E. Coli

It is normal for E. coli to be present in the intestines of healthy animals. E. coli is a type of bacteria that is commonly found in the digestive tract of animals, including humans. While some strains of E. coli can cause illness, there are also many harmless strains that are a normal part of the gut microbiota. These harmless strains of E. coli play a role in digestion and other important functions in the intestines. Therefore, it is true that it is normal for E. coli to be present in healthy animals.

Edema disease of swine is caused by a toxin, which means that the statement "True" is correct. This disease is caused by a specific toxin produced by certain strains of Escherichia coli bacteria. The toxin affects the blood vessels, leading to fluid accumulation in various tissues of the body, including the brain, intestines, and skin. This can result in symptoms such as swelling, diarrhea, neurological signs, and even death in severe cases. Therefore, it is important to understand that the correct answer is "True" in this context.

EHEC, which stands for enterohemorrhagic Escherichia coli, is a strain of E. coli bacteria that produces Shiga toxin. This toxin is responsible for causing severe symptoms such as bloody diarrhea and kidney damage in infected individuals. Therefore, the statement that EHEC uses Shiga toxin is true.

E. coli is transmitted through the fecal-oral route, meaning that the bacteria from an infected person's feces can contaminate food, water, or surfaces, and then be ingested by another person. This can happen through improper hygiene practices, such as not washing hands after using the bathroom, or through consuming contaminated food or water.

Edema disease of swine is the likely cause of the symptoms described. Edema disease, also known as "gut edema" or "swine edema disease," is a bacterial infection caused by certain strains of Escherichia coli (E. coli) bacteria. The swollen eyelids and bloating are characteristic signs of this disease. Edema disease primarily affects young pigs, causing damage to the blood vessels and leading to fluid accumulation in different parts of the body, including the eyelids and abdomen. The central nervous system signs mentioned by the owner also align with the neurological effects of this disease. Porcine pleuropneumonia, braxy, and porcine synovitis are not associated with the specific symptoms described.

As calves mature, the K99 fimbriae, which are hair-like structures on the surface of bacteria, gradually lose their ability to stick to the villi, which are finger-like projections in the small intestine. This means that as calves grow older, the bacteria with K99 fimbriae are less likely to attach to the intestinal lining, reducing the risk of infection. Hence, the statement "As calves mature, the K99 fimbriae lose the ability to adhere to the villi" is true.

cAMP (cyclic adenosine monophosphate) is a molecule that is stimulated by LT (heat-labile enterotoxin). When LT stimulates the production of cAMP, it leads to secretory diarrhea. This is because cAMP activates the cystic fibrosis transmembrane conductance regulator (CFTR) channel, which results in increased secretion of chloride ions and water into the intestinal lumen, leading to diarrhea.

The given statement states that AEEC is equal to both EPEC and EHEC. This means that AEEC is equivalent to both EPEC and EHEC. Therefore, the correct answer is True.

The statement is true because LT (heat-labile enterotoxin) is a toxin that is produced only by swine strains of Enterotoxigenic Escherichia coli (ETEC). ETEC is a type of bacteria that causes diarrhea in humans and animals. LT is one of the main virulence factors of ETEC and is responsible for the watery diarrhea that occurs in infected individuals. Since LT is specific to swine strains of ETEC, it is not produced by other strains or types of bacteria. Therefore, the correct answer is true.

K99 fimbriae is the correct answer because it is a type of fimbriae that is found in Enterotoxigenic Escherichia coli (ETEC) and is known to affect calves. Fimbriae are hair-like appendages on the surface of bacteria that help them adhere to host cells and initiate infection. In the case of ETEC, the presence of K99 fimbriae allows the bacteria to attach to the intestinal lining of calves, leading to diarrhea and other gastrointestinal symptoms. K88 and K87 are other types of fimbriae found in ETEC, but they do not specifically target calves like K99 does.

ST is produced by both cattle and swine strains

ST (heat-stable toxin) stimulates the production of cGMP (cyclic guanosine monophosphate), which leads to secretory diarrhea. cGMP acts as a second messenger in the intestinal cells, causing an increase in chloride secretion and a decrease in sodium absorption. This imbalance in electrolyte transport disrupts the normal fluid absorption process in the intestine, resulting in the secretion of excess fluid into the intestinal lumen and ultimately causing secretory diarrhea.

Shiga toxin is the causative agent in edema disease of swine. Edema disease is a condition that affects pigs and is characterized by the presence of edema (fluid accumulation) in various tissues, particularly in the brain and subcutaneous tissues. Shiga toxin is produced by certain strains of Escherichia coli bacteria, specifically those belonging to the Shiga toxin-producing E. coli (STEC) group. When these bacteria infect pigs, they release Shiga toxin, which damages blood vessels and causes fluid accumulation, leading to the symptoms of edema disease. Therefore, Shiga toxin is responsible for causing edema disease in swine.

EPEC (Enteropathogenic E. coli): This type is known to cause diarrhea in infants and neonates. It attaches to the intestinal lining and disrupts the microvilli, leading to diarrhea.

ETEC (Enterotoxigenic Escherichia coli) is a type of bacteria that causes severe diarrhea by producing toxins. While ETEC can damage the intestinal lining, it does not specifically destroy the villi. Villi are small finger-like projections in the small intestine that increase the surface area for nutrient absorption. The damage caused by ETEC primarily affects the function of the intestine rather than destroying the villi completely. Therefore, the statement "ETEC destroy the villi that they colonize" is false.

E. coli O:157H:7 refers to a specific strain of E. coli bacteria that can cause a severe illness known as Hemolytic Uremic Syndrome (HUS) in humans. HUS is a condition characterized by the destruction of red blood cells, kidney damage, and the formation of blood clots. It can lead to serious complications such as kidney failure and even death. Therefore, the answer "Hemolytic Uremic Syndrome" accurately represents the meaning of E. coli O:157H:7 causing HUS in humans.

Weanling diarrhea in pigs is caused by the K88 fimbriae type. Fimbriae are hair-like structures on the surface of bacteria that help them attach to host cells. In the case of weanling diarrhea, the K88 fimbriae allow the bacteria to attach to the lining of the pig's intestine, leading to diarrhea.

Shiga toxin primarily affects the brain, eye lids, mesentery, and stomach. This toxin is produced by certain strains of bacteria, such as Escherichia coli (E. coli), and can cause severe gastrointestinal symptoms like diarrhea and abdominal pain. Additionally, it can lead to neurological complications, such as seizures and hemolytic uremic syndrome (HUS), which can affect the brain. The toxin can also cause inflammation and damage to the eye lids, mesentery (the tissue that connects the intestines to the abdominal wall), and the stomach.

AEEC stands for Attaching and Effacing E. coli. This term refers to a specific type of E. coli bacteria that attaches to the intestinal lining of its host and causes damage by effacing or erasing the microvilli on the surface of the cells. This attachment and effacement process allows the bacteria to establish a foothold in the host's gut and cause various gastrointestinal symptoms.