Oxalic Acid and Guinea Pigs

Usually, when we talk about a food on this blog, it's something that guinea pigs can eat, even if only occasionally. In this post, we're going to start off by talking about something you should never feed a guinea pig.

The other day, the humans brought home a new food from the grocery store, and we got excited.

What is it? Can we eat it?

Why is it just sitting in a jar? Shouldn't someone be eating it?

Wow, it comes with instructions?

So it turns out that this is a type of fruit known as monstera deliciosa, or Delicious Monster. Humans have to let it sit in a jar and let the green scales fall off before it's edible for them. Before that, it has too much oxalic acid to be safely consumed. Even after the scales fall off, "Sensitive individuals (may) suffer throat irritation, urticaria and anaphylaxis," according to the Encyclopedia of Fruit and Nuts. The humans reported some tingling in their mouths after eating it. We'll have to take their word for it.

Unfortunately, keeping your guinea pig safe from oxalic acid isn't as easy as just avoiding the delicious monster. Oxalic acid is found in many different types of food. It's also found in many household plants, which is why the humans freaked out that one time I ate a lily.

So what exactly is oxalic acid? It's a chemical substance that occurs naturally in plants, and can be toxic at high dosages. When eaten, it combines with metals in your body like magnesium and calcium to form a type of salt called oxalates. The body has no use for oxalates, and so it expels them through urine. At low dosages, this is generally not a problem. However, at higher dosages, important nutrients are trapped in oxalates, preventing your body from absorbing them. Also, oxalates crystals can be sharp, which can irritate the body and cause problems, such as kidney stones. In guinea pigs, too much oxalic acid can be fatal.

As we mentioned in our post on Guinea Pig Nutrition, guinea pigs should generally eat no more than 50 mg per day of oxalic acid. Some foods that are high in oxalic acid include:

• Beet Greens (leaves) = 610 mg per 100 grams
• Parsley = 425 mg per 25 grams
• Radishes, mild = 480 mg per 100 grams
• Spinach = 970 mg per 100 grams
• Sweet Potato = 240 mg per 100 grams

Guinea pigs can still eat these foods, but in moderation--for example, maybe only 5 grams of spinach per day or less to avoid exceeding 50 mg limit.

Palestinian Guest Piggies: Hamlet and Sir Francis Bacon

We checked our email the other day, and found a submission for a guest piggy post from some guinea pigs in the Palestinian territories! We generally try to stay out of human politics- we've got enough going on with cage politics, for example, how Broccoli is always trying to steal my role as the dominant piggy. Please keep in mind that the views below belong to Hamlet and Sir Francis Bacon. If people have other views, feel free to express them in the comments section, but let's try to keep it civil. Shouting makes us run for cover in our pigloos. :-)

So without further ado, let's hear from Hamlet and Sir Francis Bacon!

-----
Marhaba, hey there, we’re Hamlet and Sir Francis Bacon. We’re brothers and Palestinian piggies, even though our human gave us clever British piggy-names. We live in Ramallah in the West Bank part of the occupied Palestinian territory with our human, an American expat, who works in aid and development.  We were rescued from a pet-prison when we were babies. It was terrifying there.  We were in a tiny glass cell and didn’t have food or water and Sir Francis Bacon had scurvy and mange. Our human brought us to a vet, but the vet didn’t even know what we were, so he wouldn’t treat us. Sir Francis Bacon almost died but our human worked really hard to find a vet who knew about piggies, and that vet gave us ivermectin shots and now we are six months old and really fat and healthy!
                                     

Our human is good like that. She gets really mad at the pet-prison we came from, but she knows it’s hard to fight for humane treatment of piggies when people in Palestine don’t have basic rights. We hope we can live with her forever but if she leaves here we don’t think we can go with her to the United States. There are lots of checkpoints and much like the Palestinian people, we don’t have pig-ports that help us travel abroad.
We live in a giant pig-pen, with two separate pig-loos, it’s like a piggy villa! We love it so much that we never want to come out. Unless there’s a plate of food involved. We love to read about Lola and Broccoli and Buffy and we try a lot of the foods they tell us about. We love mint, parsley, fennel, tomatoes, cucumbers, carrots, apples, strawberries, and corn, especially the husks. We don’t like bananas and figs so much. We don’t think there are many more piggies in Palestine, and we certainly hope there are no piggies in Gaza right now. It makes us sad to think about the plight of humans there. We hope that humans all over the world will start caring more about each other and of course about piggies and other animals, even the wild dogs that bark all night and scare us. We know it’s not their fault.

                                     

Thanks for reading about us, we feel really lucky to be able to tell our story and share our pig-spective on our favorite blog!

Product Review: Oxbow Timothy Twists

Today we're reviewing Oxbow Timothy Twists, another chew toy in their Timothy Club line of products (which also includes the Timothy Carrot and Timothy Mat). Keep in mind that while chew toys are great (or can be), they are no substitute for fresh hay for keeping our teeth ground down to a reasonable length.

One advantage of this product is that it's just timothy hay; as Oxbow's site proclaims, it "Contains no chemicals, wire, or thread for your small pet to ingest." As long-time Cavy Savvy readers know, one sure-fire way to get a bad review from us to have something obviously unhealthy or even harmful in your pet products, such as burlap, peanuts, wood dust, etc. After establishing that it's safe, the next question, of course, is: Will we like it?

I hope we like these better than the Seagrass Twists.

I'll bite. (Literally.)

Looks like I started a trend.

We gave these a chance at first, but our interest quickly waned. We'll still occasionally give these things a little nibble, but they certainly aren't our favorite chew toy. We'll give Oxbow Timothy Twists 3/5 stars.

Can Guinea Pigs Eat Currants?

Currants come in different colors, including black, red and white. All three have a tart flavor. Black and red currants are separate species, while the white currant is an albino variation of the same species as the red currant. The white kind is slightly sweeter than the red kind. Currants are closely related to gooseberries; hybrid currant-gooseberries are called jostaberries.

We should also point out that there's another food referred to as a currant, which are small, dried Zante grapes. These are also known as Zante currants and Corinthian raisins, and are unrelated to the berries we're reviewing in this post. These dried grapes ended up being called "currants" when they were exported from Greece to the United States, and the word "Corinth" was mistranslated as "Currant."

Currants are native to Europe, so they might be a bit hard to find in the United States. You might want to check your local farmer's market if the grocery store doesn't have them. We can have currants about 2-3 times per week in moderation.

New berries! I bet I'll like the red ones better!

Munch, munch...

Hey, those are my berries. Back off!

Oh no! I lost control of the plate!

That's not good! Broccoli was able to take over the plate while we were eating currants. I hate to say it, but I think he might be winning the battle for dominance!

Cage politics aside, I have to say the berries were delicious. The taste has been described as "lightly sour raspberry," and we love raspberries! We give currants 5/5 stars!

Ask A Guinea Pig: Are Guinea Pigs Afraid of Thunderstorms?

It's time for another installment of Ask A Guinea Pig, where we answer your questions from the comments section! riordan77piglove asks: "Do guinea pigs get scared from thunder and lightning? I'm pretty sure that it is a little scary."

Great question! Yes, guinea pigs can get scared from thunder and lightning, just as we would from any loud noise. Sometimes, one of the humans will sneeze or cough, and we'll immediately run for cover! They don't understand what the big deal is, but keep in mind that we're pretty small and defenseless in comparison to a human. When they make sudden loud noises, our instincts kick in and we bolt!

In terms of loudness, sneezes are perhaps 90 decibels, while a thunderclap can be as loud as 100 to 120 decibels. Some other things that fall within this decibel range are motorcycles, power saws, and rock concerts.  In addition to being louder than sneezes, we may have to put up with lots of thunderclaps in a row, which we wouldn't have to do with sneezes (unless the human is having a sneezing fit, in which case, you should leave the room and stop scaring your poor piggies!).

We found that one person claimed, "I have heard of pigs literally getting scared to death," although we haven't been able to find any evidence of that actually happening. (Another person speculated that they would probably have to have a preexisting heart condition for that to be possible.) Keep in mind that reactions may vary. Some piggies aren't phased by thunderstorms, while others will huddle together, shaking in terror.

So what can you do to keep your piggies calm during a storm? Here are some tips:

• Make sure your guinea pig has at least one piggy companion. We tend to feel safer in numbers.
• Make sure we have a pigloo, or other enclosed space where we can hide. We tend to find it comforting if we can put distance and covering between us and things that make scary loud noises.
• You could try feeding your guinea pigs vegetables and/or holding them if they like being held. (Buffy doesn't like being held, and wouldn't find this comforting.)

Hey, we can't all hide from loud noises in the log! Someone is going to have to pick another hiding spot.

These tips are also applicable to fireworks, by the way. (I wish we had answered this question before July 4th!)

How does your guinea pig react to thunderstorms? Does anything calm help them down? Let us know in the comments section!

Guinea Pig Nutrition

When we rolled out our food list, we sought feedback from the major guinea pig forums. One critique we heard is that there was not enough information about the overall planning of your guinea pig's diet. We included the feeding frequencies recommended by the diet expert at guineapigcages.com on our list, but those are just rough guidelines for that particular food. For instance, apples are a 1-2 times per week food, so you know that if you're feeding your guinea pigs apples every day, that's way too much. However, beyond not exceeding these feeding frequencies per food, how do you figure out exactly what to feed your guinea pig each day, and in what quantities?

Sources for Information
As it turns out, planning your guinea pigs' diet is a pretty complicated subject. For humans, there are calorie tables and nutrient tables, which spell how much food, and how much of each nutrient, a human should eat. We didn't find anything exactly like this for guinea pigs, although our research came across two academic/scientific sources that came closest:

• Juan M. Navia and Charles E. Hunt (1976), "Chapter 17: Nutrition, Nutritional Diseases, and Nutrition Research Applicatins," in Joseph E. Wagner & Patrick J. Manning, eds., The Biology of the Guinea Pig, Academic Press.
• Note that while there is a lot of good information in this source, it's rather old at this point. There may be newer studies than what they have cited. 
• National Research Council (1995), Nutrient Requirements of Laboratory Animals, Fourth Revised Edition.
• Regarding this source, Guinea Lynx points out the following:
• "Cons: some data is over 50 years old, other data is extrapolated from rat studies (the authors of this article encourage more research). Some of the specific diets recommended are only suitable for laboratory animals. The authors note the high protein, low fiber diet typical of a laboratory animal and mention that a cavy's diet in the wild consists of much more fiber and green vegetation."
• "A complete list of requirements is printed on page 104. Keep in mind, these are not daily requirements but instead the amounts of vitamins and minerals they recommend adding to a kilogram of food to provide proper nutrition. Your pig will only eat a fraction of a kilo per day."
• We would also call attention to the fact the table is called "Estimated Nutrient Requirements for Growth for Guinea Pigs," and their disclaimer on page 105: "The data are not sufficient to differentiate between adult maintenance requirements and growth, pregnancy, or lactation requirements; hence, estimates are provided for growth only." In other words, if you look at the humans tables for calories and nutrition, it differentiates based on children and adults, but this guinea pig food table can't do this.

We also looked at what other information we could find online, looking primarily at guineapigcages.com and Guinea Lynx. Using these sources of information, we want to share what we've found so far. Please note that this is just the best information we were able to find and understand, and should not be regarded as indisputable fact about what guinea pigs should eat! We may post on this topic again to revise these guidelines as we learn more. In addition, we recommend talking to your vet about your guinea pig's diet before making any major changes.

Keeping all this in mind, here is what we think you should know about planning your guinea pig's diet:

Diet Overview

• Water: Guinea pigs need 100 ml water per kilogram of body weight. (Give them unlimited access, of course. Don't just measure out this amount. However, do be concerned if they seem to be drinking significantly less than this amount.)
• Food: The diet expert at guineapigcages.com recommends: "50% hay, 40% veggies and 10% high quality pellets."
• Hay: Guinea pigs need unlimited access to quality grass hay. (If you need to know how much to buy, one person estimated that their guinea pigs "will eat/waste/use about 1/4-1/2 a pound of hay per day.") (That is, about 113-227 grams.)
• Veggies: about 1 cup of vegetables per day (including 2 servings of leafy greens and 1 serving of non-leafy green veggies daily, and fruits no more than 1-2 times per week in moderation). However, keep in mind that a cup is a measure of volume, and grams are a measure of weight. Since most of the nutritional requirement information we've found is by weight, it's probably a good idea to have a rough concept of what this converts to.
• According to Livestrong.com, for raw veggies, 1 cup converts to about 8 ounces, or about 227 grams. This seemed a bit high to us, however, so we decided to do an experiment to test this for ourselves. We put a measuring cup on a scale, and then filled it with various produce from the fridge (lettuce, zucchini, and gooseberries) to see how much it weighed when it reached the top. It weighed 100 grams, just to give you a rough idea of how much a cup of mixed fruits and veggies might weigh. 
• Note that the actual weight in a cup will vary by food. If you look at our food list, you'll see that most of the foods have a link to the USDA's National Nutrient Database for Standard Reference. This will let you know how many grams are in a cup of each food. It can be as low as 36 grams for a cup of collard greens and as high as 236 grams for a cup of passion fruit, but in general, the numbers mostly seemed to cluster around about 75 - 150 grams per cup. The juicy fruits and veggies tended to weigh more, while the leafy ones tended to weigh less. 
• Pellets: Oxbow Cavy Cuisine pellets are recommended. They recommend 1/8 of a cup of pellets daily. According to our humans' scale, this is about 20 grams. (This is also how much Guinea Lynx estimated a couple tablespoons of pellets to weigh.)

Key Nutritional Needs:

• Vitamin C: Adult guinea pigs need 10-30 mg of Vitamin C per kilogram of body weight per day. Remember, 1,000 grams = 1 kilogram, so unless you have an unusually large or small guinea pig, you'll probably want to feed your guinea pig around 25 mg per day. 
• Low vitamin C can cause a condition called scurvy. This is a very serious condition that can affect bones, blood vessels, adrenal glands, and more. If your guinea pig has scurvy, you'll want to increase their vitamin C intake to 50 mg/day.
• It's also possible to cause a condition called pseudo-scurvy if you give large doses of vitamin C (around 100+ mg per day), and then suddenly cut back to a smaller dose. This is a temporary condition, and nowhere near as serious of a concern as scurvy is. 
• Vitamin A: There is limited information currently available on guinea pig Vitamin A requirements. Some older studies suggested that 6.6 - 9.9 mg of vitamin A per kilogram of body weight per day is best. (Navia & Hunt, p. 241). However, the diet expert at guineapigcages.com starts warning about vitamin A being high on foods that have 316 mcg per 100 grams (equivalent to 0.316 mg, much lower than the Navia & Hunt information), so we're going to recommend avoiding feeding more than 300 mcg per day.
• Sugar: We haven't been able to find studies on how much sugar guinea pigs can have per day. However, on our favorite food chart, the diet expert at guineapigcages.com starts warning about high sugar levels for food with 3.8 grams per 100 gram servings. The highest sugar amount in an "almost daily" food is 2.4 grams per 100 gram servings. Therefore, until better information is available, we're going to recommend avoiding feeding more than about 3.8 grams of sugar per day on average, and try to aim for 2.4 grams or less. It might be okay to go a little over by feeding fruit as treats occasionally, but try not to go too far over, and not too frequently. 
• Calcium & Phosphorous: It is recommended that you keep the ratio of calcium to phosphorous to be between 1.5:1 and 2:1. Guinea Lynx has an Excel Spreadsheet you can use to calculator calcium-phosphorous ratios more easily. 
• Younger guinea pigs need calcium for bone growth. After six months, however, calcium intake should be lowered; keep to about a 0.3% level of calcium to prevent health issues.
• Based on a Guinea Lynx sample diet for avoiding stones, calcium from fruits and vegetables (not counting pellets) can range from 64 mg - 107 mg per pig per day, and phosphorous from fruits and vegetables (again, not counting pellets) can range from 39 mg - 71 mg per pig per day. 
• Magnesium: "the magnesium requirement is 1 to 3 g/kg diet, 1 g/kg diet being the minimum requirement" (National Research Council, p. 113)
• The National Research Council notes that: "Requirements for calcium, phosphorus, magnesium and potassium seem to reflect interactions among them." We have seen recommendations for the calcium-phosphorous ratio, but it's probably even more complicated when magnesium and potassium are taken into account.
• Oxalic Acid: Guinea pigs should eat no more than 50 mg per day.
• Too much oxalic acid can cause renal failure.

Other Nutritional Needs:

• Vitamin D: Some research suggests 500-750 IU of vitamin D per kilogram of body weight per day. (Navia & Hunt, p. 242)
• Vitamin E: The little evidence available on vitamin E suggests 1.5-6.0 mg per day (Navia & Hunt, p. 243).
• Thiamine: 2 mg per kilogram of body weight per day (Navia & Hunt, p. 244).
• Riboflavin: not determined (Navia & Hunt, p. 244).
• Niacin: about 10 mg per kilogram; also depends on quantity and quality of dietary protein (Navia & Hunt, p. 245).
• Pyridoxine (Vitamin B6): about 2-3 mg per kilogram of body weight per day (Navia & Hunt, p. 245).
• Folic Acid: young guinea pigs: 3-6 mg per kilogram of body weight per day, less for adults (Navia & Hunt, p. 245-6).
• Pantothenic acid: 20 mg per kilogram of body weight per day (source: Navia & Hunt, p. 246).
• Choline: 1.0-1.5 grams per kilogram of body weight per day (source: Navia & Hunt, p. 247).
• Other nutrients mentioned as important by the National Research Council, but difficult to convert into a daily requirement since they are expressed in amounts needed to be added to a kilogram of food, include (but are not limited to):
• Protein
• Essential fatty acids (n-6)
• Fiber
• Arginine
• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

Planning Your Guinea Pig's Diet:

• Although a wide variety of nutritional requirements are mentioned above, in order to make your planning more manageable, we recommend focusing in on just a few of the key aspects that were identified by the guineapigcages.com diet expert: Sugar, Calcium, Phosphorous, Vitamin C, Vitamin A, Oxalic Acid, and the Calcium-Phosphorous Ratio. (It's probably safe to assume that if you feed a quality pellet and a varied diet, the rest will take care of itself.)
• Also keep in mind that cruciferous vegetables contain a substance called raffinose, which can make guinea pigs gassy and bloated if overfed. So try to limit the amount of these these, even if the numbers look good in these key indicators.
• Our food list provides links to sites with nutritional information; the USDA website is the preferred source for nutritional information since they are authoritative and relatively comprehensive.
• Oxalic acid information is missing from the USDA website, however. Sources where you can find oxalic acid information include the guineapigcages.com food chart, the Guinea Lynx oxalic acid chart, the USDA's Agriculture Handbook, LithoLink Corporation, and oxalicacidinfo.com.
• Trying to calculate the nutritional aspects of guinea pig pellets is very complicated. The standards for nutritional labeling are set by an organization called the AAFCO. Pet food labels use these standards, presenting information as "Guaranteed Analysis," which is very difficult to convert to the actual amount of nutrients in a given amount of pet food. For simplicity's sake, we just used the Guinea Lynx food chart generic guinea pig pellet numbers. We would have liked to have the actual numbers for the pellets we use, though.
• Using the guidelines suggested by our research, we decided to analyze an entry from a sample veggie menu from the diet expert at guineapigcages.com for nutritional content to see how well our draft guidelines matched up:

Our notes: 1. The gram amounts fall within our suggested range. 2. The vitamin C amounts are above our suggested minimum range, but is nowhere near the amount where pseudo-scurvy could be a problem. 3. The vitamin A amounts are under the suggested 300 mcg limit before pellets. 4. The sugar amounts are under our suggested maximum. 5. The calcium and phosphorous amounts are below our ranges for the fruit and vegetables portion of the diet.  However, being too high seems to be more of a concern than being too low, and the pellets will certainly add to this. Unfortunately, we only have generic pellet numbers. 6. The calcium-phosphorous ratio was off until pellets were factored in, which then put them within the ideal range. 7. The oxalic acid was a little high. The green beans were the biggest contributor to this. We think substituting one of the two green beans for another food that's lower in oxalic acid would have been a good idea. 8. Sources used in making this table included the USDA site, guineapigcages.com chart, and the Guinea Lynx chart (for pellet information).

• Once you've found a diet that's has sufficient amount of the good stuff and not too much of the bad stuff, don't just keep feeding your guinea pigs the same stuff over and over again. You'll want to maintain variety in your guinea pig's diet.
• It is better to have two meals a day for your guinea pigs rather than just one big meal. 

Final Thoughts
We want to emphasize again that we are not veterinarians, and this is by no means the last word on the subject. We are just presenting the best information we were able to find so far on how to plan your guinea pig's diet. Going forward, we would love to hear from veterinarians and other experts on guinea pig nutrition for feedback on these guidelines.

We would also like to see nutritional information on specific pellet products and types of hay presented in the same easy-to-read format as the food charts. It was sometimes unclear whether particular guidelines were applicable just to the veggies portion of our diets, or to the entire diet including hay and pellets. 

Once we feel more confident in our guidelines, perhaps we can do some posts with sample diets based on the guidelines, similar to the ones guineapigcages.com and Guinea Lynx made. Let us know in the comments section if you'd be interested in seeing this!

*Note: We did ask the humans for help with this post, since one of them has a Ph.D. and is a professional researcher, in case you were wondering. He didn't seem to mind, though. We rewarded him in snuggles. 

Product Review: Oxbow Bene Terra Organic Guinea Pig Pellets

Some nutritionists have called breakfast the most important meal of the day. For years now, we've been loyal fans of Oxbow's Essentials - Adult Guinea Pig Food for breakfast; it gives us the energy we need to scamper around, chew on things, and then take naps. Today we're reviewing a new type of pellet: Oxbow Bene Terra Organic Guinea Pig Pellets. Will this new pellet unseat our current pellets as our #1 breakfast choice?

Oxbow and organic. Both good signs!

Munch, munch...

Hey, it's pretty good!

The instructions for these pellets are the same as the other ones: 1/8 a cup per day per guinea pig. The pellets themselves look and taste pretty similar to the other ones as well (although we read that some other piggies have a preference for one or the other).

Some people may ask: Does buying organic matter, or is it just hype? Well, according to the Mayo Clinic:

•  Nutritionally, there does not appear to be a significant difference between conventional and organic produce.
• "Organic produce typically carries significantly fewer pesticide residues than does conventional produce."
• Organic produce restricts the types of food additives that may be used.
• "Organic farming practices are designed to benefit the environment by reducing pollution and conserving water and soil quality." 

We should also point out that there are plenty of studies critical of organic produce. However, the Mayo Clinic seems like a reputable source, and they're willing to state that organic produce at least contains less pesticides, that's good enough to make use prefer it over conventional.

Based on the organic label alone, you would think we'd be ready to switch. However, we also have to point out that there were some ingredients in this pellet that concerned the diet expert at guineapigcages.com:

• Limestone - no apparent reason for its inclusion.
• Wheat straw - not very nutritious.
• Sunflower meal - contains oils that can be fattening.

In addition, someone else was concerned about the higher calcium levels in this pellet. Too much calcium can lead to bladder stones, so this is a bit concerning. We'll have to keep a closer eye on the amount of calcium in our diet while we're eating this stuff.

So here's our verdict: Organic ingredients are a good idea, but Oxbow should have just kept the same formula as their other pellets (Oxbow's Essentials - Adult Guinea Pig Food). There were a few concerns raised about this formulation which prevent us from switching pellets, mainly the higher calcium content. These are good pellets, but why settle for less than the best? We'll give Oxbow Bene Terra Organic Guinea Pig Pellets 4/5 stars, but recommend you stick with the 5-star pellet (again, that's Oxbow's Essentials - Adult Guinea Pig Food).

Cavy Savvy's Father's Day 2014 Giveaway Winner

Using a random number generator, we chose a winner from all valid entries to the Cavy Savvy Guinea Pig Father's Day Giveaway. And the winner is... Rose Marz!

Congratulations, Rose! You just won Oxbow Animal Health Harvest Stacks-Western Timothy Hay! Please email us in the next 30 days with your mailing address to cavysavvyaguineapigblog@gmail.com and we will mail you your prize.

Thank you to everyone who entered. If you didn't win this time, don't worry, we will have more giveaways in the future. Be sure that you are a follower of Cavy Savvy if you want to be considered for future giveaways. To follow us, just click the "join this site" button on the right.