Assessing the size and growth of the US wetland and stream compensatory mitigation industry.

Interest has focused on quantifying the size and scope of environmental markets, particularly those that offset ecosystem impacts or restore natural infrastructure to improve habitat or promote clean air and water. In this paper, we focus on the US wetland and stream compensatory mitigation market, asking: what types of firms make up the mitigation "industry"? What are the economic impacts-i.e., the "size"-of the mitigation industry? How has this industry changed over time? We present the results of a national survey of mitigation firms and construct an input-output model of the industry's economic impacts and employment. We also develop a comparative, 2014 model of the industry using data from a previous study of the broader, ecological restoration economy. Our findings suggest that the (2019, pre-COVID) mitigation industry collects annual revenues (direct economic impacts) in excess of $3.5 billion, which, along with additional indirect (supply chain) and induced (spillover) economic impacts, combine to over $9.6 billion in total output and support over 53,000 total jobs. We estimate 2014-2019 growth of ~35.2 percent in revenues, ~32.6 percent in total economic impacts, and a compound annual growth rate (CAGR) of 5.25%. This places the mitigation industry within the range of other, well-established industries within the technical services sector. We suggest establishing North American Industry Classification System (NAICS) codes specifically for ecological restoration and mitigation firms, an essential step in generating accurate and consistent employment estimates in the future, particularly at sub-national geographic scales.

Real-Time Measurements of Gas-Phase Trichloramine (NCl3) in an Indoor Aquatic Center.

NCl3 is formed as a disinfection byproduct in chlorinated swimming pools and can partition between the liquid and gas phases. Exposure to gas-phase NCl3 has been linked to asthma and can irritate the eyes and respiratory airways, thereby affecting the health and athletic performance of swimmers. This study involved an investigation of the spatiotemporal dynamics of gas-phase NCl3 in an aquatic center during a collegiate swim meet. Real-time (up to 1 Hz) measurements of gas-phase NCl3 were made via a novel on-line derivatization cavity ring-down spectrometer and a proton transfer reaction time-of-flight mass spectrometer. Significant temporal variations in gas-phase NCl3 and CO2 concentrations were observed across varying time scales, from seconds to hours. Gas-phase NCl3 concentrations increased with the number of active swimmers due to swimming-enhanced liquid-to-gas transfer of NCl3, with peak concentrations between 116 and 226 ppb. Strong correlations between concentrations of gas-phase NCl3 with concentrations of CO2 and water (relative humidity) were found and attributed to similar features in their physical transport processes in pool air. A vertical gradient in gas-phase NCl3 concentrations was periodically observed above the water surface, demonstrating that swimmers can be exposed to elevated levels of NCl3 beyond those measured in the bulk air.

Chitayat syndrome: hyperphalangism, characteristic facies, hallux valgus and bronchomalacia results from a recurrent c.266A>G p.(Tyr89Cys) variant in the ERF gene.

BACKGROUND: In 1993, Chitayat et al., reported a newborn with hyperphalangism, facial anomalies, and bronchomalacia. We identified three additional families with similar findings. Features include bilateral accessory phalanx resulting in shortened index fingers; hallux valgus; distinctive face; respiratory compromise. OBJECTIVES: To identify the genetic aetiology of Chitayat syndrome and identify a unifying cause for this specific form of hyperphalangism. METHODS: Through ongoing collaboration, we had collected patients with strikingly-similar phenotype. Trio-based exome sequencing was first performed in Patient 2 through Deciphering Developmental Disorders study. Proband-only exome sequencing had previously been independently performed in Patient 4. Following identification of a candidate gene variant in Patient 2, the same variant was subsequently confirmed from exome data in Patient 4. Sanger sequencing was used to validate this variant in Patients 1, 3; confirm paternal inheritance in Patient 5. RESULTS: A recurrent, novel variant NM_006494.2:c.266A>G p.(Tyr89Cys) in ERF was identified in five affected individuals: de novo (patient 1, 2 and 3) and inherited from an affected father (patient 4 and 5). p.Tyr89Cys is an aromatic polar neutral to polar neutral amino acid substitution, at a highly conserved position and lies within the functionally important ETS-domain of the protein. The recurrent ERF c.266A>C p.(Tyr89Cys) variant causes Chitayat syndrome. DISCUSSION: ERF variants have previously been associated with complex craniosynostosis. In contrast, none of the patients with the c.266A>G p.(Tyr89Cys) variant have craniosynostosis. CONCLUSIONS: We report the molecular aetiology of Chitayat syndrome and discuss potential mechanisms for this distinctive phenotype associated with the p.Tyr89Cys substitution in ERF.

Estimating the Size and Impact of the Ecological Restoration Economy.

Domestic public debate continues over the economic impacts of environmental regulations that require environmental restoration. This debate has occurred in the absence of broad-scale empirical research on economic output and employment resulting from environmental restoration, restoration-related conservation, and mitigation actions - the activities that are part of what we term the "restoration economy." In this article, we provide a high-level accounting of the size and scope of the restoration economy in terms of employment, value added, and overall economic output on a national scale. We conducted a national survey of businesses that participate in restoration work in order to estimate the total sales and number of jobs directly associated with the restoration economy, and to provide a profile of this nascent sector in terms of type of restoration work, industrial classification, workforce needs, and growth potential. We use survey results as inputs into a national input-output model (IMPLAN 3.1) in order to estimate the indirect and induced economic impacts of restoration activities. Based on this analysis we conclude that the domestic ecological restoration sector directly employs ~ 126,000 workers and generates ~ $9.5 billion in economic output (sales) annually. This activity supports an additional 95,000 jobs and $15 billion in economic output through indirect (business-to-business) linkages and increased household spending.

Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion.

We tested the hypothesis that infusion of ascorbic acid (AA), a potent antioxidant, would alter vasodilator responses to exercise in human obesity and metabolic syndrome (MetSyn). Forearm blood flow (FBF, Doppler ultrasound) was measured in lean, obese, and MetSyn adults (n = 39, 32 ± 2 yr). A brachial artery catheter was inserted for blood pressure monitoring and local infusion of AA. FBF was measured during dynamic handgrip exercise (15% maximal effort) with and without AA infusion. To account for group differences in blood pressure and forearm size, and to assess vasodilation, forearm vascular conductance (FVC = FBF/mean arterial blood pressure/lean forearm mass) was calculated. We examined the time to achieve steady-state FVC (mean response time, MRT) and the rise in FVC from rest to steady-state exercise (Δ, exercise - rest) before and during acute AA infusion. The MRT (P = 0.26) and steady-state vasodilator responses to exercise (ΔFVC, P = 0.31) were not different between groups. Intra-arterial infusion of AA resulted in a significant increase in plasma total antioxidant capacity (174 ± 37%). AA infusion did not alter MRT or steady-state FVC in any group (P = 0.90 and P = 0.85, respectively). Interestingly, higher levels of C-reactive protein predicted longer MRT (r = 0.52, P < 0.01) and a greater reduction in MRT with AA infusion (r = -0.43, P = 0.02). We concluded that AA infusion during moderate-intensity, rhythmic forearm exercise does not alter the time course or magnitude of exercise-mediated vasodilation in groups of young lean, obese, or MetSyn adults. However, systemic inflammation may limit the MRT to exercise, which can be improved with AA.

Neural control of blood flow during exercise in human metabolic syndrome.

α-Adrenergic-mediated vasoconstriction is greater during simulated exercise in animal models of metabolic syndrome (MetSyn) when compared with control animals. In an attempt to translate such findings to humans, we hypothesized that adults with MetSyn (n = 14, 35 ± 3 years old) would exhibit greater α-adrenergic responsiveness during exercise when compared with age-matched healthy control subjects (n = 16, 31 ± 3 years old). We measured muscle sympathetic nerve activity (MSNA; microneurography) and forearm blood flow (Doppler ultrasound) during dynamic forearm exercise (15% of maximal voluntary contraction). α-Adrenergic agonists (phenylephrine and clonidine) and an antagonist (phentolamine) were infused intra-arterially to assess α-adrenergic receptor responsiveness and restraint, respectively. Resting MSNA was ∼35% higher in adults with MetSyn (P < 0.05), but did not change in either group with dynamic exercise. Clonidine-mediated vasoconstriction was greater in adults with MetSyn (P < 0.01). Group differences in vascular responses to phenylephrine and phentolamine were not detected (P > 0.05). Interestingly, exercise-mediated vasodilatation was greater in MetSyn (P < 0.05). Adults with MetSyn exhibit greater resting MSNA and clonidine-mediated vasoconstriction, yet preserved functional sympatholysis and higher exercise blood flow during low-intensity hand-grip exercise when compared with age-matched healthy control subjects. These results suggest that adults with MetSyn exhibit compensatory vascular control mechanisms capable of preserving blood flow responses to exercise in the face of augmented sympathetic adrenergic activity.

Microvascular function in younger adults with obesity and metabolic syndrome: role of oxidative stress.

Older adults with cardiovascular disease exhibit microvascular dysfunction and increased levels of reactive oxygen species (ROS). We hypothesized that microvascular impairments begin early in the disease process and can be improved by scavenging ROS. Forearm blood flow (Doppler ultrasound) was measured in 45 young (32 ± 2 yr old) adults (n = 15/group) classified as lean, obese, and metabolic syndrome (MetSyn). Vasodilation in response to endothelial (ACh) and vascular smooth muscle [nitroprusside (NTP) and epoprostenol (Epo)] agonists was tested before and after intra-arterial infusion of ascorbic acid to scavenge ROS. Vasodilation was assessed as a rise in relative vascular conductance (ml·min(-1)·dl(-1)·100 mmHg(-1)). ACh and NTP responses were preserved (P = 0.825 and P = 0.924, respectively), whereas Epo responses were lower in obese and MetSyn adults (P < 0.05) than in lean controls. Scavenging of ROS via infusion of ascorbic acid resulted in an increase in ACh-mediated (P < 0.001) and NTP-mediated (P < 0.001) relative vascular conductance across all groups, suggesting that oxidative stress influences vascular responsiveness in adults with and without overt cardiovascular disease risk. Ascorbic acid had no effect on Epo-mediated vasodilation (P = 0.267). These results suggest that obese and MetSyn adults exhibit preserved endothelium-dependent vasodilation with reduced dependence on prostacyclin and are consistent with an upregulation of compensatory vascular control mechanisms.

Altered neurovascular control of the resting circulation in human metabolic syndrome.

Young healthy adults exhibit an inverse linear relationship between muscle sympathetic nerve activity (MSNA) and α-adrenergic responsiveness. This balance may be reversed in metabolic syndrome (MetSyn) as animal models exhibit increased sympathetic activity and α-mediated vasoconstriction. We hypothesized humans with MetSyn would demonstrate increased α-adrenergic vasoconstriction and the inverse relationship between MSNA and adrenergic responsiveness would be lost. We measured MSNA (microneurography of the peroneal nerve) and forearm blood flow (FBF, Doppler ultrasound) in 16 healthy control subjects (31 ± 3 years) and 14 adults with MetSyn (35 ± 3 years; P > 0.05) during local administration of α-adrenergic agonists (phenylephrine (PE), α(1); clonidine (CL), α(2)). MSNA was greater in MetSyn subjects than in healthy controls (P < 0.05). A group difference in vasoconstriction to PE was not detected (P = 0.08). The level of α(1)-mediated vasoconstriction was inversely related to MSNA in control subjects (r = 0.5, P = 0.04); this balance between MSNA and α(1) responsiveness was lost in adults with MetSyn. MetSyn subjects exhibited greater vasoconstriction to CL infusion as compared with healthy controls (P < 0.01). A relationship between MSNA and α(2)-mediated vasoconstriction was not detected in either group. In summary, altered neurovascular control in human MetSyn is receptor specific. The observed uncoupling between MSNA and α(1)-adrenergic responsiveness and increased α(2) vasoconstriction may lead to reduced FBF, altered flow distribution, and/or severe hypertension with the progression toward diabetes and cardiovascular disease.

Effect of obesity and metabolic syndrome on hypoxic vasodilation.

This study was designed to test whether obese adults and adults with metabolic syndrome (MetSyn) exhibit altered hyperemic responses to hypoxia at rest and during forearm exercise when compared with lean controls. We hypothesized blood flow responses due to hypoxia would be lower in young obese subjects (n = 11, 24 ± 2 years, BMI 36 ± 2 kg m(-2)) and subjects with MetSyn (n = 8, 29 ± 3 years BMI 39 ± 2 kg m(-2)) when compared with lean adults (n = 13, 29 ± 2 years, BMI 24 ± 1 kg m(-2)). We measured forearm blood flow (FBF, Doppler Ultrasound) and arterial oxygen saturation (pulse oximetry) during rest and steady-state dynamic forearm exercise (20 contractions/min at 8 and 12 kg) under two conditions: normoxia (0.21 F(i)O(2), ~98% S(a)O(2)) and hypoxia (~0.10 F(i)O(2), 80% S(a)O(2)). Forearm vascular conductance (FVC) was calculated as FBF/mean arterial blood pressure. At rest, the percent change in FVC with hypoxia was greater in adults with MetSyn when compared with lean controls (p = 0.02); obese and lean adult responses were not statistically different. Exercise increased FVC from resting levels in all groups (p < 0.05). Hypoxia caused an additional increase in FVC (p < 0.05) that was not different between groups; responses to hypoxia were heterogeneous within and between groups. Reporting FVC responses as absolute or percent changes led to similar conclusions. These results suggest adults with MetSyn exhibit enhanced hypoxic vasodilation at rest. However, hypoxic responses during exercise in obese adults and adults with MetSyn were not statistically different when compared with lean adults. Individual hypoxic vasodilatory responses were variable, suggesting diversity in vascular control.

Metaplastic sarcomatoid carcinoma of the breast appears more aggressive than other triple receptor-negative breast cancers.

Metaplastic sarcomatoid carcinoma (MSC) of the breast is usually triple receptor (ER, PR, and HER2) negative and is not currently recognized as being more aggressive than other triple receptor-negative breast cancers. We reviewed archival tissue sections from surgical resection specimens of 47 patients with MSC of the breast and evaluated the association between various clinicopathologic features and patient survival. We also evaluated the clinical outcome of MSC patients compared to a control group of patients with triple receptor-negative invasive breast carcinoma matched for patient age, clinical stage, tumor grade, treatment with chemotherapy, and treatment with radiation therapy. Factors independently associated with decreased disease-free survival among patients with stage I-III MSC of the breast were patient age > 50 years (P = 0.029) and the presence of nodal macrometastases (P = 0.003). In early-stage (stage I-II) MSC, decreased disease-free survival was observed for patients with a sarcomatoid component comprising ≥ 95% of the tumor (P = 0.032), but tumor size was the only independent adverse prognostic factor in early-stage patients (P = 0.043). Compared to a control group of triple receptor-negative patients, patients with stage I-III MSC had decreased disease-free survival (two-sided log rank, P = 0.018). Five-year disease-free survival was 44 ± 8% versus 74 ± 7% for patients with MSC versus triple receptor-negative breast cancer, respectively. We conclude that MSC of the breast appears more aggressive than other triple receptor-negative breast cancers.

Heterogeneous vascular responses to hypoxic forearm exercise in young and older adults.

We aimed to assess age-related differences in compensatory hypoxic vasodilation during moderate-to-high dynamic exercise at absolute workloads. We hypothesized healthy older adults (n = 12, 61 ± 1 years) would exhibit impaired hypoxic vasodilation at a moderate absolute workload, and this effect would be exaggerated at a higher workload when compared to young adults (n = 17, 27 ± 2 years). Forearm blood flow (FBF) was measured with Doppler ultrasound. Dynamic forearm exercise (20 contractions/min) was completed at two absolute workloads (8 and 12 kg) under normoxic (0.21 FiO2, ~98% SpO2) and isocapnic hypoxic (~0.10 FiO2, 80% SpO2) conditions performed in random order. FBF was normalized as forearm vascular conductance (FBF / mean arterial blood pressure = FVC) to control for differences in blood pressure and to assess vasodilation. FVC increased with exercise and hypoxia (main effects, p < 0.05); vascular responses were not different between young and older adults (interaction effect exercise × group p = 0.37 and hypoxia × group p = 0.96). Results were confirmed when analyzed as either an absolute or relative change in FVC (ΔFVC and %ΔFVC, respectively). Although group responses to hypoxia were not different, individual results were highly variable (i.e., some adults constricted and others dilated to hypoxia). These data suggest (1) compensatory hypoxic vasodilation in older adults is not impaired during forearm exercise at both moderate and higher absolute exercise intensities, and (2) vascular responses to hypoxia are heterogeneous in both young and older adults. Results suggest unique individual differences exist in factors regulating vascular responses to hypoxia.

Implications of group III and IV muscle afferents for high-intensity endurance exercise performance in humans.

We investigated the influence of group III/IV muscle afferents on peripheral fatigue, central motor drive (CMD) and endurance capacity during high-intensity leg-cycling. In a double-blind, placebo-controlled design, seven males performed constant-load cycling exercise (318 ± 9 W; 80% of peak power output (W(peak))) to exhaustion under placebo conditions and with lumbar intrathecal fentanyl impairing spinal µ-opioid receptor-sensitive group III/IV muscle afferents. Peripheral fatigue was assessed via changes in pre- vs. post-exercise quadriceps force in response to supramaximal magnetic femoral nerve stimulation (ΔQ(tw,pot)). CMD was estimated via quadriceps electromyogram. To rule out a direct central effect of fentanyl, we documented unchanged resting cardioventilatory responses. Compared to placebo, significant hypoventilation during the fentanyl trial was indicated by the 9% lower V(E)/V(CO(2)), causing a 5 mmHg increase in end-tidal P(CO(2)) and a 3% lower haemoglobin saturation. Arterial pressure and heart rate averaged 8 and 10% lower, respectively, during the fentanyl trial and these differences progressively diminished towards end-exercise. Although initially similar, the percent change in CMD was 9 ± 3% higher at end-exercise with fentanyl vs. placebo (P < 0.05). Time to exhaustion was shorter (6.8 ± 0.3 min vs. 8.7 ± 0.3 min) and end-exercise ΔQ(tw,pot) was about one-third greater (-44 ± 2% vs. -34 ± 2%) following fentanyl vs. placebo. The rate of peripheral fatigue development was 67 ± 10% greater during the fentanyl trial (P < 0.01). Our findings suggest that feedback from group III/IV muscle afferents limits CMD but also minimizes locomotor muscle fatigue development by stimulating adequate ventilatory and circulatory responses to exercise. In the face of blocked group III/IV muscle afferents, CMD is less inhibited but O(2) transport compromised and locomotor muscle fatigability is exacerbated with a combined net effect of a reduced endurance performance.

Alpha-adrenergic control of blood flow during exercise: effect of sex and menstrual phase.

Sex differences exist in autonomic control of the cardiovascular system. This study was designed to directly test sex or female menstrual phase-related differences in α-adrenergic control of blood flow during exercise. We hypothesized that women would exhibit reduced α-adrenergic vasoconstriction compared with men during exercise; in addition, women would constrict less during the early luteal than the early follicular phase of the female menses. Young men (n = 10) were studied once and women (n = 9) studied twice, once during the early follicular phase and once during the early luteal phase of female menses. We measured forearm blood flow (FBF; Doppler ultrasound of the brachial artery) during rest and steady-state dynamic exercise (15 and 30% of maximal voluntary contraction, 20 contractions/min). A brachial artery catheter was inserted for the local administration of α-adrenergic agonists [phenylephrine (PE; α(1)) or clonidine (CL; α(2))]. Blood flow responses to exercise [forearm vascular conductance (FVC)] were similar between all groups. At rest, infusion of PE or CL decreased FVC in all groups (40-60% reduction). Vasoconstriction to PE was abolished in all groups at 15 and 30% exercise intensity. Vasoconstriction to CL was reduced at 15% and abolished at 30% intensity in all groups; women had less CL-induced constriction during the early luteal than early follicular phase (P < 0.017, 15% intensity). These results indicate that vasodilator responses to forearm exercise are comparable between men and women and are achieved through similar paths of α-adrenergic vascular control at moderate intensities; this control may differ at low intensities specific to the female menstrual phase.

Group III and IV muscle afferents contribute to ventilatory and cardiovascular response to rhythmic exercise in humans.

We investigated the role of somatosensory feedback on cardioventilatory responses to rhythmic exercise in five men. In a double-blind, placebo-controlled design, subjects performed the same leg cycling exercise (50/100/150/325 ± 19 W, 3 min each) under placebo conditions (interspinous saline, L(3)-L(4)) and with lumbar intrathecal fentanyl impairing central projection of spinal opioid receptor-sensitive muscle afferents. Quadriceps strength was similar before and after fentanyl administration. To evaluate whether a cephalad migration of fentanyl affected cardioventilatory control centers in the brain stem, we compared resting ventilatory responses to hypercapnia (HCVR) and cardioventilatory responses to arm vs. leg cycling exercise after each injection. Similar HCVR and minor effects of fentanyl on cardioventilatory responses to arm exercise excluded direct medullary effects of fentanyl. Central command during leg exercise was estimated via quadriceps electromyogram. No differences between conditions were found in resting heart rate (HR), ventilation [minute ventilation (VE)], or mean arterial pressure (MAP). Quadriceps electromyogram, O(2) consumption (VO(2)), and plasma lactate were similar in both conditions at the four steady-state workloads. Compared with placebo, a substantial hypoventilation during fentanyl exercise was indicated by the 8-17% reduction in VE/CO(2) production (VCO(2)) secondary to a reduced breathing frequency, leading to average increases of 4-7 Torr in end-tidal PCO(2) (P < 0.001) and a reduced hemoglobin saturation (-3 ± 1%; P < 0.05) at the heaviest workload (∼90% maximal VO(2)) with fentanyl. HR was reduced 2-8%, MAP 8-13%, and ratings of perceived exertion by 13% during fentanyl vs. placebo exercise (P < 0.05). These findings demonstrate the essential contribution of muscle afferent feedback to the ventilatory, cardiovascular, and perceptual responses to rhythmic exercise in humans, even in the presence of unaltered contributions from other major inputs to cardioventilatory control.

Milia after allergic contact dermatitis from poison ivy: two cases.

Milia have rarely been reported as a complication of severe allergic contact dermatitis. To our knowledge, milia have not previously been associated with poison ivy dermatitis. We present two cases of milia after allergic contact dermatitis to poison ivy.

Continuous infusion of enzyme replacement therapy is inferior to weekly infusions in MPS I dogs.

Intravenous enzyme replacement therapy with recombinant human α-L-iduronidase (rhIDU) is used weekly to treat mucopolysaccharidosis (MPS) I. We tested continuous administration of rhIDU at two dosing levels (0.58 mg/kg per week and 2 mg/kg per week) in MPS I dogs, and compared the efficacy of continuous infusion with the clinically used 0.58 mg/kg weekly three-hour infusion. Peak plasma concentrations of rhIDU were much higher in weekly-treated dogs (mean 256 units/ml) than steady-state concentrations in dogs treated with continuous infusion (mean 1.97 units/ml at 0.58 mg/kg per week; 8.44 units/ml at 2 mg/kg per week). Dogs receiving continuous IV rhIDU, even at a higher (2 mg/kg per week) dose, had consistently lower iduronidase levels in tissues than dogs receiving a weekly (0.58 mg/kg per week) dose. GAG storage was also less improved by continuous intravenous infusion. Adverse events were similar in all dosing groups. We found that continuous administration of 2 mg/kg per week rhIDU to MPS I dogs was insufficient to achieve GAG storage reduction comparable to 0.58 mg/kg weekly dosing.

Influence of toxic endophyte-infected fescue on sperm characteristics and endocrine factors of yearling Brahman-influenced bulls.

Sixteen (mean age = 1.1 +/- 0.1 yr; mean BW = 478 +/- 34 kg) Brahman-influenced bulls were used to determine the influence of fescue type on sperm characteristics and serum concentrations of prolactin, cortisol, and testosterone. Bulls were blocked by BW, scrotal circumference (SC), and pregrazing sperm characteristics and randomly assigned to graze toxic endophyte-infected (EI; 4 bulls/pasture; 2 pastures) or novel endophyte-infected (NE; 4 bulls/pasture; 2 pastures) tall fescue for 121 d. Semen was collected by electroejaculation, and SC was measured and blood samples collected monthly. Sperm were evaluated for motility and morphology with an integrated visual optical system. Overall mean concentration of prolactin was decreased more (P < 0.01) in EI bulls than NE bulls from May to August. Scrotal circumference was not affected by fescue type (P = 0.58); overall SC averaged 36.7 +/- 2.3 cm. Percentage of live sperm was not different (P = 0.24) between NE bulls (80%) than EI bulls (67%) in July and August. Bulls grazing NE fescue had more (P < 0.06) motile sperm than EI bulls in July and August. Percentages of progressive (57 vs. 38%, NE and EI, respectively; P < 0.06) and rapid (67 vs. 46%, NE and EI, respectively; P = 0.04) sperm were greater from bulls grazing NE than EI bulls in July and August. Average velocity of the smoothed sperm path and progressive velocity in a straight line from the beginning to the end of the sperm track were slower (P < 0.09) in EI bulls than NE bulls and were slower (P = 0.04) in August compared with July. Mean width of head oscillation as the sperm swims was less (P < 0.06) in August than July. Concentrations of cortisol and testosterone were not (P > 0.10) influenced by fescue type. Semen from bulls grazing EI had reduced motility and morphology than bulls grazing NE. Detrimental effects of toxic fescue may not be mediated by cortisol, testosterone, or both. Semen quality of bulls grazing toxic EI tall fescue was decreased with increased maximum ambient temperatures.