Four items cover a Japanese Bobtail: an echocardiogram every 12 months from age 1, a kneecap exam every 6 months with X-rays at 24 months, a monthly weight on 1 scale, and a yearly urine plus glucose check. The short tail is not one of them. The bobtail trait comes from its own mutation, not the Manx one, and the short tail does not itself cause spinal disease, so no spinal X-ray is indicated because of the tail alone. What does need a calendar is the knee, the waistline, and the heart wall.
What the tail does and does not mean
A Japanese Bobtail carries a mutation that shortens the tail, and it is a different mutation from the one that produces tailless Manx cats. The distinction matters clinically: the Manx tailless gene is linked to sacrocaudal dysgenesis, a spinal cord and nerve problem that can affect the hind legs, bladder and bowel. The bobtail mutation has no such association, and a short, kinked or pom-pom tail in this breed is a shape, not a lesion. If a Japanese Bobtail drags a hind leg or leaks urine, the workup is a neurological exam and a knee exam, and the tail is not the first explanation.
The screen: 4 items, 3 intervals
| Item | First at | Repeat | Cost (USD) | Finds |
|---|---|---|---|---|
| Echocardiogram | 12 months | every 12 months | 250 to 500 | wall thickness, LA/Ao |
| Patella exam | 6 months | every 6 months | 0 to 40 | grade 1 to 4 luxation |
| Hind-limb X-ray | 24 months | every 24 months | 120 to 260 | groove depth, bone angle |
| Urine plus glucose | 12 months | every 12 months | 45 to 120 | USG, crystals, diabetes |
An optional DNA panel at 120 to 220 dollars covers the HCM variants sold across breeds. ; a negative panel does not cancel the echo, and a positive one does not diagnose a cat. The X-ray at 24 months decides whether a grade 1 knee is watched or referred.
Knees: the joint with a real calendar
Patellar luxation is graded 1 to 4: grade 1 pops out under hand pressure and springs back, grade 2 luxates on its own and returns, grade 3 sits out most of the time, grade 4 is fixed out. Medial luxation is the common direction and often bilateral, so both knees are graded at every visit and both go on the film. Two views per hind leg, ventrodorsal and lateral, answer what hands cannot: groove depth, femoral angle, tibial rotation. Surgery, a groove deepening with tibial tuberosity transposition, runs 1,200 to 2,800 dollars per knee and is the usual recommendation for grade 2 or 3 with repeated lameness. Grade 1 with no lameness is managed with weight and a 12 month recheck. The load argument is concrete: a 4.5 kg cat that gains 500 g puts 11 percent more mass through each hind leg on every landing.
Weight: 1 number, 1 scale, 1 target
Body condition is scored 1 to 9, and 5 is the target: ribs felt with light pressure, a waist behind the ribs seen from above. Weigh monthly on the same scale and log it like the weight trend chart. Resting energy requirement is roughly 70 times body weight in kg to the power 0.75, which is about 216 kcal for a 4.5 kg cat; a loss plan feeds about 80 percent of that, near 170 kcal, and aims for 1 to 2 percent of body weight per week, which is 45 to 90 g. Slower is safer, because a cat that stops eating for 48 to 72 hours is at risk of hepatic lipidosis. Measure the food in grams, not scoops, and weigh the bowl once a week to check the pour. A gain of 10 percent in 3 months, or a body condition score of 7 or more, moves the cat onto the plan before the knees complain.
Heart and urine: the 12 month loop
Hypertrophic cardiomyopathy (HCM) is screened with an echo, not a stethoscope, on the Maine Coon protocol rhythm: wall under 5 mm is normal, 5 to 5.9 mm is a grey zone with a recheck in 6 months, 6 mm or more meets the usual definition, and LA/Ao above 1.7 means the atrium is dilating. Ask for those numbers in writing, plus any SAM. The urine test is the other half of the loop: a first-morning specific gravity of 1.035 to 1.060 is normal, 1.030 or lower on a repeat means the kidney is losing concentration, and a glucose reading plus fructosamine at 60 to 120 dollars checks the obese cat for diabetes before the water bowl tells you. A cat that drinks and urinates more is 1 urine test from an answer, and that test costs less than the visit it prevents.
4 signals to log weekly
- Jump height: refusing a surface the cat used 4 weeks ago.
- Gait: a skip in 1 hind leg on 3 or more landings.
- Waist: no visible waist from above, or ribs not felt at 5 on the scale.
- Sleep: resting rate counted over 30 seconds, 30 per minute is the ceiling.
The hour-level call table
| Signal | Threshold | Call within | Why |
|---|---|---|---|
| Open-mouth breathing at rest | any | 0 to 1 hour | heart failure |
| Hind legs dragging, pads cold | any | 0 to 2 hours | aortic clot |
| Straining with no urine | any, male or female | 0 to 2 hours | obstruction |
| Sudden non-weight-bearing | 1 leg after a jump | 12 hours | luxation or fracture |
| Sleeping respiratory rate | 30 or more, 3 in a row | 24 hours | echo within 7 days |
| No food | 24 hours in an obese cat | 24 hours | fatty liver after 48 to 72 hours |
| Weight gain | 10 percent in 3 months | 2 weeks | diet plan before joint signs |
| Drinking more | 2 days in a row, bowl refilled twice | 48 hours | urine and glucose test |
Costs, and the order to spend them
A first year with the echo, 2 knee exams and urine runs 400 to 800 dollars; years 2 and 3 add the X-ray and land at 550 to 1,150. Spend in this order: urine and glucose first, cheapest and it changes feeding; then the echo; then the films. The DNA panel comes last, because no result on it changes the 12 month echo. If a heart drug is prescribed it will be a beta-blocker, a calcium-channel blocker or a clot-prevention class, by veterinary prescription only, never started on 1 fast breathing count at home.
5 steps for the next 30 days
- Weigh the cat tonight and write the number on the fridge, then repeat monthly.
- Measure the daily food in grams and cut 20 percent if body condition is 7 of 9.
- Book the 12 month echo and the urine in 1 visit, 295 to 620 dollars.
- Book the 6 month knee check, both legs graded, and ask for the grade in writing.
- Start the 30 second sleep count tonight, twice a week, in the same note.
None of these steps diagnoses a cat. A luxation is graded by hand and film, HCM is measured on ultrasound, and diabetes is confirmed on bloodwork. The tail is not on the list because it does not need to be: the parts of this breed that need watching are the knee, the waist and the heart.
Terms mentioned in this article
Frequently asked
Does the short tail mean the spine will have problems?
No. The bobtail trait comes from its own mutation rather than the Manx tailless gene, and a short tail does not itself cause spinal disease, so no spinal X-ray is indicated because of tail length alone. A cat that drags a leg or leaks urine needs a neurological and knee exam, not a tail diagnosis.
How much food should an overweight bobtail get?
Start near 70 times body weight in kg to the power 0.75, then feed about 80 percent of that for loss. For a 4.5 kg cat that is roughly 216 kcal at rest and near 170 kcal on the plan, aiming for 1 to 2 percent of body weight per week, which is 45 to 90 g.
Why is a kneecap exam scheduled every 6 months?
Because luxation is graded 1 to 4 and the grade moves in both directions: a grade 1 at 6 months can read as grade 3 at 2 years, and the decision to refer for surgery depends on grade plus lameness episodes rather than on one exam.