Apparent digestibility of nitrogen and amino acids in protein feedstuffs by growing pigs.

Eight digestion trials were conducted with pigs fitted with ileal T-cannulas to determine the apparent digestibilities of N and amino acids in common protein feedstuffs. Trial-to-trial variation was minimal as determined by the variation in digestibilities for soybean meal, which was evaluated in each trial. Apparent digestibilities varied widely; ileal N digestibility ranged from 88 to 63%, and ileal lysine digestibility ranged from 93 to 40%. In general, ring-dried blood meal, corn gluten meal, Menhaden fish meal, poultry-by-product meal and extruded whole soybeans were the most digestible, followed by canola meal, sunflower meal, peanut meal and meat and bone meal. Cottonseed meal and feather meal were the least digestible. Mean values for each feedstuff agree well with published data. Variation in digestibilities among samples of the same feedstuff was greater for the meat and bone meals. Regression of ileal essential amino acid digestibilities on ileal and fecal N digestibility indicated that amino acid digestibilities can be predicted more precisely from ileal N digestibility than from fecal N digestibility. However, neither ileal nor fecal N digestibility could be used with a high degree of certainty to predict ileal amino acid digestibilities.

Analytical evaluation of urinary excretion of furosemide in barrows.

Market weight barrows were dosed with furosemide IM or orally, and urine (5 barrows) and blood (1 barrow) samples were collected. Extraction procedures and high-performance liquid chromatographic conditions were modified and adapted for analysis of porcine samples. Furosemide was cleared rapidly from plasma, but could be detected in urine 4 to 5 days after administration, using fluorescent or ultraviolet detection. Fluorescent detection was the preferred method for screening for furosemide. Approximately 12% of furosemide was excreted as the glucuronide conjugate.