Relative Vitamin K Potency of Two Water-Soluble Menadione Analogues

Dietary Vitamin K1 Requirement and Comparison of Biopotency of Different Vitamin K Sources for Young Turkeys

In a preliminary experiment, the inclusion of vitamin K1 (K1) at a dietary level of 0.1 mg/kg was as effective as 1 or 2 mg/kg in reducing plasma prothrombin time (PT). To obtain an estimate of the dietary K1 requirement and to compare the biopotency of different vitamin K sources for poults, three additional experiments were conducted. In Experiment 1, an incomplete factorial arrangement of treatments was used in which five dietary concentrations of K1 (0, 0.1, 0.25, 0.5, or 2.0 mg/kg) were tested and two concentrations of neomycin (0 or 75 mg/L) in drinking water were used in conjunction with 0, 0.1, and 0.5 mg of K1/kg of diet. Thus, we used a total of eight treatments. Each treatment was given to two pens of poults, with eight poults per pen. Prothrombin time and prothrombin concentration (PC) in plasma were not influenced by inclusion of neomycin in drinking water. The K1 requirement was estimated, on the basis of PT and PC, to be 0.099 and 0.13 mg/kg, respectively, in Experiment 1. Dietary K1 concentrations tested in Experiment 2 were 0, 0.08, 0.31, or 0.44 mg/kg. A similar protocol to that of Experiment 1 was used in this experiment. The results of Experiment 2 indicated that the dietary K1 requirement was 0.079 mg, based on the influence of dietary K1 on PT. In Experiment 3, dietary treatments consisted of the equivalent of 0.22, 0.55, or 1.11 microM of menadione equivalent/kg from vitamin K1, menadione dimethypyrimidinol bisulfite (MPB) or menadione nicotinamide bisulfite (MNB), respectively, and a control without supplementation of any vitamin K source. The results of Experiment 3 showed that the biopotency of K1 was greater than that of MPB or MNB. The biopotencies of MPB and MNB were similar, although MNB was more potent in reducing plasma PT when supplemented at the level of 0.1 mg of menadione/kg. A nadir of PT and a plateau of PC were evident with a dietary supplementation of MPB or MNB at a level of 0.25 mg of menadione/kg. Results of this research show that the dietary K1 requirement of young turkeys is in the range of 0.079 to 0.13 mg/kg, and ingestion of neomycin did not affect estimates of the requirement. The biopotency of vitamin K1 in reducing plasma PT and increasing plasma PC was greater than that of MPB or MNB. The biopotency of MNB was greater than that of MPB when menadione supplementation was equivalent to 0.10 mg of K1/kg.

Temperature and vitamin requirements of the domestic fowl

The basic vitamin requirements of the bird must be more clearly established before the true effects of temperature can accurately be measured. Although the literature reveals progress, the knowledge gained (as in many other fields of scientific investigation) is spotty, contradictory, vague, and intriguing, providing a basis for further planned comprehensive investigation. A review of literature leads to some general conclusions on the effects of temperature on vitamin requirements. 1) Feed consumption regulates vitamin intake, and feed consumption is closely moderated by environmental temperature, both high or low and to a varied extent. 2) Factors involved in management, growth, egg production, light, etc. are very influential interactions. 3) High environmental temperature and subsequent heat stress will result in altered availability and utilization of specific nutrients. 4) There are factors regulating nutrient intake that relate to utilization, such as energy-protein ratio, management, age of bird, and genetic composition of the bird. 5) Care and treatment of feed, age, storage conditions, pelleting, and characteristics of the ingredients are important influences.

Effect of pelleting on the vitamin K activity of various vitamin K3 preparations in chicks

A study with chicks was conducted to compare the relative vitamin K3 stability of various menadione preparations in mash and pellets. The preparations assayed were menadione sodium bisulfite, menadione sodium bisulfite complex, menadione dimethylpyrimidinol bisulfite and Kastab (a physically stabilized preparation of menadione sodium bisulfite). Pelleting increased the stability of all preparations when measured by the partial thromboplastin assay. The general trend in stability obtained by both procedures was in decreasing order: Kastab, menadione dimethylpyrimidinol bisulfite, menadione bisulfite complex and menadione bisulfite. Stability, determined chemically in vitamin microelement premixes, gave similar results.