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Fifty-four multiparous beef cows with calves were used to evaluate the effects of Mo source (feed or water) on reproduction, mineral status, and performance over two cow-calf production cycles (553 d). Cows were stratified by age, body weight, liver Cu and Mo status, and were then randomly assigned to one of six treatment groups. Treatments were: 1) Negative control (NC; basal diet with no supplemental Mo or Cu); 2) Positive control (NC + Cu; 3 mg of supplemental Cu/kg DM); 3) NC + 500 µg Mo/L from Na2MoO4·2H2O supplied in drinking water; 4) NC + 1000 µg Mo/L of Na2MoO4·2H2O supplied in drinking water; 5) NC + Mo 1000-water + 3 mg of supplemental Cu/kg DM; and 6) NC + 3.0 mg of supplemental Mo/kg diet DM from Na2MoO4·2H2O. Animals were allowed ad libitum access to both harvested grass hay (DM basis: 6.6% crude protein; 0.15% S, 6.7 mg Cu/kg, 2.4 mg Mo/kg) and water throughout the experiment. Calves were weaned at approximately 6 months of age each year. Dietary Cu concentration below 10.0 mg Cu/kg DM total diet reduced liver and plasma Cu concentrations to values indicative of a marginal Cu deficiency in beef cows. However, no production parameters measured in this experiment were affected by treatment. Results suggest that Mo supplemented in water or feed at the concentrations used in this experiment had minimal impact on Cu status and overall performance.

Fifty-four multiparous beef cows with calves were used to evaluate the effects of Mo source (feed or water) on reproduction, mineral status, and performance over two cow-calf production cycles (553 days). Cows were stratified by age, body weight, liver Cu, and Mo status and were then randomly assigned to one of six treatment groups. Treatments were (1) negative control (NC; basal diet with no supplemental Mo or Cu), (2) positive control (NC + Cu; 3 mg of supplemental Cu/kg DM), (3) NC + 500 µg Mo/L from Na2MoO4·2H2O supplied in drinking water, (4) NC + 1000 µg Mo/L of Na2MoO4·2H2O supplied in drinking water, (5) NC + Mo 1000-water + 3 mg of supplemental Cu/kg DM, and (6) NC + 3.0 mg of supplemental Mo/kg diet DM from Na2MoO4·2H2O. Animals were allowed ad libitum access to both harvested grass hay (DM basis: 6.6% crude protein; 0.15% S, 6.7 mg Cu/kg, 2.4 mg Mo/kg) and water throughout the experiment. Calves were weaned at approximately 6 months of age each year. Dietary Cu concentration below 10.0 mg Cu/kg DM total diet reduced liver and plasma Cu concentrations to values indicative of a marginal Cu deficiency in beef cows. However, no production parameters measured in this experiment were affected by treatment. Results suggest that Mo supplemented in water or feed at the concentrations used in this experiment had minimal impact on Cu status and overall performance.

High solubility of certain trace minerals (TM) in the rumen can alter nutrient digestibility and fermentation. The objectives of the present studies were to determine the effects of TM source on 1) nutrient digestibility and ruminal fermentation, 2) concentrations of soluble Cu, Zn, and Mn in the rumen following a pulse dose of TM, and 3) Cu, Zn, and Mn binding strength on ruminal digesta using dialysis against a chelating agent in steers fed a diet formulated to meet the requirements of a high producing dairy cow. Twelve Angus steers fitted with ruminal cannulae were adapted to a diet balanced with nutrient concentrations similar to a diet for a high producing lactating dairy cow for 21 d. Steers were then randomly assigned to dietary treatments consisting of 10 mg Cu, 40 mg Mn, and 60 mg Zn/kg DM from either sulfate (STM), hydroxychloride (HTM) or complexed trace minerals (CTM). The experimental design did not include a negative control (no supplemental Cu, Mn, or Zn) because the basal diet did not meet the National Research Council requirement for Cu and Zn. Copper, Mn, and Zn are also generally supplemented to lactating dairy cow diets at concentrations approximating those supplied in the present study. Following a 14-d adaptation period, total fecal output was collected for 5-d. Following the fecal collection period, rumen fluid was collected for Volatile fatty acid (VFA) parameters. On the following day, the same diet was provided for 14 d, without supplemental Cu, Zn, and Mn. This period served as a wash-out period. A pulse dose of 100, 400, and 600 mg of Cu, Zn, Mn, respectively, from either STM, HTM, or CTM, was administered via ruminal cannulae to the steers on day 15. Over a 24-h period ruminal samples were obtained every 2-h. Following centrifugation, the supernatant was analyzed for Cu, Mn, and Zn. Ruminal solid digesta samples from times 0, 12, and 24 h after bolus dosing were exposed to dialysis against Tris-EDTA. Digestibility of NDF and ADF were lesser in STM vs. HTM and vs. CTM supplemented steers. Steers receiving HTM and CTM had greater total VFA concentrations than STM, and molar proportions of individual VFA were not affected by treatment. Ruminal soluble Cu and Zn concentrations were greater post dosing in STM and CTM supplemented steers at 2, 4, and 6 h for Cu and 4, 6, 8, 10 and 12 h for Zn when compared to HTM supplemented steers. The release of Cu and Zn from ruminal solid digesta following dialysis against Tris-EDTA at 12 and 24 h postdosing was greater for steers receiving HTM compared to those receiving STM or CTM. Results indicate trace mineral source impacts: 1) how tightly bound Cu and Zn are to ruminal solid digesta; 2) fiber digestion; 3) and ruminal total VFA concentrations.

Crossbred yearling steers ( = 360; 395 ± 33.1 kg initial BW) were used to evaluate the effects of dry-rolled corn (DRC) particle size in diets containing 20% wet distiller's grains plus solubles on feedlot performance, carcass characteristics, and starch digestibility. Steers were used in a randomized complete block design and allocated to 36 pens (9 pens/treatment, with 10 animals/pen). Treatments were coarse DRC (4,882 μm), medium DRC (3,760 μm), fine DRC (2,359 μm), and steam-flaked corn (0.35 kg/L; SFC). Final BW and ADG were not affected by treatment ( > 0.05). Dry matter intake was greater and G:F was lower ( 0.10) were observed among treatments for any of the carcass traits measured. Results indicate improved ruminal starch digestibility, reduced fecal starch concentration, and reduced DMI with decreasing DRC particle size in feedlot diets containing 20% wet distiller's grains on a DM basis.

Recent advancements in technology have made possible the use of novel, cost-efficient biomonitoring techniques which facilitate monitoring animal populations at larger spatial and temporal scales. Here, we investigated using passive acoustic monitoring (PAM) for wild primate populations living in the forest of Tai National Park, Cote d’Ivoire. We assessed the potential of using a customized algorithm for the automated detection of multiple primate species to obtain reliable estimates of species occurrence from acoustic data. First, we applied the algorithm on continuous rainforest recordings collected using autonomous recording units (ARUs) to detect and classify three sound signals: chimpanzee buttress drumming, and the loud calls of the diana and king colobus monkey. Using an occupancy modelling approach we then investigated to what extent the automated, probabilistic output needs to be listened to, and thus manually cleaned, by a human expert, to approach occupancy probabilities derived from ARU data fully verified by a human. To do this we explored the robustness of occupancy probability estimates by simulating ARU datasets with various degrees of cleaning for false positives and false negative detections. We further validated the approach by comparing it to data collected by human observers on point transects located within the same study area. Our study demonstrates that occurrence estimates from ARU data, combined with automated processing methods such as our algorithm, can provide results comparable to data collected by humans and require less effort. We show that occupancy probabilities are quite robust to cleaning effort, particularly when occurrence is high, and suggest that for some species even naive occupancy, as derived from ARU data without any cleaning, could provide a quick and reliable indicator to guide monitoring efforts. We found detection probabilities to be most influenced by time of day for chimpanzee drums while temperature and, likely, poaching pressure, affected detection of diana monkey loud calls. None of the covariates investigated appeared to have strongly affected king colobus loud call detection. Finally, we conclude that the semi-automated approach presented here could be used as an early-warning system for poaching activity and suggest additional techniques for improving its performance.

Ancillary therapy (ANC) is commonly provided in conjunction with an antimicrobial when treating calves for suspected bovine respiratory disease (BRD) in an attempt to improve the response to a suspected BRD challenge. The first experiment evaluated the effects of 3 ANC in combination with an antimicrobial in high-risk calves treated for BRD during a 56-d receiving period. Newly received crossbred steers (n = 516; initial BW = 217 ± 20 kg) were monitored by trained personnel for clinical signs of BRD. Calves that met antimicrobial treatment criteria (n = 320) were then randomly assigned to experimental ANC treatment (80 steers/experimental ANC treatment): intravenous flunixin meglumine injection (NSAID), intranasal viral vaccination (VACC), intramuscular vitamin C injection (VITC), or no ANC (NOAC). Animal served as the experimental unit for all variables except DMI and G:F (pen served as the experimental unit for DMI and G:F). Within calves treated 3 times for BRD, those receiving NOAC had lower (P < 0.01) clinical severity scores (severity scores ranged from 0 to 4 on the basis of observed clinical signs and severity) and heavier (P = 0.01) BW than those receiving NSAID, VACC, or VITC at the time of third treatment. Between the second and third BRD treatments, calves receiving NOAC had decreased (P < 0.01) daily BW loss (−0.13 kg ADG) compared with those receiving NSAID, VACC, or VITC (−1.30, −1.90, and −1.41 kg ADG, respectively). There were no differences in rectal temperature, combined mortalities and removals, or overall performance among the experimental ANC treatments. Overall, morbidity and mortality attributed to BRD across treatments were 66.5% and 13.2%, respectively. After the receiving period, a subset of calves (n = 126) were allocated to finishing pens to evaluate the effects ANC administration on finishing performance, carcass characteristics, and lung scores at harvest. Ultrasound estimates, BW, and visual appraisal were used to target a common physiological end point for each pen of calves. There were no differences among the experimental ANC observed during the finishing period (P ≥ 0.11). In summary, the use of NSAID, VACC, and VITC do not appear to positively impact clinical health and could potentially be detrimental to performance during the receiving period in high-risk calves receiving antimicrobial treatment for suspected BRD.

Summary Passive acoustic monitoring is frequently used for marine mammals, and more recently it has also become popular for terrestrial species. Key advantages are the monitoring of (1) elusive species, (2) different taxa simultaneously, (3) large temporal and spatial scales, (4) with reduced human presence and (5) with considerable time saving for data processing. However, terrestrial sound environments can be highly complex; they are very challenging when trying to automatically detect and classify vocalizations because of low signal-to-noise ratios. Therefore, most studies have used manual preselection of high-quality sounds to achieve better classification rates. Consequently, most systems have never been validated under realistic field conditions. In this study, we evaluated the performance of a passive acoustic monitoring system for four primate species in the highly noisy rain forest environment of the Tai National Park, Cote d'Ivoire. We collected 12 851 h of recordings with 20 autonomous recording units and did not preselect high-quality sounds manually. To automatically detect and classify the sounds of interest, we used an automated system built on speaker segmentation, support vector machines and Gaussian mixture models. One hundred and seventy-nine hours of recordings were used for validating the system. The system performed well in detecting the loud calls of Cercopithecus diana and Colobus polykomos with a recall of 50% and 42%, respectively. Recall rates were lower for Pan troglodytes and Procolobus badius. To determine the presence of Cercopithecus diana and Colobus polykomos with a certainty of P > 0·999, 2 and 7 h of recordings were needed, respectively. For these two species, our automated approach reflected the spatio-temporal distribution of vocalization events well. Despite the seemingly low precision, time investment for the manual removal of false positives in the system's output was only 3·5% compared to a human collecting and processing the primate vocalization data. The proposed monitoring system is already fully applicable for Cercopithecus diana and Colobus polykomos, whereas it needs further improvement for the other species tested. In principle, it can be applied to any distinctive animal sound and can be implemented for the collection of acoustic data for behavioural, ecological and conservation studies.

Thirty cross-bred steers (initial BW 452.0 ± 12.1 kg) were used to investigate the effects of Mo water concentration on performance, carcass characteristics, and mineral status of feedlot steers. The experimental design was a randomized complete block design. Steers were blocked by weight and then divided into 2 weight blocks each consisting of 15 steers. Steers were randomly assigned within block to one of 5 treatments (3 steers/treatment per block). Water treatments consisted of: 1) 0.0 µg/L, 2) 160 µg/L, 3) 320 µg/L, 4) 480 µg/L, and 5) 960 µg/L of supplemental Mo added as Na2MoO4 to the drinking water. Steers were housed in individual pens (steer = experimental unit) that contained individual 265 L water tanks for monitoring water intake. Steers were fed a growing diet for 28 d and then transitioned to a finishing diet. Block 1 steers were fed for a total of 151 d and block 2 steers were fed for a total of 112 d. Daily water intake was recorded for each steer. Steers were individually weighed on 2 consecutive days at the beginning and end of the experiment and interim weights and jugular blood samples were obtained every 28 d. Liver biopsies were obtained on d 0 and 84 from each steer within each block. Steers were transported to a commercial abattoir, slaughtered, and individual carcass data and liver samples were collected. Initial BW was used as a covariate for statistical analysis of data and significance was determined at P ≤ 0.05. No differences were observed for final BW (P0.98). Overall ADG (P0.91), DMI (P0.92), feed efficiency (P0.94), water intake (P0.40), hot carcass weight (P0.98), dressing percentage (P0.98), yield grade (P0.91), and marbling score (P0.29) did not differ across treatments. Lastly, no treatment differences were observed for liver concentrations of Cu (P0.93), Mo (P0.90) and Zn (P0.86) or plasma concentrations of Cu (P0.42), Mo (P0.43) and Zn (P0.62). These data indicate that water Mo concentration, within the range studied, had no impact on performance, mineral status, water intake, and carcass characteristics in feedlot steers.

Three hundred and seventy-three steers (approximately 7 mo of age and 247±19.4 kg) were utilized to determine the effects of trace mineral (TM) source and growth implants on trace mineral status. Steers were blocked by ranch, post-weaning treatment within ranch, stratified by initial body weight, and randomly assigned to one of 36 pens (9-12 head/pen). Treatment consisted of: i) control (no supplemental Cu, Zn, Mn, and Co), ii) inorganic trace minerals, and iii) organic trace minerals. Six pens of steers per treatment received a growth implant at the beginning of the experiment and were re-implanted during the finishing phase. The remaining steers received no growth implants. Steers were fed a corn silage-based growing diet for 56 d then were gradually switched to a high concentrate finishing diet. Treatments during the finishing phase consisted of: i) control (no supplemental Zn); ii) inorganic Zn (30 mg of Zn/kg DM from ZnSO 4 ); and iii) organic Zn (iso-amounts of organic Zn). By the end of the growing and finishing phases, implanted steers had greater (p

A meta-analysis of studies evaluating feedlot steer implant programs was conducted to evaluate the differential effects of anabolic implant dosage on feedlot performance and carcass traits. The effect sizes of the implant dosage of interest vs. negative controls and vs. other implant dosages on various dependent variables (ADG, F:G, DMI, dressing percentage [DP], HCW, yield grade, percentage Choice or higher, and marbling score) were calculated. Treatments used for comparisons included no implant, EST (20 mg estradiol benzoate + 200 mg progesterone, 36 mg zeranol, or 72 mg zeranol), ET120 (24 mg estradiol 17β + 120 mg trenbolone acetate [TBA]), and ET200 (28 mg estradiol benzoate + 200 mg TBA or 20 mg estradiol-17β + 200 mg TBA). In the first analysis, the 3 implant dosages were compared to negative control. A second analysis was conducted to compare ET120 vs. ET200 using only studies that included a direct comparison of these 2 dosages. The number of studies included in the analysis for each implant dosage and response variable ranged from 34 to 7. A mixed model was used to evaluate individual implant treatments; implant dosage was a fixed effect, and individual study was included as a random effect. All dosages had greater ADG, DMI, and HCW and lower F:G, percentage Choice, and marbling score vs. negative controls (P0.05) In the second direct comparison analysis, ET200 tended to have greater ADG (P = 0.10) and HCW (P = 0.07) and had lower F:G (P0.01) and percentage of carcasses grading Choice or greater (P0.01) vs. ET120. Differences in HCW between ET120 and ET200 diminished numerically with increasing days of implant activity (P0.01). All dosages of implants evaluated herein increased performance and decreased quality grade vs. negative controls. Combination implants containing estrogen (E) and 200 mg TBA have greater potency for growth promotion than implants containing E+120 mg TBA resulting in slightly greater performance.

Two hundred fifty-two cross-bred yearling steers (406 ± 24 kg BW) were used in a completely randomized block design with a 2 × 2 factorial arrangement of treatments (7 pens/treatment) to evaluate the effects of dietary Saccharomyces cerevisiae fermentation product (SFP) and monensin (MON) on growth performance and carcass characteristics. Dietary treatments arranged as a 2 × 2 factorial were 1) with or without SFP and 2) with or without MON. Finishing diets contained 19.7% of DM as dried distiller's grains with solubles. Both SFP and MON were added in the total mixed ration in place of an equal amount of cornmeal (DM basis; target intake = 2.8 g of SFP and 33 mg of MON/kg of dietary DM). Each treatment group was offered ad libitum access to a transition ration from d 1 to 8 and then to the finishing ration from d 9 to 125. Body weights were collected on d 0, 28, 56, 84, 110, and 125. Initial and final BW was an average of 2-d weights (d -1 and 0 and d 124 and 125, respectively). Steers were shipped for harvest on d 125. Overall ADG was decreased (P = 0.03) in steers supplemented with SFP, but final BW was similar among treatments. Feeding SFP was associated with lighter (P0.01) HCW and a greater (P = 0.01) number of carcasses grading USDA Choice. Twelfth rib fat thickness was not affected by SFP (P = 0.82) or MON (P = 0.35), but numerical decreases in 12th rib fat thickness among cattle receiving SFP or MON alone contributed to a tendency (P = 0.07) for greater 12 rib fat thickness when SFP and MON were provided. There was no effect of treatment on cost of gain (P ≥ 0.21). The effects of SFP in the current study may have been limited in heavy yearling steers due to consumption of a finishing diet containing 19.7% dried distiller's grains with solubles.

Data collected from 759 steer calves that were consigned to the South Dakota Retained Ownership Demonstration Program were utilized to examine the effect of slaughter cattle marketing method on production signals sent to beef producers. Marketing systems examined included basing price on live weight (LW), dressed weight (DW), grade and yield (G-Y), or Excel Corporation’s proposed muscle scoring system (MS). Profitability per head averaged $6.64, $23.54, $26.00, and $27.09 for the LW, DW, G-Y, and MS marketing systems, respectively. For the LW pricing system, average daily gain, cost of gain, initial feedlot weight, and days fed accounted for 86.6% of the variation in profitability. For the DW pricing system, average daily gain, dressing percentage, cost of gain, initial feedlot weight, and days fed accounted for 92.86% of the variation in profitability. Average daily gain, dressing percentage, quality grade, cost of gain, days fed, and hot carcass weight accounted for 83.1% of the variation in profit for the G-Y marketing system. Average daily gain, dressing percentage, cost of gain, days fed, carcass fatness, quality grade, and rib eye area explained 75.6% of the variation in profitability for the MS pricing system. Only the MS pricing system penalized the production of carcass fat. Current fed cattle pricing systems used in the industry fail to transfer consumer demand for lean beef to beef producers.

There are some striking similarities and some differences between the seismic reflection sections recorded across the fold and thrust belts of the southeast Canadian Cordillera, Quebec-Maine Appalachians and Swiss Alps. In the fold and thrust belts of all three mountain ranges, seismic reflection surveys have yielded high-quality images of: (1) nappes (thin thrust sheets) stacked on top of ancient continental margins; (2) ramp anticlines in the hanging walls of faults that have ramp-flat or listric geometries; (3) back thrusts and back folds that developed during the terminal phases of orogeny; and (4) tectonic wedges and regional decollements. A principal result of the Cordilleran and Appalachian deep crustal studies has been the recognition of master decollements along which continental margin strata have been transported long distances, whereas a principal result of the Swiss Alpine deep crustal program has been the identification of the Adriatic indenter, a crustal-scale wedge that caused delamination of the European lithosphere. Significant crustal roots are observed beneath the fold and thrust belts of the Alps, southeast Canadian Cordillera and parts of the southern Appalachians, but such structures beneath the northern Appalachians have probably been removed by post-orogenic collapse and/or crustal attenuation associated with the Mesozoic opening of the Atlantic Ocean.

Results of near-vertical seismic reflection profiling conducted in the western Swiss Alps are presented. All profiles were recorded using both high-fold Vibroseis and high-energy but low-fold dynamite sources, yielding two independent data sets. The Vibroseis seismic sections provide markedly superior resolution of upper crustal units down to the top of the crystalline basement. On these sections, high-impedance contrasts within the nappes are the source of strong reflections, and the basal thrust of the Penninic nappes (Penninic front) delineates a lateral change in reflection character. By comparison, the dynamite sections provide generally higher-quality images of the deep crust. In particular, they show prominent bands of strong reflections in the lower crust and a well-defined reflection Moho deepening from ~ 12 s (about 36 km) in the north to ~ 16 s (about 48 km) in the south. It is concluded that both types of data are required to resolve accurately shallow and deep structures in the Swiss Alps. Preliminary results of the dynamite survey from the most recently recorded line support proposals that shortening of the basement in the external domain has occurred, in agreement with interpretations of the ECORS-CROP seismic reflection line further south.

Two experiments were conducted to evaluate effects of ractopamine (RAC) and steroidal implant treatments on performance, carcass traits, blood metabolites, and lipogenic enzyme activity in feedlot cattle. In Exp. 1, yearling steers (n = 486; initial BW = 305 kg) were used in a 3 × 3 factorial arrangement of RAC doses of 0 (R0), 100 (R100), or 200 (R200) mg·steer(-1)·d(-1) fed for 28 d and implant regimens (implant-reimplant) of no implant-no reimplant (NI-NI), 120 mg of trenbolone acetate (TBA) and 24 mg of estradiol-17β (E17B)-no implant (RS-NI), or 80 mg of TBA and 16 mg of E17B followed by 120 mg of TBA and 24 mg of E17B (RI-RS). Except for KPH and skeletal maturity score, no RAC × implant interactions were noted (P0.10). Carcasses from R200 were 6.3 kg (P = 0.042) heavier than those from R0. Marbling, calculated empty body fat (EBF), and USDA quality grade did not differ (P0.10) among RAC treatments. The RI-RS steers had 12.6 kg (P = 0.001) and 41.1 kg (P0.001) greater HCW than RS-NI and NI-NI, respectively. Despite no difference (P0.10) in EBF, marbling score was decreased for RI-RS (P0.001) and RS-NI (P = 0.001) relative to NI-NI, resulting in 14.6 and 11.4 percentage unit fewer USDA Prime and Choice carcasses with RI-RS (P = 0.008) and RS-NI (P = 0.039) than with NI-NI. In Exp. 2, heifers (n = 48; initial BW = 347 kg) were used in a 3 × 2 factorial arrangement of RAC doses of 0 (R0) or 250 (R250) mg·heifer(-1)·d(-1) and implant regimens of none (NI), 200 mg of TBA (TO), or 200 mg of TBA and 20 mg of E17B (TE). Blood samples were collected at various times during the feeding period, and subcutaneous adipose samples were collected on d 119. For growth and carcass measurements, no RAC × implant interactions (P0.10) were detected. The RAC-supplemented heifers had greater HCW (P0.10) with no difference in marbling score. For implant regimens, TE heifers had greater HCW than the NI (P = 0.001) and TO (P = 0.037) heifers. Although EBF did not differ among implant treatments (P0.10), TE (P = 0.021) and TO (P = 0.039) had fewer Choice carcasses than NI. Heifers with implants had decreased cortisol and increased IGF-1 and NEFA (P0.10) compared with NI heifers. An implant × RAC interaction was detected (P = 0.001) for serum urea nitrogen (SUN), with TE and RAC-supplemented heifers having decreased SUN. These data suggest that the effects of implant and RAC on growth and carcass traits are independent and that USDA quality grade and marbling score can differ significantly among carcasses with similar calculated EBF values.

Mature Hereford cows (n = 28) were used to determine the effect of percentage body fat on secretion of LH and content of GnRH in the infundibular stalk-median eminence (ISME). Cows were fed to maintain, lose, or gain weight to achieve body condition scores (BCS; 1 = emaciated; 9 = obese) of 3 to 7. Then cows were fed to maintain weight and body condition. Before slaughter, estrus was synchronized using two injections of prostaglandin F2 alpha(PGF) 11 d apart. Five d after the second PGF injection, cows were given 100 micrograms of GnRH (im) and serum samples were obtained. LH was quantified using RIA. The anterior pituitary and ISME were obtained within 45 min of death. Anterior pituitary weight and LH concentration, total GnRH in the ISME, total carcass fat, and percentage carcass fat were determined. BCS of cows at the time of slaughter influenced percentage carcass fat (P less than .001), total GnRH in the ISME (P less than .02), and maximum LH after GnRH treatment (P less than .09), but did not influence pituitary weight or concentration of LH in the pituitary. Content of GnRH in the ISME averaged 76 +/- 12, 32 +/- 14, 27 +/- 13, and 24 +/- 13 ng for cows with BCS of 3, 5, 6, and 7, respectively. BCS was correlated (P less than .001) with percentage carcass fat (r = .94) and total fat in the carcass (r = .92). Total GnRH in the ISME was negatively correlated (P less than .005) with BCS (r = -.54), percentage carcass fat (r = -.55), and total carcass fat (r = -.49).(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized complete block design experiment with 360 single-source black yearling steers (average BW = 316.1 +/- 9.1 kg) fed a 91% concentrate (steam-flaked corn base) diet was conducted to evaluate the effects of supplemental vitamin A (0, 1,103, 2,205, 4,410, or 8,820 IU/kg of dietary DM) on plasma and liver vitamin A and E concentrations, lipogenic enzyme activity, marbling score, and performance of yearling steers. Final BW (586, 580, 590, 585, and 584 kg for 0, 1,103, 2,205, 4,410, and 8,820 IU of supplemental vitamin A/kg of DM, respectively) did not differ (P = 0.39) among treatments. Feed efficiency, ADG, and daily DMI did not differ (P0.10) among treatments within each 28-d period or for the overall experiment. From d 57 to slaughter, average DMI (10.33, 10.28, 10.57, 9.75, and 10.22 kg/steer daily for 0, 1,103, 2,205, 4,410, and 8,820 IU of vitamin A/kg of DM, respectively) was less (P0.02) by steers receiving 4,410 IU of supplemental vitamin A/kg of dietary DM than for steers in the other treatments. Furthermore, DMI was greater (P = 0.06) for steers receiving 2,205 IU of supplemental vitamin A/kg of dietary DM than for steers receiving 8,820 IU of supplemental vitamin A/kg of DM. Marbling score, HCW, LM area, and 12th-rib fat thickness did not differ (P0.10) among treatments. Similarly, the percentage of carcasses gradingor=USDA Choice (62.6, 52.8, 64.0, 58.4, and 58.4% for 0, 1,103, 2,205, 4,410, and 8,820 IU of vitamin A/kg of DM, respectively), Select, oror=Standard did not differ (P0.10) among treatments. Except for d 56 (P = 0.050; r = 0.18 for liver retinol), no correlations (P0.10) between marbling score and any plasma or liver tissue retinol or alpha-tocopherol concentrations or vitamin A intake were found, and no differences (P0.10) in lipogenic enzyme activity were detected among treatments. Taken together with previous and concurrent research, results of this experiment suggest that vitamin A supplementation at a concentration up to twice the NRC recommendation has little effect on performance, marbling, or lipogenic enzyme activity in adipose tissue samples in yearling feedlot steers, and that 2,205 IU of supplemental vitamin A/kg of DM (20,000 IU/steer daily) or less is adequate to meet the vitamin A requirements of finishing beef cattle.

A total of 432 crossbred yearling steers (395 kg +/- 6.35) were used in a randomized block experiment to study the effects of rumen degradable intake protein (DIP) and rumen undegradable intake protein (UIP) concentration on feedlot performance and carcass merit. The 6 dietary treatments used for this study included 1) a 10.5% CP diet with 5.1% UIP and 5.4% DIP (DIP5); 2) an 11.5% CP diet with 5.1% UIP and 6.4% DIP (DIP6); 3) a 12.5% CP diet with 5.1% UIP and 7.4% DIP (DIP7); 4) a 13.5% CP diet with 5.1% UIP and 8.4% DIP (DIP8); 5) a 14.5% CP diet with 5.1% UIP and 9.4% DIP (DIP9); and 6) a 14.5% CP diet with 6.1% UIP and 8.4% DIP with the additional UIP provided by corn gluten meal. There was a linear increase in final BW and ADG and a trend for a linear increase in DMI associated with increasing DIP concentration within the 5.1% UIP treatments. Feed efficiency and NE recovered from the diet were not influenced by dietary DIP concentration. As dietary DIP concentration increased, carcass fat depth and average yield grade increased linearly and the percentage of yield grade 1 and 2 carcasses decreased linearly. Dietary UIP treatment had no effect on final BW, ADG, DMI, G:F, and calculated NE recovery. For the 14.5% CP diets, marbling score tended to be reduced for steers fed 6.1% UIP as compared with 5.1% UIP. The remaining carcass traits were not affected by dietary UIP. The results of this study show that the DIP requirement in the finishing diet for heavy yearling steers fed steam-flaked corn is greater than 7.4% of dietary DM but likely is not more than 8.4% of dietary DM when dietary UIP is approximately 5.1% of dietary DM. Increasing UIP above 5.1% of dietary DM did not improve feedlot performance or HCW. Expressed on a CP basis, it appears as though the requirement for CP for heavy yearling steers fed steam-flaked corn-based finishing diets is 13.5% of DM, with approximately 62% of CP from DIP.

Four hundred thirty-two crossbred yearling steers (339 kg +/- 4.8) were used to investigate the effects of water quality and dietary potassium concentration and source on feedlot performance and carcass merit. The study was conducted using a 2 x 3 factorial treatment arrangement. Factors evaluated included 2 water sources: 1) a blend of reverse osmosis and well water (RO; 608 +/- 164 mg/L of SO(4)) and 2) 100% well water with SO(4) concentration of 1,933 +/- 53 mg/L and 3 dietary K treatments. Potassium treatments included 0.75% K with supplemental K from potassium chloride (0.75% K-KCl), 0.75% K with supplemental K from potassium carbonate (0.75% K-K(2)CO(3)), and 1.0% K with supplemental K from potassium carbonate (1.0% K-K(2)CO(3)). Interactions between water quality and dietary treatments were not significant. Dry matter intake tended (P = 0.10) to be greater for steers consuming RO water compared with well water and was not affected by dietary treatment. Feed efficiency (P = 0.04) and NE(g) recovery (P = 0.04) were greater for 1.0% K-K(2)CO(3) compared with 0.75% K-KCl but were not affected by water quality. Final BW was heavier (P0.001) and ADG was greater (P = 0.04) for RO water compared with well water but were not affected by diet. Carcasses from steers that consumed RO water tended (P = 0.08) to be heavier than carcasses from steers consuming well water. Dietary treatment did not affect HCW (P = 0.52). Yield grade calculated from carcass measurements was not affected by dietary treatment or water quality. Carcasses from steers consuming well water had greater (P = 0.04) marbling scores than RO water. These data demonstrate that steers consuming RO water achieved improved feedlot performance. Steers fed 1.0% K-K(2)CO(3) were more efficient and demonstrated improved energy recovery compared with steers fed 0.75% K-KCl. Improved efficiency and energy recovery may be related to a reduction (P = 0.06) in the liver abscess rate for steers consuming 1.0% K-K(2)CO(3). Dietary cation-anion balance was positively related to ADG (P0.01) and NE(g) (P = 0.03) recovery but negatively related to marbling score (P = 0.04).

Nonpregnant Hereford cows (n = 70) were used to determine the effect of nutrient intake and body condition on reproductive and thyroid function. Body condition scores (BCS; 1 = emaciated; 9 = obese) of cows averaged 5.0 +/- .2 on July 1, and cows were fed for 4 mo either to lose weight and BCS (thin; n = 22), to maintain weight and BCS (moderate; n = 24), or to gain weight and BCS (fat; n = 24). After November 1, cows received a complete ration to maintain weight and BCS. Cows were slaughtered in December (six thin, eight moderate, and eight fat cows) or the subsequent March (16 cows per group). Before slaughter, cows were given two injections of prostaglandin F2 alpha (PGF) 11 d apart. Six days after the second PGF injection, cows were simultaneously treated with 100 micrograms of gonadotropin releasing hormone (GnRH; i.m.) and 100 micrograms of thyrotropin releasing hormone (TRH; i.v.) and serum samples were obtained. The BCS of cows at slaughter (8 d after PGF) averaged 3.4, 5.3, and 7.1 (P less than .01) and carcass energy content averaged 243, 432, and 714 Mcal (P less than .01) for thin, moderate, and fat cows, respectively. Wet ovarian (P less than .001) and corpora lutea (P less than .01) weights were heavier for fat cows. Content of LH in the pituitary gland and concentrations of thyroxine (T4) in serum after GnRH/TRH were not influenced by nutrient intake or BCS. However, thin cows had greater concentrations (P less than .05) of LH in serum after GnRH/TRH than did moderate or fat cows. We conclude that nutrient intake and body energy reserves of beef cows influenced ovarian function and LH in serum after treatment with GnRH.

A feedlot growth performance experiment and 2 metabolism experiments were conducted to evaluate dietary roughage concentration and calcium magnesium carbonate in steers fed a high-grain diet. In Exp. 1, one hundred ninety-two crossbred yearling steers (320 +/- 10 kg of initial BW) were fed diets based on steam-flaked corn with 0, 0.75, or 1.5% CaMg(CO(3))(2). There were no effects (Por = 0.13) on ADG, DMI, G:F, or total water intake due to CaMg(CO(3))(2). In Exp. 2, five ruminally and duodenally fistulated steers (263 +/- 9 kg of initial BW) were used in a 5 x 5 Latin square design, with 5 dietary treatments arranged in a 2 x 2 + 1 factorial: 1) 3.8% dietary roughage and no CaMg(CO(3))(2); 2) 7.6% dietary roughage and no CaMg(CO(3))(2); 3) 11.4% dietary roughage and no CaMg(CO(3))(2); 4) 3.8% dietary roughage and 1.5% CaMg(CO(3))(2); and 5) 7.6% dietary roughage and 1.5% CaMg(CO(3))(2). Water consumption was less (quadratic, P = 0.003) when 7.6% dietary roughage was fed compared with 3.8 or 11.4% dietary roughage. Intake of DM was not affected (Por = 0.16) by dietary roughage or by CaMg(CO(3))(2). Poststomach and total tract starch digestion decreased (linear, P0.01) as dietary roughage increased. Ruminal pH tended (P = 0.08) to increase as dietary roughage increased but was not affected (P = 0.60) by CaMg(CO(3))(2). In Exp. 3, DMI and ruminal pH were continuously monitored in a 6 x 6 Latin square design using 6 ruminally and duodenally fistulated Holstein steers (229 +/- 10 kg of initial BW). A 3 x 2 factorial treatment structure was utilized, with factors consisting of dietary roughage concentration (4.5, 9.0, or 13.5%) and CaMg(CO(3))(2) inclusion (0 or 1.0%) to replace MgO and partially replace lime-stone. A dietary roughage x CaMg(CO(3))(2) interaction (P = 0.01) occurred as steers consuming 13.5% roughage, 1.0% CaMg(CO(3))(2) had greater DMI per meal than those consuming 4.5% dietary roughage, no CaMg(CO(3))(2) and 9.0% dietary roughage, 1.0% CaMg(CO(3))(2). Steers consuming 13.5% dietary roughage, 1.0% CaMg(CO(3))(2) and 9.0% dietary roughage, no CaMg(CO(3))(2) had greater meal length (min/meal; P = 0.01) than steers consuming 4.5% dietary roughage, no CaMg(CO(3))(2). Total tract OM digestibility decreased linearly (P = 0.01), and ruminal pH increased linearly (P = 0.01) with increasing dietary roughage concentration. Inclusion of CaMg(CO(3))(2) can replace limestone and MgO but did not produce ruminal pH responses similar to those observed by increasing dietary roughage in high-concentrate diets.

First results are presented of the processing of one of the Seismic lines of the Swiss National Program to study the deep geological structure of the Swiss Alps, located in the Anniviers valley (Val d'Anniviers-Valais). The rough topography of the study area gives rise to a crooked line geometry allowing analysis of lateral dips across the common mid-point (CMP) swath corresponding to a pseudo-3D study. The coherency of the Seismic reflections has been improved by accounting for the lateral dips and applying a correction before performing the CMP stack. The main E-W dip found by the Seismic pseudo-3D investigation confirms the surface geological survey. Preliminary geological interpretation suggests large-scale recumbent folding at depths between 10 and 20 km.

Previous studies have demonstrated that opioid substances are often inhibitors of the gamma-aminobutyric acid (GABA) transmitter system in the hippocampal formation, and that GABA-mediated inhibition is a potent modulator of synaptic plasticity. Field excitatory postsynaptic potentials were recorded from the CA1 region of rat hippocampal slices in response to stimulation of the Schaffer collateral fibers to monitor the effects of acute opioid exposure on the induction of long-term depression (LTD) at excitatory synapses in the stratum radiatum. Exogenous application of a selective mu-opioid agonist resulted in a greater than 2-fold enhancement of LTD, whereas kappa- and delta-agonists did not significantly affect LTD magnitude. Costimulation of the opioid peptide-containing stratum lacunosum-moleculare during LTD induction also resulted in a facilitation of LTD in the stratum radiatum, an effect prevented by prior administration of an opioid antagonist. These results suggest that both exogenously applied and endogenously released opioids can act to facilitate LTD of the Schaffer collateral input to CA1 pyramidal neurons.

Long-term depression (LTD) now occupies a major place in theories of the cellular basis of learning and memory and other nervous system phenomena involving persistent changes in synaptic responsiveness. LTD can be induced using a variety of stimulation paradigms. Homosynaptic LTD in this review refers to a depression of basal responses that is restricted to the pathway that has been stimulated by a low-frequency (1 Hz) stimulus train. Despite the intensive interest in LTD, there has been controversy about the ease with which LTD can be induced and reports range from no success to routine success. There has been much less controversy about a related form of response depression now called "depotentiation" which shares many similarities with LTD. Depotentiation is the response reduction that affects, not the basal responses affected by LTD, but responses that have been increased by the process of long-term potentiation (LTP). LTD and depotentiation can be induced by similar stimulation and have many biochemical properties in common, but it has not been clear whether or not they represent the same phenomenon, in part because it often occurs that the same preparation that does not undergo LTD readily expresses depotentiation. We review work that indicates that the major differences between LTD and depotentiation involve age-dependence, the need for priming stimulation and sensitivity to GABA receptor antagonists. We present a hypothetical model that can reconcile the apparent disparities between LTD and depotentiation.

Muscarinic, cholinergic inputs, largely from the medial septum, have pronounced effects on hippocampal cell excitability. A major effect of synaptically released ACh is block of the slow Ca(2+)-dependent potassium current, called IAHP. Protein kinase C exists in the hippocampus in high concentrations, its activation blocks IAHP, and it has been suggested as a mediator of the muscarinic-receptor-(mAChR)-mediated actions. Using conditions that produce a stable postspike afterhyperpolarizing current (IAHP) in whole-cell recordings from CA1 hippocampal pyramidal neurons in the slice preparation, we have investigated the role of PKC in the cholinergic inhibition of IAHP mediated by mACHRs. Bath application of the general kinase inhibitor, H7, had no effect on inhibition of IAHP by carbachol, although H7 dramatically reduced inhibition of IAHP by the phorbol ester, phorbol-12, 13-diacetate (PDA). Another muscarinic response thought to be mediated by PKC-inhibition of GABAB-mediated hyperpolarization-was reduced by extracellular H7 treatment, suggesting that the coupling between mAChRs and protein kinase activity was maintained in whole-cell recordings. We also discovered that PDA does not mediate its effects on IAHP directly. Intracellular perfusion of high concentrations of H7 (10 mM) or the specific PKC inhibitor, PKCI(19-31) (1 mM), did not prevent inhibition of IAHP by PDA. These results are consistent with an indirect, presynaptic action of phorbol esters on IAHP, possibly mediated through enhanced release of neurotransmitter from surrounding cells.

Nonpregnant Hereford cows (n = 70) were used to determine the effect of nutrient intake and body condition on reproductive and thyroid function. Body condition scores (BCS; 1 = emaciated; 9 = obese) of cows averaged 5.0 +/- .2 on July 1, and cows were fed for 4 mo either to lose weight and BCS (thin; n = 22), to maintain weight and BCS (moderate; n = 24), or to gain weight and BCS (fat; n = 24). After November 1, cows received a complete ration to maintain weight and BCS. Cows were slaughtered in December (six thin, eight moderate, and eight fat cows) or the subsequent March (16 cows per group). Before slaughter, cows were given two injections of prostaglandin F2 alpha (PGF) 11 d apart. Six days after the second PGF injection, cows were simultaneously treated with 100 micrograms of gonadotropin releasing hormone (GnRH; i.m.) and 100 micrograms of thyrotropin releasing hormone (TRH; i.v.) and serum samples were obtained. The BCS of cows at slaughter (8 d after PGF) averaged 3.4, 5.3, and 7.1 (P less than .01) and carcass energy content averaged 243, 432, and 714 Mcal (P less than .01) for thin, moderate, and fat cows, respectively. Wet ovarian (P less than .001) and corpora lutea (P less than .01) weights were heavier for fat cows. Content of LH in the pituitary gland and concentrations of thyroxine (T4) in serum after GnRH/TRH were not influenced by nutrient intake or BCS. However, thin cows had greater concentrations (P less than .05) of LH in serum after GnRH/TRH than did moderate or fat cows. We conclude that nutrient intake and body energy reserves of beef cows influenced ovarian function and LH in serum after treatment with GnRH.

A measurement of the electron spectrum from the thermal neutron fission of U/sup 235/ is described. From this spectrum the antineutrino spectrum is calculated, and on the basis of the two-component theory of the antineutrino a predicted average cross section for the absorption of antineutrinos by protons is (6.1 the J-57 engin 1) x 10/sup -43/ cm/sup 2/fission. This agrees with the measured cross section of (8.7 the J-57 engin 1.5) x 10/sup -43/ cm/sup 2/ fission. The four-component theory of the antineutrino would have predicted (5.05 the J-57 engin 0.5) x 10/sup -43/ cm/sup 2/fission. (auth)

Summary. The geomagnetic palaeosecular variation has been studied in terms of two current loops which change their positions and orientations with time. The results broadly agree with the observed data. Comparison with the existing models is made.

The kinetics of the silicon/hydrogen low-pressure discharge system have been measured using a flow technique and mass spectrometry. Results show that at long residence times the system operates under a partial chemical equilibrium even though it is not at thermodynamic equilibrium. The present work indicates that the decisive parameter controlling the structural properties of the deposit (i.e., the formation of either amorphous or microcrystalline silicon) is the departure of the system from the partial chemical equilibrium.

The diffusion coefficients of He, Ne, and Ar in various samples of GeO2 and approximate values for the corresponding solubility coefficients were obtained from nonisothermal and isothermal desorption experiments. The data show trends similar to those obtained on fused SiO2 , and are interpreted by assuming that the glasses contain many interstices of different critical dimensions and a variety of diffusion paths corresponding to a range of activation energies. Some annealed and partially devitrified samples were studied and the activation energies of diffusion were found to be relatively high. In a few cases, the measurements were extended into and above the glass transition range (∼570°) ; the resulting activation energy and the preexponential factor of the Arrhenius equation for the diffusion coefficient were markedly increased, indicating that the diffusion mechanism is probably drastically changed.

Normal and reversed remanent magnetization has been found in Plio-Pleistocene basalts from Bulgaria. Ore microscope observations show that the magnetic mineral is a homogeneous ‘titanomagnetite’: electron microprobe studies show that it contains a high proportion of Ti. Comparison of thermomagnetic measurements with the Curie points expected for stoichiometric titanomagnetites with the analysed chemical composition suggest that the titanomagnetites must be slightly oxidized, i.e. be slightly cation deficient.

A measurement of the electron spectrum from the thermal neutron fission of U/sup 235/ is described. From this spectrum the antineutrino spectrum is calculated, and on the basis of the two-component theory of the antineutrino a predicted average cross section for the absorption of antineutrinos by protons is (6.1 the J-57 engin 1) x 10/sup -43/ cm/sup 2/fission. This agrees with the measured cross section of (8.7 the J-57 engin 1.5) x 10/sup -43/ cm/sup 2/ fission. The four-component theory of the antineutrino would have predicted (5.05 the J-57 engin 0.5) x 10/sup -43/ cm/sup 2/fission. (auth)

A disrupted ophiolitic complex of Cretaceous age from the Romeral fault zone in the southwestern Colombian Andes occurs in the La Tetilla area near Popayan. It represents a peculiar association of low-Ti and high-Ti tholeiitic basalts among the ophiolitic complexes from the Romeral Zone. It includes: (1) A main sequence (with incipient metamorphism under prehnite-pumpellyite to greenschist facies conditions) con- sisting in ascending order of cumulus wehrlite and gabbro, massive gabbro, and basaltic and doleritic lavas and breccias. The basalts are characterized by the crystallization of clinopyroxene prior to plagioclase (cpx-phyric basalt group) and have a primitive low-Ti tholeiite composition (Mg numbers between 70.6 and 65.4). The clinopyroxene chemistry is consistent with this magmatic affinity. The plutonic rocks can be related to a similar low-Ti tholeiitic magma. (2) A sequence of pervasively metamorphosed basalts (with greenschist facies metamorphism of oceanic type) structurally underlies the main sequence. Basalts are characterized by the order of crystallization: ol-plag-cpx (plag-phyric basalt group) and high-Ti tholeiitic chemistry. (3) A sequence of foliated metabasalts (with greenschist to amphibolite transition metamorphism) including low-Ti picritic and high-Ti tholeiitic basalts. Different tectonic settings can be inferred from the petrological features of the recognized magmatic sequences, but constraints by the regional setting are still insufficient to permit a unique interpretation. The one proposed tentatively is that the low-Ti basalts and the plutonics, which are probably cogenetic, formed in an intraoceanic arc at an early stage of develop ment, similar to many supra-subduction zone ophiolites. The high-Ti basalts could have been associated with the former sequence prior to the tectonic emplacement, and could represent remnants of an ocean island volcanism.

Seventy-two mature, nonpregnant, nonlactating Hereford cows (400 kg) were utilized in a comparative slaughter trial to investigate the effects of carcass composition on the metabolizable energy (ME) required for maintenance in winter. Body condition score (CS), live weight (LW) and weight:height ratio (WTHT) were evaluated and compared as estimators of carcass composition in cows. Cows ranged in LW, CS and WTHT from 275 to 595 kg, 2.0 to 8.0 units and 2.29 to 4.62 kg/cm, respectively. Live weight, CS and WTHT predicted total carcass energy (TMCAL, r2 = .81, .85 and .83), carcass fat (FAT, r2 = .78, .82 and .80), carcass protein (PRO, r2 = .71, .74 and .70) and carcass water (WAT, r2 = .78, .71 and .77) with similar accuracy. When composition was expressed on a per unit weight basis, CS was superior to LW and WTHT as predictors of TMCAL/hot carcass weight, TMCAL/LW and FAT/hot carcass weight (r2 = .82, .60 and .64; .83, .58 and .62; and .82, .64 and .68, respectively). Forty-seven cows were individually fed a complete diet (2.50 Mcal ME/dry matter) in drylot for 114 d in yr 1 and 115 d in yr 2. Daily feed intakes were adjusted each week to maintain constant LW throughout the winter. Data were analyzed by fitting the model: ME intake = k-1 (carcass energy change) + f(CS)LW.75, where k = efficiency of ME use for carcass energy change and f(CS) = function of CS. Year as a class variable and the expression .1028 + .0234(CS) - .0025(CS)2 accounted for 41% of the variation in Mcal ME for maintenance/LW.75. Condition score was more closely related to carcass composition in mature cows than was LW or WTHT and cows in either a thin (CS = 3) condition or a fat (CS = 7) condition required less (4.4% and 8.9%) Mcal ME/LW.75 for maintenance than cows in moderate (CS = 5) condition.

Despite the recent advancement in the social robotic field, important limitations restrain its progress and delay the application of robots in everyday scenarios. In the present paper, we propose to develop computational models inspired by our knowledge of human infants’ social adaptive abilities. We believe this may provide solutions at an architectural level to overcome the limits of current systems. Specifically, we present the functional advantages that adaptive Theory of Mind (ToM) systems would support in robotics (i.e., mentalizing for belief understanding, proactivity and preparation, active perception and learning) and contextualize them in practical applications. We review current computational models mainly based on the simulation and teleological theories, and robotic implementations to identify the limitations of ToM functions in current robotic architectures and suggest a possible future developmental pathway. Finally, we propose future studies to create innovative computational models integrating the properties of the simulation and teleological approaches for an improved adaptive ToM ability in robots with the aim of enhancing human-robot interactions and permitting the application of robots in unexplored environments, such as disasters and construction sites. To achieve this goal, we suggest directing future research towards the modern cross-talk between the fields of robotics and developmental psychology.