The Megacolon-Syndrome is a hereditary disease of homozygous spotted rabbits (En En).
Investigations have been performed on some special traits related to functional aspects of the gut in comparison to vital heterozygous spotted rabbits (En en). It was found that En En rabbits showed significantly reduced sodium absorption rates across the wall of the cecum. Consequently, the dry matter content of the ingesta was reduced at this location, whereas the content of the ashes was increased. These results indicate that a further important pathogenetic aspect of this hereditary disease is an undue liquification of ingesta in proximal parts of the large intestine. （後略）
Hello, I am Zippy a small tricolor Charlie rabbit, over 2 years old. I was born with a congenital disorder that affects roughly 25% of all spotted and checkered rabbits with a butterfly surrounding the nasal region: megacolon.
We, Charlie’s, are bicolored or tricolored spotted straight eared or lop rabbits, characterized by fur is more white over our body than our litter brothers and sisters. Our nasal butterfly is reduced and stops in the middle of our upper lip already, which led to the surname “Charlie”, a reminder of the moustache of Charlie Chaplin.
Our eyes are surrounded by a ring of colored fur, our nasal region has typically a partial butterfly or spots, our ears are usually colored, a colored spot is found on our cheek and we have a finer and/or partial dorsal line. Spots on the hip region are reduced or absent.
The spotted fur is under control of the ‘En’ gene, which is dominant on the ‘en’ gene, responsible for colored fur throughout the body. An ‘enen’ individual will have colored fur all over its body, while an ‘Enen’ individual will be spotted/checkered, and an ‘EnEn’ rabbit will be a Charlie with a very white fur. Offspring of two spotted rabbits (e.g., the Swiss Petit Papillon Tricolor rabbit) that each necessarily have the ‘En’ gene, will thus be composed of newborns possessing:
Heterozygous ‘Enen’ offspring with a spotted coat,
Homozygotes ‘enen’ offspring with a harlequin coat,
Homozygotes ‘EnEn’ offspring with the characteristic white fur characteristics and few colored regions only.
Charlie spotted rabbits suffer from the megacolon syndrome
The deleterious effects of the ‘En’ gene manifest themselves at several levels in homozygous ‘EnEn’ individuals. Many newborns die at weaning or shortly thereafter. Those that survive often develop chronic megacolon, a syndrome that worsens with age. This condition is caused by an abnormal dilation of the colon and by the absence of neuroganglionic cells (aganglionosis) regulating the muscular contractions of the digestive system, which allow its content to progress towards the anus. The activity of the intestine as well as the cecum is affected.
The small intestine is shorter in megacolon rabbits, compared to normal rabbits. The pH of the intestinal content at the initial portion of the small intestine (duodenum) is also lower than that observed in normal rabbits.
Absorption of sodium (Na+) through the wall of the cecum is much reduced. As a result, this organ has a reduced content of dry matter derived from the ingested food. Abnormal liquefaction of the intestinal content has also been observed in the first half of the colon (proximal colon).
The heart and adrenal glands of megacolon rabbits are larger than those of healthy rabbits. It is possible that the increase in the size of these organs is associated with the metabolic megacolon disorder.
Effects of megacolon on health and fecal production
Abnormalities of the intestine and the cecum result in a distension of the abdomen. Megacolon rabbits often have the appearance of having a pot belly stomach. These changes lead to intestinal food malabsorption and, consequently, nutritional deficiencies. These rabbits must receive a variety of food rich in fiber: good quality pellets containing minerals and vitamins, fresh hay and, if tolerated, a variety of fresh vegetables and aromatic herbs. In some megacolon rabbits, the administration of vitamin C or multi-vitamin supplements has allowed them to gain vitality and produce more normal looking and drier hard droppings.
Fecal production is also affected. The hard droppings are large, oval, and rich in water, like a sponge. It is impossible to detect the presence of fibers when fresh. The latter only appear once the droppings have dried out, which may take a few days.
Mucus is often present, which is indicative of a disorder or irritation in the intestine.
Some anecdotic studies mention that megacolon rabbit may never produce cecal droppings. Zippy did, however, bend down towards his anus several times a day, then took the characteristic position of any rabbit ingesting his “trophy”.
A megacolon crisis is caused by the passage of a particularly large hard dropping and is accompanied by abrupt and violent abdominal spasms. Droppings collected at the end of such a crisis often present an outgrowth. Thir progression through the intestine was accompanied by severe pain. Zippy did often moan, in spite of analgesic medication, and he would knock strongly onto his abdomen with his nose during these episodes.
More and more spotted straight-eared or lopped rabbits become pet rabbits nowadays. It is, therefore, important to understand the causes of intestinal crises and be able to treat them. To date, there is no consensus between veterinarians and experts.
Crises are episodic, characterized by sudden outbreaks and calm periods. Dehydration, lack of fiber, nutrient deficiencies, or stress (unusual noise, abrupt weather changes) may trigger them. During a crisis, Zippy had been administered a painkiller (Metacam) and received 2 ml of virgin olive oil orally. This oil has stimulating properties on the intestinal peristaltic movement. It acts softly, without intestinal cramps (there is a risk of rupture of the caecum during these crises) in contrast to chemical stimulants of the peristaltic movement (e.g. metoclopramide, cisapride). Zippy was kept hydrated orally with a syringe. Hay and fresh or dried greens possessing carminative or antispasmodic properties such as celery branches, coriander, fennel, thyme, lemon balm, or raspberry leaves were given on a daily basis, at will. If he tolerates it, his abdomen is gently massaged and he was encouraged to exercice. The longest crisis up to the age of 2 years lasted 9 hours. Luckily, Zippy came out well every time. The frequency of intestinal crises decreased after Zippy was given sunflower seeds daily.
Zippy died at the young age of 4 years and some weeks after struggling with renal failure during the last weeks of his life.
実は、もともと赤ちゃん用のものなので、infant gas reliefなどの語句で検索すると、これを使用した方が良いのかどうかについて書かれたページにヒットします。
Take into account the fact that rabbits socialize in groups. While most rabbits raised for meat are kept in cages, we require group pens on solid floors with plenty of dry bedding, additional places to hide and climb, and room to forage, groom, hop, socialize and play.
These are the rabbits who will be bred over and over (Oz Farms, one of the growers who will be supplying Whole Foods in Northern California, brags that “one rabbit can produce up to 320 pounds of meat in a year in just a small area” – Press Democrat, June 20, 2014) until they are spent, while their babies (called “fryers”) are slaughtered, with no protection from the Humane Methods of Slaughter Act, screaming in pain.
(There are two preferred methods of killing rabbits before their throats are slit–one involves smashing them on the head with a blunt object like an iron bar, and the second involves pulling on their body while snapping their head back, breaking their neck. Neither are foolproof, nor are they painless. They are slaughtered at 9-12 weeks, when they reach 5 pounds, or 2.5 pounds “dressed,” which means butchered.) Oz makes $7.99 for each of the rabbits that they raise, kill and sell (Press Democrat, Jan. 2, 2014).
On Monday 6/30, Rufus suddenly stopped to eat. Here is the record of his conditions.
Give critical care 60ml + meloxicam 0.5ml (1.5mg/ml) oral
Give massage. Slow gut sound is observed. He dug carpet several times (This is normal action he does when he feel pain and try to recover from GI stasis), but quit soon.
No feces and urine observed through the day.
Rufus’s small intestine still responds my massage (more correctly, oriental “Chi” treatment which encourages intestine’s movement more active).
Usually he get well with the treatment in 2~3 hours if GI stasis is mild.
His condition doesn’t improve.
Because Rufus’s gut sound stopped and doesn’t respond my “Chi” anymore, I take him to UW-Vet.
Doctor give his dignosis of GI stasis. Rufus get 150ml fluid.
Somehow, he doesn’t show any sign of dehydration. His back skin and gum is still soft.
His condition looks typical mild GI stasis, so I agree to try fluid and get him back to home.
At home, give 20ml critical care + meloxicam 0.4ml oral + metoclopramide 0.5ml (1mg/1ml) oral.
Rufus’s fluid under his skin is mostly absorbed. No urine is observed.
He doesn’t show any sign of recovery. Stomach start to swell.
G. Flentke (a former WHRS chapter manager) mentioned about a possibility: Rufus is severely dehydrated and the 150ml fluid is not enough, though his skin doesn’t show any sign of dehydration.
I feel like it’s not a problem of intestine, but he has issues somewhere in stomach and the duodenum. Usually in Rufus’s case, small intestine and cecum stops first, feel low temperature around lower abdominal. However, this time I feel issues on stomach and somehow staff inside the stomach doesn’t get through the duodenum. I start to doubt ileus.
Take Rufus to UW-vet again. We agree that his condition is getting worse, now his stomach is full of gas, and need X-ray to proceed next step.
In the next one hour, Rufus’s stomach get harder and harder
Got X-ray image. no ileus is found!
During Rufus is under sedation, Dr. Sladky tried to release gas in stomach with tube, but does not succeed.
Make discussion with Dr. Sladky how we treat him. I feel dangerous to let him go home because his stomach is very hard, so Rufus stays in hospital care. He get fluid with IV catheter.
7/1 6:00 Rufus start to move around, show interest to foods
I see him at UW-Vet. He looks much better than last night.
Massive amount of gas in stomach moved to intestine. Cecum is still gassy.
He ate carrots and small amount of hay, and droped hard feces and cecum pellets.
He looks better so I take him back to home.
He eat small amount of hay and carrots. I hear clear gut sound.
He drops hard feces.
photos and movies
7/1 22:30 give 20ml critical care.
His interest to food is gradually decreasing.
I still hear his gut sound, now his stomach and intestine responses my “Chi” quickly.
I feel remaining gas in his stomach, intestine and cecum, but his abdomen have more strength than yesterday. I’m not sure why he is loosing interest to food, and looks uncomfortable.
Because his stomach is not full, give 10ml critical care to let move his intestine.
He looks tired (or uncomfortable).
Give another 10ml critical care and 0.4ml meloxicam.
Dr. Sladky’s prescription is 0.9ml for every 24 hours, but I split the doze in two.
All my bunnies tend to run out the pain relief effect in the last ~5 hours and stop eating, then they feel uncomfortable again after 6 hours. It may be because I’m using “chi” treatment too, it helps to move GI track, but the same time it tend to enhance liver function that may result in excretion of the drug earlier than prescribed.
7/2 16:00 He finished 1 inch length of carrot. I’m not sure if he ate hay or not because I was on work.
With Chi treatment he start to nibble small amount of hay.
Give 20ml critical care + 0.5ml meloxicam, but he hated to be wrapped.
Total amount of feces and urine in the last 24 hours:
I don’t hear gassy sound from his intestine anymore, but still he doesn’t recover his full appetite.
Usually the amount of hay he nibbles increases gradually, but I don’t see the sign yet.
He is very picky about hay.
Good news is he eats carrot tops, romaine lettuce, broccori, and small amount of water-soaked normal timothy pellets (~1 tsp).
He shook his head when he eat soaked pellets, it looks like he is trying to avoid to touch left cheek (or gum) with food. I hear strange sound when he is grinding. He also doesn’t eat hard part of vegetables.
Might be a teeth issue?
Size of hard feces is getting smaller than last night.
7/3 0:00 Give 20ml critical care + extra 0.5 ml meloxicam.
He resisted hardly (he ate most of them though).
I start to doubt mouth issue, because Rufus is a very sensitive boy about it.
May be that was the direct cause why he stopped to eat suddenly.
I hear normal sound from his guts and his abdominal strength recovered almost normal.
He may be uncomfortable, but for me it doesn’t seem to be a cause why he still hesitate to eat, there will be another cause (most likely mouth issue).
In the past experience about Rufus, I learned pain medication will help to improve the situation, so I gave extra 0.5 ml meloxicam.
7/3 0:30 Rufus start to hop around, and eat hay. After a while, he start to nibble small amount of vegetables and soaked pellets without my “Chi” treatment.
7/3 4:00 Rufus nibbled thick stem of hay, which he was avoiding in the past 3 days.
He also finished soaked pellets (in total 1 tbs). 7/3 9:00
I give soaked pellet (1tbs), and he finished 1/3. Also, he eat small amount of romaine lettuce.
Because he hate to be wrapped and eat critical care, I stop syringe feeding.
Give 0.3ml meloxicam (1/3 of 24 hours doze).
During the night he tried to eat some vegetables. He is still trying to avoid hard part.
However, it’s good that he start to eat by himself — without my attention.
feces from 16:00 yesterday:
the size and amount of feces is smaller than yesterday. He passed urine on two other litter boxes.
7/3 12:00 Rufus start to dig carpet, and then eat vegetables. He also finished almost all amount of soaked pellets.
I think he is on recovery track and I don’t hear strange grinding sound now, but I’m a little worrying about this long weekend… If he has a teeth issue, he may get worse again during the weekend.
However, I’m not sure what doctors can do for his teeth right now, because I guess it is very minor issue. May be I should have subcutaneous fluid in my home just in case if he get dehydrated again??
7/3 20:00 Got fluid kit from UW.
He eats soaked pellets and vegetables.
feces from yesterday
He finished remaining pellets. Give meloxicam 0.3ml.
He eats a lot of vegetables.
He also start to eat enough amount of hay, finally he is recovered?
(but still picky, he can eat oats hay and soft timothy leaves only)
He finished vegetables, but it looks like he didn’t eat in the last 4 hours.
His GI track is getting slower again.
Give soaked pellets(1TBS). Rufus finished 2/3 of it.
Give meloxicam 0.3ml.
7/4 12:00 He is losing interest to food again. Looks uncomfortable.
Guts sound become slower.
feces from last night
Since he doesn’t drink water at all, give electrolyte solution + critical care (just a pinch) with syringe. I hear large growling from stomach. I understand he was dehydrated again.Give meloxicam 0.3ml.
He looks very uncomfortable.
7/4 20:00 He eats soaked pellets a little, but looks uncomfortable, and I don’t see his GI movement. Also I feel gas bubbles in his intestine.
7/4 22:00 Rufus drinks orange mango juice 40ml (diluted with electrolyte solution 60ml), he finished all in one hour. I added another juice 30ml diluted with electrolyte solution 60ml. He drinks 1/3.
He start to eat hay, but still picky. He eats oats hay and
I still doubt teeth problem.
I give meloxicam 0.3ml.
He eats hay well up to 3:00, but it looks like he stopped to eat after I went to bed. Somehow he lose interest to food when I’m not in living…
But he finished 1tbs soaked pellet.Because I feel gas in stomach, I give 0.3ml meloxicam and 0.3ml infant gas reliever.
Size of feces is getting larger.
7/5 16:00 He doesn’t eat at all in the last five hours, and looks uncomfortable. His guts sound gets slower again. He seems to become worse in daytime.
I don’t want to disturb his sleep, but if I don’t let him eat at all, his GI gets full of gas at night as yesterday…
I give very thin critical care and 0.3ml meloxicam.
7/5 22:00 He finished water soaked pellets (1tbs).
He start to recover his appetite around 20:00, but he can’t eat hay (he shows interest but doesn’t eat).
I give hay cube and somehow he start to eat!I have no idea why a bunny can eat cubed hay but not loose hay??
7/6 0:00 Because he doesn’t drink water for 24 hours, I give electrolyte solution + critical care with syringe. give 0.3ml meloxicam
He is eating some hay, but not as much as yesterday.
Is he having teeth problem? or having Retrobulbar Abscess again so that his molar doesn’t meet in right position?
7/6 6:00 He doesn’t eat in the last 4 hours (during I was sleeping…)
give massage 20 min, and he start to eat vegetable and drink a little amount of juice.
7/6 9:30 He finish 1tbs water soaked pellets. looks better than yesterday, but I think it’s because he drink juice at 6:00 am.
Give 0.3ml meloxicam.
He dropped a lot of feces last night though.
His stomach and intestine getting larger again, and I hear gas sound…
give very thin critical car (almost water)
give very thin critical car (almost water), meloxicam 0.3ml
After one hour, he start to nibble hay just small amount.
He is eating hay. It looks like he is using only right molar to eat long hay?
Turn on air conditioner. He start to eat loose local hay.
7/6 20:30Give 1TBS soaked pellets. He finished all.
He eats feces(I’m not sure if this is cecal pellet or not). He is eating it very frequently today.
eats vegetables (parsley, celery, romaine lettuce) and hay.
Looks quite normal appetite. If he drinks pure water, I feel much better…
Drinks mango-orange juice + water, nibble hay cube.
Because he is still eating, I skipped meloxicam.
His condition will be monitored every three hours.
Rufus is eating hay and drinking orange juice + water.
However, he is trying to avoid to use left molar…
He still nibbles a small amount of hay.
He finishes 1TBS soaked pellet quickly. After that, I hear gas sound from his intestine and he looks uncomfortable.