Effects of high-sulphur water on hepatic gene expression of steers fed fibre-based diets.

Sulphur-induced polioencephalomalacia (sPEM), a neurological disorder affecting ruminants, is frequently associated with the consumption of high-sulphur (S) water and subsequent poor performance. Currently, there is no economical method for S removal from surface water sources, and alternative water sources are typically neither readily available nor cost-effective. Determination of genes differentially expressed in response to high-S water consumption may provide a better understanding of the physiology corresponding to high dietary S and ultimately lead to the development of treatment and prevention strategies. The objective of this study was to determine changes in gene expression in the liver, an organ important for S metabolism, of fibre-fed steers consuming high-S water. For this study, liver tissues were collected on the final day of a trial from yearling steers randomly assigned to low-S water control (566 mg/kg SO4 ; n = 24), high-S water (3651 mg/kg SO4 ; n = 24) or high-S water plus clinoptilolite supplemented at either 2.5% (n = 24) or 5.0% (n = 24) of diet dry matter (DM). Microarray analyses on randomly selected healthy low-S control (n = 4) and high-S (n = 4; no clinoptilolite) steers using the Affymetrix GeneChip Bovine Genome Array revealed 488 genes upregulated (p < 0.05) and 154 genes downregulated (p < 0.05) in response to the high- vs. low-S water consumption. Real-time RT-PCR confirmed the upregulation (p < 0.10) of seven genes involved in inflammatory response and immune functions. Changes in such genes suggest that ruminant animals administered high-S water may be undergoing an inflammation or immune response, even if signs of sPEM or compromised health are not readily observed. Further study of these, and other affected genes, may deliver new insights into the physiology underlying the response to high dietary S, ultimately leading to the development of treatments for high S-affected ruminant livestock.

Deviant neurophysiological asymmetry in children with language impairment.

Deviant anatomical asymmetry of perisylvian cortex is argued to be linked to specific language impairment (SLI). However, no studies have examined whether deviant functional asymmetry underlies the processing of spoken language. In the current study, brain-electrical activity was recorded from 31 scalp sites to the function word 'the' embedded in auditorally presented stories and nonsense contexts. The SLI children showed reversed asymmetry at electrode sites over temporal cortex compared to control children in processing this word in all contexts. They also appear to lack some contribution from a deep neural generator in processing 'the' in the story. This investigation is the first to demonstrate a direct link between deviant neurophysiological asymmetry and the processing of spoken language in children with SLI.

Predictive accuracy of bioimpedance equations in estimating fat-free mass of Hispanic women.

This study assessed the predictive accuracy of previously published bioelectrical impedance analysis equations for estimating fat-free mass of young (20-39 yr) Hispanic women (N = 29). The reference method was hydrostatic weighing at residual lung volume. Body density was converted to percent body fat using the Siri equation. Resistance and reactance were measured with a Valhalla bioimpedance analyzer. The bioelectrical impedance analysis equations of Lohman, Rising, Stolarczyk, Segal, Gray, and Van Loan were cross-validated. There were significant correlations between criterion and predicted fat-free mass (r = 0.86-0.95) for all equations. The standard error of estimate for each equation was acceptable; however, the total error for the Stolarczyk (3.2 kg) and the Van Loan (4.6 kg) equations exceeded the recommended value (2.8 kg). For all equations, the difference between average criterion and predicted fat-free mass was significant (P < 0.05). However, the mean differences for the Lohman (0.8 kg), Segal (0.8 kg), and Gray (0.9 kg) equations were small. In conclusion, the Segal, Lohman, and Gray equations may have potential for assessing the body composition of healthy, acculturated, Hispanic women.

Neurophysiological indices of language impairment in children.

Recent investigations of children with specific language impairment (SLI) have found deviant anatomical asymmetry of the perisylvian cortex. These studies argue that this deviant anatomical asymmetry is linked to the language disorders of SLI children. To date no studies have examined whether deviant functional asymmetry underlies the processing of spoken language in these children. In the current study, brain-electrical activity was recorded from 31 scalp sites while children with SLI listened to auditorally presented stories and two different nonsense contexts. Electrical activity was time-locked to the grammatical word "the" in these contexts. The SLI children showed reversed asymmetry compared to control children from 200 ms to 400 ms in processing "the" in all contexts. More specifically, they showed depressed processing at the left temporal scalp site (T7) and enhanced processing at the right temporal site (T8). The second spatial derivative (the Laplacian) of the voltage activity was calculated to remove constant voltage potential and uniform changes in voltage potential across the scalp. The Laplacian analysis indicated that the sources of the positive electrical activity seen at the temporal electrode sites T7 and T8 are the lateral surfaces of the temporal cortices. A comparison of the scalp topography of the voltage potentials and Laplacian also suggests that children with SLI lack some contribution from a deep neural generator, possibly in the hippocampus or basal ganglia. This investigation is the first to demonstrate a direct link between deviant neurophysiological asymmetry and the processing of spoken language in children with SLI.

Effects of supplemental molybdenum on animal performance, liver copper concentrations, ruminal hydrogen sulfide concentrations, and the appearance of sulfur and molybdenum toxicity in steers receiving fiber-based diets.

Poor performance and S-induced polioencephalomalacia (sPEM) have been observed in ruminant livestock in high-S drinking water regions. No gainful method of removing S from drinking water is available and therefore a feed supplement that negates the effects of high-S water is needed. Our objective was to determine if supplementing Mo improves health and performance of steers administered a high-fiber diet and high-S drinking water. We hypothesized that if the supplemental Mo adequately bound excess S in the rumen, it would not be available at toxic concentrations. Yearling steers (n = 96; 260.0 ± 1.3 kg BW) were stratified by pretrial BW into 12 feedlot pens (n = 8 steers per pen). One of 3 treatments, low-S water (LS; 375 mg SO(4)/L), high-S water (HS; 2,218 mg SO(4)/L), or high-S water plus Mo (HSMO; 2,218 mg SO(4)/L; 187.5 mg Mo/kg DM), were randomly assigned to pens within 4 blocks for a 56-d trial. Body weights were recorded on d -2, -1, 29, 56, and 57, ruminal H(2)S concentrations were measured by rumenocentesis on d -1, 29, and 57, and liver biopsies were performed on d -1 and 57. Performance data were analyzed over the 56-d trial period (overall) as well as over 2 periods: Period 1 (d 0 to d 28) and Period 2 (d 29 to d 56). One case of sPEM was confirmed by the presence of cortical lesions in the HS treatment group. Daily DMI and ADG were affected by treatment and period (P < 0.001) main effects. The LS steers had the greatest (P < 0.05) DMI followed by HS and HSMO steers, respectively. Similar results were observed for ADG. Daily water intake was affected (P < 0.001) by period only, with greater daily water intake in Period 2 than Period 1. Change in hepatic concentrations of Cu, Fe, and Mo over the course of the trial were all affected (P < 0.001) by treatment. Hepatic Cu increased from d 1 to 57 in LS and HS steers but was depleted in HSMO steers. Hepatic Fe and Mo increased in HSMO steers only. Ruminal H(2)S concentrations were affected by treatment (P < 0.021), with greater H(2)S concentrations in HSMO compared with LS and HS steers. Signs of Mo toxicity such as severe diarrhea, loss of body condition, anorexia, changes in hair color, and stiffness in joints were observed in the Mo supplemented steers. These results indicate that added dietary Mo does not adequately bind excess S in the rumen, causing aggravated toxic effects from potentially both the high dietary S and Mo.

Effects of high-sulfur water and clinoptilolite on health and growth performance of steers fed forage-based diets.

Sulfur-induced polioencephalomalacia (sPEM), a neurological disorder affecting ruminants, is associated with consumption of diets with increased S (high-S). High-S water is commonly found in many western states and is a major source of dietary S for grazing cattle. Consumption of high-S water has been associated with sPEM and decreased performance. Identification of a feed supplement that would counteract the negative effects of high-S water would decrease the incidence of sPEM and prevent performance reductions in regions with problematic water sources. The objectives of this study were to 1) determine the effects of administering high-S drinking water to forage-fed feedlot steers on health and performance, and 2) determine the effectiveness of clinoptilolite, a clay mineral with increased cation-exchange capacity, in negating the effects of high-S drinking water. Yearling steers (n = 96; 318.2 +/- 2.1 kg of BW) were randomly assigned to 1 of 4 treatments for a 77-d trial period: control with low-S water (566 mg of SO(4)/L), high-S water (3,651 mg of SO(4)/L), or high-S water plus clinoptilolite supplemented at 2.5 or 5.0% of the diet DM. Feed and water consumption were measured daily, and all steers were weighed on d -2, -1, 29, 53, 76, and 77. Plasma samples were collected on d 0, 58, and 77, and liver samples on d 0 and 77. There was a greater (P or= 0.546) in ADG or G:F were observed. Plasma Cu decreased (P = 0.029) to a greater magnitude in high-S water steers than the control steers over the 77-d trial period. Mineral analyses of hepatic tissue from randomly selected healthy steers from each treatment group (n = 10 per treatment) showed an interaction (P

Effects of dietary aflatoxin on the health and performance of growing barrows.

Aflatoxins, especially aflatoxin B1 (AFB1), can be greater in dried distillers grains with solubles (DDGS) because it can be concentrated during the ethanol production process. Increased use of DDGS in swine diets could potentially lead to an increased incidence of aflatoxicosis, a disease associated with decreased feed intake, reduced BW gain, and impaired liver function. The objective of this study was to determine the effects of AFB1 on the health, performance, and serum profile of growing barrows. Ninety Duroc × Yorkshire crossbred barrows were purchased (age = 35 ± 5 d; BW = 14.2 ± 3.0 kg), allocated to 9 pens with 10 pigs per pen, and randomly assigned to receive diets containing 0 µg/kg of AFB1 (CON), 250 µg/kg of AFB1 (LO), or 500 µg/kg of AFB1 (HI) for 7, 28, or 70 d in a 3 × 3 factorial arrangement of treatments. Feed intake was measured daily, and pigs were weighed and blood samples collected weekly. Serum was analyzed for concentrations of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (BILI), and blood urea nitrogen (BUN). Both ADFI and ADG were negatively affected (P ≤ 0.001) by AFB1 treatment. Average daily feed intake was less (P < 0.05) in HI barrows than in CON barrows from wk 5 to 10 and was less (P < 0.05) in LO barrows than in CON barrows in wk 5 and again from wk 8 to 10. Also, ADFI was less (P = 0.022) in HI barrows than LO barrows in wk 10. Decreased ADG (P < 0.05) was observed in HI barrows than in CON barrows in wk 8 and 10; no differences (P ≥ 0.665) in ADG were noted between CON and LO barrows. There was no effect (P ≥ 0.080) of AFB1 treatment on ALT or BILI concentrations. However, both AST and BUN were affected (P < 0.05) by AFB1 treatment. Serum AST was greater (P = 0.010) in LO barrows than CON barrows in wk 5, and serum BUN was greater (P = 0.004) in CON barrows than LO barrows in wk 3. Results from this study demonstrate that the performance and health of young growing barrows were affected by consumption of an AFB1-contaminated diet, especially when fed for a more extended period.