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One of the most intriguing discoveries of Juno is the quasi‐systematic detection of upgoing electrons above the auroral regions. Here we discuss a by‐product of the most energetic component of this population: a contamination resembling bar codes in the Juno‐UVS images. This pattern is likely caused by bursts of ∼10 MeV electrons penetrating the instrument. These events are mostly detected when Juno's magnetic footprint is located poleward of the main emission relative to the magnetic pole. The signal is not periodic, but the bursts are typically  0.1–1 s apart. They are essentially detected when Juno‐UVS is oriented toward Jupiter, indicating that the signal is due to upgoing electrons. The event detections occur between 1 and 7 Jovian radii above the 1‐bar level, suggesting that the electron acceleration takes place close to Jupiter and is thus both strong and brief. Someone's noise is always someone else's signal. Here we use the Juno‐UVS ultraviolet spectrograph on board the Juno spacecraft as a particle detector rather than a photon collector. We analyze artifacts looking like a bar code in ultraviolet images of Jupiter's aurora to investigate a very specific kind of radiation above the poles. These bar code events are caused by very sporadic bursts of relativistic electrons arising from the aurora itself, rather than the radiation belts. This indicates the existence of a very efficient mechanism accelerating electrons upward right above Jupiter's atmosphere. Rapidly varying noise caused by ∼10 MeV penetrating electrons creates bar codepatterns in Juno‐UVS dataThe typical timescale is ∼0.1‐1 sThe magnetic footprints of these bar code events are mostly located poleward of the main auroral emission relative to the magnetic pole

Changes in mammary gland histology, dry weights, nucleic acids and in vitro rates of substrate oxidation and incorporation into lipid were measured in mammary biopsies of three gilts each on d 30, 45, 60, 75, 90, 105 and 112 of pregnancy, and d 1 and 4 of lactation. Histological changes noted were progressive duct growth early in pregnancy followed by rapid lobulo-alveolar development between d 75 and 90 to complete mammogenesis. Colostrum and lipid were evident by d 105 with marked distension of alveolar lumina on d 112. Complete differentiation of the secretory process was apparent on the day of parturition. Concentration of dry, fat-free tissue (DFFT) and DNA changed little before d 60 but increased fourfold between d 75 and 90. No further increases in DFFT or DNA were noted. RNA concentrations paralleled DNA through d 90, after which they steadily increased. Rates of acetate and glucose oxidation increased transiently during midpregnancy then declined and remained low until initiation of lactogenesis. Substrate incorporation into lipid increased slightly at midpregnancy and again at d 105, after which it increased markedly. Collectively, results indicate that mammogenesis is complete by d 90, after which lactogenesis is initiated in a two-stage process. Metabolic rates expressed on a DNA basis indicated considerable rates of oxidation, but not of lipogenesis by proliferating mammary tissue. Preferential metabolism of acetate vs glucose near parturition suggests coordination of metabolism between the mammary gland and other maternal tissues.

An 83-day feeding trial was conducted with 32 steers to evaluate the effect of including 0 or 33 g monensin per metric ton in diets containing either dried citrus pulp or corn as a main energy source and either cage layer manure or soybean meal as a source of supplemental nitrogen. Steers averaged 259 kg initially. A 2 × 2 × 2 factorial arrangement of dietary treatments was used. No influence of monensin or dietary energy sources on body weight gain of animals was observed. However, steers fed soybean meal gained faster (P<.01) than those fed cage layer manure. Monensin reduced daily feed intake from 9.21 to 8.20 kg/head and decreased feed to gain ratio from 8.42 to 7.22. Carcass evaluation revealed no effect of treatment on quality grade, but dressing percentage and yield grade for steers fed soybean meal were higher (P<.05) than those for steers fed cage layer manure. Feeding cage layer manure at the 20% level increased (P<.01) Ca in kidney and Cu in liver and decreased (P<.01) Mn in liver. Including citrus pulp in the diets increased Zn (P<.01) in muscle and Fe (P<.05) in kidney and decreased (P<.01) liver Mn. A second, 64-day experiment was conducted with 32 steers to determine the effect of including monensin (33 g/metric ton) in diets containing either dried citrus pulp or corn as the main energy source. Steers averaged 400 kg initially. A 2 × 2 factorial arrangement of dietary treatments was used. Daily weight gain was not affected by treatments. Monensin decreased (P<.01) daily feed intake from 11.50 to 9.91 kg/head and decreased (P<.05) feed to gain ratio from 11.07 to 10.16. Monensin increased (P= .03) ruminal propionic acid concentration and decreased (P<.01) acetic acid to the same extent whether the primary energy source was corn or dried citrus pulp. There was no influence of treatments on dressing percentage, quality grade or yield of carcasses.

Twenty-four steers, initially averaging 256 kg, were used in a 2 × 3 factorial arrangement of treatments to determine the effect of monensin (22 g/metric ton) in combination with three levels (0, 12.5 and 25.0%) of cage layer manure as a replacement for soybean meal in finishing diets. Average daily gains for 0, 12.5 and 25.0% cage layer manure with and without monensin were: .99, 1.04, .90 kg and 1.03, .86, 1.01 kilograms. Feed intake and feed conversion were not affected by any treatment. Ruminal propionic acid concentration averaged 50.5, 42.8, 36.0 moles/100g with monensin and 37.3, 30.5, 26.6 moles/100g without monensin (P<.01) for 0, 12.5, 25.0% cage layer manure, respectively. Carcass evaluation revealed no significant differences in quality or yield grades, dressing percentage, or flavor and juiciness of broiled steaks. Addition of cage layer manure increased Ca (P<.01) in muscle, Cu (P<.01) in liver and Mg (P<.01) and P (P<.05) in kidney, but decreased (P<.05) Fe in kidney. Arsenic in kidney and muscle increased (P<.05) when cage layer manure was fed, but levels of As, Pb, Cd and Hg did not accumulate to a level that may be harmful to ruminants. A metabolism study was performed in a 2 × 2 factorial arrangement of treatments to evaluate the effect of 33 g monensin/metric ton on nitrogen utilization in 32 wether lambs fed diets containing cage layer manure or soybean meal as sources of nitrogen When compared to the controls, monensin decreased (P<.01) fecal nitrogen excretion (9.6 vs9.0 g/head daily), and increased (P<.01) digestibility of nitrogen (45.3 vs48.4%) and urinary excretion (6.8 vs7.1 g/head daily). Lambs fed soybean meal had a higher (P<.01) nitrogen digestibility (40.9 vs52.9%) than did cage layer manure-fed lambs. Nitrogen retention was not affected by treatment.

Forty steers averaging 282 kg initially were allotted randomly to four treatment groups, with two replicates each, in a 2 × 2 factorial arrangement of diet treatments to determine the effect of 0 and 200 mg monensin per head daily and two levels of energy supplementation when cottonseed hulls were fed ad libitumfor 126 days. The animals were continued an additional 6 days to obtain luminal fluid samples. The two supplements, consisting of combinations of soybean meal, corn meal, minerals and vitamins were fed once daily to provide either 1.4 or 2.2 kg/head, and an isonitrogenous supplemental intake of 643 g crude protein/head daily. Average daily gain (ADG), daily total feed intake (FI), and total feed required per unit gain (F:G) for the low energy supplement with and without monensin and the high energy supplement with and without monensin were ADG, .83, .78, .89, .81 kg; FI, 11.85, 12.87, 11.66, 12.11 kg; F:G, 14.35, 16.49, 13.09, 15.03, respectively. Average daily gain was not affected (P>.10) by treatment. Monensin decreased daily FI (P <.01) and improved F:G (P=.02). Steers fed the low energy supplement consumed more total feed (P=.03) than those fed the high energy supplement (12.36 vs11.88 kg/head daily). Ruminal propionic acid, at 9 and 28 hr after feeding supplements decreased (P<.01) from 18.4 and 12.7 moles/100g with monensin to 13.5 and 10.7 moles/100g without monensin. Propionic acid concentration at 9 hr after supplementation was increased (P<.01) by higher supplemental energy but not at 28 hours.

Feeding studies with steers were conducted to evaluate two samples (A and B) of sugarcane condensed molasses solubles (CMS) as a feedstuff for ruminants. The CMS contained 53.3 and 52.6% dry matter (DM) and, on a DM basis, 23.8 and 32.6% ash and 10.2 and 8.7% crude protein for samples A and B, respectively. In Exp. 1 (CMS A) and 2 (CMS B), 40 yearling steers were fed 0, 5, 10 or 15% of CMS (DM basis) substituted for corn and(or) soybean meal irk a concentrate diet for 56 d. Steers from Exp. 2 were fed an additional 28 d except that steers consuming 15% CMS were changed to the basal diet due to poor performance. Reduced daily gains and less efficient feed conversion (P<.05) occurred when steers were fed CMS in excess of 5% of diet DM. Carcass characteristics were unaffected by treatment. Ruminal propionic acid concentration was decreased (P<.05) for diets containing 10 or 15% CMS. Butyric acid was increased (P<.05) for all levels of CMS. Liver Zn decreased (P<.05) and kidney Mn increased (P<.05) as dietary CMS increased. Muscle Fe was also elevated (P<.05) by CMS. The CMS had less value than corn as an ingredient in diets for finishing cattle. The studies suggest that sugarcane CMS should not be used in diets intended to promote maximum gains.