Pinyon and Juniper Encroachment into Sagebrush Ecosystems Impacts Distribution and Survival of Greater Sage-Grouse

In sagebrush (Artemisia spp.) ecosystems, encroachment of pinyon (Pinus spp.) and juniper (Juniperus spp.; hereafter, “pinyon-juniper”) trees has increased dramatically since European settlement. Understanding the impacts of this encroachment on behavioral decisions, distributions, and population dynamics of greater sage-grouse (Centrocercus urophasianus) and other sagebrush obligate species could help benefit sagebrush ecosystem management actions. We employed a novel two-stage Bayesian model that linked avoidance across different levels of pinyon-juniper cover to sage-grouse survival. Our analysis relied on extensive telemetry data collected across 6 yr and seven subpopulations within the Bi-State Distinct Population Segment (DPS), on the border of Nevada and California. The first model stage indicated avoidance behavior for all canopy cover classes on average, but individual grouse exhibited a high degree of heterogeneity in avoidance behavior of the lowest cover class (e.g., scattered isolated trees). The second stage modeled survival as a function of estimated avoidance parameters and indicated increased survival rates for individuals that exhibited avoidance of the lowest cover class. A post hoc frailty analysis revealed the greatest increase in hazard (i.e., mortality risk) occurred in areas with scattered isolated trees consisting of relatively high primary plant productivity. Collectively, these results provide clear evidence that local sage-grouse distributions and demographic rates are influenced by pinyon-juniper, especially in habitats with higher primary productivity but relatively low and seemingly benign tree cover. Such areas may function as ecological traps that convey attractive resources but adversely affect population vital rates. To increase sage-grouse survival, our model predictions support reducing actual pinyon-juniper cover as low as 1.5%, which is lower than the published target of 4.0%. These results may represent effects of pinyon-juniper cover in areas with similar ecological conditions to those of the Bi-State DPS, where populations occur at relatively high elevations and pinyon-juniper is abundant and widespread.     

Rabies surveillance in the United States during 2011

Summary-During 2011, 49 states and Puerto Rico reported 6,031 rabid animals and 6 human rabies cases to the CDC, representing a 1.9% decrease from the 6,153 rabid animals and 2 human cases reported in 2010. Approximately 92% of reported rabid animals were wildlife. Relative contributions by the major animal groups were as follows: 1,981 raccoons (32.8%), 1,627 skunks (27.0%), 1,380 bats (22.9%), 427 foxes (7.1%), 303 cats (5.0%), 65 cattle (1.1%), and 70 dogs (1.2%). Compared with 2010, there was a substantial increase in the number of rabid skunks reported. Six cases of rabies involving humans were reported from California, Massachusetts, New Jersey, New York, and South Carolina. Three cases reported from Massachusetts, New Jersey, and New York were determined to be a result of canine rabies virus variants acquired outside the United States.     

Locally Grown Oysters in Hawai‘i: Chef Preference and Local Premium?

Locally grown oysters became available in Hawai‘i in 2014, for the first time in decades. It is unclear if these bivalve shellfish will successfully infiltrate the market when imported products similar in nature have long been the only source of fresh, shell stock products. This study investigates chef preferences for oyster attributes to determine marginal willingness to pay for locally grown oysters. A survey containing a questionnaire and a choice experiment was administered to restaurant chefs throughout Hawai‘i who currently offer oysters on their menus. The study examines trade‐offs made between attributes related to price, growout site, freshness, and supply constancy, respectively. Responses were aggregated and data were fit to a random parameters logit model. Results suggest that respondents derive the most utility from oysters that are fresh, grown locally, and supplied on an as‐available basis. The least desired products are, therefore, those that are frozen, imported from foreign sources, and supplied on a set schedule. Chefs are willing to pay an additional $5.25 for one dozen oysters that are grown locally. This evidence of an existing price premium indicates that labeling local oysters as such may be a valuable marketing strategy.     

The effectiveness of the drugs Dovenix and Bilevon(R)-Injection against liver fascioliasis (Fasciola hepatica, Linné 1758) in cattle]

Dovenix and Bilevon-injection (manufactured by SPECIA, France and BAYER, West Germany, respectively) were tested for their anthelmintic efficacy against Fasciola hepatica in cattle. The drugs proved highly effective against both adult and immature flukes. The faeces of the treated animals were negative for F. hepatica eggs when examined 91 days after the treatment. In experiments with rats Dovenix and Bilevon-injection were tolerated up to eight times and ten times higher doses than the normal therapeutic dose, respectively.     

On the pathogenesis of anaemia and leukopenia in filarial (Litomosoides carinii) infection of Mastomys natalensis.

Mastomys natalensis infected with the filarial parasite Litomosoides carinii show anaemia and leukopenia. Alterations start with the onset of microfilaraemia. Anaemia is temporally macrocytic (up to 80 days after infection), subsequently normocytic and hypochromic, accompanied by reticulocytosis. Increased intravascular haemolysis (i) and functional disorders of the haemopoetic system (ii) are involved in the pathogenesis. i: Circulating erythrocytes showed increased osmofragility. Hypoglycaemia demonstrated in parasitaemic animals may be one reason. ii: Histological and electron microscopical investigations of the bone marrow revealed markedly enhanced haemopoiesis in infected animals. However, a high proportion of cells was found pathologically altered already beginning in the late prepatency and increasing in the further course of infection. Thus, dyshaemopoiesis may result in the production of morphologically and functionally aberrant cells which are rapidly eliminated by the MPS which is highly activated in L. carinii infected M. natalensis.     

Strain typing of German transmissible spongiform encephalopathies field cases in small ruminants by biochemical methods

Following the implementation of a large scale transmissible spongiform encephalopathies (TSE) surveillance programme of small ruminants, evidence for a natural transmission of bovine spongiform encephalopathy (BSE) to a French goat has been found. During the years 2002-2004, a massive TSE rapid testing programme on >250,000 small ruminants was carried out in Germany. In this national survey, 186 scrapie-affected sheep were found which originated from 78 flocks. The majority of these cases were of the classical TSE type (115 sheep belonging to 14 outbreaks). However, 71 cases coming from 64 flocks were of the novel atypical scrapie type. According to the regulation EU 999/2001, all TSE cases in small ruminants have to be examined by strain typing methods to explore any possibility of the existence of BSE cases in the field sheep population. Here we report on a biochemical typing strategy (termed FLI-test), which includes the determination of molecular masses, antibody binding affinities and glycosylation pattern of the TSE induced abnormal prion protein. Based on this typing approach none of the analysed German classical TSE outbreaks (total number of analysed sheep: 36) displayed biochemical features indicative for a BSE infection. However, in two cases distinct but BSE-unrelated PrP(Sc) types were found, which alludes to the existence of different scrapie strains in the German sheep population.     

Quantification of Wheat spindle streak mosaic virus and Soil borne cereal mosaic virus in resistance testing of field samples of triticale using real-time RT-PCR

Journal of Plant Diseases and Protection - Triticale, a cross between rye and wheat, is a crop important for animal feed and the production of biogas and ethanol. Soil-borne viruses found in wheat...