Fluxo de proteína do rumen para o duodeno de novilhos alimentados com dieta volumosa e dieta concentrada.

Quatro novilhos fistulados foram usados para comparar o efeito da dieta no fluxo duodenal de N e aminoacidos (AA)

Ruminal digestion of protein and fiber in duodenally canmilated cows treated with vitaferm.

Ruminal digestion of protein and fiber in duodenally canmilated cows treated with vitaferm

Automated long-term total collection versus indicator method to estimate duodenal digesta flow in cattle.

Automated longterm total collection versus indicator method to estimated duodenal digesta flow in cattle

Recycled nitrogen in lactating dairy cows fed high and low grain diets.

Recycled N used by rumen bacteria and reaching the small intestine was studied in 4 duodenally cannuled lactating cows fed diets of 2:1 (C) and 1:2 (F) concentrate to forage

Impacts of a Post-Transport/Pre-Processing Rest Period on the Growth Performance and Serum Metabolites of Cattle Entering a Feedlot

Objective: The objective of this study was to evaluate the impact of a post-transport rest period on receiving calf growth performance and blood serum metabolites as indicators of immune function. Study Description: Eighty heifers were purchased from a sale barn and transported 6 hours to the Kansas State University Beef Cattle Research Center where they were processed at one of four times: immediately upon arrival or after a 6-, 24-, or 48-hour rest period. Cattle were then fed for 35 days with growth performance data collected weekly. Blood samples were also collected and analyzed for serum infectious bovine rhinotracheitis (IBR) titer and biochemical parameters. Results: Processing time did not impact (P \u3e 0.05) heifer average daily gain. Overall, dry matter intake (DMI) decreased linearly (P = 0.027) as the rest time increased. The number of days for heifers to reach a targeted DMI of 2.5% body weight was linearly increased (P = 0.023) as time of rest increased. Serum IBR titer for heifers processed at either 0 or 6 hours upon arrival was higher (P \u3c 0.01) on day 35 compared to day 0. This response was expected, as these cattle were vaccinated immediately or shortly after arrival. Interestingly, no difference in IBR titer was observed (P \u3e 0.05) between day 0 and day 35 for heifers processed at either 24 or 48 hours upon arrival, indicating potential seroconversion of IBR antibodies before vaccination. The Bottom Line: These results indicate that rest time after arrival and prior to processing may not affect calf growth performance, but there is evidence that a 6-hour rest period could maximize DMI upon arrival to a feedlot. Additional research with greater replication and more industry-standard experimental conditions should be conducted to further evaluate these parameters

Portal drained visceral flux, hepatic metabolism, and mammary uptake of free and peptide-bound amino acids and milk amino acid output in dairy cows fed diets containing corn grain steam flaked at 360 orsteam rolled at 490 g/L.

Objectives were to measure net fluxes of free (FAA) and peptide bound amino acids (AA) (PBAA) across portal-drained viscera (PDV), liver, splanchnic, and mammary tissues, and of milk AA output of lactating Holstein cows (n = 6, 109 +/- 9 d in milk) as influenced by flaking density of corn grain. Cows were fed alfalfa-based total mixed ration (TMR) containing 40% steam-flaked (SFC) or steam-rolled corn (SRC) grain. The TMR were offered at 12-h intervals in a crossover design. Six sets of blood samples were obtained from indwelling catheters in portal, hepatic, and mammary veins and mesenteric or costoabdominal arteries every 2 h from each cow and diet. Intake of dry matter (18.4 +/- 0.4 kg/d), N, and net energy for lactation were not altered by corn processing. Milk and milk crude protein yields (kg/12-h sampling) were 14.2 vs. 13.5 and 0.43 vs. 0.39 for cows fed SFC or SRC, respectively. The PDV flux of total essential FAA was greater (571.2 vs. 366.4 g/12 h, SEM 51.4) in cows fed SFC. The PDV flux of total essential PBAA was 69.3 +/- 10.8 and 51.5 +/- 13.2 g/12 h for cows fed SFC and SRC, respectively, and differed from zero, but fluxes of individual PBAA rarely differed between treatments. Liver flux of essential FAA was greater in cows fed SRC, but only the PBAA flux in cows fed SRC differed from zero. Splanchnic flux of FAA and PBAA followed the pattern of PDV flux, but variation was greater. Mammary uptake (g/12 h) of total essential FAA was greater in cows fed SFC than SRC (224.6 vs. 198.3, SEM 7.03). Mammary uptake of essential PBAA was 25.0 vs. 15.1, SEM 5.2, g/12 h for cows fed SFC or SRC, respectively, and differed from zero in half of the PBAA. Milk output of EAA was 187.8 vs 175.4, SEM 4.4 g/12 h in cows fed SFC and SRC, respectively, and output of most essential AA consistently tended to be greater in cows fed SFC. It is apparent that PBAA comprise a portion of total AA flux across PDV and are affected by grain processing. Further, this pool supplies an important component of AA taken up by the mammary gland. Quantifying the contribution of PBAA may improve diet formulation with respect to intestinal absorption and mammary uptake of AA

Multiwavelength studies of MHD waves in the solar chromosphere: An overview of recent results

The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly investigate the role waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.Comment: 48 pages, 25 figures, accepted into Space Science Review

Sensory Input Pathways and Mechanisms in Swallowing: A Review

Over the past 20 years, research on the physiology of swallowing has confirmed that the oropharyngeal swallowing process can be modulated, both volitionally and in response to different sensory stimuli. In this review we identify what is known regarding the sensory pathways and mechanisms that are now thought to influence swallowing motor control and evoke its response. By synthesizing the current state of research evidence and knowledge, we identify continuing gaps in our knowledge of these mechanisms and pose questions for future research