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The current study draws on the upper echelons theory to examine the nature of the relationship between top management team (TMT) tenure and a firm's level of entrepreneurial orientation (EO). We find evidence of an inverted-U relationship between TMT tenure and EO using data from firms across three industries with varied industry dynamics. We further introduce a contingency element by demonstrating that TMT industry background heterogeneity moderates the relationship between TMT tenure and EO, where the inverted U-shaped relationship will be more pronounced when the heterogeneity is low and will flatten when the heterogeneity is high. The findings demonstrate the complexity CEOs and governing bodies face while shaping a diverse TMT that can affect EO. [ABSTRACT FROM AUTHOR]

Purpose Mergers in higher education seem to be more common as academic institutions work to control costs and avoid program duplications in challenging economic times and adopt the more common cost saving measures often espoused from business mergers. The purpose of this paper is to highlight successes from a complementarity-based merger of two institutions in the University System of Georgia (USG) and present results over time.Design/methodology/approach A case study methodology was employed to explain why a particular merger resulted in greater growth compared to other system-wide academic mergers. This research focuses on a single merger of two institutions in Georgia, one of seven such mergers in the USG institutions to date, involving Gainesville State College and North Georgia College and State University to become the University of North Georgia. Observations are made and complimented by secondary data to rank growth among the seven USG consolidations.Findings The case findings highlight the success from the complementarity of these institutions. While the two were unique institutions, the success of the merger was linked to the underlying complementarity issues.Originality/value Using the strategic issues inherent in mergers from the business literature, the merger of the two institutions is profiled and discussion and recommendations are provided along with areas for future research. [ABSTRACT FROM AUTHOR]

The current research investigates how entrepreneurial orientation changes during a chief executive officer ( CEO)'s tenure in family and nonfamily firms. Based on secondary data collected from 210 firms representing five industries, the results show an inverse U-shaped relationship between CEO tenure and entrepreneurial orientation, consistent with the executive life cycle literature. Moreover, in family firms the shape of the inverse U is less pronounced and the level of entrepreneurial orientation peaks considerably later in the CEO's tenure when compared with nonfamily firms. [ABSTRACT FROM AUTHOR]

Grazing Neotyphodium coenophialum- infected forages results in a variety of reduced animal performance parameters, collectively known as "fescue toxicosis." The initial, limited evaluations of hepatic mechanisms affected by fescue toxicosis have used transcriptomic expression profiling of experimental phenotypes developed by short-term feeding of concentrated ergot alkaloids or fescue seeds to rodents and steers. To assess the effects of fescue toxicosis in growing cattle using a commercially relevant phenotype, we induced fescue toxicosis in beef steers by summer-long grazing (89 to 105 d) of a single high toxic endophyte-infected tall fescue pasture (HE; 0.746 µg/g ergot alkaloids; 5.7 ha; n = 10; BW = 267 ± 14.5 kg) vs. a low toxic endophyte tall fescue- mixed pasture (LE; 0.023 µg/g ergot alkaloids; 5.7 ha; n = 9; BW = 266 ± 10.9 kg). High toxic endophyte tall fescue-mixed pasture steers had decreased BW (313 vs. 338 kg) and an increased potential for hepatic gluconeogenesis from AA-derived carbons. To gain a greater perspective into fescue toxicosis-induced hepatic metabolism and identify candidate regulatory mechanisms, the goal of the current research was to examine liver samples for changes in gene (mRNA) expression profiles using a Bovine Affymetrix microarray and selected reverse-transcription PCR and immunoblot analyses. The expression (false discovery rate < 10%; P < 0.01) of 147 genes was increased (7 to 268%) and that of 227 was decreased (4 to 87%) in livers of HE vs. LE steers. The top (1) functional gene category was cell-mediated immune response (33 genes; P ≤ 0.012), (2) canonical cell signaling pathway was primary immunodeficiency signaling (8 genes; P ≤ 0.0003), and (3) canonical metabolic pathways were oxidative phosphorylation (5 genes; P ≤ 0.016) and purine metabolism (8 genes; P ≤ 0.029). High toxic endophyte tall fescue-mixed pasture steers had increased (P ≤ 0.022) expression of genes critical for increased (1) Pro (PYCR1) and Ser (PSPH) synthesis, (2) shunting of AA carbons into pyruvate (ALT2) and ATP synthesis (NDUFC1, NDUFV2, UCRC, COX4, ATP5D, and ATP5F1), and (3) mitochondrial mass (COX4). Targeted reverse-transcribed PCR or immunoblot assays corroborated (P ≤ 0.035) these latter microarray findings for PYCR1, PSPH, ALT2, PEPCK, and COX4. Moreover, network analysis identified glucocorticoid receptor-mediated signaling as the most probable mechanism to coordinate the above findings. These results greatly extend our knowledge of the consequences of summer-long grazing of endophyte-infected tall fescue to the hepatic metabolism of growing steers. [ABSTRACT FROM AUTHOR]

Aged beef cows (= 8 yr of age) produce calves with lower birth and weaning weights. In mammals, aging is associated with reduced hepatic expression of glutamine synthetase (GS) and alanine transaminase (ALT), thus impaired hepatic Gln-Glu cycle function. To determine if the relative protein content of GS, ALT, aspartate transaminase (AST), glutamate transporters (EAAC1, GLT-1), and their regulating protein (GTRAP3-18) differed in biopsied liver tissue of (a) aged vs. young (3 to 4 yr old) nonlactating, nongestating Angus cows (Exp. 1 and 2) and (b) aged mixed-breed cows with and without COMPUDOSE (17β-estradiol) ear implants (Exp. 3), Western blot analyses were performed. In Exp. 1, 12 young (3.62 ± 0.01 yr) and 13 aged (10.08 ± 0.42 yr) cows grazed the same mixed forage for 42 d (August-October). In Exp. 2, 12 young (3.36 ± 0.01 yr) and 12 aged (10.38 ± 0.47 yr) cows were individually fed (1.03% of BW) a corn-silage-based diet to maintain BW for 20 d. For both Exp. 1 and 2, the effect of cow age was assessed by ANOVA using the MIXED procedure of SAS. Cow BW did not change (P = 0.17). Hepatic ALT (78% and 61%) and GS (52% and 71%) protein content (Exp. 1 and 2, respectively) was decreased (P = 0.01), whereas GTRAP3-18 (an inhibitor of EAAC1 activity) increased (P = 0.01; 170% and 136%) and AST, GLT-1, and EAAC1 contents did not differ (P = 0.17) in aged vs. young cows. In Exp. 2, free concentrations (nmol/g) of Glu, Ala, Gln, Arg, and Orn in liver homogenates were determined. Aged cows tended to have less (P = 0.10) free Gln (15.0%) than young cows, whereas other AA concentrations did not differ (P = 0.26). In Exp. 3, 14 aged (> 10 yr) cows were randomly allotted (n = 7) to sham or COMPUDOSE (25.7 mg of 17β-estradiol) implant treatment (TRT), and had ad libitum access to alfalfa hay for 28 d. Blood and liver biopsies were collected 14 and 28 d after implant treatment. Treatment, time after implant (DAY), and TRT × DAY effects were assessed by ANOVA using the MIXED procedure of SAS. Cow BW was not affected (P = 0.96). Implant increased (P = 0.02) total plasma estradiol by 220% (5.07 vs. 1.58 pg/mL) and GS protein by 300%, whereas the relative content of other proteins was not altered (P = 0.16). We conclude that hepatic expression of ALT and GS are reduced in aged vs. young cows, and administration of 17β-estradiol to aged cows increases plasma estradiol and hepatic GS, but not that of other proteins that support hepatic Glu metabolism. [ABSTRACT FROM AUTHOR]

Selenium (Se) is an important trace mineral that, due to deficiencies in the soil in many parts of the USA, must be supplemented directly to the diet of foraging cattle. Both organic and inorganic forms of dietary Se supplements are available and commonly used, and it is known that Se form affects tissue assimilation, bioavailability, and physiological responses. However, little is known about the effects of form of dietary Se supplements on gene expression profiles, which ostensibly account for Se form-dependent physiological processes. To determine if hepatic transcriptomes of growing beef (Angus-cross) heifers (0.5 kg gain/day) was altered by form of dietary supplemental Se, none (Control), or 3 mg Se/day as inorganic Se (ISe, sodium selenite), organic (OSe, Sel-Plex®), or a blend of ISe and OSe (1.5 mg:1.5 mg, Mix) Se was fed for 168 days, and the RNA expression profiles from biopsied liver tissues was compared by microarray analysis. The relative abundance of 139 RNA transcripts was affected by Se treatment, with 86 of these with complete gene annotations. Statistical and bioinformatic analysis of the annotated RNA transcripts revealed clear differences among the four Se treatment groups in their hepatic expression profiles, including (1) solely and commonly affected transcripts; (2) Control and OSe profiles being more similar than Mix and ISe treatments; (3) distinct OSe-, Mix-, and ISe-Se treatment-induced 'phenotypes' that possessed both common and unique predicted physiological capacities; and (4) expression of three microRNAs were uniquely sensitive to OSe, ISe, or Mix treatments, including increased capacity for redox potential induced by OSe and Mix Se treatments resulting from decreased expression of MiR2300b messenger RNA. These findings indicate that the form of supplemental dietary Se consumed by cattle will affect the composition of liver transcriptomes resulting, presumably, in different physiological capacities. [ABSTRACT FROM AUTHOR]

As part of a 2-yr study documenting the physiologic impact of grazing endophyte-infected tall fescue on growing cattle, 2 experiments were conducted to characterize and evaluate effects of grazing 2 levels of toxic endophyte-infected tall fescue pastures on vascular contractility and serotonin receptors. Experiment 1 examined vasoconstrictive activities of 5-hydroxytryptamine (5HT), α-methylserotonin (ME5HT; a 5HT2 receptor agonist), D-lysergic acid (LSA), and ergovaline (ERV) on lateral saphenous veins collected from steers immediately removed from a high-endophyte-infected tall fescue pasture (HE) or a low-endophyte-infected mixed-grass (LE) pasture. Using the same pastures, Exp. 2 evaluated effects of grazing 2 levels of toxic endophyte-infected tall fescue on vasoconstrictive activities of (±)-1-(2 ,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI), BW 723C86 (BW7), CGS-12066A (CGS), and 5-carboxamidotryptamine hemiethanolate maleate (5CT), agonists for 5HT2A, 2B, 5HT1B, and 5HT7 receptors, respectively. One-half of the steers in Exp. 2 were slaughtered immediately after removal from pasture, and the other one-half were fed finishing diets for >91 d before slaughter. For Exp. 1, maximal contractile intensities were greater (P < 0.05) for steers grazing LE pastures than HE pastures for 5HT (73.3 vs. 48.9 ± 2.1%), ME5HT (52.7 vs. 24.9 ± 1.5%), and ERV (65.7 vs. 49.1 ± 2.6%). Onset of contractile response did not differ for 5HT (P = 0.26) and ERV (P = 0.93), but onset of ME5HT contraction was not initiated (P < 0.05) in HE steers until 10-4 compared with 10-5 M in LE-grazing steers. For Exp. 2, maximal contractile intensities achieved with DOI were 35% less (P < 0.05), whereas those achieved with 5CT were 37% greater (P < 0.05), in steers grazing HE pastures. Contractile response to CGS did not differ between pasture groups, and there was an absence of contractile response to BW7 in both groups. There were no differences between endophyte content in contractile responses after animals were finished for >91 d. Experiment 1 demonstrated that grazing of HE pastures for 89 to 105 d induces functional alterations in blood vessels, as evidenced by reduced contractile capacity and altered serotonergic receptor activity. Experiment 2 demonstrated that grazing HE pastures alters vascular responses, which may be mediated through altered serotonin receptor activities, and these alterations may be ameliorated by the removal of ergot alkaloid exposure as demonstrated by the absence of differences in finished steers. [ABSTRACT FROM AUTHOR]

To determine the effect of metabolic acidosis on expression of L-Gln, b-Gill, and L-Asp metabolizing enzymes and transporters, the relative content of mRNA, protein, or mRNA and protein, of 6 enzymes and 5 transporters was determined by real-time reverse transcription-PCR and immunobiot analyses in homogenates of kidney, skeletal muscle, and liver of growing lambs fed a common diet supplemented with canola meal (control; n = 5) or HC1-treated canola meal (acidosis; n = 5). Acidotic sheep had a 790% greater (P = 0.050) expression of renal Na+-coupled neutral AA transporter 3 mRNA and a decreased expression of renal glutamine synthetase mRNA (47% reduction, P = 0.037) and protein (57% reduction, P = 0.015) than control sheep. No change in renal cytosolic phosphoenolpyruvate carboxykinase (protein and mRNA), glutaminase (mRNA), or L-Glu dehydrogenase (protein) was found. In skeletal muscle, acidotic sheep had 101% more (P = 0.026) aspartate transaminase protein than did control sheep, whereas no change in the content of 3 Na+-coupled neutral AA transporters (mRNA) or 2 high-affinity L-Glu transporter proteins was found. In liver, no change in the content of any assessed enzyme or transporter was found. Collectively, these findings suggest that tissue-level responses of sheep to metabolic acidosis are different than for nonruminants. More specifically, these results indicate the potential capacity for metabolism of L-Asp and L-Glu by skeletal muscle, and L-Gln absorption by kidneys, but no change in hepatic expression of L-Gln metabolism, elaborates previous metabolic studies by revealing molecular-level responses to metabolic acidosis in sheep. The reader is cautioned that the metabolic acidosis model employed in this study differs from the increased plasma lactateinduced metabolic acidosis commonly observed in ruminants fed a highly fermentable grain diet. [ABSTRACT FROM AUTHOR]

In mammals, the absorption of monosaccharides from small intestinal lumen involves at least 3 sugar transporters (SugT): sodium-dependent glucose transporter 1 (SGLT1; gene SLC5A1) transports glucose and galactose, whereas glucose transporter (GLUT) 5 (GLUT5; gene SLC2A5) transports fructose, across the apical membrane of enterocytes. In contrast, GLUT2 (gene SLC2A2) transports all of these sugars across basolateral and apical membranes. To compare the distribution patterns and sensitivity with nutritional regulation of these 3 SugT mRNA in beef cattle small intestinal tissue, 18 ruminally and abomasally catheterized Angus steers (BW ≈ 260 kg) were assigned to water (control), ruminal cornstarch (partially hydrolyzed by α-amylase; SH), or abomasal Sil infusion treatments (n = 6) and fed an alfalfa-cube-based diet at 1.3 x NEm requirement. The SH infusions amounted to 20% of ME intake. After 14- or 16-d of infusion, steers were killed; duodenal, jejunal, and ileal epithelia harvested; and total RNA extracted. The relative amount of SugT mRNA in epithelia was determined using real-time re- verse transcription-PCR quantification methods. Basal expression of GLUT2 and SGLT1 mRNA was greater (P < 0.09) by jejunal than by duodenal or ileal epithelia, whereas basal content of GLUT5 mRNA was greater (P < 0.02) by jejunal and duodenal than by ileal epithelia. The content of GLUT5 mRNA in small intestinal epithelia was not affected (P > 0.16) by either SH infusion treatment. In contrast, GLUT2 and SGLT1 mRNA content in the ileal epithelium was increased (P < 0.05) by 6.5- and 1.3-fold, respectively, after abomasal SH infusion. Duodenal SGLT1 mRNA content also was increased (P = 0.07) by 64% after ruminal SH infusion. These results demonstrate that the ileum of beef cattle small intestine adapts to an increased luminal supply of glucose by increasing SGLT1 and GLTUT2 mRNA content, whereas increased ruminal SH supply results in duodenal upregulation of SGLT1 mRNA content. These adaptive responses of GLUT2 and SGLT1 mRNA to abomasal or ruminal SH infusion suggest that beef cattle can adapt to increase their carbohydrate assimilation through small intestinal epitheha, assuming that altered SugT mRNA contents reflect the altered transport functional capacities. [ABSTRACT FROM AUTHOR]

It is well established that grazing Neotyphodium coenophialum-infected forages results in reduced BW gain and serum prolactin concentrations of cattle. The objective of this study was to determine the potential effects of toxic endophyte-infected tall fescue consumption on blood metabolites, carcass characteristics, and content of proteins critical for AA metabolism in the liver, kidney, and LM tissue of growing steers. Steers grazed a low toxic endophyte (LE; 0.023 µg/g ergot alkaloids) tall fescue-mixed grass pasture (n = 9; BW = 266 ± 10.9 kg; 5.7 ha) or a high toxic endophyte (HE; 0.746 µg/g of ergot alkaloids) tall fescue pasture (n = 10; BW = 267 ± 14.5 kg; 5.7 ha) from June 14 through at least September 11 (≥89 d). No difference was observed for BW (P < 0.10) for the overall 85-d growth period. Also, no differences were observed for ribeye area/100 kg of HCW (P> 0.91), backfat (P> 0.95), or backfat/100 kg of HCW (P> 0.67). However, ADG (P < 0.01), final BW (P < 0.05), HCW (P < 0.01), dressing percentage (P < 0.01), ribeye area (P < 0.01), whole liver wet weight (P < 0.01), and whole liver wet weight/100kg of end BW (P < 0.01) were greater for LE steers than HE steers. After 85 d of grazing, serum concentrations of alkaline phosphatase (P < 0.05), alanine aminotransferase (P < 0.01), aspartate arninotransferase (P < 0.03), cholesterol (P < 0.01), lactate dehydrogenase (P < 0.01), and prolactin (P < 0.01) were less for HE than LE steers. At slaughter, hepatic content of cytosolic phosphoenolpyruvate carboxykinase (P < 0.01) was greater in HE steers than LE steers. Hepatic content of aspartate aminotransferase (P < 0.01) also was greater, whereas renal and LM content were not (P ≥ 0.42). No differences (P ≥ 0.15) were observed for hepatic, renal, and LM content of alanine aminotransferase, glutamate dehydrogenase, glutamine synthetase, and 3 glutamate transport proteins. These data indicate that the HE steers displayed classic endophyte toxicity symptoms for growth arid blood variables, classic symptoms that were concomitant with novelly identified altered glucogenic capacity of the liver and decreases in carcass characteristics. [ABSTRACT FROM AUTHOR]

Although dietary supplementation of cationic AA (CAA), especially L-Lys, is known to be essential for optimal growth of beef cattle, the proteins responsible for absorption of CAA by bovine intestinal epithelia have not been described. Cationic AA transporter-1 (CAT-1) is a major intestinal CAA transporter, demonstrating a high-affinity (µM) transport activity for L-Lys in other mammals, and is widely expressed by small intestinal epithelia of nonruminants, but neither sequence nor expression pattern data exist for CAT-1 in cattle. Therefore, the goal of this research was to compare the relative expression (putative) of CAT-1 mRNA by duodenal, jejunal, or ileal small intestinal epithelia across and within commercially relevant beef cattle production and development stages. Twenty-four Angus steers were assigned randomly (n = 6) to i of 4 treatments (suckling, weanling, growing, and finishing) after all steers were born. Duodenal, jejunal, and ileal epithelia were scraped, and total RNA was extracted after the steers were killed at 32, 184, 248, or 423 d of age. Average daily gains of the steers did not differ (1.09 ± 0.05 kg/d) among stages, whereas the small intestinal length relative to BW decreased (P < 0.01) with steer development. Using standard reverse transcription-PCR cloning techniques, we generated a partial-length bovine CAT-1 complementary DNA (695 bp; GenBank accession no. DQ399522) from jejunal mRNA samples, which possessed 89 and 87% identities to pig and human CAT-1 orthologs, respectively. On the basis of this bovine-specific genetic data, a real-time PCR-based assay of reverse-transcribed mRNA was developed and used to measure relative changes in bovine CAT-1 mRNA abundance in intestinal epithelia as steers developed. The CAT-1 mRNA was expressed by the duodenum, jejunum, and ileum of all 4 production stages. In contrast to expression by duodenal or ileal epithelium, jejunal expression of CAT-1 mRNA by growing steers was greater (P = 0.005) than that by suckling, weanling, or finishing steers. In terms of the expression of CAT-1 mRNA within production stage, jejunal expression was greater (P = 0.002) than that by duodenum or ileum for growing steers. In contrast, no intestinal site difference was found for suckling, weanling, or finishing steers. These data indicate that previously reported Natindependent uptake of Lys by jejunal and ileal epithelia likely occurred by CAT-1, and that the potential capacity for CAT-1-mediated uptake of CAA for beef steers may be greatest for the "growing" phenotype. [ABSTRACT FROM AUTHOR]

Forty steer calves averaging 257 kg were allotted to a randomized complete block design experiment containing 10 animals per treatment. Four tall fescue pastures of 5.7 ha each were utilized during the 84-d grazing study. Each pasture treatment block contained 10 calves. Calves were fed a control supplement of 96.9% ground corn and 3.1% trace mineral salt in two pastures, or a sulfur supplement that contained 94.3% ground corn, 3.1% trace mineral salt, and 2.5% elemental sulfur in the remaining two pastures. Each supplement was fed at the rate of 0.45 kg/head daily. One-half of the calves in each pasture were injected with 15 mg selenium (Se) as sodium selenite initially and at 28-d intervals throughout the trial. The treatments were as follows: (1) control-no sulfur, no selenium; (2) selenium, no sulfur; (3) sulfur, no selenium and; (4) selenium plus sulfur. Calf weights were monitored and certain blood parameters measured every 28 d. Average plasma Se values were increased (P < 0.001) from 0.021 ppm in calves not receiving Se to 0.043 ppm in those receiving Se. Plasma urea nitrogen levels were not affected by Se administration, but were lowered (P <0.05) from 16.6 to 15.8 mg/100 mL by sulfur administration. All plasma amino acids measured, except methionine, phenylalanine, argi-nine, and citrulline, were cleared from the blood in response to Se supplementation as reflected by their lower concentrations when compared with other treatment groups. Overall average daily gains were not significantly (P > 0.10) increased by sulfur supplementation, but were increased (P < 0.05) from 0.33 kg/d in calves not receiving Se to 0.43 kg/d in those receiving Se injections. Significant interactions between fulfur and Se were not noted. [ABSTRACT FROM AUTHOR]

Although L-Lysine (Lys) is a dietarily-essential amino acid (AA) for cattle fed a high corn diet, proteins responsible for absorption of Lys by cattle have not been described. CAT1 is a major intestinal transporter of cationic AA. CAT1 demonstrates a high-affinity (μM) System y+ activity that differs from b0,+, y+L, and B0,+ cationic AA transporter systems due to its independence of Na+ (-Na+) and/or insensitivity to neutral AA. This project was conducted to determine if Madin-Darby Bovine Kidney (MDBK) cells and steer hepatocytes express CAT1 activity and/or mRNA. Putative System y+ activity was assessed in wells (n = 8-12) of 2-d cultured MDBK cells (250,000/2 cm2 well) by characterizing the -Na+ uptake (pmol/mg protein) of Lys (10 μM; [H3]Lys, radiotracer) in the presence and absence of 2 mM L-Arg or L-Leu. System y+ Lys uptake accounted (P < 0.001) for 50% of total -Na+ Lys uptake, as did Systems B0,+ and/or y+L. Km determination for -Na+ Lys in the presence of 5 mM L-Leu was 250 μM, consistent with CAT1 activity. RT-PCR of total RNA extracted from MDBK cells (and bovine kidney, and ileal epithelium), using the full-length pig CAT1 as a template, produced a single cDNA product of about 700 bp. Sequencing of the MDBK and kidney products revealed a 695-bp cDNA that possessed 89, 87, 99% homology with corresponding regions of the pig, human, and predicted bovine CAT1 mRNA, respectively. The expression of System y+ activity and CAT1 mRNA next was evaluated in wells (4-6) of 2-d cultured hepatocytes (200,000/2 cm2 well) isolated (collagenase perfusion) from the caudal lobe of 30-d old Angus steer livers (n = 4), using transport and RT-PCR parameters identical to those used for MDBK cells. Systems y+, b0,+, and y+L accounted (P < 0.034) for 19, 34, and 47% of -Na+ Lys uptake, respectively, and RT-PCR yielded a product of about 700 bp. These results demonstrate that MDBK cells and steer hepatocytes express CAT1 activity and mRNA and indicate their usefulness to study bovine CAT1 function and expression. [ABSTRACT FROM AUTHOR]