Effects of wildfire smoke PM2.5 on indicators of inflammation, health, and metabolism of preweaned Holstein heifers.

Wildfires are a growing concern as large, catastrophic fires are becoming more commonplace. Wildfire smoke consists of fine particulate matter (PM2.5), which can cause immune responses and disease in humans. However, the present knowledge of the effects of wildfire PM2.5 on dairy cattle is sparse. The present study aimed to elucidate the effects of wildfire-PM2.5 exposure on dairy calf health and performance. Preweaned Holstein heifers (N = 15) were assessed from birth through weaning, coinciding with the 2021 wildfire season. Respiratory rate, heart rate, rectal temperatures, and health scores were recorded and blood samples were collected weekly or twice a week for analysis of hematology, blood metabolites, and acute phase proteins. Hourly PM2.5 concentrations and meteorological data were obtained, and temperature-humidity index (THI) was calculated. Contribution of wildfires to PM2.5 fluxes were determined utilizing AirNowTech Navigator and HYSPLIT modeling. Mixed models were used for data analysis, with separate models for lags of up to 7 d, and fixed effects of daily average PM2.5, THI, and PM2.5 × THI, and calf as a random effect. THI ranged from 48 to 73, while PM2.5 reached concentrations up to 118.8 µg/m3 during active wildfires. PM2.5 and THI positively interacted to elevate respiratory rate, heart rate, rectal temperature, and eosinophils on lag day 0 (day of exposure; all P < 0.05). There was a negative interactive effect of PM2.5 and THI on lymphocytes after a 2-d lag (P = 0.03), and total white blood cells, neutrophils, hemoglobin, and hematocrit after a 3-d lag (all P < 0.02), whereas there was a positive interactive effect on cough scores and eye scores on lag day 3 (all P < 0.02). Glucose and NEFA were increased as a result of combined elevated PM2.5 and THI on lag day 1, whereas BHB was decreased (all P < 0.05). Contrarily, on lag day 3 and 6, there was a negative interactive effect of PM2.5 and THI on glucose and NEFA, but a positive interactive effect on BHB (all P < 0.03). Serum amyloid A was decreased whereas haptoglobin was increased with elevated PM2.5 and THI together on lag days 0 to 4 (all P < 0.05). These findings indicate that exposure to wildfire-derived PM2.5, along with increased THI during the summer months, elicits negative effects on preweaned calf health and performance both during and following exposure.

Wildfires contribute to fine particulate matter (PM2.5) pollution throughout the United States. Wildfire-PM2.5 exposure negatively affects human health and dairy cow production; however, the effects on calves are not known. We monitored preweaned calves exposed to natural wildfires to understand how wildfire-PM2.5 exposure affects calf health and performance. Calves exposed to wildfire PM2.5 and elevated temperature­humidity index (THI) experienced respiratory symptoms, alterations in blood cell composition and metabolism, and changes in circulating inflammatory proteins. These results suggest that PM2.5 along with increased THI induced an inflammatory response and alterations in energy metabolism that may contribute to calf health and performance deficits.

Screening for Cardiovascular Disease Risk Factors in a Physical Therapist Wound Care Practice: A Retrospective, Observational Study.

Understanding the prevalence of cardiovascular risk factors among individuals seeking physical therapist services in a wound care center is important, especially if aerobic exercise or other physical activity is recommended. PURPOSE: This study assessed the prevalence of cardiovascular risk factors in individuals seeking physical therapist services for an integumentary disorder in an outpatient wound care center. METHODS: Using a retrospective, observational study design, records from patients who were screened upon initial evaluation by a physical therapist for cardiovascular risk according to the American College of Sports Medicine (ACSM) guidelines were abstracted. The screening process entailed assessment of current signs and symptoms of cardiovascular, pulmonary, or metabolic disease; an individual or family history of cardiovascular disease; whether the patient was considered obese; and whether the patient was a current smoker, had a sedentary lifestyle, dyslipidemia, elevated glucose, or blood pressure ⟩140/90 mm Hg. Patient demographics and wound history also were summarized and described, including wound type and duration and pain associated with the wound. Wounds then were classified by the physical therapist as either venous leg ulcers or nonvenous leg ulcers based upon the referring physician's diagnosis. Descriptive statistics and frequency distributions were calculated to assess the prevalence of individual cardiovascular risk factors, total number of cardiovascular risk factors, cardiovascular risk stratification, and patient disposition. Frequencies of individual cardiovascular risk factors, total number of cardiovascular risk factors, and cardiovascular risk stratification also were assessed between patients with venous leg ulcers and nonvenous leg ulcers using chi-square tests for categorical data and t tests for continuous data. The alpha level was set at P <.05. RESULTS: Among the 70 study participants (41 male, 29 female; mean age 63.5 ± 15.1 years), 38 were treated for venous leg ulcers and 32 were treated for nonvenous leg ulcers. Overall, 38 patients (54%) had a history of cardiovascular disease and 29 (41%) had current signs and symptoms of cardiovascular disease. Patients with nonvenous leg ulcers had a significantly higher frequency of having a family history of cardiovascular disease than patients with venous leg ulcers (28% vs. 8%; P = .03). According to the ACSM guidelines, 5 patients (7%) were considered low risk, 22 (31%) were moderate risk, and 43 (62%) were at high risk for experiencing a future cardiovascular event. Cardiovascular risk did not vary significantly according to wound type. CONCLUSION: The patient risk-stratification profile in this study strongly suggested physical therapists should screen for cardiovascular risk factors before prescribing aerobic exercise or other physical activity for all patients being seen for an integumentary disorder in an outpatient wound care practice.