@article{drewnoski_huntington_poore_2014, title={Reduced supplementation frequency increased insulin-like growth factor 1 in beef steers fed medium quality hay and supplemented with a soybean hull and corn gluten feed blend}, volume={92}, ISSN={["1525-3163"]}, DOI={10.2527/jas.2013-7372}, abstractNote={Reducing supplementation frequency in calf growing programs can reduce labor and equipment operation costs. However, little is understood about the metabolic response of ruminants to large fluctuations in nutrient intake. Eighteen Angus or Angus × Simmental cross steers (287 ± 20 kg and 310 ± 3.6 d of age) were individually fed 1 of 3 dietary treatments using Calan gates. Dietary treatments consisted of ad libitum hay and no supplement (NS), ad libitum hay and 1% BW (as-fed basis) of supplement daily (DS), or ad libitum hay and 2% BW (as-fed basis) of supplement every other day (SA). The supplement was 90% DM and contained (as-fed basis) 47% corn gluten feed, 47% soybean hulls, 2% feed grade limestone, and 4% molasses. Hay intake and ADG was measured over a 52-d period. Steers were then moved to individual tie stalls. Steers were fed at 0800 h and blood samples were collected every hour from 0600 to 1400 h and at 1800, 2200, and 0200 h over a 2-d period. Gains were increased (P < 0.01) by supplementation but did not differ (P = 0.68) due to supplementation frequency. Average daily gain was 0.45, 0.90, and 0.87 kg ·hd(-1)·d(-1) (SEM ± 0.05) for steers NS, DS, and SA, respectively. Across the 2-d supplementation cycle area under the concentration time curve (AUC) for plasma glucose was increased (P < 0.01) by supplementation but did not differ (P = 0.41) due to supplementation frequency. The AUC for plasma insulin was increased by supplementation (P < 0.01) but did not differ (P = 0.67) due to supplementation frequency. Plasma IGF-1 was increased (P = 0.01) by supplementation and was greater (P = 0.04) for steers supplemented SA than DS. Gains of steers supplemented with a soybean hull and corn gluten feed blend on alternate days did not differ from those supplemented daily suggesting the steers were able to efficiently utilize large boluses of nutrients fed every other day. The effect of less frequent supplementation on IGF-1 deserves further examination as this hormone has been shown to increase protein synthesis.}, number={6}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Drewnoski, M. E. and Huntington, G. B. and Poore, M. H.}, year={2014}, month={Jun}, pages={2546–2553} }
 @article{drewnoski_poore_benson_2011, title={Effect of frequency of supplementation of a soyhulls and corn gluten feed blend on hay intake and performance of growing steers}, volume={164}, ISSN={["0377-8401"]}, DOI={10.1016/j.anifeedsci.2010.11.022}, abstractNote={Abstract Feeding supplements less frequently can reduce labor costs and increase profitability. However reducing the frequency of delivery of grain based supplements can negatively affect fiber digestion in the rumen because more grain must be fed per feeding potentially causing decreased ruminal pH and/or an insufficiency of ruminal nitrogen. Using supplements that have a moderate crude protein (CP) level, and that are low in starch, might alleviate negative effects on fiber digestion and therefore decrease negative effects associated with supplementing energy supplements less frequently. Corn gluten feed and soybean hulls are high in metabolizable energy but low in fat and starch, and corn gluten feed is also a good source of ruminally degradable CP. The objective of this study was to determine effects of reducing supplementation frequency during a weekly cycle on steer performance when supplementing medium quality hay with a blend of soybean hulls and corn gluten feed (SH/CGF). The 86 d feeding experiment was replicated over 4 years. Each year, 40 steers (BW = 263 ± 2.5, 281 ± 2.5, 271 ± 2.9, 229 ± 2.9 kg for years 1–4, respectively) were stratified by body weight and assigned to 8 groups which were randomly assigned to treatment. During years 1 and 2, treatments consisted of ad libitum medium quality fescue hay (70–100 g/kg CP and 340–410 g/kg acid detergent fiber) that was either not supplemented (HAY), supplemented daily (7X) with 2.73 kg/hd, or supplemented on Monday, Wednesday and Friday (3X) with 6.36 kg/hd. During years 3 and 4, an additional treatment was added in which steers were supplemented on Monday and Thursday with 9.55 kg/hd of SH/CGF (2X). Average daily gain was higher (P}, number={1-2}, journal={ANIMAL FEED SCIENCE AND TECHNOLOGY}, author={Drewnoski, M. E. and Poore, M. H. and Benson, G. A.}, year={2011}, month={Feb}, pages={38–44} }
 @article{drewnoski_poore_benson_2011, title={Effect of frequency of supplementation of a soyhulls and corn gluten feed blend on hay intake and performance of growing steers (vol 164, pg 38, 2011)}, volume={168}, ISSN={["0377-8401"]}, DOI={10.1016/j.anifeedsci.2011.04.056}, number={1-2}, journal={ANIMAL FEED SCIENCE AND TECHNOLOGY}, author={Drewnoski, M. E. and Poore, M. H. and Benson, G. A.}, year={2011}, month={Aug}, pages={144–144} }
 @article{drewnoski_oliphant_poore_green_hockett_2009, title={Growth and reproductive performance of beef heifers grazing endophyte-free, endophyte-infected and novel endophyte-infected tall fescue}, volume={125}, DOI={10.1016/j.livsci.2009.05.003}, abstractNote={A three-year study was conducted to investigate the effects of endophyte-free (E−), endophyte-infected (E+) and novel endophyte-infected (EN) tall fescue on the growth and pregnancy rate of beef heifers during the spring. Each year, 48 beef heifers were strip-grazed on stockpiled fescue from December through February, fed fescue hay during late February to early April and then rotationally grazed on spring growth of fescue until June. At the end of the trial, heifers had been maintained on E+, E− or EN (pasture or hay) for a total of 152, 188 and 191 d in years 1, 2, and 3, respectively. In late March, heifers were synchronized using a controlled intravaginal drug-releasing device, (CIDR®) for 7 d followed by injection with PGF2α (Lutalyse®). Heatmount detectors (Kamar®) and observation for behavioral estrus were used to detect estrus for 63 d. Heifers were artificially inseminated 8 to12 h after the onset of standing estrus. Conception was determined by transrectal ultrasonography at approximately 30, 60 and 90 d after synchronization. Reproductive performance did not differ among treatments (P ≥ 0.20). Pregnancy rate was 54, 65, and 65% for E+, E− and EN, respectively. However, during the spring, growth and prolactin were decreased (P < 0.01) for heifers on E+. Gains on spring pasture were 0.24, 0.75, and 0.71 kg/d (SEM ± 0.03) for E+, E− and EN, respectively. Based on these results, the wild type endophyte-infected fescue can be used in production systems as a source of winter forage but producers should consider placing heifers on alternative forage (such as the novel endophyte-infected fescue) in the spring.}, number={2-3}, journal={Livestock Science}, author={Drewnoski, M. E. and Oliphant, E. J. and Poore, M. H. and Green, J. T. and Hockett, M. E.}, year={2009}, pages={254–260} }
 @article{drewnoski_oliphant_marshall_poore_green_hockett_2009, title={Performance of growing cattle grazing stockpiled Jesup tall fescue with varying endophyte status}, volume={87}, ISSN={["1525-3163"]}, DOI={10.2527/jas.2008-0977}, abstractNote={The objective of this study was to evaluate the performance of growing cattle when intensively grazing stockpiled endophyte-infected (E+), endophyte-free (E-), and nontoxic endophyte-infected (EN) tall fescue during the winter. The experiment was conducted over 5 consecutive winters. In each year, plots (1 ha each, 4 per treatment) were harvested for hay in August, fertilized in September, and forage was allowed to accumulate until grazing was initiated in early December. Each year, 48 Angus-cross tester cattle (4 per plot) were given a daily allotment of forage, under strip-grazing (frontal grazing) management, with a target residual height of 5 cm. Steers were used the first year, and heifers were used in subsequent years. The grazing periods for determination of pasture ADG were 86 d (yr 1), 70 d (yr 2), 86 d (yr 3), 72 d (yr 4), and 56 d (yr 5). Pasture ADG of cattle did not differ among treatments (P = 0.13) and were 0.51, 0.59, and 0.56 kg/d (SEM 0.03) for E+, E-, and EN, respectively. Serum prolactin concentrations of heifers grazing E+ were less (P < 0.05) than those grazing E- and EN during all years except yr 2. In yr 2, E+ and E- did not differ (P = 0.11). Serum prolactin of heifers grazing E- and EN did not differ (P > 0.20) except in yr 4. During yr 4, serum prolactin of heifers grazing E- was greater (P = 0.05) than that of heifers grazing EN. Serum urea-N concentrations (SUN) tended to differ among treatments (P = 0.10) and there was a treatment x year interaction (P = 0.05). During yr 1 through 3, SUN did not differ (P > 0.15) among treatments. However, as the stands aged, E- had a greater invasion of other plant species, which increased the CP content of the sward, thus causing heifers grazing E- during yr 5 to have greater (P < 0.01) SUN than heifers grazing E+ and EN, which did not differ (P = 0.89). Forage disappearance (DM basis) did not differ (P = 0.75) among treatments and was 4.7, 4.7, and 5.0 kg/animal daily (SEM 0.27) for E+, E-, and EN, respectively. Body weight gain per hectare was greater (P = 0.04) for E+ (257 kg) than for E- (220 kg) or EN (228 kg). In most years, animal grazing days on E+ were greater than those on E- or EN. However, in yr 5, animal grazing days did not differ (P > 0.20) among treatments. The use of stockpiled E+ as a source of low-cost winter feed is a viable option for producers, whereas grazing of EN may be more beneficial during the spring and fall, when more severe negative effects of ergot alkaloids have been observed.}, number={3}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Drewnoski, M. E. and Oliphant, E. J. and Marshall, B. T. and Poore, M. H. and Green, J. T. and Hockett, M. E.}, year={2009}, month={Mar}, pages={1034–1041} }