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Histidine may be the sixth limiting amino acid (AA) in practical nursery diets supplemented with high amounts of feed-grade AA. Therefore, 2 experiments were conducted to determine the standardized ileal digestible (SID) His:Lys ratio requirement estimate for growth performance of 7- to 11-kg nursery pigs. A total of 360 and 350 pigs (DNA 241 × 600, Columbus, NE; initially 7.1 ± 0.31 and 6.6 ± 0.36 kg) were used in Exp. 1 and 2, respectively. There were 5 pigs per pen with 12 replicates per treatment in Exp. 1 and 10 replicates per treatment in Exp. 2. After weaning, pigs were fed a common pelleted diet for 10 d in Exp. 1 and 7 d in Exp. 2. Then, pens were assigned to treatments in a randomized complete block design with body weight (BW) as the blocking factor. Dietary treatments consisted of SID His:Lys ratios of 24%, 28%, 32%, 36%, 40%, and 44% in Exp. 1 and 24%, 28%, 30%, 32%, 34%, 36%, and 42% in Exp. 2. Experimental diets were fed in pellet form for 10 or 14 d in Exp. 1 and 2, followed by a common mash diet for 15 or 14 d, respectively. Data were analyzed using the GLIMMIX and NLMIXED procedures of SAS, fitting data with heterogeneous variance when needed. The competing statistical models utilized were quadratic polynomial, broken-line linear (BLL), and broken-line quadratic. In Exp. 1, increasing SID His:Lys ratio increased (quadratic, P = 0.001) ADG, ADFI, G:F, and day 10 BW. In Exp. 2, ADG, G:F, and day 14 BW increased (quadratic, P = 0.001), and ADFI increased linearly (P = 0.001) with increasing SID His:Lys ratio. The best-fitting model for all response variables analyzed was the BLL. In Exp. 1, requirement estimates were 29.7%, 29.1%, and 29.8% SID His:Lys ratio for ADG, ADFI, and G:F, respectively. In Exp. 2, the SID His:Lys ratio requirement estimates were 31.0% for ADG and 28.6% for G:F. These results suggest that the SID His requirement estimate for growth performance is no more than 31% of Lys and that the NRC (2012) SID His requirement of 34% of Lys may be overestimated for 7- to 11-kg pigs.

The objective was to determine the effect of forage quality on apparent total tract digestibility and ruminal fermentation in cattle versus sheep. Five yearling English crossbred (Hereford × Angus) steers (440.4 ± 35.6 kg of initial BW) and 5 yearling whiteface (Rambouillet × Columbia × Debouillet) wethers (44.4 ± 4.6 kg of initial BW), each fitted with a ruminal cannula, were randomly assigned to 1 of 3 forage sources within ruminant specie, and the study was conducted over 3 periods. For forage source, both animal and period served as the blocking factor with all forage sources represented once within each animal and all forage sources represented at least once within each period. The treatment structure was arranged in a 2 × 3 factorial with ruminant species (2) and forage source (3) as the factors. Forage sources were 1) alfalfa hay (Medicago sativa; 17.5% CP and 34.1% NDF, DM basis), 2) warm-season grass hay mix (Bothriochloa ischaemum and Cynodon dactylon; 7.3% CP and 74.7% NDF, DM basis), and 3) lovegrass hay (Eragrostis curvula; 2.5% CP and 81.9% NDF, DM basis). As a percent of BW, steers and wethers consumed similar (P ≤ 0.06) amounts of forage, and intake was more influenced by forage quality (P < 0.001) than ruminant species (P = 0.35). When expressed per unit of metabolic BW, cattle consumed more (P < 0.001) DM, NDF, and N than sheep. Apparent total tract digestibility was similar among steers and wethers when alfalfa or grass hay was fed, but decreased to a greater extent in wethers when low-quality lovegrass hay was fed (ruminant species × diet interaction, P ≤ 0.01). Rate (%/h) of ruminal NDF disappearance was greater (P = 0.02) for alfalfa and grass hay than lovegrass, but was not influenced (P = 0.12) by ruminant species. In addition, ruminal DM fill was influenced more (P < 0.01) by forage than by ruminant species (P = 0.07). Steers and wethers had greater (P < 0.01) DM fill from grass hay and lovegrass hay than alfalfa before and 5 h after feeding. Ruminal VFA were generally not influenced (P ≥ 0.06) by ruminant specie. Results suggest that apparent total tract digestibilities are more similar among ruminant species when moderate- to high-quality forages are evaluated. However, sheep are not an adequate model for cattle when low-quality forages are compared because cattle digest low-quality forages to a greater extent than sheep. Expressing digestibility as digestible intake per unit of BW allows for a wider range of forage qualities to be compared when substituting sheep for cattle.

The objective of this study was to determine the effect of time of rumen fluid collection relative to feeding on gas production kinetics for in vitro rumen fermentation. Three ruminally cannulated Holstein heifers were rumen fluid donors. Feed was removed from heifers 12 h prior to feeding, rumen fluid was collected from each heifer before feeding (0 h), and at 2, 4, and 6 h after feeding, repeated on three separate incubation days. Buffered rumen fluid (100 mL) was incubated in 250-mL bottles containing 1.4 g of dried TMR, in duplicate for each heifer at each collection time. All bottles were incubated for 24 h at 39°C and constant agitation (60 rpm), and capped with monitors to capture temperature and pressure every 15 min (RF1, Ankom Technology, Macedon, NY). At the end of incubation, final pH was recorded. Gas data were fit with nonlinear regression comparison of fit in GraphPad Prism 7 to find best fit regression. The formula with best fit was as follows: y = Vm(1 − (e(−Kd(x − lag)))), where y is gas produced at time X (mmol), Vm is the asymptotic gas production (mmol), Kd indicates the fractional rate of gas production (mmol/h), X is time (h), and lag refers to the lag time before the start of fermentation (h) as indicated by positive gas production (R2 = 0.98). Data were analyzed using PROC GLIMMIX of SAS, with donor as the experimental unit and day as the random blocking factor; significance is defined as P ≤ 0.05. Time of rumen fluid collection significantly affected gas production kinetics (lag P = 0.01, VmP = 0.03, KdP

In a breach-of-containment nuclear reactor accident, the near-field exposure is primarily through inhalation of radioiodine. Thyroid blockade by oral potassium iodide (KI) is a practical and effective protective measure for the general public in such an emergency. The retention functions incorporating the thyroid blocking effects by KI have been derived using a standard three-compartment model of iodine metabolism. This allows more accurate estimation of the thyroid dose by calculating the blocking factor.

Peripheral lymphocytes from healthy pregnant women secrete a mediator protein named the progesterone-induced blocking factor (PIBF) that exerts an immunomodulatory function and contributes to the maintenance of pregnancy in mice. The gene coding for PIBF mRNA has been cloned and sequenced, and now the recombinant human protein is available. The aim of this study was to develop an ELISA test for determining PIBF concentrations in biological samples of pregnant women. We determined urinary PIBF concentrations of 86 healthy nonpregnant individuals and from almost 500 pregnant women by ELISA. During normal pregnancy, the concentration of PIBF continuously increased until the 37th gestational week and was followed by a sharp decrease after the 41st week of gestation. In pathological pregnancies, urinary PIBF levels failed to increase. The onset of labor was predictable on the basis of this test, whether it was term or preterm delivery. In urine of patients with preeclampsia, PIBF concentrations were significantly lower than in normal pregnancy and showed a correlation with the number of symptoms presented. These data, in line with previous in vivo findings, suggest that PIBF production is a characteristic feature of normal pregnancy, and determination of PIBF concentration in urine might be of use for the diagnosis of threatened premature pregnancy termination.

A field test was conducted to evaluate the efficacy of five organically acceptable foliar insecticides for the control of GPA on young (non-bearing) peach trees under New Mexico conditions. The trial was conducted in Apr, 2013, in a 0.12 ha block of peaches (planted in Mar, 2012), at the Los Lunas Agricultural Science Center, Los Lunas, NM. The experiment was conducted as a randomized complete block design with five single-tree replicates per treatment, using initial (pre-treatment) infestation levels as the blocking factor. A water-treated check was included. Aphid populations on the experimental trees were assessed by counting all individuals on the two apical leaves of five randomly selected shoots per tree. Pre-treatment counts were made on 25 Apr, 2013 and all applications were made between 8 and 10:20 am the following day using a 7.5 liter garden sprayer. Products, formulations and rates are listed in Table 1. All treatments were applied to run-off. Aphid populations were re-assessed at 1, 3 and 7 DAT using the same method as described above. The data were not normally distributed and could not be successfully transformed; they were therefore analyzed by Kruskal-Wallis non-parametric analysis of variance, followed, where appropriate, by pairwise between-treatment comparison using the Mann-Whitney procedure. All statistical analyses were conducted using Minitab® statistical software.

Experiments having two treatment factors and one blocking factor are considered in which a particular combination of treatment factor levels must be excluded. The motivation for the work is a medical trial of two drugs in which a double placebo cannot be administered on ethical grounds. The contrasts of interest compare the effects of having both treatment factors at nonzero labelled levels with the effects of having only one treatment factor at a nonzero labelled level. A lower bound is derived on the average variance of the contrast estimators in n×m experiments

Summary Washed leukocytes from sarcoid patients were not found to be significantly hyporeactive to phytohaemagglutinin in the mixed leukocyte migration test. An immune blocking factor, however, was found in the sera of these patients which suppressed the reaction of normal subject's white cells to phytohaemagglutinin.

SUMMARY The leukocyte adherence inhibition test was used to detect cell-mediated immunity against antigens of the infecting fungi in patients with dermatophytosis. The species-specific diagnosis thus obtained was in all cases consistent with the eventual results of mycological examination. Most of the patients also produced a specific circulating blocking factor, the detection of which may be a useful guide to the success of treatment. Immunological reactivity against Candida albicans was also observed.

Summary A factor in the sera of patients with systemic lupus erythematosus (SLE) reduced the response of their lymphocytes to phytohaemagglutinin (PHA) demonstrated by mixed leukocyte migration inhibition. Lymphocyte responses to PHA in horse serum were unimpaired. After treatment with Levamisole for 3 months, responses to PHA in autologous sera returned to normal.

SUMMARY Severe warts of 20 years duration, highly resistant to therapy, were found to contain a soluble factor which blocked the local expression of cellular immunity, without affecting systemic immune respon- siveness. This finding enabled us to propose therapy by infection, and this had a limited success.