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Seismic stratigraphic analysis of a grid of 7860 km of shallow seismic Sleevegun data, plus lithological and biostratigraphic (foraminifera) data interpreted from core and sea-bed samples have been integrated into a detailed geological model for the Upper Cretaceous succession of the proximal Orange Basin. Emphasis has been placed on the palaeoenvironmental interpretation of incised valley fill sequences of this succession. Seismic reflection geometries for the Middle Albian to Lower Cenomanian interval show that the entire coast was dominated by aggradational fluvial braid-plain facies. The Lower Turonian to Upper Coniacian succession marks the appearance of repeated major incision into the exposed coastal plain by large fluvial drainage networks. This succession is characterized by fourth-order, fluvial-to-marine sequences, with valley incision up to 25 km wide and 70 m deep. Detailed palaeoenvironmental analysis indicates periodically waterlogged, highly reducing fluvial floodplain environments with valley systems that were flooded to create wave-dominated estuaries. Major fluvial activity during the Turonian was in an area that lies offshore of the present-day Swartlintjies to Groen River mouths in the southern part of the Orange Basin. During the Coniacian the site of fluvial activity changed to the central Orange Basin, offshore of the present-day Buffels River. These observations contradict previously published views that a dominant Orange River drainage system existed since the Albian, at a position coincident with the present-day mouth. [ABSTRACT FROM AUTHOR]

It is usually the desire of the researcher to demonstrate a difference in the comparisons made. This is certainly the case when an improved product is desired. However, in establishing the bioequivalence of a test product to a standard, the objective is usually to conclude, with reasonable justification, that no difference has been detected. In making such determinations, the probabilities of accepting false hypotheses or those of rejecting correct hypotheses of difference must be taken into account. Before beginning the trial, the researcher should have a good estimate of the power that will be associated with the detection of a given minimum acceptable difference. The required sample size for achieving the desired power for these tests depends on the coefficient of variation in the data collected and the minimum detectable difference between two groups that the study is meant to detect. It is important to determine the relative magnitudes of the sampling and the experimental errors in order to decide, for a given number of animals available for the study, how they might be best subdivided into groups within treatment. This paper addresses these points and others in an attempt to summarize some of the key items that researchers should consider when planning trials for the bioequivalence testing of new products.

Sow and feeder pig productivity was measured in a representative sample of herds producing more than 1,000 pigs/yr in Ontario, Canada. Correlations between the various indicators of productivity were determined. There was a wide range between farms in sow productivity, in grower-finisher pig efficiency and in the efficiency of resource utilization. Larger herds made better use of available physical resources, as indicated by the greater number of pigs weaned per farrowing crate per year and the greater number of feeder pigs marketed per m2of feeder pen space per year. They also tended to have greater biological efficiency, as indicated by the greater number of pigs weaned per sow per year. Interrelationships among productivity variables were discussed. It was concluded that the potential for improvement of productivity in Canadian swine herds was great.

The effects of initial weight (IW) and of dietary protein level (21, 23, 25, 27, 29 and 31%) on the performance of piglets weaned at 7 d were studied in two trials. Each trial involved 48 Yorkshire piglets and was divided into three 5-d periods. Increases in the crude protein (CP) content of the diet caused linear (P<.05) increases in average daily gains (ADG) and in gains adjusted to equal feed intake by covariance (AADG), but had no effect on average daily feed consumption (ADF). Initially heavier pigs ate more feed (P<.05) and gained more weight (P<.05) than those that were initially lighter in weight. However, more efficient (P<.05) gains due to a higher IW were observed only in period 2. Surface response techniques were used to study the relationships among ADG, IW and CP. The equation ADG = 4.3 × IW × CP−.018 × IW2× CP2−6.5 described these relationships satisfactorily (r2= .52; SE = 29.9; P<.01). According to this equation, ADG increased with increases in IW or CP but only up to a certain level beyond which the gains became smaller. At each IW there was a CP content at which gains would become maximal and vice versa. The combination of IW and CP at which maximum gains would be obtained, however, was outside the range of values investigated. Increases in dietary protein level caused linear increases in plasma urea N concentration (P<.01) and in CP digestibility (P<.05).

One hundred and five rats and 48 Yorkshire pigs were used in a series of trials to determine the protein quality in wheat shorts. Supplementation of wheat shorts with the five calculated limiting amino acids followed by individual omission of each of these added amino acids indicated that threonine was first limiting and lysine and methionine second limiting for the rat.Supplementation of lysine and/or threonine for the pig showed equal limitation of these amino acids with respect to growth performance and fasting plasma urea nitrogen (PUN). However, post-prandial PUN, nitrogen balance and urine urea measurements all indicated that lysine was first limiting and threonine second limiting for swine.The protein in shorts showed an apparent digestibility of only 75% in swine.

Supplementation of wheat shorts with varied levels of corn and two levels of soybean meal indicated a major limitation of protein quality with respect to the requirements of growing and finishing swine. The apparent digestibility of protein of wheat shorts was 70 to 75%; the digestible energy was found to be less than 3.0 kcal/g. A separate batch of wheat shorts was found to have an apparent nitrogen digestibility of 80% and an energy level of 3.44 kcal/g.Rate of growth and carcass quality were not affected by the replacement of a corn-soybean meal diet with graded levels of wheat shorts. A linear reduction in dressing percentage and feed efficiency was observed.Pelleting improved the digestibility of energy of wheat shorts but elicited no effect on nitrogen or phosphorus. Regrinding tended to improve energy and nitrogen availability. Auto-claving and extrusion depressed phosphorus retention. Pelleting and extrusion offered the added benefit of reduced storage cost due to increased density.

Administration of 1 ml of donor whole blood 7 d before renal transplantation produces long-term (greater than 100 d) graft survival in the DA (RT1a) into PVG (RT1c) rat strain combination. Using this model, the pattern and phenotype of infiltrating leukocytes were examined in rejecting and enhanced renal allografts, at days 1, 3, 5, and 7 after transplantation, by immunohistologic techniques. Paradoxically, enhanced grafts showed a more rapid and substantial leukocyte infiltrate, the phenotype of which was similar to that in rejecting grafts except for a reduced number of MRC OX-8+ cells and MRC OX-39+ cells. Graft infiltrating cells and splenocytes from transfused animals showed similar, although modest, levels of both nonspecific cytotoxicity and alloantigen-specific cytotoxicity. Immunohistologic analysis of MHC antigen distribution within the allograft revealed, unexpectedly, that enhanced grafts underwent an accelerated and extensive induction of both donor class I and class II MHC antigens. These findings were confirmed by allospecific quantitative absorption analysis, which showed severalfold increases in class I and class II MHC antigens by day 3 in enhanced grafts but not until day 5 in rejecting grafts. An additional observation was the more rapid disappearance of donor interstitial cells from enhanced grafts. These findings emphasize the overwhelming suppressive effect induced by an organ allograft after preoperative blood transfusion despite the associated induction of large numbers of potential effector cells and increased target antigen density within the graft.

The period of time after administration over which blood level measurements are required to obtain a reliable bioavailability comparison of two or more formulations of the same drug was considered by the analysis of bioavailability data taken from the literature. The drugs examined, selected to represent a range of absorption and elimination half‐lives, were acetaminophen, aminosalicylic acid, chloramphenicol, chlordiazepoxide, digoxin, isoniazid, phenylbutazone, sulfamethizole, tetracycline, and warfarin. For most drugs, ratios of areas under the curve changed little between the end of the absorption period and the time when blood sampling was terminated. Reliable bioavailability comparisons among different brands of the drugs apparently could have been made by blood sampling over 24hr or less.