because both R and S biotypes absorbed 54% of applied [14C]MCPA 72 h after treatment. However, R plants exported less (45 vs 58% S) recovered 14C out of treated leaves to the apical meristem (6 vs 13% S) and root (32 vs 38% S). In both biotypes, approximately 20% of the 14C recovered in planta was detected as MCPA metabolites. However, less of the 14C recovered in the roots of R plants was MCPA. Therefore, two different mechanisms protect R hemp-nettle from MCPA phytotoxicity: a lower rate of MCPA translocation and a higher rate of MCPA metabolism in the roots. In support of these results, genetic studies indicated that the inheritance of MCPA resistance is governed by at least two nuclear genes with additive effects.     

Nonrandom processes maintain diversity in tropical forests

An ecological community's species diversity tends to erode through time as a result of stochastic extinction, competitive exclusion, and unstable host-enemy dynamics. This erosion of diversity can be prevented over the short term if recruits are highly diverse as a result of preferential recruitment of rare species or, alternatively, if rare species survive preferentially, which increases diversity as the ages of the individuals increase. Here, we present census data from seven New and Old World tropical forest dynamics plots that all show the latter pattern. Within local areas, the trees that survived were as a group more diverse than those that were recruited or those that died. The larger (and therefore on average older) survivors were more diverse within local areas than the smaller survivors. When species were rare in a local area, they had a higher survival rate than when they were common, resulting in enrichment for rare species and increasing diversity with age and size class in these complex ecosystems.     

Abnormal prion protein in ectopic lymphoid tissue in a kidney of an asymptomatic white-tailed deer experimentally inoculated with the agent of chronic wasting disease

Chronic wasting disease (CWD), a transmissible spongiform encephalopathy (TSE) of deer and elk, is one of a group of fatal, neurologic diseases that affect several mammalian species, including human beings. Infection by the causative agent induces accumulations of an abnormal form of prion protein (PrPres) in nervous and lymphoid tissues. This report documents the presence of PrPres within ectopic lymphoid follicles in a kidney of a white-tailed deer that had been experimentally inoculated by the intracerebral route with CWD 10 months previously. The deer was nonclinical, but spongiform lesions characteristic of TSE were detected in tissues of the central nervous system (CNS) and PrPres was seen in CNS and in lymphoid tissues by immunohistochemistry. The demonstration of PrPres in lymphoid tissue in the kidney of this deer corroborates a recently published finding of PrPres in lymphoid follicles of organs other than CNS and lymphoid tissues in laboratory animals with TSE (scrapie).     

Uptake of Macro- and Micro-Nutrients into Leaf,Woody, and Root Tissue of Populus after Irrigation with Landfill Leachate

ABSTRACT

Information about macro- and micro-nutrient uptake and distribution into tissues of Populus irrigated with landfill leachate helps to maximize biomass production and understand impacts of leachate chemistry on tree health. We irrigated eight Populus clones (NC 13460, NCI4O18, NC14104, NC14106, DM115, DN5, NM2, NM6) with fertilized (N, P, K) well water(control) or municipal solid waste landfill leachate weekly during 2005 and 2006 in Rhinelander, Wisconsin, USA. During Aug. 2006, we tested for differences in total N, P, K, Ca, Mg, S, Zn, B, Mn, Fe, Cu, Al, and Pb concentration in preplanting and harvest soils; and in leaf, woody (stems?+?branches), and root tissue. Other than N, leachate did not increase the soil concentration of elements relative to preplanting levels. There was broad genotypic variation for tissue concentrations, with clone-specific uptake for most elements. Nitrogen, P, K, Ca, Mg, S, B, and Mn concentrations were greatest in leaves and least in woody tissue, while those of Fe, Cu, and Al were greatest in roots and least in leaves and woody tissue. Overall, successful uptake of nutrients without impacts to tree health validated the use of landfill leachate as an irrigation and fertilization source for Populus.     

Mushroom toxicosis in dogs in general practice causing gastroenteritis,ptyalism and elevated serum lipase activity

Mushroom toxicosis is rarely diagnosed in dogs and is poorly reported in the veterinary literature. This report suggests that mushroom toxicosis is a potentially under‐diagnosed condition in first opinion practice in the UK. Nine dogs with clinical signs consistent with mushroom toxicosis were identified from the records of an out‐of‐hours emergency service between August 2010 and January 2011. Four dogs were later excluded because of clinical inconsistencies. Clinical signs included acute profuse ptyalism (5/5), diarrhoea (5/5), vomiting (4/5), hypovolaemia (4/5), stuporous (3/5) or obtunded mentation (1/5), miosis (2/5) and hypothermia (2/5). Serum lipase activity was elevated in 4/4 dogs; canine‐specific pancreatic lipase was elevated in the remaining dog. Four dogs recovered with aggressive intravenous fluid therapy, analgesia and supportive care; the remaining dog was euthanased due to severe clinical signs and financial constraints. Mushroom toxicosis is an important differential diagnosis for acute gastroenteritis and one possible cause of some cases of “Seasonal Canine Illness”. Affected dogs may demonstrate elevated pancreatic enzymes and mushroom toxicosis should be considered in cases of elevated lipase or abnormal semi‐quantitative canine‐specific pancreatic lipase activities.     

Virulence profiles of enterotoxigenic, shiga toxin and enteroaggregative Escherichia coli in South African pigs

Enterotoxigenic Escherichia coli (ETEC) and shiga toxin E. coli (STEC) are important causes of colibacillosis in piglets. Recently, enteroaggregative E. coli heat-stable enterotoxin 1 (EAST-1) has been implicated in pig diarrhoea. This study investigated the prevalence of enterotoxin [heat-labile toxins (LT), heat-stable toxin a (STa), heat-stable toxin b (STb)], shiga toxins (Stx1, Stx2, Stx2e), enteroaggregative heat-stable E. coli (EAST-1), associated fimbriae (F4, F5, F6, F41, F18ab, F18ac) and non-fimbrial adhesins [adhesin involved in diffuse adherence 1 (AIDA-1), attaching and effacing factor, porcine attaching- and effacing-associated factor] in South African pigs. A total of 263 E. coli strains were isolated from Landrace (n?=?24), Large White (n?=?126), Duroc (n?=?28) and indigenous (n?=?85) breeds of piglets aged between 9 and 136 days. PCR was used in the analysis. Virulent genes were detected in 40.3 % of the isolates, of which 18.6, 0.4 and 17.5 % were classified as ETEC, STEC and enteroaggregative E. coli (EAEC), respectively. Individual genes were found in the following proportions: STb (19.01 %), LT (0.4 %), STa (3.4 %), St2xe (1.1 %) and EAST-1 (20.2 %) toxins. None of the tested fimbriae were detected in ETEC and STEC isolates. About one third of the ETEC and STEC isolates was tested negative for both fimbrial and non-fimbrial adhesins. Twenty-five pathotypes from ETEC-, EAEC- and STEC-positive strains were identified. Pathotypes EAST-1 (30.2 %), STb (13.2 %) and STb/AIDA-1 (10.4 %) were most prevalent. The study provided insight on possible causes of colibacillosis in South African pigs.