Penetrating Ionizing Radiation Levels Observed in the Lower Arkansas and White River Valleys of Arkansas

Environmental levels of penetrating ionizing radiation were measured in the lower Arkansas and White River valleys of Arkansas. Measurements of environmental gamma and cosmic rays were made using a portable high pressure ionization chamber. The surveyed area encompassed a large coal-fired industrial plant. Observed exposure rates ranged from 5.9 microRoentgens per hour (μR/h) to 13.4 μR/h. The average exposure rate for the region was 8.8 μR/h. This value corresponds to 77 millirem (mrem) or 0.77 milliSieverts (mSv) per year. In comparison, a prior state-wide survey reported an average dose equivalent rate of 78.2 mrem (0.782 mSv) per year in Arkansas

Red Imported Fire Ant Impacts on Upland Arthropods in Southern Mississippi

Red imported fire ants (Solenopsis invicta) have negative impacts on a broad array of invertebrate species. We investigated the impacts of fire ants on the upland arthropod community on 20-40 ha study sites in southern Mississippi. Study sites were sampled from 1997–2000 before, during, and after fire ant bait treatments to reduce fire ant populations. Fire ant abundance was assessed with bait transects on all sites, and fire ant population indices were estimated on a subset of study sites. Species richness and diversity of other ant species was also assessed from bait transects. Insect biomass and diversity was determined from light trap samples. Following treatments, fire ant abundance and population indices were significantly reduced, and ant species diversity and richness were greater on treated sites. Arthropod biomass, species diversity and species richness estimated from light trap samples were negatively correlated with fire ant abundance, but there were no observable treatment effects. Solenopsis invicta has the potential to negatively impact native arthropod communities resulting in a potential loss of both species and function

Red Imported Fire Ant Impacts on Upland Arthropods in Southern Mississippi

Red imported fire ants (Solenopsis invicta) have negative impacts on a broad array of invertebrate species. We investigated the impacts of fire ants on the upland arthropod community on 20-40 ha study sites in southern Mississippi. Study sites were sampled from 1997–2000 before, during, and after fire ant bait treatments to reduce fire ant populations. Fire ant abundance was assessed with bait transects on all sites, and fire ant population indices were estimated on a subset of study sites. Species richness and diversity of other ant species was also assessed from bait transects. Insect biomass and diversity was determined from light trap samples. Following treatments, fire ant abundance and population indices were significantly reduced, and ant species diversity and richness were greater on treated sites. Arthropod biomass, species diversity and species richness estimated from light trap samples were negatively correlated with fire ant abundance, but there were no observable treatment effects. Solenopsis invicta has the potential to negatively impact native arthropod communities resulting in a potential loss of both species and function

Effect of Total Dissolved Solids and Sulfates in Drinking Water for Growing Steers

A study was conducted to determine the effects of implants and transportation on the metabolic status of feedlot steers. Steers (n = 28) were sorted by body weight, allocated into light or heavy blocks, and randomly assigned to one of two treatments. Treatments included non-implanted controls (CON) and steers implanted with Synovex Plus 70 d prior to harvest (IMP). Jugular blood and muscle biopsy samples (longissimus dorsi (LD) and semimembranosis (SM)) were collected 70 d post-implant, prior to transit. Steers were transported to Schuyler, NE, where blood and biopsy sampling was repeated. After harvest, carcass data were collected and muscle samples were taken from the LD, SM, Psoas Major (PM), and Illiacus (IL) muscles. Implanting increased (P \u3c 0.05) estradiol levels and improved live animal performance. Carcass weight and rib eye area were increased (P \u3c 0.05) in implanted steers. No dark cutters were found in either treatment. Pre-transit insulin/glucagon ratio and muscle glycogen levels did not differ (P \u3e 0.10) between treatments. Non-esterified fatty acid (NEFA) levels were reduced (P \u3c 0.05) in implanted steers pre-transit. Transit increased (P \u3c 0.05) NEFA levels, but had no effect (P \u3e 0.10) on insulin/glucagon ratio or muscle glycogen levels. Implanting did not affect (P \u3e 0.10) insulin/glucagon ratio, NEFA, or LD glycogen levels post-transit. Implanted steers had lower (P \u3c 0.05) glycogen levels in the SM than did non-implanted steers post-transit. Weight block affected (P \u3c 0.05) insulin and insulin/glucagon ratio levels, with steers in the light block having greater levels of each. Muscle pH and objective color (L*, a*, b*) of the LD were not biologically different between treatments. Implanted steers had greater (P \u3c 0.05) glycolytic potential values in the LD, and tended (P \u3c 0.10) to have higher L* values in the PM. Implanting increased (P \u3c 0.05) shear force of the LD. These data indicate that although implants affect bovine metabolism, other factors are necessary to cause a sufficient reduction in muscle glycogen and to produce a dark cutting carcass

Effect of Calving Time and Weaning Time on Cow and Calf Performance - A Preliminary Report

Cows grazing native range year round were allotted to 3 management systems: 1.) A calving season starting in mid March with calves weaned in late October; 2) A calving season starting in mid March with calves weaned in mid September; and 3) A calving season starting early May with calves weaned in late October. After 2 years of the study, pregnancy rate and calving interval were not affected by management system. Average weaning weight was the highest for the March calving/October weaned group in both years. In the first year of the study, severe winter weather caused a lower calf survival to weaning for the March calving groups compared to the May calving group. This resulted in similar pounds of calf weaned per cow exposed for the March calving/October weaned and May calving1October weaned groups. Estimated income per exposed female was similar for these two groups. In the second year of the study, calf death loss was not affected by calving time. The heavier weaning weights of the March calving /October weaned group resulted in more pounds weaned per cow exposed and $30 greater income per exposed female. The potential to reduce costs for winterfeed, equipment, calving facilities and labor would favor later calving and must be considered

Effect of Calving Time and Weaning Time on Feedlot Performance - A Preliminary Report

Cows grazing native range year round at the SDSU Cottonwood Research Station were allotted to 3 management systems; Group 1) a calving season starting in mid March with calves weaned in late October, Group 2) a calving season starting in mid March with calves weaned in mid September, and Group 3) a calving season starting early May with calves weaned in late October. Following weaning the steer calves are transported to the Southeast South Dakota Experiment Farm. For two calf crops the steer calves have been fed a high grain diet for maximum gain from weaning to harvest. Group 2 had a lower mean average daily gain than Groups 1 and 3. Feed conversion was not affected by treatment. There was not a consistent indication that groups weaned at a younger age (Groups 2 and 3) had more health problems than Group 1. Group 3 had the highest mean dressing percentage and carcass weight. Weaning at a younger age and a longer time on feed resulted in higher marbling scores for Group 2 compared to Group 1. This advantage in marbling was not observed for Group 3