Plasma clearance and tissue uptake of native and desialylated equine gonadotropins

Equine luteinizing hormone (eLH), equine follicle stimulating hormone (eFSH) and equne chorionic gonadotropin (eCG) were desialylated and their plasma disappearance, tissue uptake and degradation determined. Both native hormones and their desialylated derivatives were radioiodinated and injected intravenously into male rats. Plasma samples were taken at different time intervals and examined for both total and trichloroacetic acid (TCA) precipitable radioactivity. Disappearance curves for each hormone consisted of two exponential components: a fast clearance followed by a slow phase. The apparent $\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ of the fast component for native eCG, eLH and eFSH were 18.3 min, 17.0 min and 17.1 min, respectively; this is in contrast to their desialylated derivatives which had a $\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ of 2.8 min, 4.9 min and 7.1 min, respectively. The slower component for native and desialylated eCG had at $\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ of 355.5 min and 171.2 respectively. After TCA precipitation more than 90 percent of the radioactivity in plasma was in the pellet, whereas in urine almost 95 percent of the radioactivity was in the TCA supernatant. Coincident with the disappearance of the hormone from the plasma its uptake and release was observed in liver, kidney, testis, and muscle tissue. Gel filtration data on plasma and urine samples indicated that the former had mostly intact hormone in contrast with the latter. Together these results indicate that eLH, eFSH and eCG disappear from the plasma of male rats in a biphasic manner with a rate slower than their desialylated derivatives.     

Environmental conflicts and nature reserves: redesigning Sierra San Pedro Mártir National Park, Mexico

Nature reserves can be considered a land-use category that competes with other land-uses for territory. Therefore, one fundamental goal in conservation planning is to arrive at nature reserve designs that protect the most valuable lands for conservation, and avoid the inclusion of tracts of land valuable for other stakeholders. However, the complexity of conservation issues, the urgency for protecting critical biodiversity components and the lack of data have forced planners to rely on expert knowledge and public participation for designing nature reserves. Handling expert and public knowledge is challenging because it can be subjective, biased, value laden, context specific, and ambiguous. Here, we present a land suitability assessment (LSA) approach for designing the Sierra San Pedro Mártir National Park, Baja California, Mexico. The LSA allowed us the optimal configuration SSPM in terms of delimitation (inclusion of the most valuable biological resources) and zoning (segregation of incompatible land-uses).     

Evaluation and Comparison of 2 On‐Farm Tests for Estimating Somatic Cell Count in Quarter Milk Samples from Lactating Dairy Cattle

Background

The somatic cell count (SCC) is commonly used to monitor udder health and diagnose subclinical intramammary infection (IMI) in dairy cattle.

Hypothesis

The Somaticell test (ST) 2 and California mastitis test (CMT) are clinically useful cow‐side tests for diagnosing subclinical IMI.

Animals

One hundred and eleven dairy cows at dry‐off and 92 cows within 4–7 days postcalving.

Methods

Quarter foremilk samples were obtained and analyzed with a DeLaval cell counter (DCC, reference method), 1 ST, and CMT. The ST was run in a simulated cow‐side manner using milk at 37°C instead of 0–8°C as recommended by the manufacturer. Test performance for diagnosing IMI (DCC SCC >200,000 cells/mL) was evaluated by calculating the area under the receiver operating characteristic curve (AUC) and the kappa coefficient (κ) at the optimal cut‐point for each test. The effect of milk/reagent temperature also was evaluated.

Results

Compared to the reference method, the ST run in a simulated cow‐side manner had an AUC = 0.68 and κ = 0.24 at dry‐off, and AUC = 0.74 and κ = 0.40 in fresh cows. The CMT performed much better than the ST in diagnosing subclinical IMI with AUC = 0.88 and κ = 0.77 at dry‐off, and AUC = 0.87 and κ = 0.76 in fresh cows. The measured ST value decreased with increasing temperature of the milk/reagent mixture.

Conclusions/Clinical Importance

The ST is optimized for use on milk at 0–8°C and is therefore designed for on‐farm use on refrigerated milk samples. The ST is not suited for use as a cow‐side screening test for IMI because the milk temperature exceeds the recommended range for the test.     

Life history parameters and scale-cover surface area of Aonidiella aurantii are altered in a mating disruption environment: implications for biological control

BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale‐cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R₀) and intrinsic rate of increase (r_m) were significantly lower in the pheromone‐treated populations. The largest scale‐cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry     

Interannual and interdecadal variability in juvenile coho salmon (Oncorhynchus kisutch) diets in relation to environmental changes in the northern California Current

The feeding habits of juvenile coho salmon, Oncorhynchus kisutch, in the northern California Current were examined using samples from two different time periods (1980–85 and 1998–2003) of highly contrasting oceanographic conditions. The goal was to test the influence of interannual and interdecadal changes in taxonomic composition of prey, feeding intensity, and size spectra of teleost prey. Analyses were done for samples taken both early in the summer (June) shortly after the salmon enter the ocean, and also in late summer (September) following some ocean residency. Fish prey dominated coho salmon diets by weight during most years, but this trend was more pronounced during the 1980–85 sampling period. In terms of numerical composition, the diets were more variable on an interannual basis, but decapod larvae and euphausiids were important prey in most years. Pteropods and copepods were important prey during weak upwelling or El Niño years, whereas euphausiids were important during strong upwelling or otherwise highly productive years. Hyperiid amphipods comprised a substantial proportion of the diets only in 2000. Coho salmon showed highly significant differences in prey composition among years or between decades both in weight and numerical composition. The percentage of empty stomachs was highly variable by year in both June and September, but was significantly different only for September between decades. In contrast, an index of feeding intensity did not show many significant changes in either comparison. However, the relative size ratios for fish prey consumed were highly variable by year, and larger than average fish prey were consumed during 1998, leading to the highest feeding intensity observed.     

Study on the SNP of UCP1 Gene Exon 2 in Rabbit

In order to deeply understand the meat quality and provide the basic information and scientific proof for better heredity selection of rabbit.This experiment option New Zealand rabbit and Californian rabbit were used to construct own DNA pools, respectively for complete sequences amplification of exon 2 and part of intron 1 region of UCP1 gene, two-way sequencing the amplification of the product, BLAST and DNAStar analysis and determine the SNP of rabbit UCP1 gene.The results showed that six SNPs were found in UCP1 gene of the New Zealand rabbit:T135C, C232T, T332C, C360T, T550C and A560G, two synonymous mutation (T135C and C232T) and the other SNPs located in intron region respectively.Using RNA online prediction software forecast UCP1 gene RNA secondary structure prediction software minimum free energy changed from -917.51 kJ/mol to -866.10 kJ/mol for the polymorphisms led to the changes of RNA secondary structure.     

Comparing landscape scale vegetation dynamics following recent disturbance in climatically similar sites in California and the Mediterranean basin

A long line of inquiry on the notion of ecological convergence has compared ecosystem structure and function between areas that are evolutionarily unrelated but under the same climate regime. Much of this literature has focused on quantifying the degree to which animal morphology or plant physiognomy is alike between disjunct areas. An important property of ecosystems is their behavior following disturbance. Yet, this aspect of ecosystems has not been investigated in a comparative study of convergence. If different ecosystems are under similar environmental controls, then one would predict that the rates and patterns of response to disturbance would also be similar. The objective of this study is to compare landscape dynamics following disturbance using spatiotemporal models to quantify vegetation change in Mediterranean ecosystems found in California and Israel. We model the process of tree and shrub regeneration at the landscape scale in two similar study sites in Israel (Mount Meron) and California (Hasting Nature Reserve). During the periods studied (1964-1992 for Israel and 1971-1995 for California), average annual change in tree cover was 5 times larger in Israel than in California. Based on multiple regression models, differences were found in the relative importance of specific variables predicting vegetation change. In Hastings (California), initial tree cover accounted for most of the explained variability in 1995 tree cover (partial R² = 0.71), while in Meron (Israel), grazing type and intensity, topography indices, and initial vegetation each accounted for about a third of the explained variability. These findings support the notion that traits such as regeneration pattern and rate, both at the individual level and at the landscape level, were largely affected by the human land use history of the region.     

简评加州私有土地的木材管理

在加州,私人及私营公司拥有的生产性林地占４５％。为了收获木材,这些林地的业主需要持有执照的专业林业工作者准备一份详细的经营计划,该计划需经州政府广泛的审阅。这种经营计划往往耗资６０００～１２０００美元或更多的资金。计划的准备及州政府的审阅耗时６个月或更长的时间。林业工作者所作的决策受到法律、林地条件、经济状况和林地业主的目的等限制。林业实践法规对造林体系的选择及采伐后要达到 的更新量有详细的标准。     

Environmental associations of Pacific bluefin tuna (Thunnus orientalis) catch in the California Current system

We investigate the impact of oceanographic variability on Pacific bluefin tuna (Thunnus orientalis: PBF) distributions in the California Current system using remotely sensed environmental data, and fishery‐dependent data from multiple fisheries in a habitat‐modeling framework. We examined the effects of local oceanic conditions (sea surface temperature, surface chlorophyll, sea surface height, eddy kinetic energy), as well as large‐scale oceanographic phenomena, such as El Niño, on PBF availability to commercial and recreational fishing fleets. Results from generalized additive models showed that warmer temperatures of around 17–21°C with low surface chlorophyll concentrations (<0.5 mg/m³) increased probability of occurrence of PBF in the Commercial Passenger Fishing Vessel and purse seine fisheries. These associations were particularly evident during a recent marine heatwave (the “Blob”). In contrast, PBF were most likely to be encountered on drift gillnet gear in somewhat cooler waters (13–18°C), with moderate chlorophyll concentrations (0.5–1.0 mg/m³). This discrepancy was likely a result of differing spatiotemporal distribution of fishing effort among fleets, as well as the different vertical depths fished by each gear, demonstrating the importance of understanding selectivity when building correlative habitat models. In the future, monitoring and understanding environmentally driven changes in the availability of PBF to commercial and recreational fisheries can contribute to the implementation of ecosystem approaches to fishery management.