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1.
J Dairy Sci ; 104(5): 5391-5404, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33663830

RESUMEN

This study evaluated the effect of harvest date and forage species on the concentration of hydroxycinnamic acids in silage and its relationship to dairy cow performance. Tall fescue and timothy were harvested at a regular date on June 27 and July 8, respectively, or at a late date on July 8 and 25, respectively, in the first regrowth. Forage was treated with a salt-based additive and ensiled in hard-pressed round bales. Forty-seven lactating dairy cows were used in a block design. Cows received 1 of 4 treatments: (1) tall fescue harvested at regular date (RTF), (2) timothy harvested at regular date (RTI), (3) tall fescue harvested at late date (LTF), and (4) timothy harvested at late date (LTI). Diets were formulated to have the same forage-to-concentrate ratio (46:54 on a dry matter basis). Harvesting at late date increased fiber components, but only for timothy, where LTI contained greater neutral detergent fiber, acid detergent fiber, and acid detergent lignin concentrations than the other silages. Concentrations of hydroxycinnamic acids were affected by forage species, where concentrations of esterified ferulic acid and p-coumaric acid were greater for tall fescue silages than for timothy silages. Cows fed the RTI diet showed the greatest intakes of dry matter, organic matter, and crude protein. Feeding diets containing timothy silages increased milk yield and energy-corrected milk yield compared with tall fescue diets when averaged over harvest dates. Cows fed the RTI diet had greater milk protein yield than cows fed the RTF and LTF diets, and milk lactose yield was greater for cows fed diets containing timothy silage compared with tall fescue silage when averaged over harvest dates. Cows fed the LTF diet showed greater urinary N excretion compared with the LTI diet, but RTI showed the lowest urinary N and urea N excretions when calculated as percent of N intake. Cows fed diets containing timothy silage excreted more uric acid than cows fed tall fescue diets. Allantoin excretion was greater for cows eating the RTI and LTI diets compared with cows eating the RTF diet. Cows fed the RTI diet had a greater estimated microbial N flow and a greater excretion of hippuric acid than the RTF and LTF groups. In conclusion, besides the effect of harvest date on increasing the fiber components of timothy, concentrations of hydroxycinnamic acids were mainly affected by forage species; consequently, milk production was only affected by forage species. This indicates that hydroxycinnamic acids, such as ferulic acid, which cross-links to glucuronoarabinoxylans, was a major factor regulating milk production of cows fed tall fescue- and timothy silage-based diets, where lower hydroxycinnamic acid concentrations were responsible for greater milk yield.


Asunto(s)
Poaceae , Ensilaje , Animales , Bovinos , Pared Celular , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Digestión , Femenino , Fermentación , Lactancia , Rumen/metabolismo , Ensilaje/análisis , Zea mays
2.
J Dairy Sci ; 102(9): 7961-7969, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31326178

RESUMEN

Our objective was to predict the dry matter intake (DMI) response during ration formulation to factors related to the filling effect of rations and their interaction with milk yield (MY) by lactating cows past peak lactation. A data set was developed consisting of 134 treatment means from 34 experiments reported in 32 peer-reviewed articles published from 1990 through 2015. The data set included data for cows ranging from 60 to 309 d postpartum with mean DMI ranging from 17.6 to 30.6 kg/d and MY ranging from 20.3 to 51.1 kg/d. Ration composition among treatments ranged from 12.7 to 21.8% of dry matter (DM) for crude protein, 11.5 to 31.0% of DM for acid detergent fiber (ADF), 25.5 to 48.2% of DM for neutral detergent fiber (NDF), 9.9 to 39.3% of DM for forage NDF (FNDF), and 0.45 to 0.84 for the ratio of ADF% to NDF% (ADF/NDF). Laboratory measures of digestibility of NDF (in vitro or in situ, FNDFD) for the sole or major forage ranged from 24.1 to 72.7%. The model included the random effect of study to account for various experiment-specific effects including different methods of measurement of NDF and FNDFD among studies. The full model also included linear and quadratic effects of crude protein, ADF, NDF, FNDF, ADF/NDF, and FNDFD, as well as their linear and quadratic interactions, and mean MY for each study and its interaction with ration factors. The proposed prediction equation is DMI (kg/d) = 12.0 - 0.107 × FNDF + 8.17 × ADF/NDF + 0.0253 × FNDFD - 0.328 × (ADF/NDF - 0.602) × (FNDFD - 48.3) + 0.225 × MY + 0.00390 × (FNDFD - 48.3) × (MY - 33.1) with mean bias = 0.00 kg/d, root mean square error = 1.55 kg/d, and concordance correlation coefficient = 0.827. Dry matter intake was positively related to MY and ADF/NDF and negatively related to FNDF, and FNDFD was positively related to DMI for cows with high MY but negatively related to MY for cows with low MY. In addition, DMI was positively related to FNDFD for low ADF/NDF but negatively related to FNDFD for high ADF/NDF. The ADF/NDF was included to represent differences in forage fragility between grasses and legumes. The proposed model was compared with the equation recommended by the National Research Council (2001) that was developed using only animal factors by fitting each equation to a subset of the data set that included the required inputs for both. The National Research Council (2001) equation without diet factors had a higher root mean square error and over-predicted DMI at high DMI and under-predicted DMI at low DMI. Our proposed equation should be useful to predict DMI response to factors related to the filling effects of rations during ration formulation.


Asunto(s)
Alimentación Animal , Bovinos/fisiología , Alimentación Animal/análisis , Animales , Industria Lechera , Dieta/veterinaria , Fibras de la Dieta , Femenino , Lactancia , Leche , Modelos Biológicos , Poaceae , Periodo Posparto
3.
J Dairy Sci ; 101(7): 5890-5901, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29680654

RESUMEN

Feed intake assessment is a valuable tool for herd management decisions. The use of markers, either internal or external, is currently the most used technique for estimating feed intake in production animals. The experiment used 10 multiparous Holstein cows fed a corn silage-based diet, with 55:45 forage-to-concentrate ratio, the average fecal recovery (FR) of TiO2 was higher than FR of Cr2O3, and both FR were more than unity. With internal markers, acetyl bromide lignin and cutin FR were lower than unity, and average FR for indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) was 1.5. The FR was unaffected by the fecal sampling procedure and appears to be an intrinsic property of each molecule and how it interacts with digesta. Of the 2 external markers, only Cr2O3 produced accurate fecal output (FO) estimates and the same happened to dry matter digestibility (DMD) when iNDF and iADF were used. Estimates for DMD and FO were affected by sampling procedure; 72-h bulk [sub-sample from total feces collection (TFC)] sampling consistently produced accurate results. The grab (sub-samples taken at specific times during the day) sampling procedures were accurate when using either of the indigestible fibers (iNDF or iADF) to estimate DMD. However, grab sampling procedures can only be recommended when concomitant TFC is performed on at least one animal per treatment to determine FR. Under these conditions, Cr2O3 is a suitable marker for estimating FO, and iNDF and iADF are adequate for estimating DMD. Moreover, the Cr2O3+iADF marker pair produces accurate dry matter intake estimates and deserves further attention in ruminant nutrition studies. The method of dosing the external markers is extremely important and greatly affects and determines results. Whichever the method, it must allow the animals to display normal feeding behavior and not affect performance. The grab sampling procedures can replace TFC (once FR is established), which may open new possibilities for pasture-based or collectively housed animals.


Asunto(s)
Alimentación Animal , Biomarcadores/análisis , Bovinos/metabolismo , Heces/química , Zea mays , Animales , Dieta , Fibras de la Dieta/administración & dosificación , Digestión , Femenino , Lactancia , Rumen , Ensilaje
4.
Arq. bras. med. vet. zootec. (Online) ; 70(2): 554-562, mar.-abr. 2018. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-910710

RESUMEN

The objective of this study was to evaluate the effects of Brachiaria brizantha cv. Marandu syn. Urochloa brizantha cv. Marandu (Marandu palisadegrass) in late winter on pasture structure, apparent selectivity, and sheep production during spring and early summer. The conditions of deferred pastures at the end of winter were: low (15.1cm and 4600kg/ha of DM), medium (23.2cm and 5940kg/ha of DM), high (31.4cm and 7640kg/ha of DM) and high/mowed (31.3cm and 7200kg/ha of DM, mowed to 8cm). The experiment was conducted in split plot design (sward conditions at the end of winter: low, medium, tall and tall/lowered) during time (early, middle and late spring/summer) and completely randomized design with three replications. The percentages of live leaf laminae in available forage and in simulated grazing samples were higher in tall/lowered sward and lower in high sward, oppositely to percentage of dead tissue. Only at the beginning of the grazing period the high/lowered sward had lower forage mass and bulk density. This remained high in high sward during all the grazing period. The sheep performance and the animal production per area were higher in low sward and lower in tall swards. The low sward has better structure and higher sheep production starting at spring. The lower of the marandu palisade grass at late winter improves this structure and increases sheep production during spring and early summer.(AU)


Objetivou-se avaliar os efeitos da condição do pasto diferido de Brachiaria brizantha cv. Marandu syn. Urochloa brizantha cv. Marandu (capim-marandu) no fim do inverno sobre a estrutura do pasto, a seletividade aparente e a produção de ovinos durante a primavera e o início do verão. As condições dos pastos diferidos no fim do inverno foram: baixo (15,1cm e 4.600kg/ha de MS), médio (23,2cm e 5.940kg/ha de MS), alto (31,4cm e 7.640kg/ha de MS) e alto/roçado (31,3cm e 7.200kg/ha de MS, rebaixado para 8cm). O experimento foi conduzido em esquema de parcela (condições dos pastos ao fim do inverno: baixo, médio, alto e alto/roçado) subdividida no tempo (início, meio e fim da primavera/verão) e delineamento inteiramente ao acaso, com três repetições. Os percentuais de lâmina foliar viva na forragem disponível e na amostra de simulação de pastejo foram maiores no pasto alto/roçado e menores no pasto alto, contrariamente ao percentual de tecido morto. Apenas no início do período de pastejo, o pasto alto/roçado apresentou menores massa e densidade volumétrica de forragem. Esta se manteve alta no pasto alto durante todo o período de pastejo. No início do período de pastejo, os pastos apresentaram pior composição morfológica na FD. O desempenho dos ovinos e a produção animal por área foram maiores no pasto baixo e menores no pasto alto. O pasto baixo, no fim do inverno, apresenta melhor estrutura e maior produção de ovinos a partir da primavera. A roçada do pasto de capim-marandu no fim do inverno melhora sua estrutura e aumenta a produção animal durante a primavera e o início do verão.(AU)


Asunto(s)
Animales , Pastizales/análisis , Ovinos/metabolismo , Brachiaria
5.
N Biotechnol ; 39(Pt A): 99-109, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27737801

RESUMEN

Various plant species have long been used in traditional medicine worldwide to treat diabetes. Among the plant-based compounds with hypoglycemic properties, studies on insulin-like proteins isolated from leaves, fruits and seeds are rarely reported in the relevant literature. Our research group has been investigating the presence of insulin-like proteins in Moringa oleifera, a plant species native to India, and we have obtained a leaf protein isolate and semi-purified derived fractions, as well as a seed coat protein fraction (Mo-SC), with hypoglycemic activity in chemically induced diabetic mice that have increased tolerance to orally administered glucose. Equally importantly, Mo-SC possesses insulin-like antigenic epitopes. In this context, the present review aims to highlight that prospection of insulin-like proteins in plants is of the utmost importance both for finding new drugs for the treatment of diabetes and for shedding light on the mechanisms involved in diabetes.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Insulina/uso terapéutico , Moringa oleifera/química , Proteínas de Plantas/uso terapéutico , Secuencia de Aminoácidos , Animales , Humanos , Insulina/química , Insulina/aislamiento & purificación , Lectinas/uso terapéutico , Hojas de la Planta/química , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación
6.
J Surg Case Rep ; 2017(9): rjx184, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29423166

RESUMEN

Leak following laparoscopic sleeve gastrectomy is one of the most feared complications and its management can be difficult and frustrating for patients and physicians involved. Using multimodality approach and having variable options to plan management for patients presenting with leak following bariatric surgery can be advantageous for physicians. The use of endoscopic injection of EpiFix-dehydrated Human Amnion/Chorion Membrane (dHACM) allograft can be a novel adjunct in facilitating healing of the leak site by iatrogenic introduction of tissue growth factors, cytokines and building connective tissue matrix.

7.
Arq. bras. med. vet. zootec ; 68(6): 1655-1663, nov.-dez. 2016. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-827916

RESUMEN

Objetivou-se compreender o efeito do período de diferimento sobre a seletividade aparente de bovinos pelos componentes morfológicos e de valor nutritivo do pasto de Brachiaria decumbens cv. Basilisk. Adotaram-se o esquema de parcela subdividida e o delineamento em blocos ao acaso com duas repetições. Foram estudados quatro períodos de diferimento (73, 103, 131 e 163 dias) e duas amostras de forragem (disponível na pastagem (DP) e obtida pela simulação de pastejo (SP)). As percentagens de lâmina foliar viva (LFV), matéria seca potencialmente digestível (MSPD) e proteína bruta (PB) foram maiores na amostra de SP, quando esta foi comparada à forragem DP. Padrão de resposta contrário ocorreu com os percentuais de colmo vivo (CV), colmo morto (CM) e fibra em detergente neutro (FDN). De modo geral, o maior período de diferimento resultou em pior composição morfológica e valor nutritivo das forragens. Os índices de seletividade aparente (ISA) da LFV, do CV e da lâmina foliar morta (LFM) aumentaram linearmente com o período de diferimento. O ISA do CM apresentou maiores valores em pastos sob períodos intermediários de diferimento. Com o aumento do período de diferimento, os ISA da FDN e da MSPD permaneceram constantes, os ISP da FDN potencialmente digestível e da PB reduziram linearmente, e o ISP da FDN indigestível incrementou de maneira linear. O ISA permite a compreensão da seletividade dos componentes morfológicos e das entidades nutricionais do pasto pelos bovinos. A redução do período de diferimento melhora a estrutura do pasto e otimiza a seletividade dos bovinos.(AU)


The experiment was carried out aiming to understand the effect of deferring period on morphology and nutritive value of Brachiaria decumbens cv. Basilisk pasture and on hand-plucking sample with cattle. Subdivided plots were used according to a randomized block design with two replicates. Four deferring periods (73, 103, 131 and 163 days) and two forage samples (available in pasture (AP) and obtained by hand-plucking (HP)) were studied. The live leaf laminae (LLL), potentially digestible dry matter (PDDM) and crude protein (CP) percentages were higher in HP samples, when compared to AP forage. The opposite response pattern occurred for live stem (LS), dead stem (DS) and neutral detergent fiber (NDF) percentages. In general, the longest deferring period resulted in a worse morphological composition and nutritive value of forages. The potential selectivity index (PSI) of LLL, LS and dead leaf lamina (DLL) increased linearly with deferring period. The PSI of DS was highest in grasslands under interim deferring periods. With increase in deferring period, the PSI of the NDF and PDDM remained constant, the PSI of potentially digestible NDF and CP decreased linearly and the PSI of indigestible NDF increased linearly. The PSI allows the understanding of selectivity of morphological components and nutritional entities for cattle grazing. The deferring period reduction improves the sward structure and optimizes the cattle selectivity.(AU)


Asunto(s)
Animales , Bovinos , Brachiaria , Conducta Alimentaria , Valor Nutritivo , Pastizales
8.
J Anim Sci ; 92(12): 5622-34, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25414108

RESUMEN

Fiber digestibility is an important factor regulating DMI in ruminants. Additionally, the ensiling process can also affect digestibility and chemical composition of the forage. The objective of this study was to investigate effects of sugarcane NDF digestibility (NDFD) and conservation method on intake, rumen kinetics, and the ruminal ecosystem of steers. Eight ruminally cannulated Nellore steers (275±22 kg BW) were used in a replicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Two sugarcane genotypes divergent for stalk NDFD were used: IAC86-2480 with high NDFD and SP91-1049 with low NDFD. Experimental diets were formulated with 40% sugarcane, either freshly cut or as silage, and 60% concentrate on a DM basis. Each experimental period lasted for 14 d, with the last 4 d used for determination of intake, ruminal evacuation, and ruminal fluid collection. The effect of fiber digestibility on DM and NDF intake was dependent on the forage conservation method (P=0.01). High NDFD increased (P<0.01) DMI only when sugarcane was offered as silage, having no effect (P=0.41) on DMI when offered as freshly cut. Conservation method had no effect on total ruminal mass, with only a tendency (P<0.10) for greater NDF and indigestible NDF ruminal mass in steers fed the low-NDFD genotype. The NDF turnover and passage rates were greater (P<0.05) for the genotype with high NDFD but only when offered as silage. Liquid turnover rate in the rumen was greater (P=0.02) for diets containing silage, with no effect of genotype (P=0.87). There was no effect of NDFD genotype on ruminal pH (P=0.77); however, diets containing sugarcane as silage increased (P<0.01) ruminal pH. Total concentration of short chain fatty acids (P=0.05) and proportions of propionate (P=0.01) were greater for diets containing fresh sugarcane. Diets with fresh sugarcane increased the ruminal population of Streptococcus bovis (P<0.01) and Ruminococcus albus (P=0.03). The relative population of R. albus was also greater (P=0.04) for diets containing the sugarcane genotype with high NDFD. Feeding diets containing the sugarcane genotype with high NDFD increased Fibrobacter succinogenes population but only when sugarcane was fed as freshly cut (P=0.02). Using sugarcane genotypes with high NDFD can increase intake and benefit fiber-degrading bacteria in the rumen.


Asunto(s)
Regulación del Apetito/efectos de los fármacos , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Fibras de la Dieta/farmacología , Digestión/efectos de los fármacos , Rumen/metabolismo , Amoníaco/metabolismo , Alimentación Animal/análisis , Animales , Ácidos Grasos Volátiles/metabolismo , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Masculino , Distribución Aleatoria , Rumen/microbiología , Ruminococcus/aislamiento & purificación , Saccharum/metabolismo , Ensilaje/análisis , Streptococcus bovis/aislamiento & purificación
9.
Toxicon ; 51(6): 952-63, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18328522

RESUMEN

SBTX, a novel toxin from soybean, was purified by ammonium sulfate fractionation followed by chromatographic steps DEAE-Cellulose, CM-Sepharose and Superdex 200 HR fast-protein liquid chromatography (FPLC). Lethality of SBTX to mice (LD(50) 5.6 mg/kg) was used as parameter in the purification steps. SBTX is a 44-kDa basic glycoprotein composed of two polypeptide chains (27 and 17 kDa) linked by a disulfide bond. The N-terminal sequences of the 44 and 27kDa chains were identical (ADPTFGFTPLGLSEKANLQIMKAYD), differing from that of 17 kDa (PNPKVFFDMTIGGQSAGRIVMEEYA). SBTX contains high levels of Glx, Ala, Asx, Gly and Lys and showed maximum absorption at 280 nm, epsilon(1cm)(1%) of 6.3, and fluorescence emission in the 290-450 nm range upon excitation at 280nm. The secondary structure content was 35% alpha-helix, 13% beta-strand and beta-sheet, 27% beta-turn, 25% unordered, and 1% aromatic residues. Immunological assays showed that SBTX was related to other toxic proteins, such as soyatoxin and canatoxin, and cross-reacted weekly with soybean trypsin inhibitor and agglutinin, but it was devoid of protease-inhibitory and hemagglutinating activities. The inhibitory effect of SBTX on growth of Cercospora sojina, fungus causing frogeye leaf spot in soybeans, was observed at 50 microg/ml, concentration 112 times lesser than that found to be lethal to mice. This effect on phytopathogenic fungus is a potential attribute for the development of transgenic plants with enhanced resistance to pathogens.


Asunto(s)
Antifúngicos/farmacología , Glycine max/toxicidad , Glicoproteínas/aislamiento & purificación , Glicoproteínas/toxicidad , Hemaglutinación/efectos de los fármacos , Hongos Mitospóricos/efectos de los fármacos , Proteínas de Soja/aislamiento & purificación , Proteínas de Soja/toxicidad , Secuencia de Aminoácidos , Animales , Cromatografía en Gel/métodos , Cromatografía Liquida/métodos , Electroforesis en Gel de Poliacrilamida , Glicoproteínas/química , Hemaglutinación/fisiología , Ratones , Hongos Mitospóricos/crecimiento & desarrollo , Datos de Secuencia Molecular , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/toxicidad , Estructura Secundaria de Proteína , Proteínas de Soja/química , Glycine max/química , Análisis Espectral , Toxinas Biológicas/química , Toxinas Biológicas/toxicidad
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