Consecutive Lots Research Articles

Three-generation reproduction and dominant lethal mutagenesis studies of ethylene glycol in the rat

To assess the possible effects of ethylene glycol (EG) on reproductive performance and mutagenesis, three-generation reproduction and dominant lethal mutagenesis studies were performed in the Fischer 344 rat. EG was included in the diet at approximate dosages of 1.0, 0.2, and 0.04 g/kg/day during three generations of reproduction. Each generation was bred once. In a dominant lethal mutagenesis study, the F2 males from the reproduction study were bred to three consecutive lots of untreated females at weekly intervals. Concomitantly, another group of untreated F2 males that received a single ip injection of 0.50 mg/kg triethylenemelamine (TEM) were bred similarly to serve as a positive control group. No evidence of reduced fertility or increased fetal death was observed in any of the groups receiving EG. Dominant lethal effects in the TEM group confirmed the susceptibility of the rats to a known mutagen. In conclusion, there were no reproductive or dominant lethal effects associated with the inclusion of as much as 1.0 g/kg/day of EG in the diet.

Three-Generation Reproduction and Dominant Lethal Mutagenesis Studies of Ethylene Glycol in the Rat

Three-Generation Reproduction and Dominant Lethal Mutagenesis Studies of Ethylene Glycol in the Rat. DEPASS, L.R., WOODSIDE, M.D., MARONPOT, R.R., AND WEIL, C.S. (1986). Fundam. Appl Toxicol. 7, 566-572. To assess the possible effects of ethylene glycol (EG) on reproductive performance and mutagenesis, three-generation reproduction and dominant lethal mutagenesis studies were performed in the Fischer 344 rat. EG was included in the diet at approximate dosages of 1.0, 0.2, and 0.04 g/kg/day during three generations of reproduction. Each generation was bred once. In a dominant lethal mutagenesis study, the F2 males from the reproduction study were bred to three consecutive lots of untreated females at weekly intervals. Concomitantly, another group of untreated F2 males that received a single ip injection of 0.50 mg/kg triethylenemelamine (TEM) were bred similarly to serve as a positive control group. No evidence of reduced fertility or increased fetal death was observed in any of the groups receiving EG. Dominant lethal effects in the TEM group confirmed the susceptibility of the rats to a known mutagen. In conclusion, there were no reproductive or dominant lethal effects associated with the inclusion of as much as 1.0 g/kg/day of EG in the diet.

Suspension Systems for Small Sample Inspections

In this paper rules are discussed for suspending inspection on the basis of unfavorable lot history, when small sample sampling plans are specified. The decision to suspend, which is based on cumulative lot dispositions over k consecutive lots, occurs if j lots are rejected. The expected time to suspension is given for j = 2 and j = 3. The user is offered the choice of employing a designed plan of suspension systems based on MIL-STD-105D or designing a specific system using the notion of a reference quality level. Several methods of choosing a suspension system are discussed.

Utilization of Swine Manure in a Polyculture of Asian and North American Fishes

Chinese methods of fish culture were evaluated for potential use in animal waste management, pollution control, and the production of protein. Two ponds were stocked with grass carp (Ctenopharyngodon idella), silver carp (Hypophthalmichthys molotrix), bighead carp (Aristichthys nobilis), carp (Cyprinus carpio), northern largemouth bass (Micropterus salmoides salmoides), channel catfish (Ictalurus punctatus), and the hybrid of bigmouth buffalo female (Ictiobus cyprinellus) and black buffalo male (I. niger). One pond (0.127 hectare) received the total wastes from five growing pigs (about 39 pigs/hectare of water area), the other pond (0.121 hectare) received the wastes from eight pigs (66 pigs/hectare). Two consecutive lots of pigs were fattened during the study. Over a fish-growing period of about 170 days (May to October 1975) the net increments in fish biomass were 2,971 kg/hectare in the 0.127-hectare pond and 3,834 kg/hectare in the 0.121-hectare pond. A beneficial influence by the fish on water quality was indicated by continuously adequate levels of dissolved oxygen, and final biochemical oxygen demands in the range of 8-12 mg/liter.

A cost analysis of sampling inspection under Military Standard 105D

AbstractMilitary Standard 105D has been almost universally adopted by government and private consumers for the lot‐by‐lot sampling inspection of product which may be inspected on a dichotomoun basisThe plan specifies, for each lot size, a random sample size and set of acceptance numbers (maximum allowable number of defectives in each sample). The acceptance numbers are based upon the binomial distribution and depend upon the quality required by the purchaser. Where several consecutive lots are submitted, a shift to less severe (“reduced”) inspection or more severe (“tightened”) inspection is specified when the ongoing quality is very high or low. Further experience permits a return to normal sampling from either of these statesThis paper examines the long range costs of such a sampling scheme. The three inspection types are considered as three distinct Markov chains, with periodic transitions from chain to chain. The expected sample size and the expected proportion of rejected product are determined as a function of the two parameters under control of the manufacturer, lot size and product quality. Some numerical examples are given which illustrate how to compute the overall cost of sampling inspection. Suggestions are made concerning the choice of parameters to minimize this cost.

PERSISTENCE OF ANTIBODY AFTER ORAL TRIVALENT POLIOVIRUS VACCINE (SABIN STRAINS).

BECAUSE of the favorable rates of serum-antibody conversion obtained in a pilot study in Elkins, West Virginia, with two feedings of a trivalent oral poliovirus vaccine,1 the same vaccine was used in a mass vaccination program in Hillsborough County, Florida, in the early spring of 1962.2 In the Hillsborough County program 5 different lots of the trivalent vaccine were used. They represented mixtures of 5 consecutive lots of monovalent vaccine of each poliovirus type prepared from the Sabin vaccine strains by Lederle Laboratories in compliance with vaccine-licensing requirements.3 All 15 monovalent lots had passed all the prescribed tests, including . . .

DEVELOPMENT OF PERTUSSIS VACCINE PRODUCTION AND CONTROL IN THE NATIONAL INSTITUTE OF PUBLIC HEALTH IN THE NETHERLANDS DURING THE YEARS 1950--1962.

The development of the pertussis vaccine production in the National Institute of Public Health in the Netherlands since 1953, and the results with the consecutive lots of vaccine in the mouse protection test and the U.S.A. toxicity test are described. The results in the latter test are compared with the results of a locally developed guinea pig toxicity test. Special attention is given to the difficulties encountered when the U.S.A. toxicity test is used for adsorbed DPT vaccines. The potency data of all lots of DPT vaccines produced since 1958 fall within the limits of the potency test as prescribed in the U.S.A. Minimum Requirements. There are indications that the increased potency of the vaccine may have led to a lower mortality rate of pertussis.

Cumulative testing experience with consecutive lots of oral poliomyelitis vaccine.

Cumulative testing experience with consecutive lots of oral poliomyelitis vaccine.