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Soils with marginal to deficient levels of selenium (Se) are widespread in the northwest, northeast, and southeast US. Supplementation to the diet of forage-grazing beef cattle with a vitamin-mineral mix containing additional Se is recommended in these geographic regions. We have reported that the form of supplemental Se provided to Angus-cross beef cows can affect circulating levels of progesterone (P4) on day 6 of the estrous cycle, a time when increased P4 is known to promote fertility. The objectives of this study were to (1) confirm and expand upon our initial report that the form of Se provided to cows affects early luteal-phase concentrations of systemic P4, (2) determine the effects of the form of Se on concentrations of P4 during gestation, and (3) determine the effects of the form of Se on concentrations of prolactin (PRL) during lactation. Throughout this study, Angus-cross beef cows had ad libitum access to a vitamin-mineral mix containing 35 ppm of Se in either an inorganic form (ISe) or a 1:1 mix of inorganic and organic forms (MIX). We observed a MIX-induced increase (p = 0.006) in systemic concentrations of P4 on day 7 but not on days 4 or 10 of the estrous cycle, consistent with our earlier report. We observed a MIX-induced increase (p = 0.02) in the systemic concentration of P4 at months 1, 3, 5, and 7 of gestation, and a MIX-induced decrease (p &lt, 0.05) in systemic concentrations of PRL at months 5 and 6 of lactation. In summary, the form of Se provided to cows can be manipulated to affect the early luteal phase and gestational concentrations of P4, and postpartum concentrations of PRL.

Increased tissue redox state may result in sub-optimal growth. Our goal was to determine if glutathione (GSH) content and expression of proteins involved with GSH metabolism change in longissimus dorsi (LD), subcutaneous adipose (SA), and liver tissues of growing vs. finishing steer phenotypes. Tissues were taken from 16 Angus steers (BW = 209 ± 29.4 kg) randomly assigned (n = 8) to develop through Growing (final BW = 301 ± 7.06 kg) vs. Finished (final BW = 576 ± 36.9 kg) growth phases, and at slaughter had achieved different rib-eye area (REA) (53.2, 76.8 cm2), marbling scores (296, 668), and 12th rib adipose thickness (0.54, 1.73 cm), respectively (Amino Acids, doi:10.1007/s00726-018-2540-8). GSH content (mg/g wet tissue) was determined by a commercial assay and the relative content of target protein and mRNA in tissue homogenates was determined by Western blot and reverse-transcribed PCR analyses, respectively. The effect of growth phase (Finished vs. Growing) was assessed by ANOVA using the GLM procedure of SAS. The LD of Finished steers had more (P 0.57). Principal component analysis found that GSH content of LD was associated with REA and marbling score. The SA of Finished steers had less (P 0.32). The liver of Finished steers had less (P < 0.02) mRNA content of GSH synthesizing (GCLC, 39%; GSS 29%) and metabolizing (GPX1, 30%) enzymes, and more (P < 0.01) GSTM1 metabolizing enzyme (114%). The change in GSH content as steers fattened indicate an increased antioxidant capacity in the LD of Finished steers, and a decreased antioxidant capacity in SA, consistent with changes in enzyme and transporter expression. Changes in liver enzyme and transporter expression were consistent with no change in GSH content. The relationship of EAAC1 regulatory proteins (GTRAP3-18, ARL6IP1) to GSH, EAAC1, and GS content differs and changes as Growing steers develop into Finished phenotypes. These findings provide mechanistic insight into how antioxidant capacity occurs in tissues of economic and metabolic importance as cattle fatten.

The objective of this 49-d experiment was to test effects of cecal oxytetracycline (OTC) infusion, and dietary avidin and biotin supplementation on the biotin status of nongravid gilts. Twenty-eight crossbred gilts with an initial age of 160 d and BW of 120 kg were surgically fitted with a T-cannula in the terminal ileum, a cecal fistula, and an indwelling catheter in the anterior vena cava, and allotted to 7 dietary treatments. Treatments with the basal semipurified (SP) diet fed at 1.86 kg/d were: SP-1, negative control; SP-2, positive control with 270 μg of biotin/kg; SP-3, with spray-dried egg albumen (EA, 100 g/d) and OTC (2.56 g/d by cecal infusion); and SP-4, with EA, OTC, and 700 μg of biotin/kg. Treatments with the basal corn-soybean meal (CS) diet fed at 1.80 kg/d were: CS-1, negative control; CS-2, with EA and OTC; and CS-3, with EA, OTC, and 700 μg of biotin/kg. Response criteria were: fecal bacteria counts; plasma concentrations of biotin, glucose, and urea N (PUN); liver pyruvate carboxylase (PC) activity; kidney and epithelial tissue histology; ileal and fecal biotin concentrations; ileal and total tract N and energy utilization; daily gilt observation; and BW gain. Blood samples were collected every 7 d with serial samples collected on d 49. Total urine collections and fecal grab samples were made twice daily from d 44 to 49. Gilts were killed on d 50 and liver, kidney, and skin samples were collected. No gilts had symptoms of biotin deficiency. There were no treatment differences in BW gain, plasma glucose concentrations, liver PC activity, kidney and epithelial tissue histology, or fecal bacteria counts. Ileal and total tract N and energy digestibilities (%) did not differ among treatments within the same protein source, with greater (P ≤ 0.05) values for gilts on the SP treatments than the CS treatments. However, N retained/N absorbed and N retained/N intake (%) were less (P ≤ 0.05) and PUN concentrations were greater (P ≤ 0.05) for SP treatments with cecal OTC infusion. The overall fecal biotin concentration mean was 2.6-fold greater than the overall ileal biotin concentration mean. In conclusion, no gilts in the current experiment became biotin deficient because the biotin requirements were met primarily by microbial synthesis and absorption of biotin from the distal small intestine and large intestine, with corn and soybean meal contributing endogenous biotin. Therefore, supplementation of diets for gilts entering the breeding herd with 100% of the current NRC biotin requirement for sows is adequate.

Crossbred pigs (n=288) were used to test the interactive effects of dietary fat source and slaughter weight on dissected carcass composition and fatty acid composition of composite carcass samples. Pigs were blocked by initial BW, and within each of 9 blocks, pens (8 pigs/pen) were randomly assigned to either control corn-soybean meal grower and finisher diets (Ctrl) or diets formulated with 5% beef tallow (BT), poultry fat (PF), or soybean oil (SBO). Immediately after treatment allotment, as well as at mean block BW of 45.5, 68.1, 90.9, and 113.6 kg, 1 pig was randomly selected from each pen and slaughtered, and primal cuts from right carcass sides were dissected into muscle, fat, bone, and skin components. Muscle and fat tissues were then ground, and random composite samples were collected from each carcass for fatty acid composition analysis. Fat source did not alter pork primal cut yields (P >or= 0.294), nor were the percentages of carcass muscle (P=0.213), fat (P=0.502), and bone (P=0.551) affected by dietary fat source. Conversely, percentages of the whole shoulder and ham decreased linearly (P

Crossbred pigs (n=288) were used to test the interactive effects of dietary fat source and slaughter weight on live performance, carcass traits, and fatty acid composition of the LM. Pigs were blocked by initial BW, and, within each of 9 blocks, pens (8 pigs/pen) were randomly assigned to either control corn-soybean meal grower and finisher diets devoid of added fat (Ctrl) or diets formulated with 5% beef tallow (BT), poultry fat (PF), or soybean oil (SBO). Immediately after treatment allotment, as well as at mean block BW of 45.5, 68.1, 90.9, and 113.6 kg, 1 pig was randomly selected from each pen, slaughtered, and allowed to chill for 48 h at 1 degrees C. Backfat was measured on the right sides, and a sample of the LM was removed for fatty acid composition analysis. Regardless of source, inclusion of fat in swine diets did not (P >or= 0.349) affect ADG, ADFI, or G:F. Furthermore, carcasses from pigs fed diets formulated with 5% fat had greater (P=0.013) average backfat depths than those from pigs fed the Ctrl diet. Body weight, carcass weight, and backfat depths increased (P

Crossbred pigs (n = 288) were used to test the interactive effects of dietary fat source and slaughter weight on the fatty acid composition of subcu- taneous fat. Pigs were blocked by initial BW (28.1 kg), and, within blocks, pens (8 pigs/pen) were randomly assigned to either grower and finisher diets devoid of added fat (Ctrl) or diets formulated with 5% beef tal- low (BT), poultry fat (PF), or soybean oil (SBO). Im- mediately after treatment allotment, as well as at mean block BW of 45.5, 68.1, 90.9, and 113.6 kg, 1 pig was randomly selected from each pen, slaughtered, and, within 1 h postmortem, samples of backfat were re- moved from each carcass between the 4th and 8th tho- racic vertebra and separated into the inner, middle, and outer layers for fatty acid composition analysis. During the first 17.4 kg of BW gain, percentages of all SFA increased by more than 4% in subcutaneous fat of pigs fed the Ctrl and BT diets, but decreased by 4.4 and 7.7% in pigs fed the PF and SBO diets, respectively (fat source × slaughter weight, P 0.05) PUFA percentages, the greatest (P < 0.05) and least (P < 0.05) IV were in the outer and middle layers, respectively. As expected, the fat source included in swine diets was responsible for the fatty acid compositional changes in subcutaneous fat, yet the results of this study indicate that feeding 5% SBO dramatically increased the polyunsaturation of subcutaneous fat within the first 17.4 kg of BW gain, with backfat IV exceeding 80 thereafter.

An experiment involving 25 experiment stations in the North Central and Southern regions (NCR-42 and S-288, respectively) was conducted to assess the degree of uniformity of diet mixing among stations and to assess the variability among station laboratories in chemical analysis of mixed diets. A fortified corn-soybean meal diet was mixed at each station using a common diet formula (except for vitamin and trace-mineral additions). The diet was calculated to contain 14% crude protein (CP), 0.65% Ca, 0.50% P, and 125 ppm Zn (based on 100 ppm added Zn). After mixing, samples were collected from the initial 5% of feed discharged from the mixer, after 25, 50, and 75% was discharged, and from the final 5% of discharged feed. The five samples were sent to the University of Kentucky, finely ground, and divided into subsamples. Each set of five subsamples from each station was distributed to three randomly selected stations for analysis of CP, Ca, P, and Zn (i.e., each station analyzed five diet sub-samples from three other stations). In addition, two commercial and two station laboratories analyzed composites of the five subsamples from each of the 25 mixed diets. Based on the laboratories that analyzed all diets, means were 13.5, 0.65, and 0.52%, and 115 ppm for CP, Ca, P, and Zn, respectively. Ranges of 11.8 to 14.6% CP, 0.52 to 0.85% Ca, 0.47 to 0.58% P, and 71 to 182 ppm of Zn were found among the 25 diet mixes. The coefficients of variation among the 25 diet samples for CP, Ca, P, and Zn were 4.3, 9.3, 4.1, and 17.4%, and among the 25 laboratories were 3.6, 12.5, 10.7, and 11.1%, respectively. Overall analyses of the five sub samples were, respectively, CP: 13.4, 13.6, 13.4, 13.5, and 13.4% (P < 0.06); Ca: 0.66, 0.67, 0.67, 0.66, and 0.67%; P: 0.50,0.51,0.51,0.50, and 0.50%; and Zn: 115, 116, 112, 113, and 120 ppm (P < 0.001). Diets were not uniformly mixed at all stations (station x sample No. was P < 0.08 for Ca and P < 0.01 for CP, P, and Zn). Among stations, the range of the five samples, expressed as a percentage of the mean and averaged for CP, Ca, P, and Zn, varied from +/- 1.1% (i.e., 98.9 to 101.0%) to +/- 12.9% (84.6 to 110.4%), with an overall average of +/- 5.2%. Neither type nor volume of mixers was related to mixing uniformity. The results suggest that uniformity of diet mixes varies among experiment stations, that some stations miss their targeted levels of nutrients (especially Zn), and that the variability among experiment station laboratories in analysis of dietary Ca, P, and Zn in mixed diets is quite large.

The objective of this 49-d experiment was to test effects of cecal oxytetracycline (OTC) infusion, and dietary avidin and biotin supplementation on the biotin status of nongravid gilts. Twenty-eight crossbred gilts with an initial age of 160 d and BW of 120 kg were surgically fitted with a T-cannula in the terminal ileum, a cecal fistula, and an indwelling catheter in the anterior vena cava, and allotted to 7 dietary treatments. Treatments with the basal semipurified (SP) diet fed at 1.86 kg/d were: SP-1, negative control; SP-2, positive control with 270 μg of biotin/kg; SP-3, with spray-dried egg albumen (EA, 100 g/d) and OTC (2.56 g/d by cecal infusion); and SP-4, with EA, OTC, and 700 μg of biotin/kg. Treatments with the basal corn-soybean meal (CS) diet fed at 1.80 kg/d were: CS-1, negative control; CS-2, with EA and OTC; and CS-3, with EA, OTC, and 700 μg of biotin/kg. Response criteria were: fecal bacteria counts; plasma concentrations of biotin, glucose, and urea N (PUN); liver pyruvate carboxylase (PC) activity; kidney and epithelial tissue histology; ileal and fecal biotin concentrations; ileal and total tract N and energy utilization; daily gilt observation; and BW gain. Blood samples were collected every 7 d with serial samples collected on d 49. Total urine collections and fecal grab samples were made twice daily from d 44 to 49. Gilts were killed on d 50 and liver, kidney, and skin samples were collected. No gilts had symptoms of biotin deficiency. There were no treatment differences in BW gain, plasma glucose concentrations, liver PC activity, kidney and epithelial tissue histology, or fecal bacteria counts. Ileal and total tract N and energy digestibilities (%) did not differ among treatments within the same protein source, with greater (P ≤ 0.05) values for gilts on the SP treatments than the CS treatments. However, N retained/N absorbed and N retained/N intake (%) were less (P ≤ 0.05) and PUN concentrations were greater (P ≤ 0.05) for SP treatments with cecal OTC infusion. The overall fecal biotin concentration mean was 2.6-fold greater than the overall ileal biotin concentration mean. In conclusion, no gilts in the current experiment became biotin deficient because the biotin requirements were met primarily by microbial synthesis and absorption of biotin from the distal small intestine and large intestine, with corn and soybean meal contributing endogenous biotin. Therefore, supplementation of diets for gilts entering the breeding herd with 100% of the current NRC biotin requirement for sows is adequate.

A cooperative research study involving three experiments and 2,318 pigs was conducted at 12 research stations to evaluate the protein (lysine) requirements of barrows and gilts. The two sexes were penned separately and fed fortified corn-soybean meal diets containing protein levels ranging from 12.0 to 17.2%. Lysine levels in these diets ranged from .52 to .90%. Protein levels in Exp. 1 were 12, 14, and 16%; in Exp. 2, protein levels were 13, 14, 15, and 16%; and in Exp. 3, they were 13.2 15.2, and 17.2%. Fat (5%) was added to one-half of the diets in Exp. 3. Each station that participated contributed a minimum of two replicate pens of pigs per diet-sex combination in a given experiment. Average initial and final weights were 35 and 99 kg in Exp. 1 and 51 and 105 kg in Exp. 2 and 3, respectively. At the end of the test period, pigs were slaughtered and hot carcass weight, 10th rib fat depth, and longissimus muscle area were measured. Percentage of carcass muscle was estimated from these data. Overall, barrows gained weight faster than gilts (P < .01), but gilts required less feed per unit of gain (P < .05) and had less backfat, larger longissimus muscle areas, and a greater percentage of carcass muscle (P < .01) than did barrows. Lean growth rate was similar for barrows and gilts (332 vs 329 g/d). Increasing the dietary protein or lysine level resulted in improved rate and efficiency of gain and increased carcass leanness and lean growth rate in gilts, but the increase was less pronounced or did not occur in barrows, resulting in protein level x sex interactions. Feeding low-protein (12 or 13%) diets decreased performance and carcass leanness to a greater extent in gilts than in barrows. The pooled data from the three experiments indicated that most traits tended to reach a plateau at 13% CP (.60% lysine) in barrows, whereas in gilts, weight gains, feed/gain, carcass muscle, and lean growth rate continued to improve, but at a decreasing rate, with up to 17.2% CP (.90% lysine). The results indicate that gilts require higher concentrations of dietary amino acids to maximize lean growth rate than do barrows.

Crossbred pigs (n=288) were used to test the interactive effects of dietary fat source and slaughter weight on dissected carcass composition and fatty acid composition of composite carcass samples. Pigs were blocked by initial BW, and within each of 9 blocks, pens (8 pigs/pen) were randomly assigned to either control corn-soybean meal grower and finisher diets (Ctrl) or diets formulated with 5% beef tallow (BT), poultry fat (PF), or soybean oil (SBO). Immediately after treatment allotment, as well as at mean block BW of 45.5, 68.1, 90.9, and 113.6 kg, 1 pig was randomly selected from each pen and slaughtered, and primal cuts from right carcass sides were dissected into muscle, fat, bone, and skin components. Muscle and fat tissues were then ground, and random composite samples were collected from each carcass for fatty acid composition analysis. Fat source did not alter pork primal cut yields (Por= 0.294), nor were the percentages of carcass muscle (P=0.213), fat (P=0.502), and bone (P=0.551) affected by dietary fat source. Conversely, percentages of the whole shoulder and ham decreased linearly (P0.001), and the percentages of loin and belly increased (P0.001) linearly with increasing slaughter weight. Moreover, linear decreases (P0.001) in carcass muscle, bone, and skin, as well as a linear increase (P0.05) in carcass fat, were observed as slaughter weight increased from 28.1 to 113.6 kg. Composite samples from pigs fed the BT or Ctrl diets had greater (P0.05) proportions of SFA, particularly oleic and stearic acids, than those from pigs fed the PF and SBO diets when slaughtered at 45.5, 68.1, and 90.9 kg (fat source x slaughter weight, P0.001). Percentages of MUFA (including palmitoleic, oleic, and cis-vaccenic acids) decreased (P0.05), and percentages of all PUFA, especially linoleic and linolenic acids, and iodine values increased (P0.05) in samples from SBO-fed pigs as slaughter weight increased from 28.1 to 113.6 kg (fat source x slaughter weight, P0.001). Dietary fat source did not affect carcass composition; however, including 5% SBO in swine diets increased the polyunsaturation of pork, which could lead to economic ramifications associated with soft pork and pork fat.

A cooperative research study involving 635 gilts was conducted at eight research stations to further estimate the lysine requirement of finishing gilts. Dietary crude protein levels of the five dietary treatments ranged from 16.0 to 24.4% with calculated lysine levels of .80, .95, 1.10, 1.25, or 1.40%. Each sta- tion contributed a minimum of two replicate pens of pigs per treatment. Average initial and final weights were 53.6 and 116.4 kg, respectively. At the end of the experimental period, pigs were killed and hot carcass weight, 10th-rib fat depth, and longissimus muscle area were measured. Carcass fat-free lean percentage and fat-free lean gain were estimated from these data. Daily lysine intakes averaged 21.8, 25.9, 30.5, 34.3, and 37.8 g/d for the five treatment groups, respectively. Increas- ing the dietary lysine from .80 to .95% numerically increased weight gain and gain:feed, but these in- creases were not maintained at higher levels of dietary lysine. Overall, rate and efficiency of gain decreased (cubic, P < .01) with increasing dietary lysine. Carcasses were leaner at the two higher levels of dietary lysine as evidenced by reduced 10th rib backfat (linear, P < .01), increased longissimus area (quadratic, P < .04), and increased percentage of estimated fat-free lean (lin- ear, P < .01). Carcass fat-free lean gain was not influ- enced by dietary lysine except for a small numerical improvement (P < .11) at the .95% level of dietary lysine that paralleled the improvement in body weight gain. The results indicate that the dietary lysine requirement of finishing gilts with a mean carcass fat-free lean growth rate of 306 g/d from 54 to 116 kg body weight is probably no higher than .80% of the diet to achieve maximum rate and efficiency of body weight gain and carcass lean growth rate. The results also indicate that higher dietary lysine levels may increase carcass lean- ness in finishing gilts, possibly due to reduced intake of NE. Whether this response is due to the effects of lysine alone, protein (i.e., other amino acids), or soybean meal is unknown.

Twenty-six split-brain rhesus monkeys learned and remembered 8 go/no-go discriminations of monkey faces significantly better with the right hemisphere than with the left. Four discriminations required differentiating individual identity with expression held constant, and 4 required discriminating facial expression with identity held constant. There was no significant difference in the degree of laterality shown for these 2 types of problems. Female monkeys were more lateralized for learning to discriminate faces than were males. This sex difference in laterality was significant for learning but not for memory. Laterality for the facial discriminations was not significantly related to handedness of the monkeys. Overall, rhesus monkeys, like humans, show a right-hemispheric superiority for facial processing.

A regional study involving a total of 618 nursery pigs with 468 continuing through the grower-finisher period evaluated the feeding duration of a Phase 1 starter diet (1, 2, or 3 wk) to 23-d old weanling pigs of two weaning weights (5.5 or 7.5 kg). The study was a 3 x 2 factorial arrangement of treatments in a randomized complete block design conducted in 19 replicates during the nursery period, with 14 replicates continuing through the grower-finisher period. Upon completion of feeding the Phase 1 diet for the experimental period, pigs were fed a Phase 2 diet (total of 5 wk for both Phases), whereupon a corn-soybean meal mixture formulated to .80% lysine was fed during the grower (to 56 kg BW) and a .65% lysine diet to a final body weight of 105 kg. Station effects were significant (P.05) but station x treatment responses were not (P.15). Pigs with heavier weaning weights gained faster (P.01) and consumed more feed (P.01) during each week of the nursery period. Nursery pig gains (P.06) and gain: feed ratios improved (P.01) when the Phase 1 diet had been fed for either 2 or 3 wk for both pig weight groups. There was no interaction response during the nursery period between weaning weight or duration of feeding the Phase 1 diet on daily gains or feed intake measurements; however, pigs in the heavier weight group were more efficient (P.05) in feed utilization when fed the Phase 1 diet for 2 or 3 wk. During the grower-finisher period, gains were higher (P.01) with the heavier pig group. When the Phase 1 diet had been fed for either 2 or 3 wk to the pigs of either weight group, gains (P.01) and feed efficiency (P.05) were improved. There was no evidence of compensatory growth for the lower weight pig group during the subsequent grower or finisher periods. Pigs with heavier weaning weights reached 105 kg BW approximately 8 d sooner (P.01) and consumed less total feed (P.05) from weaning to 105 kg than those in the lower weight group. Feeding the Phase 1 diet for 2 wk to pigs of either weight group reduced the time from weaning to 105 kg BW, but weaning heavier pigs seemed to have a greater effect on postweaning performance than the feeding duration of a Phase 1 diet.

Summary Background This study was designed to evaluate the efficacy and toxicity of a 12-week alternating weekly chemotherapy regimen for advanced Hodgkin’s disease. Consolidative irradiation of residual masses was used in selected cases. Patients and methods Eighty-three patients with newly diagnosed advanced Hodgkin’s disease (bulky stage IIA, stage IIB-IVB) or with progressive disease after extended field radiotherapy for early stage disease were included in this study. The patients were treated for 12 weeks with PACE BOM comprising oral prednisolone together with intravenous doxorubicin, cyclophosphamide and etoposide alternating weekly with intravenous bleomycin, vincristine and methotrexate. Limited field adjuvant radiotherapy was also given to 21 patients with localised persistent radiological abnormalities visible on chest X-ray after chemotherapy. The study end points were overall survival, failure free survival (FFS) and toxicity, particularly with respect to reproductive function. Results Results: With a median post treatment follow up of 52 months the actuarial 5-year overall survival is 90% (confidence interval 81%–95%) and FFS is 64% (52%–74%). This treatment was well tolerated and fertility was maintained in a high proportion of young adults. Conclusions The brief duration PACE BOM regimen with or without radiotherapy appears to be comparable in efficacy to other doxorubicin containing regimens, with a favourable toxicity profile. Randomised clinical trials are now needed to evaluate the role of this and comparable initial treatment approaches to advanced Hodgkin’s disease.

Large White x Landrace primiparous and multiparous sows (n = 115) were used to evaluate the tryptophan needs of lactating sows fed diets supplemented with crystalline lysine to contain .75% lysine. Sows were fed 1.8 kg of their allotted diets from d 110 of gestation until parturition and then were allowed ad libitum access to diets analyzed to contain either .12 (n = 58) or .17% (n = 57) tryptophan during a 21-d lactation. Diets were created by crystalline tryptophan and lysine additions to a corn-soybean meal basal diet that contained .12% tryptophan. Tryptophan level in the lactation diet did not affect number or weight of pigs at 21 d (P.10). Sows fed .17% tryptophan were heavier at d 21 of lactation than those fed .12% tryptophan (P = .09) due to less weight loss during the 21-d lactation (P = .09). Feed intake was greater (P.05) for sows fed .17% tryptophan than for sows fed .12% tryptophan. A reference diet analyzed to contain .11% tryptophan and .63% lysine was fed to an additional 11 sows only as a baseline for measuring plasma urea nitrogen and amino acids. Plasma tryptophan concentrations were higher (P.05) for sows fed .17% tryptophan than for sows not fed added L-tryptophan. Among sows fed the low-tryptophan diets, sows fed the reference diet (.60% lysine) had higher (P.05) plasma phenylalanine and valine concentrations than sows fed .75% lysine. Diet did not affect plasma concentrations of any other essential amino acid (P.10). Plasma urea N levels were lower (P = .11) for sows fed the diet supplemented with tryptophan. Lactating sows allowed ad libitum access to diets containing .75% lysine benefited from higher feed intake and lower weight loss when dietary tryptophan levels were increased from .12 to .17%.

When a diagnosis of cancer has been made, an evaluation of the extent of spread is needed. Different types of neoplasms have different effects. Hematological or “fluid” malignancies predominantly affect the bone marrow, spleen, liver, and lymph nodes, but can involve other sites such as the central nervous system or testes. “Solid” tumors, such as those of the lung, bowel, or breast, invade neighboring structures and spread via the lymphatics to regional nodes and via the blood stream to distant sites. Patterns of spread are reasonably predictable, and laboratory or radiologic investigations or studies for staging of site-specific neoplasms reflect this. The clinical examination and results of these investigations form the basis of classical staging, as shown in Table 1. If the clinical stage reflects the “true” pathological stage as, for example, carcinoma in situ of the uterine cervix or stage I laryngeal cancer, then the chances of cure following local treatment are high. If the investigations show evidence of distant spread, then local treatment, however radical, will not cure the patient. Staging provides part of the basis upon which rational treatment decisions are made.

Diagnosis may be defined as a “formal statement about the nature of a patient’s disease.” An accurate diagnosis can be made only after the clinician has obtained a full history, conducted a complete physical examination, and reviewed the results of relevant laboratory or radiologic investigations. This triad of history, examination, and investigation requires emphasis, and the reason is clear: cancer is an emotive word for a disease that is potentially life-threatening. A diagnosis of cancer represents the beginning of a process that may be long and difficult for the patient. If the physician’s credibility and the patient’s confidence are to be maintained for the duration of this process, it is crucial the diagnosis be correct at the outset. During the period of searching for a diagnosis, the patient needs explanations of why every test is being recommended and performed; when a diagnosis is reached, he or she needs to be told this in understandable terms, with the relevant implications and a plan of future management.

Radiotherapy is the therapeutic use of high-energy ionizing radiation. These are either electromagnetic waves consisting of X-rays and gamma rays, or subatomic particles such as B particles, high-energy electrons, and neutrons. Ionizing radiation penetrates tissues to different depths according to its type of energy and physical nature. The free radicals produced by ionizing radiation react with a wide variety of essential macromolecules within the cells. The important reactions, however, are those that occur with DNA (Fig. 1). Because of the unique function of many parts of this molecule, DNA damage with loss of integrity leads to cell death or muta-genesis. By damaging DNA, radiation interferes with cell division. This process is unselective; it occurs both in cells of normal tissues and in those of tumors. The therapeutic usefulness of radiotherapy, therefore, depends on the differential sensitivity of some tumors to irradiation, on careful treatment planning and dose prescription to minimize normal tissue damage, and on the patient’s tolerance to radiation damage to parts of some organs. Radiotherapy treatment planning is an important part of the radiation oncologist’s work.

A cooperative research study involving three experiments and 2,318 pigs was conducted at 12 research stations to evaluate the protein (lysine) requirements of barrows and gilts. The two sexes were penned separately and fed fortified corn-soybean meal diets containing protein levels ranging from 12.0 to 17.2%. Lysine levels in these diets ranged from .52 to .90%. Protein levels in Exp. 1 were 12, 14, and 16%; in Exp. 2, protein levels were 13, 14, 15, and 16%; and in Exp. 3, they were 13.2 15.2, and 17.2%. Fat (5%) was added to one-half of the diets in Exp. 3. Each station that participated contributed a minimum of two replicate pens of pigs per diet-sex combination in a given experiment. Average initial and final weights were 35 and 99 kg in Exp. 1 and 51 and 105 kg in Exp. 2 and 3, respectively. At the end of the test period, pigs were slaughtered and hot carcass weight, 10th rib fat depth, and longissimus muscle area were measured. Percentage of carcass muscle was estimated from these data. Overall, barrows gained weight faster than gilts (P.01), but gilts required less feed per unit of gain (P.05) and had less backfat, larger longissimus muscle areas, and a greater percentage of carcass muscle (P.01) than did barrows. Lean growth rate was similar for barrows and gilts (332 vs 329 g/d). Increasing the dietary protein or lysine level resulted in improved rate and efficiency of gain and increased carcass leanness and lean growth rate in gilts, but the increase was less pronounced or did not occur in barrows, resulting in protein level x sex interactions. Feeding low-protein (12 or 13%) diets decreased performance and carcass leanness to a greater extent in gilts than in barrows. The pooled data from the three experiments indicated that most traits tended to reach a plateau at 13% CP (.60% lysine) in barrows, whereas in gilts, weight gains, feed/gain, carcass muscle, and lean growth rate continued to improve, but at a decreasing rate, with up to 17.2% CP (.90% lysine). The results indicate that gilts require higher concentrations of dietary amino acids to maximize lean growth rate than do barrows.

Polysomnographic data recorded from a large sample of normal, healthy, adult volunteer subjects are reported. First and second night summary values are included. Results agree remarkably well with previously published findings and the age-related differences in sleep architecture that we found are described in detail. We also discuss some of the unique methodological problems associated with developing normative sleep values.

A cooperative research study was conducted by members of a regional committee (North Central Regional Committee on Swine Nutrition [NCR-42]) to assess the variability in nutrient composition (DM, CP, Ca, P, Se, NDF, and amino acids) of 14 sources of wheat middlings from 13 states (mostly in the Midwest). A second objective was to assess the analytical variability in nutrient assays among 20 laboratories (labs; 14 experiment station labs and six commercial labs). Wheat middlings were obtained from each participating station's feed mill. The bulk density of the middlings ranged from 289 to 365 g/L. The number of labs that analyzed samples were as follows: DM and CP, 20; Ca, 16; P, 15; Se, 7; NDF, 10; and amino acids, 9. Each lab used its own analytical procedures. The middlings averaged 89.6% DM, 16.2% CP, .12% Ca, .97% P, 36.9% NDF, .53 mg/kg Se, .66% lysine, .19% tryptophan, .54% threonine, .25% methionine, .34% cystine, .50% isoleucine, and .73% valine. As expected, there was considerable variation in nutrient composition among the 14 sources (P.01), especially for Ca (.08 to .30%) and Se (.05 to 1.07 mg/kg). "Heavy" middlings (high bulk density,335 g/L), having a greater proportion of flour attached to the bran, were lower in CP, lysine, P, and NDF than "light" middlings (310 g/L), having cleaner bran, resulting in negative correlations between bulk density and CP (r = -.61), lysine (r = -.59), P (r = -.54), and NDF (r = -.81). Each 1-percentage-point increase in CP in the wheat middlings was associated with .0235 (r2 = .61) and 2.1 (r2 = .39)-percentage-point increases in lysine and NDF, respectively. Lysine content was associated with NDF, CP, and bulk density of wheat middlings (r2 = .88). There was considerable variation among laboratories (P.01) in analysis of all nutrients. The CV among sources (100 x sigmaS/mean) was greater than among labs (100 x sigmaL/mean) for CP, Ca, P, Se, and NDF, but the CV among labs was greater than that among sources for DM and all of the amino acids except lysine and phenylalanine.

A cooperative research study involving members of a regional committee (North Central Regional Committee on Swine Nutrition [NCR-42]) was conducted to assess the variability in nutrient composition (DM, CP, Ca, P, Se, and amino acids) of corn and soybean meal from 16 sources (15 states, mostly in the Midwest) and to assess the analytical variability in nutrient assays among 22 laboratories (labs; 16 experiment station labs and six commercial labs). Corn samples were obtained from each participating station's feed mill during a 3-yr period (1989, 1990, and 1992), as were soybean meal samples during a 2-yr period (1989 and 1990). Both regular soybean meal (with hulls) and dehulled soybean meal were represented in the study. Samples were analyzed for DM and CP by all 22 labs, for Ca and P by 15 labs, for amino acids by 10 labs, and for Se by 6 labs. Each lab used its own analytical procedures. Samples of corn and soybean meal varied in their nutrient composition depending on the area of origin. The greatest variation among sources was in Se concentration, ranging from .02 to .29 mg/kg in corn and .08 to .95 mg/kg in soybean meal. Crude protein and lysine in corn were positively correlated, but the regression coefficient was low (r2 = .49). The relationship between CP and lysine for the two soybean meals combined was considerably stronger (r2 = .81). Lysine in corn increased by .018 percentage point and lysine in soybean meal (regular and dehulled combined) increased by .063 percentage point for each 1 percentage point increase in CP. Except for CP and Se, the analytical variability among labs was as great as, and in some cases greater than, the variability in nutrient composition among sources of corn and soybean meal. Within-lab analytical variability tended to be less than among-lab variability. Some labs performed certain analyses with considerably less variability and more accuracy than others.

A 3-yr study was conducted to evaluate the effects of biotin on sow longevity, reproductive performance and piglet performance to weaning utilizing 161 sows and 414 litters. Sows and gilts were fed a basal corn-soybean meal diet (without any antibiotic or chemotherapeutic compounds) during gestation and lactation containing either 0 or .55 ppm added biotin. The basal diet contained .17 ppm total dietary biotin based on microbiological assay. Results indicated sow culling rates and weight gains, number of live pigs at birth, pig weights at birth and weaning, and the interval from weaning to rebreeding were similar for both treatment groups. However, sows fed the diet with added biotin weaned more (P less than .05) pigs/litter overall and at gestation-lactation period 1 than did sows fed the basal diet without added biotin, although biotin did not increase (P greater than .10) the number of pigs weaned at gestation-lactation periods 2 through 5. The incidence of dermatitis, hair loss and soundness of feet and legs did not appear to be affected by adding biotin to the diet. Thus, the addition of .55 ppm biotin to a corn-soybean meal diet fed during gestation and lactation did not improve any of the criteria measured except number of pigs weaned overall.

Twenty-four pigs were weaned at four weeks of age and fed either spray dried egg albumen (DA) or autoclaved DA (ADA) as the only protein source were used to evaluate plasma and hepatic parameters as indicators of biotin status. Pigs were fed one of four semipurified diets during the 42-day study: DA basal, DA + 1.1 g sulfamethazine/day (DA + S), ADA basal or ADA + .5 mg biotin/day (ADA + H). Autoclaving DA at 121 degrees C for 30 minutes reduced both the biotin binding properties of the avidin fraction and the trypsin inhibitor activity of DA. Pigs fed ADA and ADA + H had greater (P less than .05) liver pyruvate carboxylase (EC 6.4.1.1) activity and DNA concentrations, lower (P less than .05) plasma urea nitrogen levels and greater and more efficient (P less than .05) weight gain than either DA or DA + S fed pigs. Biotin supplementation further enhanced (P less than .05) liver DNA concentration but had no effect on the liver levels of RNA or total protein. Plasma levels of glucose and free fatty acids or blood levels of lactate and pyruvate were not influenced by the addition of biotin to the ADA basal diet.

A surgical procedure was developed for the simultaneous cannulation of the ileum and fistulation of the cecum in breeding-age gilts to study the effects of enteric microflora on the nutritional requirements and/or status of the pig. Flexible T-shaped cannulae were made from plastic tubing, placed surgically in the caudal part of the ileum, and exteriorized in the right paralumbar fossa. After the exteriorization of the cecal apex in the right flank area, a cecal fistual was made caudoventral to the ileal cannula. Prececocolonic contents could be collected from the ileal cannulae and/or substances could be infused into the cecum. The flexible cannulae were light weight (35 g), were easily replaced when dislodged with minimal tissue trauma and minimal discomfort to the animal, and had good animal tolerance and patency in long-term experiments. The cecal fistulae allowed the direct introduction of various substances into the cecum. There was little external projection from the abdominal wall, and the fistulae were subject to minimal leakage. The procedure did not adversely affect the subsequent health or performance of the 43 gilts used in the experiment. Postmortem examination of gilts euthanatized 12 to 26 weeks postoperatively revealed normal tissue adhesions around the surgical sites with no detrimental effects on the gastrointestinal tract.

SEVERAL investigations dealing with interocular transfer of learning of visual discriminations in split-brain cats and monkeys support the general conclusion that brain bisection including the optic chiasm and posterior corpus callosum restricts the learning and memory of the discriminations to the trained hemisphere. These tasks cannot be correctly performed through the other eye until it has received comparable training, in contrast to the immediate interocular transfer usually shown by normal or chiasm-sectioned controls1–3. This generalization has been qualified by more recent studies indicating that transfer of learning of brightness4,5 and pattern6 discriminations in split-brain cats, and of brightness and colour discriminations in split-brain monkeys7, does occur under certain conditions. Transfer of colour and brightness learning in split-brain monkeys would, therefore, seem to be dependent on the conditions used. It appeared advisable, in reference to future studies on vision, to see if transfer of these tasks takes place under the conditions at present being used in this laboratory.

Several experimental approaches for establishing the effectiveness of the interruption of an explosive train are presented. It is recommended that a combination of the approaches described be used to evaluate the safety of any new explosive train.