Effects of varying ruminally undegradable protein supplementation on forage digestion, nitrogen metabolism, and urea kinetics in Nellore cattle fed low-quality tropical forage

Citation: Batista, E. D., Detmann, E., Titgemeyer, E. C., Valadares, S. C., Valadares, R. F. D., Prates, L. L., . . . Paulino, M. F. (2016). Effects of varying ruminally undegradable protein supplementation on forage digestion, nitrogen metabolism, and urea kinetics in Nellore cattle fed low-quality tropical forage. Journal of Animal Science, 94(1), 201-216. doi:10.2527/jas2015-9493Effects of supplemental RDP and RUP on nutrient digestion, N metabolism, urea kinetics, and muscle protein degradation were evaluated in Nellore heifers (Bos indicus) consuming low-quality signal grass hay (5% CP and 80% NDF, DM basis). Five ruminally and abomasally cannulated Nellore heifers (248 +/- 9 kg) were used in a 5 x 5 Latin square. Treatments were the control (no supplement) and RDP supplementation to meet 100% of the RDP requirement plus RUP provision to supply 0, 50, 100, or 150% of the RUP requirement. Supplemental RDP (casein plus NPN) was ruminally dosed twice daily, and RUP supply (casein) was continuously infused abomasally. Jugular infusion of [(NN)-N-15-N-15]-urea with measurement of enrichment in urine was used to evaluate urea kinetics. The ratio of urinary 3-methylhistidine to creatinine was used to estimate skeletal muscle protein degradation. Forage NDF intake (2.48 kg/d) was not affected (P >= 0.37) by supplementation, but supplementation did increase ruminal NDF digestion (P < 0.01). Total N intake (by design) and N retention increased (P < 0.001) with supplementation and also linearly increased with RUP provision. Urea entry rate and gastrointestinal entry rate of urea were increased by supplementation (P < 0.001). Supplementation with RUP linearly increased (P = 0.02) urea entry rate and tended (P = 0.07) to linearly increase gastrointestinal entry rate of urea. Urea use for anabolic purposes tended (P = 0.07) to be increased by supplementation, and RUP provision also tended (P = 0.08) to linearly increase the amount of urea used for anabolism. The fraction of recycled urea N incorporated into microbial N was greater (P < 0.001) for control (22%) than for supplemented (9%) heifers. Urinary 3-methylhistidine: creatinine of control heifers was more than double that of supplemented heifers (P < 0.001). Control heifers reabsorbed a greater (P < 0.001) fraction of urea from the renal tubule than did supplemented heifers. Overall, unsupplemented heifers had greater mobilization of AA from myofibrillar protein, which provided N for urea synthesis and subsequent recycling. Supplemental RUP, when RDP was supplied, not only increased N retention but also supported increased urea N recycling and increased ruminal microbial protein synthesis

Anatomy and tectonic significance of WNW-ESE and NE-SW lineaments at a transpressive plate boundary (Nubia-Iberia)

Recent mapping of the Gulf of Cadiz seafloor permitted to identify major tectonic lineaments: the SWIM lineaments (Zitellini et al., 2009) and Cadiz lineament, striking WNW-ESE and NE-SW, respectively. Multibeam swath bathymetry and interpretation of multi-channel seismic data indicate that these features can be interpreted to correspond to the seafloor morphological expression of active dextral strike-slip faults. Based on the interpreted data and recently published GPS plate kinematic velocity vectors of Nubia with respect to Iberia and the Alboran block (e.g. Fernandes et al.; 2003 Stich et al., 2006) we propose that the SWIM Faults are related to the general NW-SE convergence of Nubia with respect to Iberia, and the Cadiz fault is related to the westward movement of the Gibraltar orogenic arc

A mutant of Metarhizium anisopliae var. acridum with enhanced submerged conidiation.

Made available in DSpace on 2018-06-06T01:01:38Z (GMT). No. of bitstreams: 1 ID278831.pdf: 343982 bytes, checksum: 1b1ebb921fe53464e93c15e17e4d406c (MD5) Previous issue date: 2007-01-16bitstream/item/178116/1/ID-27883-1.pd

Molecular determinants of improved cathepsin B inhibition by new cystatins obtained by DNA shuffling

Background: Cystatins are inhibitors of cysteine proteases. The majority are only weak inhibitors of human cathepsin B, which has been associated with cancer, Alzheimer's disease and arthritis. Results: Starting from the sequences of oryzacystatin-1 and canecystatin-1, a shuffling library was designed and a hybrid clone obtained, which presented higher inhibitory activity towards cathepsin B. This clone presented two unanticipated point mutations as well as an N-terminal deletion. Reversing each point mutation independently or both simultaneously abolishes the inhibitory activity towards cathepsin B. Homology modeling together with experimental studies of the reverse mutants revealed the likely molecular determinants of the improved inhibitory activity to be related to decreased protein stability. Conclusion: A combination of experimental approaches including gene shuffling, enzyme assays and reverse mutation allied to molecular modeling has shed light upon the unexpected inhibitory properties of certain cystatin mutants against Cathepsin B. We conclude that mutations disrupting the hydrophobic core of phytocystatins increase the flexibility of the N-terminus, leading to an increase in inhibitory activity. Such mutations need not affect the inhibitory site directly but may be observed distant from it and manifest their effects via an uncoupling of its three components as a result of increased protein flexibility.State of Sao Paulo Research Foundation (FAPESP)[1998/14138-2]State of Sao Paulo Research Foundation (FAPESP)[05/59833-5]State of Sao Paulo Research Foundation (FAPESP)[08/58316-5

As contribuições dos materiais biodegradáveis para o alcance dos Objetivos de Desenvolvimento Sustentável.

Este documento detalha as contribuições dos materiais biodegradáveis para o alcance de ODS. Assim, este texto mostra como a pesquisa científica, o desenvolvimento de novos materiais e a inovação podem contribuir para a sustentabilidade do planeta, principalmente no que tange a saúde, bem&#8209;estar dos seres vivos e à mitigação da poluição na água e na terra. Diversos materiais biodegradáveis estão presentes na vida cotidiana, como é o caso do papel e outros derivados da celulose. Entretanto, ainda é necessário grande esforço de pesquisa para formular novos materiais com alto desempenho, estudar os seus impactos no meio ambiente e também para a reduzir os custos e preços dos materiais biodegradáveis. O Brasil, como uma grande potência agropecuária, é um grande produtor de celulose e outros insumos para materiais biodegradáveis. Ainda assim, há muito espaço para crescimento do mercado de materiais biodegradáveis, para o aproveitamento de resíduos da agricultura e para a construção de uma cultura consciente que visa à redução da poluição e bem estar da população e das gerações futuras.ODS, ODS 11, ODS 12, ODS 3, ODS 6, ODS 9, ODS 14, ODS 15