Showing papers on "Animal mortality published in 2004"

Multiple Ebola Virus Transmission Events and Rapid Decline of Central African Wildlife

Abstract: Several human and animal Ebola outbreaks have occurred over the past 4 years in Gabon and the Republic of Congo. The human outbreaks consisted of multiple simultaneous epidemics caused by different viral strains, and each epidemic resulted from the handling of a distinct gorilla, chimpanzee, or duiker carcass. These animal populations declined markedly during human Ebola outbreaks, apparently as a result of Ebola infection. Recovered carcasses were infected by a variety of Ebola strains, suggesting that Ebola outbreaks in great apes result from multiple virus introductions from the natural host. Surveillance of animal mortality may help to predict and prevent human Ebola outbreaks.

A Review of Literature Concerning Odors, Ammonia, and Dust from Broiler Production Facilities: 2. Flock and House Management Factors

Abstract: SUMMARY Confinement buildings are one of the most likely sources of odor in a broiler operation. The buildings must be ventilated, either mechanically with fans or relying on natural airflow, to prevent animal mortality and enhance animal health. Consequently, odors generated within the building are carried to the surrounding environment by the ventilation system. This review addresses the management of those factors that affect the production and removal of odorants in a broiler production operation. Published literature does not specifically discuss odor generation within broilerhouses.Severalstudiesdealwithammonia(anodorantgas)orparticulatematter(apollutant thought to carry odorant gases) emissions in broiler houses. These studies are discussed and inferences are made about the generation of odors under similar conditions. Conditions that lead to higher moisture in the litter tend to increase ammonia release, and by inference, more odorant release. Higher litter moisture is presumed to encourage greater microbial degradation ofuric acidexcreted bythe birdsinto thelitter andrelease moreammonia. Evaporative coolers may produce excess water droplets that fall to the litter rather than evaporate to cool the incoming air. Broiler houses that use misting systems generally have higher moisture content in the litter at the inlet end of the house. Either type of evaporative cooling system may also reduce litter drying rates by increasing humidity levels within the house. At the other extreme, low litter moisture could lead to the production of more particulate matter (i.e., dust), a pollutant that can transport odors to the atmosphere. The optimum litter moisture content that can minimize odorant and dust release is somewhere within the range of 25 to 35%, but exact values for optimum balance depend on numerous house-specific conditions. Changes in dietary nutrient levels can alter the production of ammonia by varying the amount of nitrogen available; however, most currently researched methods show negative impacts on productivity. Management of watering devices is critical to controlling litter moisture. Proper water equipment maintenance and operation are part of daily house management strategies to control litter moisture and, therefore, dust and odor.

Effects of sodium hypochlorite and ozone on healing of intestinal anastomosis in simulated strangulation colorectal obstruction.

Abstract: Strangulation colorectal obstruction was modeled in 60 Wistar rats. Necrotic segment of the intestine was resected under conditions of peritonitis and end-to-end intestinal anastomosis was performed on a PCV catheter conducted through the anus. Sodium hypochlorite and ozone solution were used for sanitation of the abdominal cavity and intestinal lavage, and the intestinal anastomosis was coated with Ozonide (ozonized oil). The use of physicochemical methods notably reduced the incidence of postoperative pyoinflammatory complications, incompetence of intestinal anastomosis sutures, and animal mortality.

Merogony of Toxoplasma gondii (Apicomplexa: Coccidia) and its effect on the mortality and histopathology in the house mouse Mus musculus.

Abstract: Merogonic stages of Toxoplasma gondii, their effects on the mortality and histopathological changes in the orally-inoculated male house mice Mus musculus with low and high doses (LD&HD) of T. gondii sporulated oocysts was investigated. The mortality percentage in LD group was 16%, 20%, 28% and 72%, while that in HD group was 36%, 56%, 72% and 100% in the 1st-4th week, respectively. Meanwhile, the maximum mortality percentage of the control group reached 6%. The histopathological changes induced by the parasite in different organs such as kidneys, liver, brain, spleen, heart, lungs and testes were discussed.

Change and role of heme oxygenase-1 in injured lungs following limb ischemia/reperfusion in rats.

Abstract: Objective: To study the change and role of heme oxygenase-1 (HO-1) in injured lungs following limb ischemia/reperfusion in rats. Methods: A total of 96 healthy male Sprague-Dawley rats, weighing 250-300 g, were used in this study. Hind limb ischemia was made on 40 rats through clamping the infrarenal aorta for 2 hours with a microvascular clip, then limb reperfusion for 0, 4, 8, 16 and 24 hours (n=8 in each time point) was performed, respectively. Other 8 rats undergoing full surgical operation including isolation of the infrarenal aorta without occlusion were taken as the sham operation group. Lung tissues were obtained from the 48 animals and Northern blotting and Western blotting were employed to measure the changes of HO-1 mRNA and protein expression, respectively. Immunohistochemistry technique was used to determine the cell types responsible for HO-1 expression after limb ischemia/reperfusion. Then hind limb ischemia was made on other 12 rats through clamping the infrarenal aorta for 2 hours with a microvascular clip, among whom, 6 rats were given zinc protoporphyrin (ZnPP), an inhibitor of HO. Then limb reperfusion for 16 hours was performed on all the 12 rats. And other 12 rats underwent full surgical operation including isolation of the infrarenal aorta without occlusion, among whom, 6 rats were then given ZnPP. Then lung tissues were obtained from the 24 animals and lung injury markers, lung histology, polymorphonuclear leukocyte (PMN) count and malondialdehyde (MDA) content were detected, respectively. HO activity was determined through measuring the carboxyhemoglobin (COHb) level in artery blood with a CO-oximeter after limb ischemia/reperfusion. And the animal mortality was observed on the other 24 rats. Results: Northern blotting analysis showed that HO-1 mRNA increased significantly at 4 hours after reperfusion, peaked at 16 hours, and began to decrease at 24 hours. In contrast, no positive signal was observed in the sham and simple ischemia animals. Increased HO-1 mRNA levels were accompanied by similar increases in HO-1 protein. Lung PMNs and MDA content increased significantly at 4, 8, 16 and 24 hours after reperfusion, compared with the sham controls (P 0.001), while they decreased in rats with reperfusion for 16 hours when compared with rats with reperfusion for 4 hours (P 0.001). Immunohistochemical studies showed that HO-1 was expressed in a variety of cell types, including the airway epithelia, alveolar macrophages and vascular smooth muscular cells. The blood COHb level and animal mortality increased significantly after limb ischemia/reperfusion compared with the sham controls (P 0.001). ZnPP administrated to the ischemia/reperfusion animals led to a decrease in the COHb level and an increase in lung PMN number, MDA content and animal mortality (P 0.001 compared with ischemia/reperfusion group), and the lung injury was aggravated. Conclusions: Limb ischemia/reperfusion up-regulates pulmonary HO-1 expression, which serves as a compensatory protective response to the ischemia/reperfusion-induced lung injury in rats.

Topical sirolimus for prevention of subglottic stenosis in a rabbit model

Abstract: Objectives: To utilize an established animal model to test the ability of topical sirolimus, a macrolide immunosupressant, to prevent or reduce subglottic stenosis. Methods: Pasturella-free New Zealand white rabbits were injured in the subglottic mucosa by a cricoid split procedure and laser. Each of the rabbits in 3 groups received either saline, mitomycin, or sirolimus atomized by direct laryngoscopy to the injured mucosa every 4 days over 3 subsequent weeks. The animals were subsequently sacrificed and the larynges examined grossly and histologically. Results: Our model predictably resulted in inflammation and subglottic scarring in controls (saline). Mitomycin inhibits subglottic scarring but prevents epithelialization and resulted in early rabbit mortality. Sirolimus prevents scar formation, inflammation, does not interfere with epithelialization, and did not result in animal mortality. Conclusion: We believe that the animal model described above is an excellent model for studying subglottic stenosis. The histologic changes within the lamina propria of the injured airway demonstrate chronic inflammatory cell infiltrate and fibroplasia. These findings are quite similar to the changes that occur within normal skin with hypertrophic scarring and keloid formation. Sirolimus is a potent inhibitor of key elements of fibrosis: namely fibroblast proliferation and production of growth factors that stimulate the laying down of wound matrix and collagen formation. Our preliminary study suggests that sirolimus may be an effective topical agent that will inhibit tissue fibrosis and subglottic scarring.

Isovolämische Hämodilution mit HAES und bovinem Hämoglobin verbessert die pankreatische MikroZirkulation, den pankreatischen Gewebssauerstoffpartialdruck und bietet einen Überlebensvorteil bei schwerer akuter Pankreatitis im Schweinemodell

Abstract: To avoid the progression from mild edematous acute pancreatitis to the severe necrotising form, one therapeutic option is to improve pancreatic microcirculation. The aim of the study was to evaluate the influence of isovolemic hemodilution and additional oxygen supply (bovine hemoglobin) on pancreatic microcirculation, tissue oxygenation and survival in severe acute experimental (porcine) pancreatitis. Methods: 39 pigs (25 - 30 kg BW) were anesthetised and catheters were placed. After midline laparotomy severe acute pancreatitis was induced (intraducatal injection of glycodeoxycholic acid (0,4 ml/kg BW; 10 mmol/1) and cerulein i.v. (5 microg/kg BW/h)). After 75 minutes animals were randomised into three groups (each n = 13): 1: isovolemic hemodilution (IHD) with hydroxyethyl starch (HES) and additional bovine hemoglobin (Oxyglobin, Biopure, MD); 2: IHD with HES and 3: IHD with Ringer’s solution. Then IHD was started until a hematocrit of 15% (50% of initial hematocrit) was reached. Pancreatic microcirculation was monitored using a laser-doppler scanner (Laser Perfusion Imager, Moor, Millway, UK) and tissue oxygenation of the pancreas (tpO2) was measured using a Licox catheter (GMS, Kiel, FRG). After 6 hours, catheters were removed, the abdomen was closed and animals were extubated. After 6 days, surviving animals were sacrificed. Results: In animals of group 1 pancreatic microcirculation improved over the observational period when compared to group 3 (mean difference of area under the curve: 510,8 (SE 111,5) (p < 0,001). Also, tpO2 improved in HBOC-200 treated animals (102,6 (SE 16,4) vs. group 3 and 76,7 (SE 15,9) vs. group 2; both p < 0,001). Ten animals survived in group 1, while 8 animals in group 2 and only 2 animals in group 3 were alive at the end of the observational period (p = 0,001 Kruskal-Wallis Test). Conclusion: Improved rheology and additional supply of oxygen lead to improved pancreatic microcirculation and better tissue oxygenation in severe acute porcine pancreatitis. This novel therapeutic strategy decreased animal mortality.