THE DIGESTIBILITY BY PIGS OF DRY MATTER, ENERGY, PROTEIN AND AMINO ACIDS IN WHEAT CULTIVARS. II. FIFTEEN CULTIVARS GROWN IN TWO YEARS, COMPARED WITH BONANZA AND FERGUS BARLEYS, AND 3CW-GRADE HARD RED SPRING WHEAT

Abstract

Fifteen wheat cultivars (Triticum vulgare L.) and two barley cultivars (Hordeum vulgare L.), some grown in two or three different years, were evaluated in two digestion trials with pigs of 40 kg initial weight. Some samples had frost damage. Each cultivar was measured for bulk weight (kg/hL), weight in g/1000 kernels, kernel plumpness and percent germination. The grains and feces were analyzed for gross energy, crude protein and amino acids. The diets comprised 95.7% ground grain, 0.5% chromic oxide, and mineral and vitamin supplements. Crude protein (N × 6.25) ranged from 11.1 to 19.7%. In terms of digestibility of energy, digestibility of protein, content of digestible crude protein (DCP), available lysine and digestible energy (DE), the wheat cultivars Inia-66 and Neepawa ranked highest, followed by Norquay, then Glenlea, Pitic-62 and PFW606A. Within cultivar, year-to-year differences were observed as well as some effects of frost damage. Cultivar differences in DE were found but DCP and available lysine were identified as the most important nutritional criteria for wheat to be used as the major grain in the animal diet. Environmental conditions affecting crop growth and seed maturity may be as important as genetic differences between cultivars in regard to nutritional quality evaluations as measured in these trials.Key words: Digestibility, wheat, protein, energy, amino acids, pigs