Quantifying the effects of soil acidity on plant growth remains a challenging research topic as numerous soil and plant growth factors are influenced by pH and lime. In the field, annual ryegrass (Lolium multiflorum Lam. 'Marshall') responded positively to the application of 3.8 Mg lime/ha on a strongly acid (pH 4.7) Lilbert loamy fine sand (loamy, siliceous, thermic, arenic Plinthic Paleudult) over three growing seasons. Dry matter yield in some cuttings, however, was better correlated with soil Al, P, Ca, Mg, and K than with pH. A greenhouse study was undertaken to quantitatively determine the effects of these five minerals plus Mo on ryegrass yield in limed and unlimed Lilbert soil material. Three ryegrass cuttings were obtained from unlimed (pH 4.8) or limed (1000 mg CaCO3/kg) Lilbert soil which was also amended with five rates of Ca, K, Mg, Al, P, and Mo in combinations stipulated by central composite design methodology. Response surface models that fit yield to the applied treatments and soil test data were complex because all factors and many interactions were significant. Furthermore, the models were transformed as the plants matured and element availability changed due to mineral uptake. Most yield improvement derived from liming occurred as a result of the elimination of exchangeable Al with a concomitant increase in P efficiency. Applied Ca did not alleviate Al toxicity in unlimed soil. Chlorotic plants developed in all pots where Mg was excluded. Yield was increased by applied Mg and Mo in unlimed soil, but not in limed soil. Applied K improved yield only in limed soil. Although regression accounted for a large portion of the yield variability (R2 values ranged from 0.75 to 0.95), these models were unable to accurately predict yield in control treatments.

Leaf area and specific leaf area (SLA) are important parameters in many agronomic and ecological processes, but can be difficult and expensive to measure. This study was made to test simplified methods of estimating pearl millet [Pennisetum glaucum (L.) R. Br.] leaf area and SLA. Leaf length, maximum width, area, and dry mass data were obtained at 2-wk intervals from plants grown in 75-L pots. Pots contained 85 kg of acidic, P-deficient Betis sand (sandy, silicious, thermic Psammentic Paleustalf) and were treated with four P levels and two water treatments (stressed and nonstressed). Individual leaf area was estimated non-destructively with the following equations: Leaf area = 0.68 x (leaf length x maximum width) - 0.114 (R2 = 0.955) and Ln(leaf area) = 2.08 x Ln(length) - 3.53 (R2 = 0.939).Individual leaf area and whole plant leaf area were calculated from leaf dry mass by the following linear and nonlinear equations: Leaf area = 133.6 x Leaf mass + 22.69 (R2 = 0.900), and Leaf area = 162.84 x Leaf mass0.687 (R2 = 0.973).Residual errors indicated that the nonlinear equation was more accurate for area estimation of small leaves (less-than-or-equal-to 0.20 g), and that leaf area data were heteroscedastic. Leaf dry mass was also used to calculate SLA by the nonlinear equation SLA = 176.7 x Leaf mass-0.216 (R2 = 0.918), which gave excellent fit to experimental data independent of harvest date, P level and watering treatment. Our results demonstrate that pearl millet leaf area and SLA can be accurately estimated and easily simulated from simple regression equations.

Forty lactating Holstein cows in early to midlactation were used in a randomized complete block design to measure the effects of the following diets on milk casein. Treatments were four complete rations fed for ad libitum intake consisting of 1) 60% concentrate, 10% alfalfa hay, and 30% corn silage; 2) 45% concentrate, 10% alfalfa hay, 30% corn silage, and 15% whole cottonseed; 3) 60% concentrate, 5% alfalfa hay, 20% corn silage, and 15% whole cottonseed; and 4) 45% concentrate, 10% alfalfa hay, 30% corn silage, and 15% rice bran. Least squares means for daily DM intake all were significantly different and were 3.51, 3.90, 3.28, and 3.74% BW, respectively. Cows fed diet 3 had higher arterial glucose and insulin and venous insulin. Least squares means were significantly different for milk yield, 30.1, 31.4, 28.4, and 31.6 kg/d; for milk protein, 3.30, 3.13, 3.48, and 3.12%; and for casein N, .376, .358, 3.73, and .330, respectively. However, milk protein and casein N yields were similar for all cows. The diet that contained the highest percentage of starch did not result in a significantly higher percentage of casein N in the milk but had the lowest milk production. Both whole cottonseed and rice bran, substituted for concentrate, depressed milk protein percentage.

ABSTRACTEffects of ham size, aging time and temperature on the physicochemical composition of trichina‐infected dry‐cured hams were studied. Five muscle groups from small, medium and large short‐cure hams and large bag‐cure hams were analyzed for aw, moisture, NaCl and brine concentration. Semimembranosus/Adductor and Rectus femoris groups from the center had the lowest aw and moisture, and highest NaCl and brine concentrations compared to Biceps femoris + bottom Gastrocnemius groups from the hock. Aging at 32.2°C resulted in higher moisture and lower NaCl and brine percentages. Bag‐cured hams were similar to the short‐cure hams at 23.9°C. These results provide a detailed dataset of physicochemical analyses for dry‐cured hams by individual muscle groups under minimal curing conditions.

In Experiment 1, 24 cows were used to compare the acceptance of concentrate mixtures containing 1) no buffer, 2) 1.5% sodium bicarbonate, or 3) 1.5% Alkaten (a naturally occurring mineral containing primarily sodium carbonate and sodium bicarbonate). During the 1st wk the cows fed Alkaten had sharply reduced concentrate intakes. By the 3rd wk, concentrate intakes were nearly equal among groups. Total feed consumption was equal by the 2nd wk because cows compensated by eating more forage.

In Experiment 1, 27 lactating cows were fed complete rations ad libitum of 0, 15, and 30% whole cottonseed to examine the effects on intake, digestibility, blood gases, and blood metabolites. Dry matter intake declined linearly with increased cottonseed, but because of greater energy density, calculated net energy for lactation intake was not depressed significantly. Ether extract, crude protein, and calcium digestibility increased with cottonseed in the diet. Respiration rates declined with dry matter intake and increased cottonseed feeding; some blood gases were influenced by cottonseed feeding but not in a detrimental way. No data among 13 blood metabolites indicated effects of gossypol toxicity with 30% whole cottonseed in the diet. In Experiment 2, 24 dry, nonpregnant Holstein cows were offered complete rations ad libitum of 15, 35, and 55% whole cottonseed to measure responses in intake, respiration rates, and blood metabolites. The highest cottonseed diet significantly depressed intake of both dry matter and calculated net energy for lactation. Maximum dry matter from cottonseed eaten by an individual was 8.4 kg/d (average for 1 wk). Respiration rates declined parallel to intake. No evidence for gossypol toxicity was seen among data of 11 metabolites in blood.

Effects of rolling whole linted cottonseed and whole acid-delinted cottonseed on whole seed passage and digestibility were determined using 24 lactating Holstein cows. Whole seed passage averaged .74% in all cows fed whole linted seed during the standardization period and .45% in 6 cows fed whole linted seed during a comparison period, contrasted to 11.3% in 6 cows fed acid-delinted seed. Digestibility of ether extract was less in the 6 cows fed whole acid-delinted cottonseed. No advantage was for rolling whole linted cottonseed before feeding, but rolling was beneficial for whole acid-delinted cottonseed.

Left-truncated line transect data sets may occur when surveying with certain types of aircraft where the observer cannot look straight down. A general model of left-truncation in line transect sampling is developed and parametric estimators are derived in such cases when the underlying distribution of right-angle distances is either exponentially or half-normally distributed. Computer simulations demonstrate the validity of the derived estimators and the expected nonrobustness against alternative distributions. An aerial survey example using dolphin data is presented.

Twenty-four lactating cows were assigned randomly to three treatments to evaluate responses to large differences of dietary sodium and chloride. Treatments were corn-cottonseed meal-corn silage based complete rations with either: 1) .23% sodium chloride (control), 2) control plus 2.28% calcium chloride, or 3) control plus 1.70% sodium bicarbonate. Treatment effects were significant for urine pH (7.96, 5.41, 8.18), blood pH (7.50, 7.39, 7.49), partial pressure of oxygen (91.2, 99.4, 86.3 mm Hg), partial pressure of carbon dioxide (34.60, 30.57, 32.98 mm Hg), bicarbonate (26.20, 18.06, 24.64 meq/liter), total carbon dioxide (27.51, 19.18, 25.88 mM/liter), base excess (4.50, -4.31, 3.13 meq/liter), plasma chloride (93.4, 102.8, 95.7 meq/liter), serum potassium (3.26, 4.24, 4.14 meq/liter), and inorganic phosphorus (7.11, 5.61, 6.80 mg/100 ml). Blood glucose (45.1, 43.0, 55.5 mg/dl) and blood urea nitrogen (11.8, 8.7, 11.9 mg/dl) exhibited treatment effects. Respiration rates, 84.8, 61.8, 89.9 per min, and body temperatures, 39.7, 39.0, and 40.0 degrees C were significantly different. Lower intake of the high chloride diet and higher intake of the bicarbonate diet were probably responsible for some of the effects. Dietary electrolytes should receive attention in formulation because acid-base status of the animal is determined, in part, by ionic concentration and balance of the diet.

Burnham and Anderson (1976, Biometrics 32, 325-336) developed the basis for a distribution-free estimator of population density from line transect data. Without committing themselves to a specific algorithm, they recommended fitting a smooth curve h(*) to the midpoints of a frequency distribution of right-angle sighting distances, then using h(O) to estimate density. In this communication we propose a specific algorithm for fitting a polynomial of degree m to the midpoints of a frequency histogram by minimizing the sum of squared differences between the observed areas of each bar in a histogram and the corresponding integrated area under the curve. It is demonstrated by means of computer simulation that such a procedure can lead to small biases if the degree of the polynomial is not sufiicient to estimate the true underlying distribution when it ts Negative Exponential, Half-Normal or Triangular. Furthermore, the simulated standard error of the estimate is nearly proportional to the degree of the fitted polynomial. The authors recommend the compromise of a fourth-degree polynomial for which the bias is acceptably small and the coefficient of variation is approximately one percent in samples of right-angle sightings.

AbstractNew statistical methods of separating means into different groups should be brought to the attention of researchers so they can decide if the new methods can be used advantageously in their research programs. Our objective was to illustrate the use of a cluster analysis method (which we have called the Scott‐Knott method after the developers) and compare it to the commonly used Duncan's multiple range test. We applied the two methods to four sets of data. The results showed that the smaller the variance of the treatment means, the more similar were the separation groupings produced by the respective methods. However, in contrast to Duncart's procedure, the Scott‐Knott method never produced overlapping mean separation groups and distinct groups of non‐overlapping means are often desired by the researcher. The Scott‐Knott method has more complex calculations than Duncan's method, but it is readily programmable for computers and many desk top electronic calculators.

SUMMARY A new estimator is proposed for estimating ruffed grouse population densities by the line transect method of sampling. The estimator, utilizing only the right angle distances from the observer to the sighted animal, is shown to be approximately unbiased and an approximate variance of the estimator is provided in explicit form. Both the estimator and its variance are dependent on specified assumptions. The expected length of line transect necessary to sample exactly n' animals is derived and, in 2-stage sampling, the additional miles of transect necessary to achieve a predetermined precision. The authors examine data for the years 1950-58 taken at Cloquet, Minnesota, on the ruffed grouse (Bonasa umbellus) and compare densities calculated from the new estimator with the estimated densities of the previously published Hayne, King, and Webb estimators for the line transect method. The underlying assumptions are discussed and several are tested on these as well as more extensive data.

Within herd variation in composition among biweekly samples of milk during one year was determined by summarizing the data obtained from 88 herds representing the 2,536 herds supplying the Twin City Milk Producers Association. Arithmetic averages of the 88 Standard deviations and ranges in herd standard deviations by constituents follow: fat (average—0.224%, range—0.086-0.528%); solids-not-fat (average—0.147%, range—0.058-0.340); protein (average—0.181%, range—0.062-0.323%); casein (average—0.167%, range—0.056-0.290%). Haulers obtained samples from each farm herd in a routine way and the analytical work was routine. Thus, the variations reported include herd factors, influence of sampling, and analytical variations.

Heredity and environment interactions were studied in regard to carcass characteristics by subjecting three kinds of crossbred pigs to three feeding treatments in a factorial experiment. The experiment was conducted in two replications with a total of 180 pigs, 10 in each of 18 pens. The crossbred pigs were sired by Minnesota No. 2, Minnesota No. 3 and Minnesota No. 2A boars and out of Minnesota No. 1 dams. The treatments were full-feeding, 85% restricted feeding, and the self-feeding of a feed mixture containing 20% grass and alfalfa meal and 80% concentrates. The traits studied were live weight before slaughter, carcass weight, carcass length, backfat thickness, ham weight, five prima l cuts, loin-eye area, estimated percent of lean, fat, and bone. Significant breeding × treatment interactions were found in ham weight, loin-eye area and carcass length. All treatment mean squares were significant except those for loin-eye area, loin weight and ham weight. Breeding group mean squares differed significantly for backfat thickness, loin-eye area, percent lean, percent fat, percent bone, carcass length, and ham weight. The breeding group mean squares also were significant for carcass weight, the five primal cuts, picnics, butts and loins, but were not significant for bellies and live weight before slaughter. The significant B × T interaction mean squares for ham weight, loin-eye area, and carcass length indicate that the three kinds of crosses responded differentially to the feeding treatments employed in this trial.

The experiments with suckling lambs were conducted to determine the effect of grain feeding the ewe and/or creep feeding the lambs on lamb gains. Both creep feeding the lambs and grain feeding the lactating ewes increased lamb gains significantly. The treatments ranked in descending order with respect to weight gains as follows: (1) the combination of grain feeding of the ewes and creep feeding of the lambs; (2) no grain feeding plus creep feeding; (3) grain feeding and no creep feeding; (4) no grain feeding and no creep feeding. A complete pelleted creep feed fed in Experiment 2 resulted in significantly faster gains than a grain-long hay creep feed fed in Experiment 1.

SynopsisOf 332 farm silos studied in detail, 42% showed the presence of nitrogen dioxide in concentrations considered hazardous. The factors of organic matter, available potassium and phosphorus levels in soils, and the use of sodium metabisulfite as a silage preservative were related to production of nitrogen dioxide.