Animal mortality

About: Animal mortality is a research topic. Over the lifetime, 526 publications have been published within this topic receiving 14887 citations.

Abstract 10378: Characterization of Changes in Cardiac Structure and Function in Mice Treated With Anthracyclines Using Serial Cardiac Magnetic Resonance Imaging

Abstract: Introduction: Anthracyclines are a standard chemotherapeutic agent. However, the anthracyclines are associated with a late reduction in left ventricular ejection fraction (LVEF) and heart failure. Pathologically, anthracycline-induced cardiotoxicity (AIC) is characterized by the development of cardiac edema and fibrosis and cardiac magnetic resonance (CMR) is the gold-standard imaging technique for edema and fibrosis. Hypothesis: We hypothesized that a) cardiac edema and fibrosis would be detected by CMR after anthracyclines and b) edema and fibrosis would provide prognostic information. Methods: We performed a longitudinal CMR and histological study of 45 wild-type mice randomized to doxorubicin (DOX, n=30, 5 mg/kg/week for 5 weeks) or placebo (n=15). Measurements were performed at baseline, 5, 10, and 20 weeks after DOX or placebo. Measures of interest were LVEF, myocardial edema and fibrosis. Edema was assessed by T2 mapping, fibrosis by calculating the extracellular volume (ECV) from pre- and post-contrast T1 measurements. Results: In DOX-treated mice vs. placebo, myocardial edema at 5 weeks was increased (T2 values of 32±4 vs. 21±3 ms, P Conclusions: Our data suggest that, in mice, CMR can detect the early increase in edema and sub-acute increase in fibrosis after anthracyclines, that an increase in edema precedes a reduction in LVEF, that the increase in edema and fibrosis are linked and both are predictive of late animal mortality.

Small Stock Mortality Composting

Abstract: Why Compost Sheep and Goat Mortality? All livestock producers encounter mortality. Goat and sheep operations may experience annual mortality losses of up to 10% of young before weaning and 5% of adult breeding animals. For a producer with 30 breeding females, two-thirds of whom have twins, this would mean a loss of about 5 young and 2 adults. Severe disease or internal parasite outbreaks may add to this loss. Finding appropriate carcass disposal methods can be challenging. The State of Oklahoma Department of Agriculture, Food and Forestry lists five acceptable options for animal carcass disposal: 1) rendering, 2) burial, 3) incineration, 4) landfills, and 5) composting. Finding a rendering service for sheep and goats is difficult. Since July 1, 2006 there has been no rendering facility in Oklahoma that accepts goat carcasses or offal (Dan Parrish, Director, Agric. Env. Mgt. Serv. Div., Oklahoma Dept. of Agric., personal communication). Burial may be expensive if proper equipment must be rented. Further, there are rules on burial that must be followed. Carcasses may not be buried less than 1 foot above flood plains or within 2 feet of the water table or bedrock. Burial cannot take place within 300 feet of water sources, houses, public areas or property lines and carcasses must be covered with a minimum of 2.5 feet of soil. The cost to purchase and operate an incinerator is not economical for most producers. Not all landfills accept carcasses, and those that do charge disposal fees. Composting is an inexpensive, environmentally friendly method of disposing of animal mortality that is commonly used in the poultry and swine industries. In the same way that microorganisms degrade vegetative waste and turn it into a rich soil amendment, animal carcasses can be turned into an organic matter-rich material that can be spread on pastures and other agricultural land. When properly done, animal composting generates no odor and temperatures generated during composting are high enough to kill most pathogens. However, animals suspected to have died from severe zoonotic diseases, i.e., diseases that can be passed to humans, such as anthrax, should not be composted. Sheep and goats that die from scrapie should never be composted as the agent responsible for this neurological disease is not killed at common compost pile temperatures. However, for most cases of mortality, composting is a safe, low-cost alternative to other carcass disposal options.

Bozeman Pass Wildlife Pre- and Post-Fence Monitoring Project

Abstract: The Bozeman Pass transportation corridor between Bozeman and Livingston, Montana, includes Interstate-90, frontage roads, and a railroad. The highway supports 8,000-12,000 daily vehicles during the winter and 10,000 to 15,000 daily vehicles during the summer. The interstate has essentially become a barrier and hazard to animal movements in the Bozeman Pass area. To determine the extent of the animal-vehicle conflicts and where conflicts may best be mitigated, Craighead Environmental Research Institute (CERI) began collecting field data on Bozeman Pass in 2001. Data analysis led to recommendations to incorporate approximately 2 miles of wildlife fencing, cattle guards and landscaping design modifications into the reconstruction of a Montana Rail Link (MRL) overpass. These recommendations were accepted by the Montana Department of Transportation (MDT) and MRL in 2005 and a wildlife fence and four jump-outs were constructed in 2007. Adding relatively low cost wildlife mitigation measures to existing highway projects are effective in increasing highway permeability and reducing animal mortality, and could be incorporated into the Obama infrastructure initiative. Data on wildlife crossings and animal-vehicle collisions (AVC) were collected before and after installation of the fencing to evaluate if the fencing reduces animal-vehicle collisions, and to determine animal movements under the highway via existing culverts and the MRL overpass. Data collection includes seven tasks, as follows: (1) Road kill surveys between Bozeman and the Jackson Creek interchange. (2) Track bed monitoring of wildlife movements under the MRL bridge. (3) Remote camera monitoring of wildlife movements at fence ends. (4) Infrared counter monitoring of wildlife movements at jump-outs. (5) Track bed monitoring of wildlife movements at fence ends and jump-outs. (6) Remote camera monitoring of wildlife movements in two culverts at east end of fence. (7) Opportunistic snow tracking under MRL bridge and in fenced area. Power analyses (power = 0.8; α = 0.05) indicated three to five years of post-fencing study would be optimal in order to make reasonable quantitative comparisons between the pre- and post-fencing ungulate-vehicle collision (UVC) data. This presentation reports on 2 years of data. Nearly 2,000 animals have been killed along 23 miles of Interstate 90 from 2001 - June 2009. Since the installation of the wildlife fence about 1.5 miles long, two white-tailed deer has been killed within the fenced area and three have been killed at the fence ends. There has not been an increase in animal-vehicle collisions (AVC) at the ends of the fence. Preliminary results indicate an increased use of underpasses and culverts by wildlife. Costs for this project were much lower than new wildlife crossing structures since the fencing was added on to a structure replacement project for an existing underpass. More wildlife appears to travel through the rebuilt underpass as well as through other existing crossing structures (culverts and county road bridge). This suggests that fencing alone can be added to help direct animals through existing structures. Wildlife fencing leading to existing crossing structures is a cost-effective method of reducing AVC and thus reducing risk to motorists as well as increasing connectivity for wildlife. Design improvements in jump-outs and fence-ends will be discussed.

Modelling feedlots using the MEDLI model framework

Abstract: Model for Effluent Disposal using Land Irrigation (MEDLI) is a biophysically-based daily time-step model released in 1996 to facilitate designing effluent irrigation schemes. The model simulates a waste stream generator producing effluent that is treated in a pond system with a wet weather storage pond from which the effluent is irrigated as required to an area of land growing vegetation (Gardner et al. 1996). To complement the existing waste stream generator options, MEDLI is undergoing further development to include rainfall-dependent waste streams, including that generated by rainfall wash-off from feedlot production pens. This will facilitate MEDLI's use for designing effluent irrigation schemes associated with feedlots. The feedlot pen model attempts to model the complex dynamic processes within feedlot production pens that impact on the quantity and quality of runoff using a daily time-step mass balance approach. An early description of the feedlot model for MEDLI, focusing on runoff quantity, was provided by Atzeni et al. (2001). Since then, the hydrology component has been substantially improved to generate daily surface and sub-surface pad moisture output for use in predicting odour emissions (Atzeni et al. 2015), as well as runoff quantity and quality. In this paper, we present the modelling approach and model algorithms used to simulate the waste stream from the feedlot production pens. Supporting references are detailed in Atzeni et al. (2015). The MEDLI feedlot pen model is designed to simulate a modern feedlot yard with equal-sized production pens having adequate slope, and operating within the recommended Australian guidelines. Cattle can be designated to up to four markets, with market-specific entry and exit weights, daily weight gain, proportion of total herd designated, and proportion of pens occupied. Daily calculations are performed on a pen by pen basis, to model the key processes of herd dynamics, manure (faeces+urine) production, assimilation of the fresh manure into the pad, pen hydrology and pen cleaning. Herd dynamics include modelling animal mortality and pen stocking. When animals in a pen reach the exit weight for their market type, the model flags that the pen is vacant and drafts another mob (of the same market type) into another vacant pen if possible, or else the same pen. Manure production relies on BEEFBAL (QPIF 2004) or similar model to provide the market-specific annual manure production (total solids, volatile solids, total nitrogen, total phosphorus, salts and water) of each animal which is then used to determine the solids, nutrient, salt and water loading onto the manure pad. Assimilation of the fresh manure into the pad uses a two-layer model for the manure pad, assuming no loss of water or solids below the lower layer of the pad. The two layers capture the dynamics of pad hydrology and composition, including the impacts of rainfall, evaporation, animal stocking, manure accumulation, volatile solids decay, pen cleaning, runoff and manure erosion during runoff. Pens are cleaned at intervals to remove the excess manure, and involve considering the specified minimum number of days since a pen is cleaned, the pen's pad moisture content, pad depth, and the number of pens being cleaned each day. By modelling these processes, the fate of the nutrients, salts and solids from the manure pads is simulated as shown in Figure 1.Validation of the feedlot pen model hydrology was undertaken using four field-collected data sets from three South East Queensland feedlots. The prediction of runoff quantity appears closely correlated with measured data. However, the runoff quality predictions require calibration of the total nitrogen, total phosphorus, and salt runoff concentrations with actual or expected holding pond chemistry. Data collection is in progress to allow further testing and validation of the feedlot pen module. Copyright © 2019 The Modelling and Simulation Society of Australia and New Zealand Inc. All rights reserved.