So, a few months ago I switched Jax to Renew Gold - he is n/P1, so starch/sugar sensitive. He was on it for a couple of months, then the feed was back ordered so I had to switch to something else for almost a month - it didn't work, and he's now back on Renew Gold. The NSC is just under 17% (!!) which terrified me, but after doing some research, I'm not nearly as nervous about it now (plus he does amazing on this feed). So, this post is not intended as a "this is what you need for your horse!" type of post, this is informational, and may help you with your feed decisions
I've been reading about the Glycemic Index, here's a quick quote for you guys:
"Glycemic index is a number. It gives you an idea about how fast your body converts the carbs in a food into glucose. Two foods with the same amount of carbohydrates can have different glycemic index numbers.
The smaller the number, the less impact the food has on your blood sugar.
55 or less = Low (good)
56- 69 = Medium
70 or higher = High (bad)"
Source: Web MD
Jax has always seemed to be hypoglycemic since becoming symptomatic - like his blood sugar levels were always too low (no energy, would become shaky with work which would turn into spasms if he didn't eat), and it would quickly be fixed with a nibble of grass (especially on the trails). Higher fat in his diet helped, but he still needed several quick blood sugar boosts on longer rides. He's now on a higher fat diet with this feed (about 1 lb) + 1/2 cup of canola oil. The Renew Gold has 17% NSC and that high number comes mainly from the sugar in rice bran. Now here's where it gets interesting - rice bran, while high in sugar, has a very low glycemic index, so it doesn't cause major blood sugar spikes like other carb sources. If glucose isn't being dumped into the blood stream, then it's not being converted into glycogen. This may be why there are so many anecdotal references to rice bran being good for PSSM1 (even though we are taught the high NSC is bad). Here's some stats from an interesting article on the Glycemic Index regarding horse feeds from BarrelRacingTips.com:
High Glycemic Index:
Sweet Feed: 123
Beet Pulp + Molasses: 95
Low Glycemic Index:
Beet Pulp Dry: 46
Alfalfa Hay/Cubes: 23
Bermuda Grass Hay: 23
Rice Bran: 16
Rice bran actually has a lower NSC than hays, beet pulp, and alfalfa pellets. I'm starting to understand why he's been doing so well lately, and why he again started to do worse on the other feed. So just remember, while NSC percentages are EXTREMELY important, and we definitely should not ignore them, there is always more to the story. With more time on this feed, I may find that it doesn't work long term. But for now, he's doing great, and I'm not changing again until I have to!
More information that I've found while looking up hindgut issues, as my boy's stomach seems off from being on the other feed: Renew Gold's main ingredients are rice bran, coolstance copra, and flax. Here's some info I just found on copra and glucose:
"... unlike grain based feeds, CoolStance does not cause a spike in insulin or glucose after it is eaten. This means CoolStance is the ideal feed that can be fed twice a day to suit our busy lifestyles, and does not cause metabolic upset in your horse caused by spikes in insulin and glucose."
So apparently the two main ingredients do not cause insulin spikes, therefore reducing glycogen spikes as well (copra is only 11% NSC). Here's the page with this information for Coolstance Copra.
My current feed plan for my boy:
Free choice grass hay, not soaked
1 lb Renew Gold
*1 lb ADM Metabolic Pellets (11% NSC)
1/2 cup canola oil
**1,400 IU natural Vit E
2 tbsp Mag Ox
1 tbsp MSM
2 tbsp salt
54g pea protein
The feeds and supplements are soaked into a nice mash and split into two feedings - half before tacking up and working, and half after work.
* Renew Gold is not a fortified vitamin/mineral, it is a fat/protein/amino acid supplement. I use ADM Metabolic Pellets with it as it has a great vitamin/mineral analysis and adds bulk to his feed.
** The Vitamin E numbers look low, but there is 500 IU of natural Vitamin E in the ADM feed, and rice bran has Vitamin E but I'm unsure of the amount, so my boy is getting at least 2,000 IU of Vitamin E (with minimal grass included in his diet). Any amount over 4,500 IU makes him extremely spooky, and as of now this amount has him nice and calm, and feeling good. As winter approaches and the little grass that he gets is no longer available, I may have to up the amount of Vitamin E.
I also have about 2,600 mg of L-Glutamine (an amino acid) in his diet which seems to help keep his hindgut happy (I'm surprised he had issues on the other feed while still on L-Glutamine). Now that he's on the Renew Gold again, he'll stay on this until he starts to run low, and then I may wean him off it.
BTW, I swear I'm not a rep for any of these companies...
Other noteworthy comments:
Jax is on a full work schedule of 6-7 (mostly 7) days of exercise a week. Horses on lower work schedules may not need the same kind of energy sources.
Comparisons between Jax on Renew Gold, and off:
- Before Renew Gold (and while on the other rice bran-based feed), he had very little canter, and not much trot.
- On Renew Gold, not only can he canter but his canter is nice and smooth, he can carry it for any length of time, and he even competed in a fun show (just a bunch of friends getting together and running our horses around for about 4 hours playing silly games - the day after he went out for a long trail ride and easily stayed up with the other horses so he was not sore from this endeavor.
- Before Renew Gold (and while on the other rice bran-based feed), he had stamina, but without stopping to eat something during longer rides he would get shaky. He also had a hard time keeping up with other horses on any length of trail rides (he used to be the one in the front at all times because he's faster than the other horses).
- On Renew Gold, I still let him stop and nibble grass, but not nearly as much, and it's more as a treat now than something he "needs" to get through the ride. He easily keeps up with other horses, through all terrains, and sometimes leaves them behind with his big walk, trot, and canter.
- Before Renew Gold (and while on the other rice bran-based feed), he couldn't handle being cold or rained on (even in warmer weather) - it would cause him to have muscle spasms.
- On Renew Gold, he's not been in cold weather since starting this feed, but he has been in rains and storms with no spasm issues.
- Jax has had very tight muscles in his back, shoulders, neck, and hindquarters for the 6 years I've had him. Here are his back muscles now: