impaction.docx

**Impaction** **a- Rumen impaction** is an accumulation of the indigestible materials in the rumen which interferes with the flow of ingesta leading to distension of the rumen and passing of scanty or no feces. The effects of these indigestible foreign bodies (IFB) \[were polythene bags, metallic o...

**Impaction** **a- Rumen impaction** is an accumulation of the indigestible materials in the rumen which interferes with the flow of ingesta leading to distension of the rumen and passing of scanty or no feces. The effects of these indigestible foreign bodies (IFB) \[were polythene bags, metallic objects, fibres and hair balls, plastic bags, nylon rope\] on the nutrition and health aspect of cattle has not been elucidated suggested that toxic chemicals and pesticides have the potential to disrupt beneficial and necessary biological systems which threaten the biosecurity. The indigestible foreign bodies (IFB) were more happened in females than males and 91.02% of cases were noticed in adult cattle. **The clinical signs** observed were pale mucous membrane, absence of rumination and reduced ruminal motility. Absence of stratification was observed in all the affected animals. Rectal examination revealed pellet mucous coated dung. Complete cessation of rumination, impacted rumen, atony, reduced rumen motility. It can be concluded that rumen impaction mainly causes depression, anorexia, reduced milk yield, abdominal distension and loss of defecation. Highly significant decrease in the haemoglobin, PCV and total erythrocytic count with leukocytosis and Normocytic normochromic anaemia hypoproteinemia, hypoalbuminaemia, hypocalcaemia were noticed in some of the clinical cases. *Production disease Dr. Tamara Natik Dawood* Neutrophilia may be due to dietary deficiency, presence of foreign bodies and sloughing, stunting, erosions, inflammatory response and the hyperplasia due to the pressure on the wall of the rumen caused by the foreign bodies. Hypoproteinemia and hypoalbuminaemia could be due to dietary malnutrition and stress reaction to infection. Hypocalcaemia might de due to dietary deficiency and failure of calcium absorption due to reduced ruminal motility. Hypoglycaemia might be due to inadequate intake of feed. Hypophosphatemia noticed in the affected animals might be associated with shortage of feeds, perhaps especially of minerals and vitamins. The results suggest that the rumen impaction in stray cattle might be due to scavenging on refuse dumps and that the blood biochemical changes, along with clinical signs, might be of some diagnostic assistance. **b-Impaction of the abomasum** develops in pregnant beef cows during cold winter months when cattle have decreased water intake and are fed poor-quality roughage. Impaction also has been seen in feedlot cattle fed a variety of mixed rations containing chopped or ground roughage (straw, hay) and cereal grains and in late-pregnancy dairy cows on similar feeds. **Etiology and Pathogenesis** The cause of dietary abomasal impaction is due to consumption of excess roughage low in both digestible protein and energy. Impaction with sand can occur if cattle are fed hay or silage on sandy soils, or root crops that are sandy or dirty. Outbreaks may affect up to 15% of all pregnant cattle on individual farms when the ambient temperature drops to (--2°C) or lower for several days. The cause in postparturient dairy cows is probably related to abomasal hypomotility. The pathogenesis is related to diet. When the abomasum becomes impacted, sub-acute obstruction of the upper GI tract develops. Ions of hydrogen and chloride are continually secreted into the abomasum in spite of the impaction and alkalosis with hypochloremia result. Varying degrees of dehydration develop, because fluids are not moving beyond the abomasum into the duodenum for absorption. Sequestration of potassium ions in the abomasum results in hypokalemia. *Production disease Dr. Tamara Natik Dawood* Dehydration, alkalosis, electrolyte imbalance and progressive starvation are seen. Impaction of the abomasum may be severe enough to cause irreversible abomasal atony. **Clinical Findings and Lesions** Complete anorexia, scant feces, moderate distention of the abdomen, weight loss and weakness are usually the initial signs of dietary abomasal impaction. Body temperature is usually normal but may be subnormal during cold weather. A mucoid nasal discharge tends to collect at the external nares and on the muzzle; the muzzle is usually dry and cracked, caused by both the failure of the animal to lick its nostrils and the effects of dehydration. The heart rate may be increased and mild dehydration is common. Most often, the rumen is static and distended with dry contents, but it may contain excess fluid if the cow has been fed finely ground feed. The pH of the ruminal fluid is usually normal (6.5--7). Protozoal activity in the rumen ranges from normal to a marked reduction in numbers and activity. The impacted abomasum is usually in the right lower quadrant on the floor of the abdomen. Deep palpation and strong percussion of the right flank may indicate the presence of a large, firm mass (impacted abomasum) and elicit a grunt (as is common in acute traumatic reticuloperitonitis), probably because of distention of the abomasum and stretching of its serosa. Severely affected cattle die 3--6 days after the onset of signs. The abomasum ruptures in some cases and death from acute, diffuse peritonitis and shock occurs in a few hours. In sand impaction, there is considerable weight loss, chronic diarrhea with sand in the feces, weakness, recumbency and death in a few weeks. Metabolic alkalosis, hypochloremia, hypokalemia, and hemoconcentration are common as are total and differential WBC counts within the normal range. At necropsy, the abomasum is commonly enlarged (up to 8 times normal size) and impacted with dry rumen-like contents. The omasum may be similarly enlarged and impacted. The rumen is grossly enlarged and filled with dry contents or fluid. The GI tract beyond the pylorus is characteristically empty and has a dry *Production disease Dr. Tamara Natik Dawood* appearance. Varying degrees of dehydration and emaciation are also present. If the abomasum has ruptured, lesions of acute diffuse peritonitis are present. **Diagnosis** Clinical diagnosis of dietary abomasal impaction is based on the nutritional history, clinical evidence of impaction and laboratory results. Impaction of the abomasum as a complication of traumatic reticuloperitonitis usually is seen in late pregnancy and commonly only in one animal. The rumen is enlarged and may be hypermotile (early) or atonic (late). In many cases, it is impossible to distinguish between the two causes of impacted abomasums. Right flank laparotomy may be necessary to explore the abdomen for peritoneal lesions. **Treatment** The challenge is to recognize the cases of dietary abomasal impaction that will respond to treatment and those that will not, ie, to determine those animals that should be slaughtered immediately for salvage. Cows that are weak have a severely impacted abomasum and have a marked tachycardia (100--120 bpm) are poor treatment risks. Medical treatment usually requires a confirmed diagnosis via right-side laparotomy. In cows that are treated, the metabolic alkalosis, hypochloremia, hypokalemia and dehydration should be corrected. Lubricants can be used in an attempt to move the impacted material; it is necessary to empty the abomasum surgically only in cattle with severe impaction. Balanced electrolyte solutions are infused IV continuously for up to 72 hr at a daily rate of 80--120 mL/kg. Some cows respond well to this therapy and begin ruminating and passing feces in 48 hr. Mineral oil should be administered at 4 L/day for 3 days. Additionally, dioctyl sodium sulfosuccinate (DSS) can be injected once into the abomasum during standing right flank laparotomy at 60--100 mL of a 25% solution for a 450-kg animal. This dose rate should not be administered IP because DSS kills rumen protozoa. A beneficial response cannot be expected in \