Systems of Filtration

Size: px

Start display at page:

Download "Systems of Filtration"

Myron Allison
5 years ago
Views:

1 Systems of Filtration EQS 110

2 Protecting & Filtering Our previous lecture focused on two different body systems that shared a common goal communicating with the body. In this lecture, we again will discuss two different body systems that look provide the horse with a means to an essential life function filtration. The lymphatic and urinary systems, while different in structural components, both serve to maintain fluid balance and cellular health within the body. Table of Contents The Lymphatic System... 3 Lymphatic Circulation... 3 Lymphatic Filtration... 4 Lymphatic Flow... 5 Other Lymphatic Tissues... 5 Management of the Lymphatic System... 6 The Urinary System... 7 Kidneys... 7 Filtration... 7 Effect on Exercise... 8 Bladder... 8 Management of the Urinary System... 9 Self-Knowledge Checks Answers Glossary... 12

The Lymphatic System The lymphatic system is an extensive system of vessels and nodes that play a crucial role in maintaining fluid balance and cellular health within the body.

The main functions of the lymphatic system are to: Maintain a healthy fluid balance by draining excess fluid from the tissues Filter bacteria, harmful microorganisms, and toxins Remove waste

3 The Lymphatic System The lymphatic system is an extensive system of vessels and nodes that play a crucial role in maintaining fluid balance and cellular health within the body. In addition, it also plays a role in fighting infection and is the primary defense against disease and the negative effects of injury. The main functions of the lymphatic system are to: Maintain a healthy fluid balance by draining excess fluid from the tissues Filter bacteria, harmful microorganisms, and toxins Remove waste including damaged, dead, or cancerous cells Provide a defense mechanism against invading microorganisms through the production of lymphocytes Lymphatic Circulation In order to carry out filtration, the lymphatic system must provide a means of circulation within the body. Unlike the cardiovascular system, which has a central pump (the heart) to aid in the movement of fluid (blood), the lymphatic system does not. The circulation of the lymphatic system relies on movement from the horse. What is exactly circulating in this system? Lymph fluid, a watery, colorless intercellular (within the cell) fluid that is derived from plasma. Plasma seeps from the capillaries to bathe the cells with oxygen and nutrients. Once it has given up its oxygen it drains into the lymphatic capillaries as lymph. Lymph then circulates through body tissues picking up waste, such as bacteria. Lymphatic capillaries turn into lymphatic vessels, a oneway system of channels that run parallel to the venous system. These vessels maintain fluid balance and cellular health by collecting and returning lymph fluid to the venous system of the blood once it is filtered.

Lymphatic Filtration Once the lymph fluid enters a lymphatic vessel, it will encounter a lymph node for filtration.

If there are any foreign/invasive organisms, an immune response will be triggered; this is why when you are ill your lymph nodes will swell!

Lymph nodes are found all throughout the body horses have about 8,000 lymph nodes while humans have up to 700!

4 Lymphatic Filtration Once the lymph fluid enters a lymphatic vessel, it will encounter a lymph node for filtration. Lymph nodes analyze waste material and look for potential pathogens. If there are any foreign/invasive organisms, an immune response will be triggered; this is why when you are ill your lymph nodes will swell! Lymph nodes also house lymphocytes, a type of white blood cell that assists in an immune response; this makes the lymph nodes an essential component of the immune system. Lymph nodes are found all throughout the body horses have about 8,000 lymph nodes while humans have up to 700! A swollen lymph node on a horse indicates an infection of an area that those lymph nodes drain. On the horse, the easiest lymph node to palpate (feel) is under the mandible (submandibular lymph nodes). A common infectious and highly contagious disease that results in the swelling and sometimes rupturing of submandibular lymph nodes is Strangles. Once lymph fluid has been clean and filtered, it re-enters the blood supply.

Lymphatic Flow Lymph fluid empties into a series of lymphatic vessels Lymphatic vessel meets up with lymph node Lymph node filters lymph fluid No Pathogen(s) Finds Pathogen(s) Lymph fluid re-enters

5 Lymphatic Flow Lymph fluid empties into a series of lymphatic vessels Lymphatic vessel meets up with lymph node Lymph node filters lymph fluid No Pathogen(s) Finds Pathogen(s) Lymph fluid re-enters blood supply Cleans & filters lymph fluid Activates immune response Other Lymphatic Tissues In addition to the lymph glands, the spleen and thymus are two other lymphatic tissues that aid in producing lymphocytes and fighting disease. The spleen is the largest mass of lymphatic tissue in the horse s body. Its main function is to produce lymphocytes to fight infection and eject stored red blood cells to enhance aerobic capacity. The thymus, an endocrine gland, also produces lymphocytes. The spleen (bluish hued structure pictured) stores roughly 1/3 of the red blood cells. During exercise, these blood cells are released to increase blood volume, thus increasing the amount of available oxygen increasing stamina and endurance

Management of the Lymphatic System Since the lymphatic system relies on movement to circulate lymph fluid, lack of movement can result in excess tissue swelling.

This management practice, while not often fixable in a training center or racetrack environment, goes against the mechanics of the lymphatic system.

6 Management of the Lymphatic System Since the lymphatic system relies on movement to circulate lymph fluid, lack of movement can result in excess tissue swelling. Let s consider modern equine management, especially at a racetrack what do racehorses tend to do most of their day? Stand in a stall! This management practice, while not often fixable in a training center or racetrack environment, goes against the mechanics of the lymphatic system. Appropriate management strategies, such as walking horses in the afternoon, allowing horses to go out and graze, or even getting a few hours of turnout, can help overcome this issue. Lack of movement can predispose a horse to have lymph fluid accumulate, especially distally in the limbs. This ailment is known as Stocking Up. Horses that stock up have cold swelling of the lower limbs, which is a result of decreased activity. This typically happens after a normal day of training followed by being stall-bound. Getting the horse moving via turnout, hand walking, or even riding will help alleviate the swelling. Some trainers may choose to place standing bandages on horses after training if they tend to stock up; bandaging the leg will create warmth and increase circulation, which will help minimize lymph fluid accumulation. Stocking up does not tend to pose any issues unless it continues on for multiple days. Excessive swelling can create skin folds, which retain moisture and dirt. Eventually, heat will build up in the folds, causing inflammation, skin cracking, and possible infection. If you have a horse that is showing heat in addition to swelling he is not stocked up! This is a red flag that the horse has an active inflammatory process. While it could be a minor issue, such as a small scrape, it could also be indicative of a much larger problem, especially if lameness accompanies it.

The Urinary System The urinary system plays an important role in homeostasis, which refers to internal balance or equilibrium, and

The urinary system consists of: Kidneys Ureters Bladder Urethra Kidneys The kidneys are an organ of detoxification responsible for

Located beneath the ribs near the end of the thoracic and beginning of lumbar vertebrae, the horse s two kidneys sit slightly

Filtration Each kidney is covered by dense fibrous tissue known as a kidney capsule.

The filtration mechanism of the kidney is found in its renal cortex this area of the kidney consists of millions of nephrons,

7 The Urinary System The urinary system plays an important role in homeostasis, which refers to internal balance or equilibrium, and is responsible for filtering the blood and eliminating waste from the body. The urinary system consists of: Kidneys Ureters Bladder Urethra Kidneys The kidneys are an organ of detoxification responsible for cleaning the blood, removing toxins, and excreting liquid waste as urine. Located beneath the ribs near the end of the thoracic and beginning of lumbar vertebrae, the horse s two kidneys sit slightly behind where the back of the saddle covers. The right kidney is a bean shape while the left kidney is actually heart shaped. Filtration Each kidney is covered by dense fibrous tissue known as a kidney capsule. This capsule, as well as surrounding organs, fat, and vertebrae, help protect the kidneys from trauma. The filtration mechanism of the kidney is found in its renal cortex this area of the kidney consists of millions of nephrons, which are responsible for filtering blood. Blood is brought from the aorta to the kidney by the renal artery. Plasma, containing water, platelets, glucose, urea, hormones, enzymes, vitamins, and minerals are all forced into the nephrons. The red blood cells are too large to be filtered out, so they remain in the renal capillaries.

During filtration, the nephrons filter out salt and reabsorb water to maintain a correct water balance in the body. 99% of water is reabsorbed, with only 1% being excreted in urine.

The renal pelvis becomes the ureter, a tube that takes the newly formed urine to the bladder. Effect on Exercise The kidneys play a vital role during your horse s training.

sweating. In order for the kidneys to do this, a horse must be hydrated! Adequate water intake is necessary to keep the kidneys working and filtering.

8 During filtration, the nephrons filter out salt and reabsorb water to maintain a correct water balance in the body. 99% of water is reabsorbed, with only 1% being excreted in urine. The entire blood volume of the horse (about 12 gallons) passes through the kidneys more than 60 times in 24 hours! The liquid waste (urine) then trickles into the renal pelvis. The renal pelvis becomes the ureter, a tube that takes the newly formed urine to the bladder. Effect on Exercise The kidneys play a vital role during your horse s training. When a horse is exercising, the kidneys will reabsorb more water to help keep blood pressure high; this will deliver more oxygen and energy to muscle cells and replace the fluid that is lost from sweating. In order for the kidneys to do this, a horse must be hydrated! Adequate water intake is necessary to keep the kidneys working and filtering. If there is too much water, the kidneys will filter it from the blood and simply produce more waste, i.e. urine. If there is not enough water, the kidneys will conserve a great deal more during the filtration process and produce more concentrated urine. Bladder The bladder is responsible for storing urine. With an enormous capacity to stretch, it is able to store about 4.5 liters of waste (1.189 gallons). Depending on water intake, climate, activity, etc. he will produce anywhere from 1 4 gallons of urine per day. Keep in mind that this is not the only way water is excreted sweating, breathing, and feces all involve water loss. Once a horse s bladder is full, sensory receptors tell the CNS, which tell motor neurons to contract the bladder and allow urine to exit. Urine leaves the bladder via the urethra. In male horses, the urethra is located in the penis while in female horses with is through an external opening within the vulva. Male Horse

Horses on high protein diets and/or those that produce a lot of urine will excrete more urea, which can be bothersome to both horse and human.

9 Management of the Urinary System One of the components of urine is urea, a breakdown product of protein. When urea is excreted it converts to ammonia, a pungent and foul smelling odor that is extremely irritating to mucous membranes lining the mouth, eyes, and respiratory tract. Horses on high protein diets and/or those that produce a lot of urine will excrete more urea, which can be bothersome to both horse and human. Even if your horse is not on a high protein diet, urea will still be a component of urine, so management techniques that reduce its caustic presence will be key. Here are a few strategies that can help minimize the effects of urea, and therefore, ammonia: Clean stalls thoroughly each day Lay down a stall freshener, such as PDZ o These products will capture, neutralize, and eliminate harmful levels of ammonia Avoid cleaning stalls with a horse present Provide good ventilation to help improve airflow

10 Self-Knowledge Checks 1. The circulation of the lymphatic system relies on: a. Kidneys b. Systemic circulation c. Movement d. Respiration 2. Once lymph fluid has been filtered it returns to the: a. Arterial system of the blood b. Venous system of the blood 3. Which lymphatic structure is responsible for analyzing lymph fluid? a. Lymphatic capillary b. Spleen c. Kidneys d. Lymph node 4. An increase in lymphocyte production may indicate: a. A present infection b. Irregular circulation c. A neurological deficit d. Nothing 7. Liquid waste that is produced by the is transported to the bladder by the. a. Urethra / Kidney b. Bladder / Ureter c. Ureter /. Urethra d. Kidney / Ureter 8. Which of the following situations would indicate a horse has drank more water than needed by the body? a. Producing small amounts urine b. Producing large amounts of urine 9. Urine leaves the bladder via the: a. Ureter b. Urethra c. Teat d. Urine vessel 10. Why is ammonia inhalation a cause of concern for the horse? 5. A horse that has cold swelling of the lower limbs may be suffering from what ailment? 6. Which structure is not associated with the urinary system? a. Kidneys b. Bladder c. Thymus d. Ureters e. Urethra

11 Answers 1. The circulation of the lymphatic system relies on: c. Movement The lymphatic system does not have a central pump that circulates lymph fluid movement from the horse is how circulation of lymph fluid occurs 6. Which structure is not associated with the urinary system? c. Thymus The thymus is associated with the endocrine and lymphatic system 2. Once lymph fluid has been filtered it returns to the: b. Venous system of the blood Lymphatic vessels run parallel to the venous system once lymph fluid is filtered, it returns to the venous system 3. Which lymphatic structure is responsible for analyzing lymph fluid? d. Lymph node Lymph nodes analyze waste material and look for foreign pathogens. If one is encountered, an immune response will be triggered 4. An increase in lymphocyte production may indicate: a. A present infection Lymphocytes are a type of white blood cell that assists in immune response 5. A horse that has cold swelling of the lower limbs may be suffering from what ailment? Stocking Up Stocking up is characterized by cold swelling of the lower limbs. This typically occurs after a normal day of training followed by being stall-bound. The cold swelling is an accumulation of lymph fluid movement is often the best remedy 7. Liquid waste that is produced by the is transported to the bladder by the. d. Kidney / Ureter Kidneys filter the blood, remove toxins, and excrete liquid waste as urine. Urine is then transported to the bladder, the storage unit 8. Which of the following situations would indicate a horse has drank more water than needed by the body? b. Producing large amounts of urine The kidneys are responsible for reabsorbing and excreting water as necessary if a horse has taken in too much water, the kidneys will respond by producing more urine to excrete it 9. Urine leaves the bladder via the: b. Urethra 10. Why is ammonia inhalation a cause of concern for the horse? Urea, a component of urea, is converted to ammonia when excreted. Ammonia is a pungent and foul smelling odor that can be extremely irritating to mucous membranes lining the mouth, eyes, and respiratory tract. It also can cause inflammation and constriction of the airways, increase mucus accumulation, decrease stamina, cause coughing during exercise, and cause difficult breathing

12 Glossary Ammonia A pungent and foul smelling odor that is extremely irritating to mucous membranes lining the mouth, eyes, and respiratory tract Bladder Responsible for storing urine, has an enormous capacity to stretch Homeostasis Refers to internal balance or equilibrium Kidneys An organ of detoxification, responsible for cleaning the blood, removing toxins, and excreting liquid waste as urine Lameness A deviation from the horse s normal movement Lymph Fluid Derived from plasma, a watery, colorless intercellular fluid that circulates through body tissues picking up waste Lymph Node Lymphatic tissue that is responsible for analyzing lymph fluid and its waste material, triggers an immune response if a foreign/invasive pathogen is encountered Lymphatic Vessel One-way system of channels that run parallel to the venous system, maintains fluid balance and cellular health by collecting and returning lymph fluid to the venous system once filtered Lymphocytes A type of white blood cell that assists in immune response Nephrons Responsible for filtering blood in the kidneys Plasma The liquid component of blood that suspends other blood components Renal Cortex The area of the kidneys which house nephrons, the main filtration unit Spleen Largest mass of lymphatic tissue, produces lymphocytes and ejects stored red blood cells to enhance aerobic capacity Strangles A highly contagious bacterial infection, a key sign/symptom of strangles is swelling and rupturing of the submandibular lymph nodes Stocking Up An ailment that refers to cold swelling distally on the limbs as a result of decreased activity Thymus An endocrine gland that helps with immunity, produces lymphocytes Urea A component of urine and a breakdown product of protein, converts into ammonia when excreted Ureter Tube that takes newly formed urine from the kidneys to the bladder Urethra Exit pathway for urine, sex of the horse will determine its location (males in the penis, female in an external opening within the vulva)

Structures of the Excretory System include: ü Skin ü Lung ü Liver ü Kidneys ü Ureter ü Urinary Bladder ü Urethra

Excretory System Structures of the Excretory System include: ü Skin ü Lung ü Liver ü Kidneys ü Ureter ü Urinary Bladder ü Urethra Function of the Excretory System The function of the excretory system is