Animal mortality

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

Livestock Mortalities Burial Leachate Chemistry after Two Years of Decomposition

Abstract: A study was performed to determine the chemical composition of animal mortality leachate arising in a burial setting. Three species of livestock were used: bovine, swine and poultry. Leachate collected from lined burial pits over two years of decomposition was analyzed for major and minor ions. Livestock mortality leachate contains on average, concentrations of 12,600 mg/L of ammonium-N, 46,000 mg/L alkalinity (as bicarbonate), 2,600 mg/L chloride, 3,600 mg/L sulphate, 2,300 mg/L potassium, 1,800 mg/L sodium, 1,500 mg/L phosphorus along with relative lesser amounts of iron, calcium and magnesium. Maximum concentrations of select samples had concentrations of ammonium-N and bicarbonate up to 50% higher than these average values. The pH of the leachate was near neutral. In comparison to earthen manure storages and landfills, the strength of the leachate was 2-4 times higher.

Characteristics of Wolf Attacks on Moose in Mount McKinley National Park, Alaska

Abstract: ... The present paper describes attack patterns and wounds inflicted on moose ( Alces alces ) by wolves ( Canus lupus ) and comments on attacks by grizzly bears ( Ursus arctos ) on ungulates in Mount McKinley National Park, Alaska. ...

A syngeneic hepatocellular carcinoma model rapidly and simply prepared using a hydrodynamics-based procedure

Abstract: A rapid and simple method to deliver tumor cells into the liver by intravenous injection of a large volume of tumor cell solution at a high velocity has been developed for use in the preparation of hepatic cancer mouse models. With this hydrodynamics-based procedure, there was a 100% tumor occurrence in the liver and lungs of mice at 2 and 3 weeks, respectively. In contrast, mice injected using a non-hydrodynamics-based system showed no tumor occurrence in the liver 3 weeks after injection, although tumors were present in the lungs. The technique may be useful in the rapid development of hepatic cancer mouse models and in reducing animal mortality during model preparation.

How thyroid hormones and their inhibitors affect cartilage growth and shape in the frog Xenopus laevis.

Abstract: Understanding how skeleton changes shape in ontogeny is fundamental to understanding how its shape diversifies in phylogeny. Amphibians pose a special case because their jaw and throat skeleton consists of cartilages that are dramatically reshaped midway through life to support new feeding and breathing styles. Although amphibian metamorphosis is commonly studied by immersing larvae in thyroid hormones (TH), how individual cartilages respond to TH is poorly understood. This study documents the effects of larval stage and TH type (T4 vs. T3), dose and deprivation on the size, shape and morphogenesis of the lower jaw and ceratohyal cartilages in the frog Xenopus laevis. It uses thyroid inhibitors to isolate the effects of each hormone at specific concentrations. It also deconstructs the TH responses into the effects on individual dimensions, and uses measures of percent change to eliminate the effects of body size and growth rate variation. As stage increases, T4 and T3 responses become increasingly similar to each other and to natural remodeling; the differences at low and intermediate stages result largely from abnormal responses to T3. Most notably, the beak-like lower jaw commonly observed at the lowest stage in other studies results largely from arrested growth of cartilage. TH responses are superimposed upon the growth typical for each stage so that cartilages can attain postmetamorphic shapes through dimensional changes that exceed those of natural metamorphosis. Using thyroid inhibitors alters the outcome of TH-induced remodeling, and T4 has almost the same capacity to induce metamorphic shape changes as T3. The results have implications for understanding how the starting shapes of larval elements affect morphogenesis, how chondrocytes behave to change cartilage shape, and how intracellular processing of TH might contribute to interspecific differences in shape change. Also, the data on animal mortality and which stages and doses most closely replicate natural remodeling have practical value for researchers who treat Xenopus tadpoles with TH.