Use of an experimental high-magnesium tall fescue to reduce grass tetany in cattle

Grass tetany (hypomagnesemia) continues to be a problem for the livestock industry. An experimental cultivar of tall fescue (Festuca arundinacea Shreb.) selected for high Mg concentration, HiMag, was compared against four other cultivars for its ability to increase serum-Mg and reduce the risk of grass tetany. Forage from HiMag contained 22% more Mg, 183% more Ca, and 9% more P than other cultivars; K levels were not different. Regardless of cultivar, concentrations of Ca and Mg were lower while K and P were higher during the spring than the autumn. The tetany ratio IK/(Ca + Mg) on basis] was lower for HiMag than for other cultivars (1.34 vs. 1.65); all cultivars had a higher ratio during spring than autumn (1.91 vs. 1.31). In cattle (Bos taurus) grazing trials, blood serum from steers grazing HiMag contained 8% more Mg in autumn 1993 but was not different in spring 1994. Blood serum Mg was not different for cows (either dry or nursing calves) during autumn grazing, but approached significance (P = 0.09) during the spring 1995 calving season (2.32 vs. 2.07 mg/dL for HiMag vs. other cultivars). Except for differences between calves on HiMag compared with Kentucky-31 in autumn 1995 (58 vs. 43 lb, respectively), animal weight change was not affected by cultivar. Normal forage Mg concentrations (>0.20%) and tetany ratios below 2.2 for all cultivars in every season except spring 1995 may explain the lack of consistent animal response. No clinical symptoms of grass tetany were observed at any time during these studies. However, the higher Mg concentration and lower tetany ratio suggest that HiMag could provide a means of reducing the incidence of grass tetany in livestock during periods when risk of the disorder is high

Registration of HiMag Tall Fescue Germplasm

HiMag (Reg. no. GP-79, PI 615587) tall fescue (Festuca arundinacea Schreb.) was developed and released by the Missouri Agricultural Experiment Station and the USDA-ARS in 1997. HiMag has relatively high Mg and Ca concentrations and low tetany ratio [K/(Ca + Mg)] expressed as moles of charge. Parental germplasm for the Co cycle of selection for HiMag included 950 plants from 'Kenhy' (Buckner et al., 1977), 831 plants from 'Kentucky-31', and 688 plants from `Missouri-96' (Asay et al., 1979). All plants were endophyte free [ Neotyphodium coenophialum (Morgan-Jones and Gams) Glenn, Bacon, and Hanlin comb. nov.]. Parental plants were transplanted to the field near Columbia, MO, in the fall of 1983. The soil was a Mexico silt loam (a fine, montmorillonitic, mesic Udollic Ochraqualf) with a pH of 6.4. Selection was applied against crown rust (caused by Puccinia coronata Corda. var. coronata), leaving 1011 plants which were harvested in the fall of 1984 and analyzed for elemental concentrations of Mg, Ca, K, and the tetany ratio. Sixty-five plants (11 from Kentucky- 31, 54 from Missouri-96, and 0 from Kenhy) were chosen to generate the C1 cycle of selection. These 65 plants contained 5.0 to 7.0 g kg-1 Mg, 5.0 to 10.2 g kg' Ca, 20 to 33 g K, and had K/(Ca + Mg) values of 0.61 to 0.99. These were allowed to open-pollinate in the greenhouse during the winter of 1985/86. Harvested seeds were germinated in the greenhouse and seedlings were transplanted to the field in the fall of 1986. During the fall of 1987 approximately 1000 plants were analyzed from the CI cycle to determine elemental concentrations of Mg, Ca, K, and the tetany ratio. Forty-six plants chosen for the C2 contained 4.4 to 6.1 g kg -' Mg, 5.5 to 8.1 g kg-' Ca, 17.2 to 30.9 g kg' K, and had tetany ratios of 1.06 to 2.13. These were allowed to open-pollinate in the greenhouse in the winter of 1988-1989. Approximately 1000 seedlings were transplanted to the field having areas of Creldon silt loam (Mollic Fragiudalf) and Hobert silt loam (Umbric Fragiaqualf) at the Southwest Research Center, located near Mt. Vernon, MO, in the fall of 1989. In the summer of 1990, seed was harvested from these spaced plants and planted into an irrigated Portneuf silt loam soil (Durinodic Xeric Haplocalcid) to establish a seed increase block at Kimberly, ID, in April 1991. In 1992, seed from HiMag was harvested with the following characteristics: 1635 kg ha-1, 400 seeds g-1, 2.5 g 1000 seeds-1, and 302 kg m-3

Cold Gas in Cluster Cores

I review the literature's census of the cold gas in clusters of galaxies. Cold gas here is defined as the gas that is cooler than X-ray emitting temperatures (~10^7 K) and is not in stars. I present new Spitzer IRAC and MIPS observations of Abell 2597 (PI: Sparks) that reveal significant amounts of warm dust and star formation at the level of 5 solar masses per year. This rate is inconsistent with the mass cooling rate of 20 +/- 5 solar masses per year inferred from a FUSE [OVI] detection.Comment: 10 pages, conference proceeding

African-specific improvement of a polygenic hazard score for age at diagnosis of prostate cancer

Polygenic hazard score (PHS) models are associated with age at diagnosis of prostate cancer. Our model developed in Europeans (PHS46) showed reduced performance in men with African genetic ancestry. We used a cross-validated search to identify single nucleotide polymorphisms (SNPs) that might improve performance in this population. Anonymized genotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Ten iterations of a 10-fold cross-validation search were conducted to select SNPs that would be included in the final PHS46+African model. The coefficients of PHS46+African were estimated in a Cox proportional hazards framework using age at diagnosis as the dependent variable and PHS46, and selected SNPs as predictors. The performance of PHS46 and PHS46+African was compared using the same cross-validated approach. Three SNPs (rs76229939, rs74421890 and rs5013678) were selected for inclusion in PHS46+African. All three SNPs are located on chromosome 8q24. PHS46+African showed substantial improvements in all performance metrics measured, including a 75% increase in the relative hazard of those in the upper 20% compared to the bottom 20% (2.47-4.34) and a 20% reduction in the relative hazard of those in the bottom 20% compared to the middle 40% (0.65-0.53). In conclusion, we identified three SNPs that substantially improved the association of PHS46 with age at diagnosis of prostate cancer in men with African genetic ancestry to levels comparable to Europeans

Use of an experimental high-magnesium tall fescue to reduce grass tetany in cattle

Grass tetany (hypomagnesemia) continues to be a problem for the livestock industry. An experimental cultivar of tall fescue (Festuca arundinacea Shreb.) selected for high Mg concentration, HiMag, was compared against four other cultivars for its ability to increase serum-Mg and reduce the risk of grass tetany. Forage from HiMag contained 22% more Mg, 183% more Ca, and 9% more P than other cultivars; K levels were not different. Regardless of cultivar, concentrations of Ca and Mg were lower while K and P were higher during the spring than the autumn. The tetany ratio IK/(Ca + Mg) on basis] was lower for HiMag than for other cultivars (1.34 vs. 1.65); all cultivars had a higher ratio during spring than autumn (1.91 vs. 1.31). In cattle (Bos taurus) grazing trials, blood serum from steers grazing HiMag contained 8% more Mg in autumn 1993 but was not different in spring 1994. Blood serum Mg was not different for cows (either dry or nursing calves) during autumn grazing, but approached significance (P = 0.09) during the spring 1995 calving season (2.32 vs. 2.07 mg/dL for HiMag vs. other cultivars). Except for differences between calves on HiMag compared with Kentucky-31 in autumn 1995 (58 vs. 43 lb, respectively), animal weight change was not affected by cultivar. Normal forage Mg concentrations (>0.20%) and tetany ratios below 2.2 for all cultivars in every season except spring 1995 may explain the lack of consistent animal response. No clinical symptoms of grass tetany were observed at any time during these studies. However, the higher Mg concentration and lower tetany ratio suggest that HiMag could provide a means of reducing the incidence of grass tetany in livestock during periods when risk of the disorder is high

Registration of HiMag Tall Fescue Germplasm

HiMag (Reg. no. GP-79, PI 615587) tall fescue (Festuca arundinacea Schreb.) was developed and released by the Missouri Agricultural Experiment Station and the USDA-ARS in 1997. HiMag has relatively high Mg and Ca concentrations and low tetany ratio [K/(Ca + Mg)] expressed as moles of charge. Parental germplasm for the Co cycle of selection for HiMag included 950 plants from 'Kenhy' (Buckner et al., 1977), 831 plants from 'Kentucky-31', and 688 plants from `Missouri-96' (Asay et al., 1979). All plants were endophyte free [ Neotyphodium coenophialum (Morgan-Jones and Gams) Glenn, Bacon, and Hanlin comb. nov.]. Parental plants were transplanted to the field near Columbia, MO, in the fall of 1983. The soil was a Mexico silt loam (a fine, montmorillonitic, mesic Udollic Ochraqualf) with a pH of 6.4. Selection was applied against crown rust (caused by Puccinia coronata Corda. var. coronata), leaving 1011 plants which were harvested in the fall of 1984 and analyzed for elemental concentrations of Mg, Ca, K, and the tetany ratio. Sixty-five plants (11 from Kentucky- 31, 54 from Missouri-96, and 0 from Kenhy) were chosen to generate the C1 cycle of selection. These 65 plants contained 5.0 to 7.0 g kg-1 Mg, 5.0 to 10.2 g kg' Ca, 20 to 33 g K, and had K/(Ca + Mg) values of 0.61 to 0.99. These were allowed to open-pollinate in the greenhouse during the winter of 1985/86. Harvested seeds were germinated in the greenhouse and seedlings were transplanted to the field in the fall of 1986. During the fall of 1987 approximately 1000 plants were analyzed from the CI cycle to determine elemental concentrations of Mg, Ca, K, and the tetany ratio. Forty-six plants chosen for the C2 contained 4.4 to 6.1 g kg -' Mg, 5.5 to 8.1 g kg-' Ca, 17.2 to 30.9 g kg' K, and had tetany ratios of 1.06 to 2.13. These were allowed to open-pollinate in the greenhouse in the winter of 1988-1989. Approximately 1000 seedlings were transplanted to the field having areas of Creldon silt loam (Mollic Fragiudalf) and Hobert silt loam (Umbric Fragiaqualf) at the Southwest Research Center, located near Mt. Vernon, MO, in the fall of 1989. In the summer of 1990, seed was harvested from these spaced plants and planted into an irrigated Portneuf silt loam soil (Durinodic Xeric Haplocalcid) to establish a seed increase block at Kimberly, ID, in April 1991. In 1992, seed from HiMag was harvested with the following characteristics: 1635 kg ha-1, 400 seeds g-1, 2.5 g 1000 seeds-1, and 302 kg m-3