By Joel DeRouchey, Mike Tokach, Jason Woodworth, Bob Goodband, Jordan Gebhardt and Katelyn Gaffield of Kansas State University
A common question we hear each May is, “What we can do for summer marketed pigs nutritionally to increase or maintain market weight?” Although it’s a valid question, it needs to be asked in the beginning of the year. It is all about backward math on days to market and what can be achieved economically.
Do We Need to Change Diets in the Nursery?
Nutritionally, very little can be changed during the first three to four weeks postweaning. These diets are designed to allow pigs to get off to the best start possible.
For 24 to 42 days postweaning, pigs will respond to increased diet energy and growth promoters such as added copper, in-feed acids, and other additives that have been shown to be fairly consistent in a growth response during this pig age. However, due to the short nature of this period, this often results in very small differences of 0.5 lb. to, at the most, 1.5 lb. However, these practices are done on a routine basis regardless of season.
Grow-Finish Adjustments
The implementation of summer or winter diet programs are more common in grow-finish due to the magnitude of change possible. Each year, the situation of what economically can be done for a summer nutrition program is different. However, the most common concept of increased diet energy is by the reduction or removal of lower energy ingredients such as distiller’s dried grains with solubles (DDGS) and wheat middlings. Also, in areas of DDGS vomitoxin concerns, this practice directly lowers diet levels which can improve growth. As we replace low energy ingredients with more corn and soybean meal, the diet energy increases.
Historically, added fat has been a practice to increase diet energy, but fat price the past several years has been higher than benefit provided. While fat is much lower in cost than last year, at roughly 40¢ to 45¢ per pound, its economics to improve both feed:gain and carcass weight is still too high to justify its use right now. But this is a consideration to monitor as feed and market prices change.
Feed additives such as copper, an ionophore, acidifiers, direct fed microbials, essential oils, L-carnitine or multienzyme blends can improve gain or feed efficiency. However, when a response is present, it is often a 1% to 2% increase, and the response might not be additive when using multiple additives.
Summer Diet Implementation
Consider a 120-day finishing feeding period, pigs marketed on June 1 or later can start on summer strategy diets after Feb. 1. The key is keeping all finishing pigs marketed before the summer marketing period on the non-summer diet program. Just as important to save on feed costs, newly placed finishing pigs in mid-June and after should be fed to non-summer diets as they are marketed in October and later.
