The relationships between scrotal surface temperature,age and sperm quality in stallions

In horses, spermatogenesis normally occurs at an average intratesticular temperature of 35 °C; therefore, mechanisms for testicular thermoregulation are essential. Measuring the scrotal surface temperature by thermography is one of the methodologies used to evaluate the effectiveness of testicular thermoregulation. The objective of this study was to determine the relationship between the control of scrotal surface temperature and sperm quality in horses of different ages. In total, 24 Quarter Horse stallions were divided into three groups: YS (young stallions), AS (adult stallions) and OS (old stallions). Initially, we calculated the testicular volume (TV) and evaluated various aspects of the semen (sperm kinetics, plasma membrane integrity and sperm morphology) for all the animals. We also evaluated rectal temperature (RT), body surface temperature (BST,) and average scrotal surface temperature in the testicular region (SST) before (M0) and after sun exposure (M1). Differences were observed (p<0.05) between the RT and BST before and after sun exposure in all three groups. However, there were no differences (p>0.05) in the SST values at these two time points, thus demonstrating the efficiency of the mechanisms for testicular thermoregulation. The SST was similar (p>0.05) among all three groups. Based on these results, we conclude that fertile stallions of different age groups are able to maintain SST and measuring the heat radiating from the scrotum using a digital infrared thermographer. We can also conclude that measuring the heat radiating from the scrotum using a digital infrared thermographer is a practical and efficient tool for monitoring SST in horses.     

Land‐use changes influence the sporulation and survival of Phytophthora agathidicida,a lethal pathogen of New Zealand kauri (Agathis australis)

Phytophthora agathidicida is the accepted causal agent of dieback in remnant stands of long‐lived indigenous New Zealand kauri (Agathis australis) and poses a significant threat to the long‐term survival of this species. Little is known about the effect of key soil physicochemical characteristics on the growth of P. agathidicida. In this study, we investigated the growth of P. agathidicida in soils collected from adjacent areas under original kauri forest, short rotation pine (Pinus radiata) plantation forest and grazed pastures. A growth response assay was used to quantify asexual (sporangia) and sexual (oospore) spore counts over 8 days in soils sampled from each land‐use. Significantly higher numbers of sporangia (p < 0.001) and oospores (p < 0.01) were found in pasture and pine forest soil within 2 days of the growth assay trials, suggesting these soils may favour asexual/sexual reproduction in the early stages of P. agathidicida establishment compared to kauri forest soils. Additionally, oospore production significantly increased over 8 days in pine forest soil, suggesting that with an increase in inoculum loads, these soils potentially act as pathogen reservoirs. The soil physicochemical properties (e.g., pH, C and N, phosphorus content and electrical conductivity) investigated in this study did not significantly correspond to spore count data between land‐uses, suggesting that differences in growth response are driven by other edaphic factors not explored in the present study.     

Ecotourism, conservation biology, and volunteer tourism: A mutually beneficial triumvirate

Funding for basic conservation research is chronically lacking. The potential for ecotourism to fund conservation research exists, but has been little explored. One branch of ecotourism with funding potential is volunteer tourism, where conservation scientists and recruiting agencies develop research projects and volunteers provide funding and labor. We examine the costs and benefits of a three-way partnership among a conservation research project (The Tambopata Macaw Project), an ecotourism operator (Rainforest Expeditions), and a volunteer-recruiting NGO (the Earthwatch Institute). From November 1999 to December 2006, Macaw Project researchers invested about 1700 h in giving research presentations and interacting with ecotourists and received from Rainforest Expeditions ∼$278,000 worth of salaries, transportation, food, and lodging (total cost to Rainforest Expeditions ∼$98,000). Since 2001, researchers invested 2300 h in training and supervising volunteers and related activities and received from Earthwatch 328 volunteers, ∼13 000 h of volunteer labor and $115,000 in research funding. Rainforest Expeditions received $175,000 in fees from Earthwatch for food and lodging for volunteers. In this association, all parties benefited financially: the research received >$400,000 in cash, goods and services, Earthwatch retained $387,000 in volunteer fees, and Rainforest Expeditions received nearly $300,000 in gross income. Additional benefits to Rainforest Expeditions included services for their guests and free marketing through research related publications and word of mouth. We discuss ways to structure projects to maximize the benefits and the potential of this model for funding other long-term conservation research projects.     

Disseminated Leishmania infantum infection in two sibling foxhounds due to possible vertical transmission

Two sibling foxhounds born to a Leishmania seropositive bitch were presented after testing seropositive for Leishmania. Leishmania infantum infection was detected via histopathology, culture, and quantitative polymerase chain reaction (q-PCR). This is the first report of natural infection with Leishmania infantum with the possibility for vertical transmission in North America.