WARNING - SCIENTIFIC GEEK SPEAK!
This is a very interesting question Jo - and like you I am very curious (even frustrated!) about the (lack of) development and possible prevention/alleviation of urinary issues in piggies. (I will PM you on this over the next few days if I may?)
So here is my information in answer to your immediate question:
All my pigs had/have tap water.
1) When I was a kid, my (4 smooth haired male and female) piggies and I, lived in a very hard water area. (Somerset limestone - Wessex Water) No bladder problems at all (even with the benefit of hindsight!) Classic red dutch male, buff sheltie X dutch male, slate/white dutch x sheltie (female) and agouti/black X (female) (Males not neutered - males passed away before females were acquired!)
2) The last 18 "adult" years of piggie keeping has been in a less hard water area - but nevertheless still classified as hard (Sussex clay - South East Water area)
So over the last 18 years, I have been a slave to 3 "groups" of piggies whilst in Sussex.
Group 1 - 4 pigs all deceased: two pet shop females (sisters?) both pregnant with one offspring each. Mummy (Piglet) - smooth/sheltie cross with black dutch markings may (in hindsight) have had a stone. Her daughter Honey (smooth/sheltie cross with buff dutch markings) had no urinary issues. The other mum (Pooh) and unneutered son (Tigger - kept separetely) were both smooth haired - first agouti dutch type, latter pure agouti - neither had urinary issues.
Group 2 - 16 in all, some related, some not. Only one alive now (Old boy Ginger!) The following 3/16 had urinary issues - Sludge, Interstitial cystitis or stones.
- Maple: Aby un-neutered buff male - age 4+ - PM done - tiny gritty calculi found embedded in bladder wall. Horrendous bleeding in wee requiring Vit K injections
- Fleure: Unrelated agouti smooth haired female - diagnosed with multiple kidney stones on Xray (after removing large stone from urethra) at age 4+
- Bailey: Unrelated Chocolate/buff smooth haired unneutered male - large bladder stone age 4+ (kidneys etc OK)
Group 3: 12 pigs all but one still alive - all rescue pigs unrelated from all over the country with who knows what history! Only 2 have urinary issues (.......so far!)
- Tamarind: Female spayed tricolour (Black/Tan/White) aby - multiple stones in both ureters age 4+ so PTS
- Carson: Agouti/tan/white sheltie cross - bladder sludge.
Carson is my only bladder pig still living (well, we are going back over 18 years of history!) He was diagnosed with sludge at age aprox 2-3yrs of age , given a bladder flush and has been on a non-leafy-green diet as it appears that leafy greens make him squawk when peeing and pooing. The diagnosis/bladder flush was either 2011/2012 and I think he may need another one soon. Carson is only allowed to have fresh grass, dandelions, carrots, baby corn, parsley (in moderation) apple, pepper, dried speciality forage (including marigolds/hays etc). I have noticed that readigrass recently can make him squawk!
All the pigs in Groups 2 and 3 were/are being fed on various dried food every other day depending upon their individual circumstances: These include Gertie Guinea, P@H nuggets (great for mush mix and syringe feeding instead of CC) , and more recently Burgess nuggets and Harringtons nugget. I am just about to start introducing JR grainless feed (they are all VERY fussy individuals -each to their own preference!)
Veg wise - they always/still get veggies every other day which is alternated with readigrass or meadow/speciality hay in addition to the dried food mentioned above
Fresh Veggie mixes include by rotation:
a) spinach/romaine/parsley;
b) celery/apple/baby corn/peppers/broccoli florets
c) kale or spring greens plus cos or romaine lettuce
d) carrots
e) in summer - grass and dandelions, plantain, bittercress, and any other "forage" they deign to eat
f) any combination of the above depending upon what's in the fridge at the time!
So far i have personally been unable to determine any obvious "link" with tap water - except and insofar as it "may" have an impact on pigs with certain genetics. At the moment i don;t think we have enough information/research to be able to "predict" or "minimise"the risk of urinary symptoms for a pig - but like you it is something i would like to work towards.
Will PM you about this and further thoughts later in the week in the hope we can join forces to help "crack open" this distressing condition in our pigs.
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