Just How fast do they grow?
When discussing heritage or non commercial breed hogs there is no hot button topic like growth rates . And especially when discussing Meishans this seems to be a lively topic even among A.M.B.A. members. And there is no doubt that different feeding and nutrition profiles seem produce wildly different results even among pigs with identical genetics. As the effort to preserve this breed gathers steam and as people evaluate the breed for their own farms it is appropriate to look at the subject in a little more depth. However the study data and real life experience provided here applies ,in my experience to a number of heritage breeds . Especially smaller, slower growing, hobby or homestead lard breeds like AGH and KK. In fact studies quoted in this post range from Meishan specific to other articles and studies on dietary impact in commercial and confinement pigs.
The Growth Engine in Swine
Growth in any livestock is an engine. That engines capabilities are limited by the base genetics of the animal. And nutrition is the fuel that drives that engine. The final factor is stocking density,pasture quality and pasture recovery rates. However even within those base genetics there is a significant possibility of a wide variance in growth rates based on nutrition and the potential impacts of stocking density. Members are reporting variance so wide as to cause some to question the data of other breeders. However my personal experiences fueled by these discussions have lead me to a wealth of research that points to all parties being accurate given the environmental and genetic factors of their farm.
Nutrition: The fuel for growth is nutrition.And in this light we are talking specifically about not only the quantity of food but the digestibility and bio-availability of nutrients. And we are talking about what stage of animal we are feeding. That is growing piglets, gestating and lactating sows and maintenance diets for adult boars or sows are all different feed and nutrition profiles for the Meishan breed. As small land holders look more intently at lard breeds as a potential viable options feed costs (especially when dealing with longer grow outs ) become important. And more and more small holders( with the encouragement of their breeder associations) turn to hay, dried alfalfa cubes and pellets, spent brewers and distillers grains as dietary staples for all of their pigs. Fueled by the idea that pigs that can grow on quality pasture can also grow on the dried form of that pasture (hay) social media sites are laced with testimonials of pigs that can be raised(and grown)efficiently on hay. In addition to hay with the recent explosion of micro craft breweries and distilleries previously unavailable quantities of spent grains are now readily available often for the cost of gas to pick them up. Finally feed rooms stocked with Alfalfa pellets and cubes originally bought for ruminants or equine often find their way to the homestead hog.
On my own farm I used spent grains liberally with both my American Guinea Hogs (which I previously raised) and my current Meishan herd In both cases the pigs looked good. But in both cases the growth of piglets was negatively impacted. After my experience with AGH one would wonder why I would introduce grains again to my Meishans? Well somewhere mixed in with the facts of the breed are the legends of the breed. One of which is that Meishans process fiber much better than domestic breeds. And while Meishans do eat fiber eagerly , in the case of digestibility of vitamins and most nutrients, they are no different than domestic commercial breeds. The higher the levels of fiber in their diet actually blocks the absorption of nutrients and vitamins. The very fuel for the growth engine. And there are studies that prove this fact both for swine in general and Meishan in particular. I offer the following links and excerpted quotes for your review:
Digestibility of High Fiber Diets by Chinese Meishan Pigs A 1990 UN FAO Study comparing the ability of Meishan Piglets (as compared to Landrace piglets) to absorb nutrients when exposed to increasing levels of dietary fiber
Relevant Excerpt ” … the apparent digestibility of diets containing 0, 5 and 20% of alfalfa meal was studied with 2-months-old pigs of both breeds. Nutrient digestibility in both breeds progressively decreased with increasing alfalfa. Meishan pigs showed higher digestibility of crude protein and crude fat than Landrace pigs. The digestibility of nitrogen-free extract, crude fiber, neutral detergent fiber, acid detergent fiber, cellulose, and hemicellulose by Meishan pigs was lower than that by Landrace pigs. Total digestible nutrients in diets containing 0, 5 and 20% alfalfa meal were 75.7, 75.0 and 63.7 for Meishan pigs and 76.3, 75.3 and 62.7 for Landrace pigs, respectively. These results indicate that there is little difference between Meishan and Landrace pigs in the utilization and digestibility of nutrients”
Relevant Excerpt “Studies have shown that for every 1 percent of extra fiber that is added to the diet, the digestibility of protein, energy, and dry matter decreases by at least 1 percent. A recent study at North Carolina State University has shown that by formulating pig feed so that it is low in fiber (5.5% NDF), waste production can be reduced by 35 percent compared to a regular corn-soybean meal diet (10% NDF) and by 58 percent compared to a diet supplemented with 20 percent soybean hulls (18% NDF).”
Relevant Excerpt “In pig nutrition, we take a different view. In the young, which has limited feed intake capacity, the bulkiness of higher fiber diets often leads to slower growth rates and poorer feed efficiency. Therefore, fiber levels are often kept quite low in diets of the young pig; however, as the pigs grows, fiber levels can be increased because feed intake capacity increases in relative terms.”
Want more? Just Google “Impact of High Fiber Diets on Swine Growth Rates” and you will have hours of illuminating reading.
Its important to note that most premixed feeds and social media “experts” suggest a grower ration with up to 15% crude fiber is just fine. Higher fiber actually blocks the nutrients you are paying for in your remaining feed source. They pass through your pig undigested. Your growth fuel is leaking out the backside of your pig. Recently I got inputs from two different Meishan breeders who received piglets from my farm from the same litters. Both conscientious about feed quantity. Breeder A only allowed growers to eat bits of their bedding and supplemented their pasture nutrition aggressively . At 9 months Breeder A had a hanging weight of 242 lbs.Hanging weights calculated head on ,trotters on,skin on . Breeder B ,with piglets from the exact same litters, had a projected hanging weight (based on previous butchering) of about 155 lbs at 12 months. Breeder B feeds hay on an almost free choice basis.So grower A achieved 87 more pounds at slaughter in three months less time. That is a over a 50% increase in yield in less time. From the same genetics! This is the most extreme variance in growth I have been aware of to date. And yes there are genetic variances in the growth engine within the same litter. But to be sure anytime I find a breeder feeding hay,brewers grains or high fiber to Meishan piglets I find slower growth rates. Much slower. And these are pigs from the same litters farrowed on my farm. The gilt/grower below is a 7 month old gilt next to an almost 2 year old sow. The sow is in excess of 300lbs. I have shown this picture to customers who have both gilts and barrows from the exact same litter.Both commented how much bigger this pig is than theirs.The common denominator. High fiber feeds like alfalfa cubes, hay and brewers grains etc. at their farms. None for growers at my farm. You should evaluate the crude fiber content of all your supplemental feed sources. Single stomach omnivores do not have the digestive capability of a ruminant or herbivore.Feed too much fiber to omnivores like chickens and they stop laying. Even a herbivore like a goose that feasts on grass cant live on hay.
Understand higher fiber content and free food arent excluded from my farm. I use brewers grains as a component in a total feed program to feed my boars on a maintenance diet. I find that it doesnt allow them to get too fat and they do their “job” better at those levels of condition. I will also give it (in small quantities) to sows on a maintenance diet.But I take them off of it well prior to breeding. But in growing pigs ,gestating sows, and lactating sows I want maximum nutrient and vitamin absorption. In those cases my Meishans only get what they can scrounge themselves(and they do eat excessive bedding,sticks etc).
Genetics: Each pure, genetically healthy, swine breed has a base range of growth based on its genetic capability.Decades of cross breeding in the commercial pig industry have produced meteoric growth rates as compared to older pure heritage breeds. However this has often come at a cost in pasturability ,tenderness ,fat amounts,fat quality and flavor in many cases. Its the “new white meat” and its here in a hurry. But with flavor and quality heritage meats (including pork) trending in the food world many small holder farmers look to the economic viability of heritage breeds including Meishan. But ,as much as the genetic capability, the genetic health of the individual animal can be a severely limiting factor. Excessive and undocumented inbreeding often results in inbreeding depression. Inbreeding depression in swine negatively impacts structure, litter sizes and severely impacts growth rate and maximum size. The A.M.B.A. is currently conducting a national herd survey including the investigation of breeding branches of undocumented pigs believed to be pure Meishan or Meishan influenced. And to date there are indications of some staggering instances of inbreeding in some of these pigs. Heavily inbred stock can limit the upside growth potential of any Meishan. It is why the A.M.B.A. requires a minimum level of pedigree history (verified by chain of custody) to have any animal considered for inclusion in the registry as foundation pure or grade on appearance. The value of the pedigree is not in helping you evaluate the pig you have.Your eyes are the best judge of that. What the pedigree does help you do is increase your chance of getting better piglets than their parent. Whether that is through out crossing bloodlines for greater genetic diversity or line breeding to lock traits.The best decision is an informed decision and that’s why the A.M.B.A. was formed.
Stocking Density and Pasture Quality . The final piece in the growth puzzle is stocking density and pasture quality and recovery. Quite simply pasture varies in nutrition.Both in the makeup of the grasses or legumes and even the time of year.How much nutrition is there when the pigs are.And how long does it take to recover from grazing?If you keep 60 pigs on 4 acres of pasture the consumption of nutrients takes place faster than its natural replacement. You must supplement to have a healthy herd. Without rotation nutrients are depleted and parasites explode. Parasites are a reality in pasture environments. It isnt a reflection on the breeder or animal. High stocking densities make parasite issues inevitable.This requires a realistic program of prevention and elimination. Hay isnt the quick fix for overgrazed or winter pastures many think it is (as explained above).In addition another homestead swine legend is the long term suitability of woodlots as a nutrition source for any group of pigs. Wood lots have limited resources which pigs,all pigs, strip quickly. And woodlots take months or years to recover.Oak trees don’t produce acorns 24/7/365.
So in conclusion. If growth rates are important in your farm model. you should mimic the feed and pasture protocols of people who are getting the growth rates you need to achieve. As a community of breeders committed to the preservation of this unique breed we are best served by an honest and open minded sharing of information.
I hope this was helpful and didn’t slay too many sacred cows.
President American Meishan Breeders Association.