How do horses kidneys work?

Equine Renal Physiology

The equine kidney is responsible for maintaining the body's water and electrolyte balance, as well as filtering out waste products from the blood. The kidneys are located in the retroperitoneal space, just below the last rib. Each kidney is about the size of a human fist and weighs approximately 1.5-2 pounds.

The kidneys are made up of millions of tiny filtering units called nephrons. Each nephron consists of a renal corpuscle and a renal tubule. The renal corpuscle is where blood is filtered, and the renal tubule is where the filtrate is reabsorbed and concentrated into urine.

Renal Filtration

Renal filtration is the process by which blood is filtered to create urine. It occurs in the renal corpuscle, which consists of a glomerulus and a Bowman's capsule.

The glomerulus is a network of small blood vessels that is located inside the Bowman's capsule. The Bowman's capsule is a cup-shaped structure that surrounds the glomerulus.

As blood flows through the glomerulus, water and solutes are forced out of the blood and into the Bowman's capsule. This process is called ultrafiltration.

The filtrate that is created in the Bowman's capsule contains water, electrolytes, glucose, amino acids, and other solutes.

Renal Tubular Reabsorption

Renal tubular reabsorption is the process by which the kidneys reclaim water and solutes from the filtrate and return them to the blood. It occurs in the renal tubules.

The renal tubules are long, convoluted tubes that lead from the Bowman's capsule to the collecting ducts.

As the filtrate flows through the renal tubules, water and solutes are reabsorbed into the blood. The amount of water and solutes that are reabsorbed is regulated by hormones such as antidiuretic hormone (ADH) and aldosterone.

Renal Tubular Secretion

Renal tubular secretion is the process by which the kidneys actively transport solutes from the blood into the filtrate. It occurs in the renal tubules.

Some of the solutes that are secreted into the filtrate include hydrogen ions (H+), potassium ions (K+), and creatinine.

Renal tubular secretion helps to maintain the body's acid-base balance and electrolyte balance.

Urine Concentration

The final step in urine production is urine concentration. Urine concentration occurs in the collecting ducts.

The collecting ducts are long, straight tubes that lead from the renal tubules to the renal pelvis.

As the filtrate flows through the collecting ducts, water is reabsorbed into the blood, and the filtrate becomes more concentrated.

The amount of water that is reabsorbed is regulated by ADH. ADH causes the collecting ducts to become more permeable to water, which allows more water to be reabsorbed into the blood.

The final product of urine production is urine. Urine is a clear, yellow liquid that is composed of water, electrolytes, and other solutes. Urine is stored in the bladder and is periodically expelled from the body through urination.