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1.
J Dairy Sci ; 103(8): 7451-7461, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32448574

RESUMEN

Objectives were to evaluate the effects of rumen-protected glucose (RPG) supplementation on milk production, post-absorptive metabolism, and inflammatory biomarkers in transition dairy cows. Fifty-two multiparous cows were blocked by previous 305-d mature-equivalent milk (305ME) yield and randomly assigned to 1 of 2 iso-energetic and iso-nitrogenous treatments: (1) control diet (CON; n = 26) or (2) a diet containing RPG (pre-fresh 5.3% of dry matter and 6.0% of dry matter postpartum; n = 26). Cows received their respective dietary treatments from d -21 to 28 relative to calving, and dry matter intake was calculated daily during the same period. Weekly body weight, milk composition, and fecal pH were recorded until 28 d in milk (DIM), and milk yield was recorded through 105 DIM. Blood samples were collected on d -7, 3, 7, 14, and 28 relative to calving. Data were analyzed using repeated measures in the MIXED procedure (SAS Institute Inc., Cary, NC) with previous 305ME as a covariate. Fecal pH was similar between treatments and decreased (0.6 units) postpartum. Dry matter intake pre- and postpartum were unaffected by treatment, as was milk yield during the first 28 or 105 DIM. Milk fat, protein, and lactose concentration were similar for both treatments. Blood urea nitrogen and plasma glucose concentrations were unaffected by treatment; however, results showed increased concentration of circulating insulin (27%), lower nonesterified fatty acids (28%), and lower postpartum ß-hydroxybutyrate (24%) in RPG-fed cows. Overall, circulating lipopolysaccharide-binding protein and haptoglobin did not differ by treatment, but at 7 DIM, RPG-fed cows had decreased lipopolysaccharide-binding protein and haptoglobin concentrations (31 and 27%, respectively) compared with controls. Supplemental RPG improved some biomarkers of post-absorptive energetics and inflammation during the periparturient period, changes primarily characterized by increased insulin and decreased nonesterified fatty acids concentrations, with a concomitant reduction in acute phase proteins without changing milk production and composition.


Asunto(s)
Alimentación Animal , Enfermedades de los Bovinos/sangre , Glucosa/farmacología , Inflamación/veterinaria , Ácido 3-Hidroxibutírico/sangre , Animales , Peso Corporal , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Grasos no Esterificados/sangre , Femenino , Glucosa/metabolismo , Inflamación/sangre , Inflamación/tratamiento farmacológico , Insulina/sangre , Lactancia/efectos de los fármacos , Lactosa/análisis , Lactosa/metabolismo , Leche , Rumen/metabolismo
2.
J Dairy Sci ; 102(1): 377-387, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30415859

RESUMEN

Although it is recommended to offer free drinking water (called drinking water hereafter) immediately after birth, producers wait, on average, 17 d to first offer drinking water to newborn dairy calves. The objective of this study was to examine water and feed intake, growth performance, health status, and nutrient digestibility of Holstein heifer calves offered drinking water from birth (W0) as compared with those offered it at 17 d of age (W17), when fed an ad libitum volume of milk. Thirty Holstein heifer calves, balanced for parity of the dam, birth weight, and birth week, were randomly assigned (n = 15) to W0 or W17. Calves had free access to drinking water and a starter ration, offered in 2 separate buckets, until they were 70 d of age. Calves were bottle-fed with pasteurized whole milk 3× per day (2.0 kg/feeding until d 14, and 3.2 kg/feeding thereafter). Calves were partially weaned (33% of the milk allowance 1 × per day) at 42 d of age and completely weaned at 49 d of age. Drinking water intake, starter intake, milk intake, ambient temperature, and the fecal consistency were recorded daily. Body weight, hip height, hip width, heart girth, and body length were measured weekly. Blood (drawn from a jugular vein) was analyzed for hematocrit and haptoglobin concentrations at 14 d of age. On d 69 and 70, total fecal output of individual calves was measured and analyzed for chemical composition to determine apparent total-tract digestibility of nutrients. When offered from birth, newborn calves consumed 0.75 ± 0.05 kg/d water aside from the water they received from ad libitum milk allowance during the first 16 d. Once offered, W17 calves drank more water (59%) than W0 calves during the preweaning period. Starter intake of W0 and W17 calves was similar, but W0 calves consumed 0.285 kg/d more milk and tended to achieve greater body weight and heart girth compared with W17 calves during the preweaning period. Offering water from birth versus offering it later did not affect the number of days with diarrhea, intensity of diarrhea, or blood hematocrit and haptoglobin concentrations of preweaned calves. Despite a similar starter intake, W0 calves had greater hip height, body length, apparent total-tract digestibility of acid detergent fiber and neutral detergent fiber, and feed efficiency than W17 calves postweaning (50 to 70 d of age). When followed up to 5 mo of age, W0 calves had greater body weight than W17 calves. Provision of drinking water immediately after birth could improve growth and development of calves pre- and postweaning, potentially by stimulating rumen development, thus increasing nutrient availability.


Asunto(s)
Bovinos/fisiología , Dieta , Agua Potable , Ingestión de Líquidos , Nutrientes/metabolismo , Alimentación Animal/análisis , Animales , Peso Corporal , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Femenino , Distribución Aleatoria , Rumen/metabolismo , Destete
3.
Am Surg ; 64(4): 298-301, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9544136

RESUMEN

Gallbladder diverticulum is an unusual and uncommon disease process rarely discussed in the literature. This disorder may not be diagnosed until surgically resected. The presentation may entail nonspecific complaints over a prolonged period as highlighted in a case report of a 17-year-old woman with this disease. The incidence and pathophysiology of this disease process is correlated to the symptoms and signs of this patient. The surgical findings, procedure, and outcome are described.


Asunto(s)
Divertículo/diagnóstico , Divertículo/cirugía , Enfermedades de la Vesícula Biliar/diagnóstico , Enfermedades de la Vesícula Biliar/cirugía , Dolor Abdominal/etiología , Adolescente , Colecistectomía Laparoscópica , Divertículo/complicaciones , Divertículo/fisiopatología , Femenino , Enfermedades de la Vesícula Biliar/complicaciones , Enfermedades de la Vesícula Biliar/fisiopatología , Humanos , Tomografía Computarizada por Rayos X
4.
Theriogenology ; 49(4): 813-22, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10732089

RESUMEN

The objective of the experiment was to determine whether passive immunization against inhibin at weaning would increase FSH secretion and thereby influence postweaning reproductive performance in sows. Commercial Yorkshire sows (n = 173) were assigned within parity to 5 alpha-inhibin fragment antibody (alpha-IF-Ab) dosage groups: 0 (control), 3.25, 6.5, 13 and 26 RP-2 kU/kg alpha-IF-Ab. Antibody had been semipurified from ovine antisera raised against alpha-IF, a peptide that mimicked the N-terminal region of inhibin's alpha-subunit. A RP-2 U refers to a laboratory reference preparation. Sows were administered a single intramuscular injection of control solution or alpha-IF-Ab just before 21-d-old piglets were weaned. Blood samples were taken immediately before immunization and 24 h later. Sows were bred upon expression of estrus. Serum alpha-IF-Ab titers in sows 24 h following passive immunization increased (P < 0.001) with dosage. In control sows serum FSH concentrations decreased 24% by 24 h postweaning (P < 0.001). The decrease was diminished or prevented by alpha-IF-Ab treatment in a dose-responsive manner (P < 0.001). Most (167/173) sows were bred within 10 d postweaning, and wean-to-service intervals tended (P < 0.1) to be shorter in the 13 and 26 RP-2 kU/kg alpha-IF-Ab dosage groups. Farrowing rate was 72% (124/173) and was similar among sows in the alpha-IF-Ab dosage groups. Litter size, expressed as total or live piglets born per sow or per sow farrowed, was unchanged by alpha-IF-Ab treatment. Results demonstrate that 1) inhibin plays a key role in regulating FSH secretion at weaning, and 2) blocking the acute postweaning drop in FSH secretion has little if any effect on subsequent reproductive performance.


Asunto(s)
Anticuerpos/farmacología , Hormona Folículo Estimulante/sangre , Inmunización Pasiva , Inhibinas/inmunología , Tamaño de la Camada/fisiología , Péptidos/inmunología , Animales , Femenino , Tamaño de la Camada/inmunología , Ovinos , Porcinos , Factores de Tiempo , Destete
5.
Biochemistry ; 16(2): 216-21, 1977 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-65177

RESUMEN

The C-terminal half of the bovine myelin basic protein, peptide 89-169, was treated with BNPS-skatole [2-(2-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine], and the products were isolated by repeated gel filtration through Sephadex G-50. They consisted of uncleaved peptide 89-169 in which approximately 30% of the tyrosine had been monobrominated and the tryptophan converted to oxindolealanine, peptide 116-169 modified by partial bromination (30%) of the tyrosine, and two chromatographic forms of peptide 89-115. The major form contained the lactone of dioxindolealanine at the C terminus; the minor form contained the uncyclized oxidation product. Each form of peptide 89-115 was resolved into several components by electrophoresis in polyacrylamide gels (10%, w/w) containing 1 M acetic acid and 8 M urea. The presence of three of these components could be explained by partial deamidation of Asn-91 and Gln-102. Studies on the oxidation of tryptophan-containing model peptides by BNPS-skatole indicated that the reaction can also include partial bromination of the dioxindole and its lactone and partial cleavage at the amino peptide bond of the tryptophan.


Asunto(s)
Proteína Básica de Mielina , Péptidos , Ácidos Sulfénicos , Aminoácidos/análisis , Animales , Bromo , Bovinos , Fenómenos Químicos , Química , Electroforesis en Gel de Poliacrilamida , Proteína Básica de Mielina/análisis , Péptidos/análisis , Escatol/análogos & derivados , Espectrofotometría Ultravioleta , Triptófano/análogos & derivados
8.
J Biol Chem ; 250(19): 7931-8, 1975 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-51849

RESUMEN

Two guinea pig myelin basic protein preparations which differed markedly in their contents of high pH electrophoretic or chromatographic forms were studied in an attempt to elucidate the causes of their microheterogeneity. Both total preparations and components isolated therefrom were examined for their amino acid compositions, NH2-terminal and COOH-terminal residues, total phosphorus contents, amd contents of phosphamino acids. The results showed that the five components differed sequentially by a single charge and that the microgeterogeneity arose as a result of secondary modifications of a single secies (Component 1) Of basic protein. Two modifications were demonstrated; viz. phosphorylation of serine and threonine and loss of COOH-terminal arginine. These two modifications were insufficient to account completely for the observed microheterogeneity; an additional cause, deamidation, was postulated. From the relationship between the number of components present in the total basic protein, the phosphorus and phosphoamino acid contents of the components, and the changes in relative electrophoretic mobility of the components which accompanied their phosphorylation and dephosphorylation we conclude that in the native basic protein no more than two sites in any polypeptide chain are phosphorylated.


Asunto(s)
Arginina , Proteína Básica de Mielina , Fosfatasa Alcalina , Secuencia de Aminoácidos , Aminoácidos/análisis , Animales , Arginina/análisis , Carboxipeptidasas , Cobayas , Compuestos Organofosforados/análisis , Proteínas Quinasas
10.
Biochemistry ; 14(5): 1067-73, 1975 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-47756

RESUMEN

Bovine and guinea pig myelin basic proteins were cleaved with pepsin at pH 3.0 or pH 6.0 (enzyme/substrate, 1:500, w/w), and the peptides were isolated and identified. At pH 3.0 cleavage of the bovine protein occurred principally at three sites: Phe-Phe (88-89), Phe-Phe (42-43), and Leu-Asp (36-37). Minor cleavages occurred at Leu-Ser (110-111), Phe-Ser (113-114), and Ile-Phe (152-153). A study of the time course of the hydrolysis showed that the reaction was biphasic; nearly all of the protein was cleaved at Phe-Phe (88-89) before significant cleavages at other sites occurred. At pH 6.0 cleavage of the bovine protein occurred almost exclusively at a single site, the Phe-Phe bond at position 88-89, resulting in bisection of the protein. Treatment of the guinea pig protein with pepsin under the same conditions resulted in the production of peptides which were identical with those of the bovine protein in chromatographic and electrophoretic properties and in N-terminal and C-terminal residues but which differed slightly in amino acid composition.


Asunto(s)
Proteína Básica de Mielina , Secuencia de Aminoácidos , Aminoácidos/análisis , Animales , Química Encefálica , Bovinos , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Cobayas , Concentración de Iones de Hidrógeno , Pepsina A , Fragmentos de Péptidos/análisis , Especificidad de la Especie
12.
Science ; 184(4132): 73-5, 1974 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-4131282

RESUMEN

Immnunization of guinea pigs with homologous myelin basic protein induces antibodies that differ in their ability to bind specific peptide fragments of the protein. Antiserums with differing specificities made it possible to demonstrate at least three mutually exclusive antigenic sites in the protein molecule. One of these sites is located between residues 44 and 89, another between 90 and 116, and the third between 117 and 170.


Asunto(s)
Epítopos , Proteína Básica de Mielina/análisis , Animales , Formación de Anticuerpos , Especificidad de Anticuerpos , Sitios de Unión de Anticuerpos , Encefalomielitis Autoinmune Experimental/prevención & control , Cobayas , Inmunización , Radioisótopos de Yodo , Fragmentos de Péptidos/análisis , Conformación Proteica , Radioinmunoensayo
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