Urinary Blockages in Pet Goats – Preventing Urolithiasis….
Urolithiasis is a common condition in lifestyle block goats and sheep. If your goat or sheep has suffered from urolithiasis (stones in the urinary system) then you will be well aware that this disease process causes a lot of heart ache. If you’ve been following our recent posts on urolithiasis then you now hopefully have a better understanding of the following topics:
– What this urolithiasis?
– The clinical signs to watch out for
– Tools to help diagnose urolithiasis (for vets an owners)
– The immediate medical and surgical options available to you in the case of an emergency case of urolithiasis.
Today’s post will be the most important post surrounding this topic. Why? Because preventing diseases is what The Lifestyle Vet is all about, and because today we will be discussing how best to prevent urolithiasis in your beloved goats.
To start with, it is important for you to know that there are a variety of stones that can form within the urinary tract of your goat and sheep. Since the composition of each these types of stones is different, different factors contribute to the development of each of these stones.
Common types of urinary stones in goats and sheep:
There are THREE different kinds of urinary stones that goats can get in NZ, which are:
– Phosphatic calculi (also known as struvite)
– Calcium carbonate
– Calcium oxalate
1. Phosphatic stones
As the name suggests, these stones contain high quantities of phosphate. Phosphatic stones form when a combination of phosphate, magnesium and ammonium come together to form little white granular stones that are crumbly when touched.
In healthy goats and sheep that are eating pasture and browse and are ruminating (what they are meant to do), the phosphate that is ingested is recycled into the saliva. Saliva production in ruminants is key as it enables the animal to remove phosphate from the body. Not only are grain based feeds (goat grain, pellets etc) high in phosphorous and low in calcium, but they also reduce the amount of saliva that the animal produces, and consequently the animal spends less time ruminating. Less rumination means less saliva production. Since the animal can no longer excrete the majority of its phosphorous via the saliva, it starts having to excrete it in the urine instead. All of a sudden the bladder now contains urine that is high in phosphate and this phosphate starts to bind with ammonium and magnesium to form little struvite crystals.
How can you try prevent the formation of phosphatic stones?
– Unless you absolutely need to feed grain or pellets to your sheep or goats (to increase body condition) DON’T
– If you must feed grain or pellets (for whatever reason) then make sure the dietary Calcium to Phosphorous ratio is 2:1 – a calcium to phosphorous ratio less than 1.5:1 will increase the risk of phosphatic stone formation.
– Make sure the magnesium content of the feed is at recommended levels
– If you are feeding grain then add salt – 3-5% of total dry matter can be added as salt. This will cause the goat to drink more water and increase the amount it urinates, therefore reducing the risk of stone formation as the urine is diluted.
– Add a urinary acidifier to the diet (ammonium chloride) – please talk to a goat veterinary nutritionist / goat vet about this for more information.
– Always provide large volumes of good quality clean water
2. Calcium carbonate & calcium oxalate stones
These stones form when your goats and sheep are provided with a diet that is high in calcium. These stones are gold in colour and look like little BBs. Legume based hays and grasses are high in calcium and can predispose to the formation of calcium carbonate stones. Examples of these include lucerne, alfalfa and pastures that are clover dominant. Calcium stones can also form if you are feeding your goats and sheep grain or pelleted mixes that are meant for lactating animals. Many commercially available feeds intended for lactating animals have a calcium to phosphorous ratio of 3:1 or more. Providing these feeds to your non-lactating lifestyle block goats and sheep is very risky. Please read the packet carefully and question the calcium to phosphorous ratio of any commercial feed prior to buying it.
How can you try prevent the formation of calcium carbonate & calcium oxalate stones?
– Avoid feeding your male weathered goats and sheep legume based hay (alfalfa or lucerne). Females can be fed legume based feeds but avoid feeding hard feed intended for lactating animals when you are feeding legume hays. If you are feeding females then make sure that there is no way the males can gain access to this feed.
– Avoid the perfect storm – lucerne hay + pelleted mix for lactating animals = urolithiasis
– Feed grass/meadow hay rather than legume hay
– If you are feeding legume hays or pelleted feed then add salt – 3-5% of total dry matter can be added as salt. This will cause the goat to drink more water and increase the amount it urinates, therefore reducing the risk of stone formation as the urine is diluted. You can also dissolve the salt in water and spray it onto the hay.
– Always provide large volumes of good quality clean water
– Avoid feeding plants that are high in oxalates (rhubarb, peanuts, pig weed)
Other preventative strategies:
– Clean water containers regularly
– Make sure the water is palatable and use dark liners so that the water is not too cold (goats are fussy and don’t like water that is too cold in winter)
– If your water containers fill automatically, make sure they are working at all times.
2. Increase salt intake to promote thirst
– Add salt to mixed rations so that 4-5% of total dry matter is salt (this is anywhere between 0.4-1g of salt per kg of the animal’s body weight per day)
– You can spray salt water onto the hay and let it dry
– Use a non-iodised salt and provide salt blocks or loose salt
3. Check that the feed you are using is appropriate
– Body condition score your animals regularly get your vet to teach you how to do this
– Unless then are a body condition score of 3 or below you probably don’t need to supplementary feed with hard feed
– If you are supplementary feeding with hard feed then check that what you are using is appropriate for the physiological needs of your animal (eg growing, lactating, pregnant etc)
– If in doubt, ask a professional and make sure that this professional is qualified in the field (qualified animal nutritionist for the species you are enquiring about, or a vet experienced in the field)
4. Avoid early castration if possible
Early castration may increase the risk of urolithiasis. Testosterone is required for adequate urethral development, and therefore a castrated male will mature with a smaller urethral diameter compared to an intact male. To avoid this, it has been recommended to avoid castrating male sheep and goats intended as pets (that may be hard fed) until they are 8 weeks of age. When castrating animals over 2 weeks of age, please ensure that pain relief strategies are implemented and consult with your veterinarian beforehand.
Finally, why are some goats and sheep that are fed hard feed prone to obstructing whilst others don’t appear to be affected? There may be genetic differences at play, where one animal’s mineral metabolism may be different to another’s. More research is required in this field. We hope that the above information has been somewhat helpful, and that it can help reduce the incidence of urolithiasis in pet goats and sheep in NZ.
The Lifestyle Vet – Providing an exceptional level of veterinary care for your beloved lifestyle block pets.