Liver Anatomy

 

Photo by Dr. Haus

Liver Anatomy

The anatomy of the liver must be understood to truly understand the functioning of this vital organ.  Of course this is required for all organs but, as usual, I digress...  

🪅

The liver sits in the upper-abdominal region of most mammalian organisms situated beneath the diaphragm.  The diaphragm is the muscle that separates the thoracic (chest) cavity from the abdominal (belly) cavity as well as assisting an organism with breathing.  

❓

Thought provoking question (based on the above paragraph) - what might happen in a patient whose liver is severely enlarged?  I saw this in my clinical rotations and this patient stumped the docs for a brief time as this clinical sign/symptom is not immediately thought of as being caused from liver enlargement. 

🐳

Check out the image of the liver, gallbladder, stomach, spleen, pancreas, and small intestines of a human with its associated blood vessels/biliary ducts:

   

Photo from: https://www.hopkinsmedicine.org/-/media/images/health/1_-conditions/liver-gallbladder-and-pancreas/liver-anatomy.png 

 

Liver Lobes

Liver lobes are macroscopic (visible with the naked eye) sections of the liver that can be seen when looking at a liver.  The number and names of the liver lobes is dependent on species.  Some examples are below:

Dogs - 6 lobes

Cats- 6 lobes

Horses - 5 lobes

Cattle - 4 lobes

Whales - 2 lobes

Pigs - 5 lobes

Humans - 4 lobes

Image of a Pig Liver with 5 Liver Lobes:

 

Photo from:  https://www.researchgate.net/figure/Anatomic-features-of-pig-liver-a-Pig-liver-showing-relative-position-of-each-of-the_fig4_23803968

 

Liver Lobules

The liver is often discussed in microscopic (cannot be seen with the naked eye) terms as liver lobules.  A liver lobule is a small grouping of liver tissues that make up the functional unit of the liver.  A functional unit of an organ is the smallest categorization of an organ that can perform all of the organ's function.  The liver lobule is the smallest categorization of the liver that can perform every basic function the liver needs to keep an organism healthy. 

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There are three (3) major parts of a liver lobule: 

 

1. Portal Triad (five (5) parts)

    1. Proper hepatic artery (portal arteriole) - Supplies oxygen to the liver, this vessel is an arteriole off the hepatic artery

    2. Hepatic portal vein (portal venule) - High in nutrients and low in oxygen, this vessel is a venule off the portal vein

    3. Bile ductules (bile duct) - Branches of the biliary system, these ducts move bile through the liver

    4. Lymphatic vessels - Vessels which move lymph through the liver (not pictured in image below)

    5. Branch of the vagus nerve - Nerve innervation from the vagus nerve, autonomic nervous system (not pictured in image below)

2. Central vein - Venule that drains deoxygenated hepatic blood into the hepatic vein

3. Hepatocytes - Liver cells

 

Photo from:  https://upload.wikimedia.org/wikipedia/commons/b/b7/2423_Microscopic_Anatomy_of_Liver.jpg

 

Portal Vein Anatomy

The portal vein is arguably the most important vessel to understand within the liver because it collects all of the blood that comes from the gastrointestinal system (large intestines, small intestines, stomach, etc.), gallbladder, pancreas, and spleen.  Now, think about what the previous statement means - what does the portal vein carry?

🍛

You guessed it - the portal vein carries EVERYTHING the gastrointestinal tract absorbs and brings it to the liver.  This means the portal vein carries a HUGE amount of nutrients from food, water, microorganisms, toxins, bile salts, etc.  The large amount of microscopic materials present in the portal vein explains the major functions of the liver due to its need to process all of the different contents of the portal vein upon its arrival to the liver.  

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*In a normal, healthy organism, the portal vein will arrive to the liver and the blood will be processed by the liver PRIOR TO returning to the right side of the heart.* (thought provoking question - why is this important?)

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Below is an image that illustrates how all the blood from the gastrointestinal tract flows into the portal vein.  This blood then arrives to and is processed by the liver prior to returning to the heart.

 

 

Photo from:  https://projects.cos.ncsu.edu/bio370/wrap/TopicsFolder/circulatory3/text_images/portal_vein.jpg 

 

Now that we understand the basic anatomy of the liver, we will continue to explore the different functions of the liver to allow us to work through some upcoming liver-related cases.  Keep up the great work and catch you all in the next post (which will hopefully happen in a quicker time frame)!

 

The Liver

 

Photo by Dr. Haus

The Liver

The liver is an organ that always fascinated me but was never a large focus in any of the courses I taught as there was never enough time.  This bothered me as as the liver affects every other organ in the body and affects the ability of an organism to function and survive.  The liver is an often neglected organ in the study of body systems, especially for undergraduate students.  The liver only took up about one-third of a lecture in my Pathophysiology course though it was not nearly enough time to dive into the amazing world of the liver.  I always dreamed of offering a course that was entirely based on the liver and this is what I am going to try to do here in this blog through this post and many more.

🤓

Liver = Love

A previous student once spoke to me after the liver lecture and mentioned that in their culture the liver is the organ representing love.  They explained to me that you tell someone they are your liver as the strongest way to express your love for another person.  This fascinated me as it was new information and I have an odd interest in the history of language, the root of different words, and understanding other cultures.  As I have read more and more, I see that the liver is used in numerous languages and phrases from African nations to Middle Eastern nations to Eastern nations to express unconditional love and emotion.  

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From a completely scientific standpoint, it makes sense that the liver is associated with love in many cultures as the liver is a vital organ in the body that processes all of the blood flowing throughout the body.  After diving into this information more deeply, I learned most Eastern and Middle Eastern cultures view the liver as the organ of love, not the heart like the Western world.  In the spirit of creating a liver-focused post, I knew I needed to do some digging into the history of the liver in different cultures, and its focus on symbolizing love.

😻

Liver Etymology

Etymology is the study of words, their history, and how words change over time.  This is a great starting point for the word liver because historically it was considered the organ of love, life, emotions, pleasure, and passion.  In Western languages, the liver's historical origins are that it is the organ of emotions, the organ of life, and the organ of courage.  It is interesting that even during ancient times the recognition of the liver's importance for survival was well understood.  To learn more about the etymology of the liver check out the sources links below [1].

🫰

Digging deeper into the history of the liver further increases my fascination with this organ as multiple different ancient cultures viewed the liver as central to the functioning of humans.  Hepatocentrism was the focus of medicine in most ancient populations of humans.  The ancient civilizations in Mesopotamia considered the liver central in the functioning of a human body and the Western world did not move away from this mindset until the 1600s.  The liver was thought to be where a human's soul was housed with some even believing there was a fire (soul) burning in each person's liver [2].

❤️‍🔥

Ancient religious texts, pieces of famous literary works, Greek mythology, and medical writings all focus on the liver being the center of human life in ancient times.  Some of the famous works that demonstrate the reverence felt for the liver are listed below [2]:

• The Quran
• Moby Dick
• The myth of Prometheus
  
• The Bible
• The Tale of Hind bint ‘Utbah
  
• Snow White
• The Torah
• The God of death in ancient Aztec mythology
• The myth of Tityus
• The Iliad
• Ancient Chinese, Persian, and Urdu medical texts
• The crucifixion of Jesus Christ
  

🧑‍🎨

It is interesting to note that the ancient Egyptians did NOT see the liver as the location the soul - the ancient Egyptians saw the heart as the location a soul resides.  This is the reason why the heart was left in a mummified corpse while the liver was not.  The heart remaining in the corpse was thought to allow the person to move into the afterlife to live on forever [2].

🇪🇬

In the 1600s, medical knowledge started to change and scientists of that time discovered that many of the functions they associated with the liver were actually associated with the heart.  It was during this time Western culture started moving away from its reverence for the liver.  There is a work of art in the Museo Storico Nazionale dell'Arte Sanitaria in Rome, Italy called "Il Fegato" that depicts the heart and liver fighting over being the king of organs through the production of blood (interestingly enough, the heart does not produce blood as you all know, but I guess talking about the bone marrow isn't as cute as the heart).  Moral of this story?  I need to get to Rome to check out this painting [2]! 

🇮🇹

Above is a very brief outline of the history of the liver and helps explain common phrases related to the liver in many cultures.  What is most interesting is the strong correlation of the liver and love in most non-Western cultures that seems to have been lost to the Western world in the seventeenth century.  I highly encourage you all to check out the two sources below [1 and 2] as they are good reads and can jump start you on the fun nerd journey of entomology and the intersection of science, medicine, the arts, and language.  To end, I must say, I love my two little livers (my cats).

😎

Liver Education (To be updated as I complete blog posts)

Anatomy

Liver Lobules

 

Basic Liver Functions

Accessory Organ of Digestion

Organ of Metabolism

Organ of Hematology

Organ of Endocrinology

Organ of Detoxification

Organ of Storage

Organ of Immunity

Organ of Synthesis

 

Liver Dysfunction

Icterus/Jaundice

 

 Sources

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747976/pdf/nihms493154.pdf
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6078213/
   
   
   
   
   
   
   
   
   
   
   

Conclusion Caturday: Vince Vomits Valiantly (Case 7)

Photo of TA Douglas (Left) and Professor Pocky (Right) taken by Dr. Haus

 

Click For Explanation of Case Flow

 

Click for Test Case Tuesday:  Vince Vomits Valiantly

 

Click for Thoughtful Thursday:  Vince Vomits Valiantly

 

Quick Review

Diagnosis:

🦴Myasthenia Gravis🦴

 

Pathophysiological Point:

Myasthenia gravis is a disease where the acetylcholine receptors between nerves and muscles are destroyed or blocked.  Simply, nerves cannot conduct their signals to muscles.  Muscles are unable to contract (move) without the signals from the nerves.

 

 Questions, Answers, and Further Information:

 

Level 1 Questions, Answers, and Further Information:

1. Vince's communication between his nerves and muscles is disrupted, how does that affect the muscles of his body?  Why?
   
   If Vince's nerves cannot communicate with his muscles, his muscles will not be able to move.  The nerves tell the muscles to move and without this signaling he will not be able to contract his muscles easily leading to difficulty moving.
   
   
2. What part of Vince's history and physical exam findings support the diagnosis of a disease that affects communication between the nerves and muscles of his body?
   
   The history and physical exam findings that support his diagnosis are the generalized weakness and muscle loss.  These findings support the fact that Vince's nerves are not able to send their normal signals to the muscles.
   
   
3. Challenge question, why does Vince have megaesophagus?  How does this cause regurgitation after meals?  (HINT:  Think about Vince's disease and how it would affect the muscles of the esophagus)
   
   The esophagus is a muscle much like the other muscles of the body.  In order for food and fluid to get to the stomach, the esophagus must be able to contract.  With Vince's disease, he cannot use his esophageal muscles to push the food/fluid down to his stomach so the food and fluid accumulates in the esophagus causing it to expand and stretch causing megaesophagus.  As this food/fluid builds up in the esophagus it will comes out the mouth because the muscle contractions are not there to get the food and fluid to his stomach efficiently.
   
   

   Helpful Links:

   • VCA (dogs):  https://vcahospitals.com/know-your-pet/megaesophagus
     
     
   • Mayo Clinic (humans):    https://www.mayoclinic.org/diseases-conditions/myasthenia-gravis/symptoms-causes/syc-20352036
     
     
   • Cornell Vet School:  https://www.vet.cornell.edu/departments/riney-canine-health-center/canine-health-information/myasthenia-gravis
     

 

Level 2 Questions, Answers, and Further Information:

1. How does myasthenia gravis cause disease (i.e., megaesophagus) in a patient?  Be sure to mention the “normal” esophageal physiology in your answer and explain physiologically where the miscommunication is occurring.  (HINT:  Review normal neuromuscular junction physiology)
   
   Myasthenia gravis destroys/blocks the acetylcholine receptors on the muscle cells.  Neurons release acetylcholine into the synaptic cleft at the neuromuscular junctions.  This allows the muscle cell to begin to undergo the process of depolarization which will eventually lead to the muscle contracting.  The esophagus is a muscle that must contract to move food/fluid towards the stomach.  With the acetylcholine receptors of the esophageal muscles destroyed/blocked, the esophagus cannot move the food/fluid and the esophagus will expand to accommodate all the stuck food/fluid material.
   
   
2. How does megaesophagus lead to Vince’s major clinical sign (regurgitation)?  (HINT:  Think about what keeps us from floating away into space)
   
   Since Vince cannot contract his esophagus, the food/fluid will sit in the esophagus unable to move aborally.  This leads to the material falling back out the mouth especially when Vince puts his head down as gravity will cause the food/fluid to fall out of the mouth.
   
   
3. Challenge question, explain why Vince has pneumonia.  Be sure to explain how his underlying disease predisposed him to this condition.  Be sure to mention the anatomy involved.  (HINT:  Think about what structure sits right next to the esophagus)  
   
   Vince's pneumonia is likely due to his regurgitation from the megaesophagus.  Each time Vince regurgitates his food, he risks some of the food/fluid accidentally falling into the trachea which sits next to the esophagus.  When food/fluid enters the esophagus there is a risk that the material gets into the deeper lung tissues leading to pneumonia (inflammation of the alveoli).
   
   

   Helpful Links:
   

   • Merck Vet Manual:   https://www.merckvetmanual.com/nervous-system/congenital-and-inherited-anomalies-of-the-nervous-system/neuromuscular-disorders-in-animals 
     
     
   • Cornell Vet School:  https://www.vet.cornell.edu/departments/riney-canine-health-center/canine-health-information/myasthenia-gravis
     
     
   •  Merck Vet Megaesophagus:  https://www.merckvetmanual.com/digestive-system/diseases-of-the-esophagus-in-small-animals/dilatation-of-the-esophagus-in-small-animals
     
     

Level 3 Questions, Answers, and Further Information:

1. Describe the treatment plan you would recommend Vince and why you are recommending each part of your treatment plan.  Please answer this question as if you are speaking to a professional colleague.  .
   
   Vince's treatment plan will depend on the etiology of his disease.  If Vince's disease is due to a thymoma the thymoma needs to be surgically removed.  Otherwise, anti-acetylcholinesterase medications can be used to treat these patients.  Vince will also need to be treated for his pneumonia with antibiotics and other supportive care as needed.
   
   
2. Describe your recommended treatment plan and why you are recommending each part of your treatment plan.  Please answer this question as if you are explaining it to a client/patient without a scientific background.
   
   Vince has a disease that causes his nerves and muscles to not communicate correctly.  We will be starting Vince on a medication that will help his nerves and muscle communicate better while also starting him on antibiotics to treat his pneumonia.
   
   
3. Please describe the different ways Vince's owners could help manage his condition with environmental changes.
   
   There are a few ways Vince's owners can help increase Vince's quality of life at home.  Firstly, Vince should be fed and watered from dishes that are elevated off the floor (less gravitational effects).  The owners can also hold Vince up vertically after meals to help gravity "push" the food/fluid down to his stomach.  His owners should also feed him smaller, more nutrient dense meals to decrease his risk for regurgitation.
   
   

   Helpful Links:

   • Journal of Internal Veterinary Medicine:   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8478050/  
     
     
   • Journal of Clinical Medicine:    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8196750/
   
   

Day 3 Conclusion

I hope you enjoyed the Vince's case!  Don't forget to...

📚 Review material related to the goats' case 

🤩 Get excited for upcoming cases

 

Thoughtful Thursday: Vince Vomits Valiantly (Case 7)

  

Photo of Professor Pocky taken by Dr. Haus

Click For Explanation of Case Flow

 

Click for Test Case Tuesday:  Vince Vomits Valiantly (Case 7)

 Vomiting or Regurgitation?

The MOST important determination to make in a vomiting patient's case is to make sure the patient is actually vomiting.  Vomiting is NOT the same as regurgitation.  Regurgitation is when food/fluid comes out of the mouth from any structure before the stomach (mouth, pharynx (throat), esophagus (food tube), etc.)  Vomiting is when food/fluid come out the mouth from the stomach or upper small intestines.

🤢

This distinction is extremely important because the causes of vomiting and regurgitation are different and the way we work up the two types of cases are completely different.  It is important to remember that an owner can say their pet is vomiting when they are in fact regurgitating food.  The ways you can differentiate vomiting and regurgitation are noted below:

Vomiting

• Abdominal push (abdominal muscles contract to push the vomitus out of the mouth)
  
• Bile present (green substance)
  
• Active process (you can see the whole body put in an effort to vomit)
  

🤮

Regurgitation

• No abdominal push
• No bile present
• Passive process (the mouth opens and the food/fluid comes out, no pushing seen)

 😵

An important aspect of any veterinary professional is to have your acting skills on point as it is common to see us acting out vomiting versus regurgitation.  The things that happen in an exam room are sometimes bananas (ask your vet med friends to act out reverse sneezing, you won't regret it).

 🎭

The owners describe Vince's "vomiting" as him eating his food and then immediately it "falls" back out of his mouth.  The owners do not see Vince actively retching or "pushing" when he has the "vomiting".  It is determined Vince is regurgitating, not vomiting!

 

Diagnostic Testing Results:

 

Radiographs: Severe megaesophagus (enlarged esophagus, food tube), signs of pneumonia 🩻

 

Specific Disease Testing - Acetylcholine Receptor Antibody Test: Positive ➕

 

🧪

Diagnosis:

🦴Myasthenia Gravis🦴

 

Pathophysiological Point:

Myasthenia gravis is a disease where the acetylcholine receptors between nerves and muscles are destroyed or blocked.  Simply, nerves cannot conduct their signals to muscles.  Muscles are unable to contract (move) without the signals from the nerves.

 

 Questions:

Level 1 Questions:

1. Vince's communication between his nerves and muscles is disrupted, how does that affect the muscles of his body?  Why?
   
   
2. What part of Vince's history and physical exam findings support the diagnosis of a disease that affects communication between the nerves and muscles of his body?
   
   
3. Challenge question, why does Vince have megaesophagus?  How does this cause regurgitation after meals?  (HINT:  Think about Vince's disease and how it would affect the muscles of the esophagus)
   

 

Level 2 Questions:

1. How does myasthenia gravis cause disease (i.e., megaesophagus) in a patient?  Be sure to mention the “normal” esophageal physiology in your answer and explain physiologically where the miscommunication is occurring.  (HINT:  Review normal neuromuscular junction physiology)
   
   
2. How does megaesophagus lead to Vince’s major clinical sign (regurgitation)?  (HINT:  Think about what keeps us from floating away into space)
   
   
3. Challenge question, explain why Vince has pneumonia.  Be sure to explain how his underlying disease predisposed him to this condition.  Be sure to mention the anatomy involved.  (HINT:  Think about what structure sits right next to the esophagus) 
   

    
   

Level 3 Questions:

1. Describe the treatment plan you would recommend Vince and why you are recommending each part of your treatment plan.  Please answer this question as if you are speaking to a professional colleague. 
   
   
2. Describe your recommended treatment plan and why you are recommending each part of your treatment plan.  Please answer this question as if you are explaining it to a client/patient without a scientific background.
   
   
3. Please describe the different ways Vince's owners could help manage his condition with environmental changes.
   

  

Day 2 Conclusion

Before Conclusion Caturday think about your...

❓Answers to the above questions

📚 Review Material Related to Vince's case

 

Conclusion Caturday: Vince Vomits Valiantly (link will go live Saturday, 02/17/2024)

 

Test Case Tuesday: Vince Vomits Valiantly (Case 7)

 

Picture of Professor Pocky taken by Dr. Haus

Click For Explanation of Case Flow

 

Signalment:

Vince is a 4-year-old male neutered Labrador Retriever Dog

🐶

History:

Vince is presenting for vomiting his food after every meal, generalized weakness, and lethargy.  His owners note that for the past few meals (even small ones) Vince will vomit immediately after he eats any food.  ​

Vince has a 2-year-old Labrador Retriever female spayed sister named Vanessa.  Vanessa is showing no signs of illness.

🤮

Physical Exam Findings:

Respiratory:  Raspy lung sounds​ 🫁

Musculoskeletal:  Generalized muscle weakness/atrophy (muscle wasting)​ 🏋️

 

🩺

 

🛑STOP and brainstorm what diagnostic tests you would like to perform on Vince 🛑

 

 

We will be stopping here today.  Before Thursday, think about what question(s) you need to ask Vince's owners to fully understand his history (Hint: Think about vomiting).  We will review an important distinction veterinarians need to make with vomiting patients and what diagnostic testing will be done based on that knowledge.

🧪

Day 1 Conclusion

Before Thoughtful Thursday think about your...

📋 Differentials List

🧪 Further Diagnostic Testing

📚 Review Material Related to Vince's case (i.e. what questions to ask owners of a vomiting patient, questions to ask a vomiting patient (if patient is a human that can communicate), specific diseases of interest, causes of vomiting, types of vomiting, personal interests, confusing points, etc.)

 

Thoughtful Thursday: Vince Vomits Valiantly (link will go live Thursday, 02/15/2024)

 

Conclusion Caturday: Janice is Jinxed (Case 6)

Photo of TA Douglas (Left) and Professor Pocky (Right) taken by Dr. Haus

 

Click For Explanation of Case Flow

 

Click for Test Case Tuesday:  Janice is Jinxed

 

Click for Thoughtful Thursday:  Janice is Jinxed 

 

Quick Review

Diagnosis:

🐮Ketosis🐮

 

Pathophysiological Point:

Ketosis is a condition where the body is breaking down fats at an extremely elevated rate due to a negative energy balance.  This energy imbalance occurs because the body is using more energy than it is taking in through eating.

 

 Questions, Answers, and Further Information:

 

Level 1 Questions, Answers, and Further Information:

1. Why do you think Janice is suddenly breaking down more fat?  In other words, why would Janice have a negative energy balance?  (HINT:  Think about Janice's history and physical exam findings)
   
   Janice is in a negative energy balance and breaking down more fat because she recently had her calf and is producing a large amount of milk.  In addition, Janice has a high body condition score (BCS) and thus has more fat in her body than an animal with a normal BCS.  It takes a lot of energy to make milk and Janice needs A LOT more energy to make milk for her baby (lactation).
   
   
2. What is the pathway that is occurring at an increased rate in Janice's body?  Please write out all the steps of the process and include what molecule there will be more of in Janice's bloodstream.  (HINT:  Click here)
   
   The process that is happening at an increased rate in Janice is gluconeogenesis of fats.  In this process, the body is breaking down the adipose tissue (fat tissue) into glycerol and fatty acids.  The glycerol is used to produce glucose for the body while the fatty acids accumulate and are converted to ketones.  Due to this, Janice will have more ketones in her bloodstream (her glucose will be taken out of the bloodstream very quickly to make more milk).
   
   
3. Challenge question, what information in Janice's history AND physical exam findings put her at increased risk for developing ketosis?  Why do those factors increase her risk for ketosis?  What ways could the farmer have reduced Janice's chance for developing ketosis?  (HINT:  Think about the underlying cause of the disease in Janice's case)
   
   Janice was at increased risk to develop ketosis due to her birthing a calf and because she was overweight before having the calf.  Having a calf puts Janice at increased risk for developing ketosis because after having the calf Janice needs to produce a large amount of milk.  This causes most of Janice's energy (glucose) to go to her milk and her body will start to break down fats to provide enough energy to produce milk and to keep herself alive.  Janice being overweight is another factor because since Janice is so overweight her body can/will break down a large amount of fat meaning she will produce a large amount of ketones.  The farmer should make sure their cows are not overweight prior to having their calves to decrease the risk of ketosis.
   
   

   Helpful Links:

   • Penn State Extension:  https://extension.psu.edu/preventing-dairy-cow-ketosis-nutritional-management-during-transition
     
     
   • Dairy NZ:    https://www.dairynz.co.nz/animal/animal-health/ketosis/
     
     
   • The Cattle Site:  https://www.thecattlesite.com/diseaseinfo/194/acetonaemia-ketosis/
     

 

Level 2 Questions, Answers, and Further Information:

1. Explain why Janice has low glucose concentrations and high ketone concentrations in her bloodstream.  Do not forget to name the process that is occurring at an increased rate in Janice's body and the steps of this process.  (HINT:  Click here)
   
   Janice has low glucose concentrations in her bloodstream because her body needs more energy than she is taking in by eating to undergo lactation.  In this case, her body is mobilizing fats through the process of gluconeogenesis.  In this process, her adipose tissue is broken down into fatty acids and glycerol.  That glycerol will be used in gluconeogenesis to produce the glucose Janice's body needs to produce the milk and keep her body functioning.  The fatty acids will accumulate and be processed into ketones.  This leads to the high ketone concentration in her bloodstream.  This process is called gluconeogenesis of fats.
   
   
2. High ketone concentrations in the bloodstream lead to inappetence.  How does this information affect Janice's disease process?  (HINT:  Think about how inappetence is affecting Janice's body and her ability to overcome this disease process)
   
   Janice has high ketones in her bloodstream and since ketones decrease appetite Janice does not feel like eating.  The less Janice eats, the more fats she needs to break down.  In this way, the ketones are causing her ketosis to become worse and worse as her body breaks down fats, makes her more inappetent, and thus makes her body break down even more fats.  Janice is stuck in a loop that is making her get more and more sick.
   
   
3. Challenge question, explain why ketosis is very common in dairy cattle, more common in dairy cattle that birth twins, and more common in dairy cattle that are overweight.  (HINT:  Think about what dairy cattle were bred to do and the underlying cause of this disease)   
   
   Ketosis is common in dairy cattle because they are bred to produce HUGE amounts of milk.  Due to this, a dairy cow's body will keep producing huge amounts of milk even if she is not eating enough food to sustain her body and milk production.  This process is also more common in dairy cattle that have twins because the birthing process of having twins uses much more energy than birthing one calf and more milk will be needed to support both calves.  Lastly, overweight dairy cattle are at an increased risk because they have a large amount of fat that can be broken down after they birth their calf and this will lead to them breaking down a higher amount of fat thus increasing the high ketone concentration in their bloodstream.
   
   

   Helpful Links:
   

   • Merck Vet Manual :     https://www.merckvetmanual.com/metabolic-disorders/ketosis-in-cattle/ketosis-in-cattle
     
     
   • Wisconsin Vet School:   https://heatherwhite.webhosting.cals.wisc.edu/wp-content/uploads/sites/164/2015/01/F-08872-15-Ketosis-Understanding-the-Biology1.pdf
     
     
   •  University of Kentucky:  https://afs.ca.uky.edu/content/treatments-dairy-cows-ketosis
     
     
     

Level 3 Questions, Answers, and Further Information:

1. Describe the treatment plan you would recommend Janice and why you are recommending each part of your treatment plan.  Please answer this question as if you are speaking to a professional colleague.
   
   Janice has ketosis and needs to be treated with intravenous glucose to start the process of getting enough glucose in her bloodstream to "break" the ketosis cycle.  After this first IV dose, Janice should be drenched with oral propylene glycol which will provide her extra glucose until her body adjusts to having enough energy for both mother and calf.
   
   
2. Describe your recommended treatment plan and why you are recommending each part of your treatment plan.  Please answer this question as if you are explaining it to a client/patient without a scientific background.
   
   Janice is suffering from a condition called ketosis.  Since Janice had her calf she has been needing a huge amount of extra energy to produce milk and started breaking down her fats for energy.  Unfortunately, Janice has broken down too much fat and it has caused her to get sick.  We need to give her extra energy/sugars in order to help her body adjust to producing milk and keeping her body healthy.
   
   
3. Please create and describe a ketosis prevention plan for this farm to decrease the incidence of ketosis on this farm (both clinical and subclinical ketosis).  Explain the importance of subclinical ketosis and why it is extremely important to prevent this disease process on dairy cattle farms.
   
   There are a lot of answers to this question and I will list some here.  The biggest factor to decrease the risk of ketosis in your herd is to ensure that you are not overfeeding your cows and to make sure they remain in the correct weight range before giving birth.  Additionally, cattle should be monitored closely for ketosis after they give birth.  Cows that recently calved should all be kept in a pen together (often called the fresh pen) to get examined everyday and to have their blood ketone levels tested on an as needed basis.  It is also important to ensure that you are feeding your cattle appropriate nutrition for each stage of their lifecycle to ensure they are getting the nutrition they need at each stage of their lives.
   
   

   Helpful Links:

   
   
   • Veterinary World:      https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8304442/   
     
     
   • Veterinary Medicine and Science:        https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9857124/
     
   
   

Day 3 Conclusion

I hope you enjoyed the Janice's case!  Don't forget to...

📚 Review material related to the goats' case 

🤩 Get excited for upcoming cases