Is Competitive Behavior Controlled by its Consequences? The Effects of Omission Training on Competitive Behavior in Rats

Recent research has examined competitive behavior in rats. When multiple rats are placed in an open field with a single feeder delivering pellets on a Variable Interval Schedule, the rats typically engage in a competitive wrestling response near the feeder tube. This response has been observed in several different experiments, but little is known about its specific nature. One possibility is that the response is a traditional operant. Although there is no explicit contingency with reinforcement, rats that do not engage in the response are unlikely to consume pellets. Alternatively, the competitive response might represent a species-specific foraging mode, controlled by the competitive foraging environment but not controlled by its consequences. The present experiments utilize an omission procedure, in which engaging in competitive responses cancels delivery of reinforcement. In Experiment I there was no difference in the rate of competitive response between the omission phase and the baseline phases. Although it would be tempting to conclude from these results that the behavior is not subject to its consequences, additional explanations must first be ruled out. The second experiment was aimed at eliminating any possible variables that may have affected these results to rule out possible alternate explanations. The results have implications for various biologically-oriented models of foraging

USE OF COPPER SULFATE TO CONTROL\u3ci\u3e HAEMONCHUS CONTORTUS \u3c/i\u3eINFESTATION IN HAMPSHIRE EWES

Two studies were conducted to evaluate the effectiveness of using copper sulfate (CuSO4) as a drench in Hampshire ewes to control stomach worms (Haemonchus contortus). A study was conducted to assess the effectiveness of CuSO4 to control gastrointestinal nematodes (GIN) over a three year period. Ewes were FAMACHA scored, hematocrit evaluated for packed cell volume (PCV), and fecal egg counts (FEC) were determined from 2007 through 2009. Ewes received only CuSO4 to control GIN. Ewes with FEC exceeding 6,000 eggs/g feces were drenched. A separate study during the summer of 2008 assessed the potential of CuSO4 drench to cause copper toxicity in Hampshire ewes. Eighty-four ewes were blocked to one of two treatments according to parity and balanced for FEC. One group received CuSO4 (D) and the other was not drenched (ND). Jugular blood samples were collected at pre-determined intervals after CuSO4 was administered to D ewes. Serum was analyzed for aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine kinase (CK). Elevated serum levels indicate copper toxicity. Results suggest CuSO4 has the potential to control stomach worms in Hampshire ewes without causing copper toxicity

Macacine Herpesvirus 1 in Long-Tailed Macaques, Malaysia, 2009–2011

Macacine herpesvirus 1 (MaHV1; B virus) naturally infects macaques (Macaca spp.) and can cause fatal encephalitis in humans. In Peninsular Malaysia, wild macaques are abundant, and translocation is used to mitigate human–macaque conflict. Most adult macaques are infected with MaHV1, although the risk for transmission to persons who handle them during capture and translocation is unknown. We investigated MaHV1 shedding among 392 long-tailed macaques (M. fascicularis) after capture and translocation by the Department of Wildlife and National Parks in Peninsular Malaysia, during 2009–2011. For detection of MaHV1 DNA, PCR was performed on urogenital and oropharyngeal swab samples. Overall, 39% of macaques were shedding MaHV1 DNA; rates of DNA detection did not differ between sample types. This study demonstrates that MaHV1 was shed by a substantial proportion of macaques after capture and transport and suggests that persons handling macaques under these circumstances might be at risk for exposure to MaHV1

Minimal acute rejection in pediatric lung transplantation - does it matter?

In adult lung transplantation, a single minimal AR episode is a significant predictor of BOS independent of other factors. However, the significance of single minimal AR episodes in children is unknown. A retrospective, multi-center analysis was performed to determine whether isolated single AR episodes are associated with an increased BOS risk in children. Risk factors for BOS, death, or re-transplantation, and a combined outcome of BOS, death, or re-transplantation were assessed. Original data included 577 patients (<21 yr of age). A total of 383 subjects were eligible for the study. Fifteen percent of patients developed BOS, and 13% of patients either died or underwent re-transplant within one-yr post-transplant. In the multivariable survival model for time to BOS, there was no significant risk to developing BOS after a single minimal AR (A1) episode (HR 1.7, 95% CI 0.64-4.8; p=0.28). Even after a second minimal AR episode, no significant risk for BOS was appreciated. However, a single episode of mild AR (A2) was associated with twice the risk of BOS within one-yr post-transplant. In this select cohort, a single minimal AR episode was not associated with an increased risk for BOS within one yr following lung transplantation, in contrast to previous reports in adults

Environmental DNA Methods for Ecological Monitoring and Biodiversity Assessment in Estuaries

Environmental DNA (eDNA) detection methods can complement traditional biomonitoring to yield new ecological insights in aquatic systems. However, the conceptual and methodological frameworks for aquatic eDNA detection and interpretation were developed primarily in freshwater environments and have not been well established for estuaries and marine environments that are by nature dynamic, turbid, and hydrologically complex. Environmental context and species life history are critical for successful application of eDNA methods, and the challenges associated with eDNA detection in estuaries were the subject of a symposium held at the University of California Davis on January 29, 2020 (https:// marinescie nce.ucdavis. edu/engagement/past-events/edna). Here, we elaborate upon topics addressed in the symposium to evaluate eDNA methods in the context of monitoring and biodiversity studies in estuaries. We first provide a concise overview of eDNA science and methods, and then examine the San Francisco Estuary (SFE) as a case study to illustrate how eDNA detection can complement traditional monitoring programs and provide regional guidance on future potential eDNA applications. Additionally, we offer recommendations for enhancing communication between eDNA scientists and natural resource managers, which is essential for integrating eDNA methods into existing monitoring programs. Our intent is to create a resource that is accessible to those outside the field of eDNA, especially managers, without oversimplifying the challenges or advantages of these methods.ISSN:1559-2731ISSN:1559-272