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1.
J Dev Orig Health Dis ; 5(3): 206-13, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24901660

RESUMEN

Adverse uterine environments caused by maternal stress (such as bacterial endotoxin) can alter programming of the fetal hypothalamic-pituitary-adrenal axis (HPAA) rendering offspring susceptible to various adulthood diseases. Thus, protection against this type of stress may be critical for ensuring offspring health. The present study was designed to determine if maternal supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) during pregnancy helps to protect against stress-induced fetal programming. Briefly, 53 ewes were fed a diet supplemented with fishmeal (FM) or soybean meal (SM) from day 100 of gestation (gd100) through lactation. On gd135, half the ewes from each dietary group were challenged with either 1.2 µg/kg Escherichia coli lipopolysaccharide (LPS) endotoxin, or saline as the control. The offspring's cortisol response to weaning stress was assessed 50 days postpartum by measuring serum cortisol concentrations 0, 6 and 24 h post weaning. Twenty-four hours post-weaning, lambs were subjected to an adrenocorticotropic hormone (ACTH) challenge (0.5 µg/kg) and serum cortisol concentrations were measured 0, 0.25, 0.5, 1 and 2 h post injection. At 5.5 months of age, offspring were also challenged with 400 ng/kg of LPS, and serum cortisol concentrations were measured 0, 2, 4 and 6 h post challenge. Interestingly, female offspring born to FM+LPS mothers had a greater cortisol response to weaning and endotoxin challenge compared with the other treatments, while female offspring born to SM+LPS mothers had a faster cortisol response to the ACTH stressor. Additionally, males born to FM+LPS mothers had a greater cortisol response to the ACTH challenge than the other treatments. Overall, FM supplementation during gestation combined with LPS challenge alters HPAA responsiveness of the offspring into adulthood.


Asunto(s)
Suplementos Dietéticos , Endotoxinas/toxicidad , Desarrollo Fetal/fisiología , Productos Pesqueros , Sistema Hipotálamo-Hipofisario/crecimiento & desarrollo , Sistema Hipófiso-Suprarrenal/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Femenino , Desarrollo Fetal/efectos de los fármacos , Hidrocortisona/sangre , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/metabolismo , Embarazo , Distribución Aleatoria , Oveja Doméstica
2.
Animal ; 7(1): 151-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23031339

RESUMEN

In recent years, livestock producers have been supplementing animal diets with fish meal (FM) to produce value-added products for health conscious consumers. As components of FM have unique neuroendocrine-immunomodulatory properties, we hypothesize that livestock producers may be influencing the overall health of their animals by supplementing diets with FM. In this study, 40 pregnant ewes were supplemented with rumen protected (RP) soybean meal (SBM: control diet) or RP FM, commencing gestation day 100 (gd100), in order to evaluate the impact of FM supplementation on the innate and acquired immune response and neuroendocrine response of sheep during pregnancy and lactation. On gd135, half the ewes from each diet (n = 10 FM, n = 10 SBM) were challenged iv with lipopolysaccharide (LPS) to simulate a systemic bacterial infection and the febrile, respiratory and neuroendocrine responses were monitored over time; the other half (n = 10 FM, n = 10 SBM) of the ewes received a saline injection as control. On lactation day 20 (ld20), all ewes (n = 20 FM, n = 20 SBM) were sensitized with hen egg white lysozyme (HEWL) and the serum haptoglobin (Hp) response was measured over time. The cutaneous hypersensitivity response (CHR) to HEWL challenge was measured on ld30 (n = 20 FM, n = 20 SBM), and blood samples were collected over time to measure the primary and secondary immunoglobulin G (IgG) response to HEWL. There was an attenuated trend in the LPS-induced febrile response by the FM treatment when compared with the SBM treatment (P = 0.06), as was also true for the respiratory response (P = 0.07), but significant differences in neuroendocrine function (serum cortisol and plasma ACTH) were not observed between treatments. Basal Hp levels were significantly lower in the FM supplemented ewes when compared with the SBM supplemented ewes (P < 0.01), and the Hp response to HEWL sensitization differed significantly over time between treatments (P < 0.01). The CHR to HEWL was also significantly attenuated in the FM treatment compared with the SBM (P < 0.01); however, treatment differences in the primary and secondary IgG responses to HEWL were not observed. These results indicate that FM supplementation differentially affects the innate and acquired immune responses in pregnant and lactating sheep compared with a typical SBM diet of commercial flocks. The long-term implications of this immunomodulation warrant further investigation.


Asunto(s)
Suplementos Dietéticos , Productos Pesqueros , Glycine max , Lactancia/inmunología , Embarazo/inmunología , Oveja Doméstica/inmunología , Inmunidad Adaptativa , Animales , Dieta , Escherichia coli/inmunología , Femenino , Inmunidad Innata , Lipopolisacáridos/inmunología , Sistemas Neurosecretores/inmunología , Oveja Doméstica/metabolismo
3.
J Dairy Sci ; 93(10): 4860-71, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20855021

RESUMEN

Interleukin-12 (IL-12) and interleukin-23 (IL-23) are proinflammatory cytokines produced by macrophages and dendritic cells in response to infection with intracellular pathogens. The IL-12 receptor (IL-12R) is a heterodimer composed of 2 subunits, ß1 and ß2. The IL-23 receptor (IL-23R) is a heterodimer composed of the IL-12Rß1 subunit and a unique IL-23R subunit. Given the importance of IL-12 and IL-23 for modulating inflammation and the host immune response, the IL-12 and IL-23 receptor genes may be suitable candidate genes for studying disease resistance in dairy cattle. We hypothesize that single nucleotide polymorphisms (SNP) exist within these genes and that they contribute to variation in health and production traits in dairy cattle. To investigate this, a selective DNA pool was constructed using bull semen based on the estimated breeding values for somatic cell score (SCS), an indicator trait used to achieve genetic improvement for resistance to mastitis. Gene segments were amplified from this pool by PCR and the amplicons were sequenced to reveal SNP. A total of 10 SNP, including 2 in IL-12Rß1, 5 in IL-12Rß2, and 3 in IL-23R were identified. The SNP (n=5) were found in the 5' untranslated region (UTR) putative promoter regions of the genes, and SNP IL-23R c.1714A>C was a nonsynonymous SNP. Canadian Holstein bulls (n=492) were genotyped using Sequenom MassARRAY (Sequenom Inc., San Diego, CA). No association was found with SCS based on bull deregressed estimated breeding values for SCS; however, associations of SNP in the IL-12Rß2 gene (c.-511A>G, c.87A>G, c.2957A>C) were found with milk and protein yield. Further investigation will be required to elucidate the biological and practical relevance of these SNP.


Asunto(s)
Bovinos/genética , Interleucina-23 , Polimorfismo de Nucleótido Simple , Receptores de Interleucina-12/genética , Receptores de Interleucina/genética , Animales , Bovinos/fisiología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Lactancia/fisiología , Masculino , Mastitis Bovina/genética , Leche/química , Semen/química
4.
Food Chem Toxicol ; 48(10): 3000-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20678533

RESUMEN

An experiment was conducted to investigate the effects of dietary Fusarium mycotoxins on gut immunity, cell proliferation, and histology of avian lymphoid organs. The efficacy of a polymeric glucomannan mycotoxin adsorbent (GMA) was also determined. Seventy-two one-day-old male turkey poults were fed corn, wheat, and soybean meal-based diets for 21 days. Diets included control grains, contaminated grains and contaminated grains +0.2% GMA. The major contaminant was deoxynivalenol (3.9 µg/g) with lesser amounts of zearalenone (0.67-0.75 µg/g), 15-acetyl-deoxynivalenol (0.34 µg/g) and HT-2 toxin (0.078-0.085 µg/g). T- and B-lymphocyte populations and crypt cellular proliferation in duodenum, jejunum, ileum and cecal tonsil were measured immunohistochemically on day 14 and 21. Histological changes were recorded after 14 and 21 days of feeding. Feeding contaminated grains significantly increased the percentage of B-lymphocytes in ileum on day 14, and reduced (P<0.05) the percentages of CD8(+)-lymphocytes in cecal tonsil on day 21. GMA supplementation prevented these effects. The feeding of contaminated diets also caused a reduction (P<0.05) in ileal crypt proliferating cells and a significant increase in spleen secondary follicle on day 21. It was concluded that the feeding of grains naturally contaminated with Fusarium mycotoxins results in adverse effects on gut immunity and mucosal cell proliferation.


Asunto(s)
Fusarium/química , Intestinos/citología , Subgrupos Linfocitarios/efectos de los fármacos , Tejido Linfoide/patología , Micotoxinas/toxicidad , Pavos/fisiología , Alimentación Animal/efectos adversos , Alimentación Animal/análisis , Animales , Bolsa de Fabricio/patología , Proliferación Celular/efectos de los fármacos , Dieta , Procesamiento de Imagen Asistido por Computador , Inmunidad Mucosa/efectos de los fármacos , Inmunohistoquímica , Intestinos/efectos de los fármacos , Tejido Linfoide/efectos de los fármacos , Masculino , Mananos/química , Mananos/toxicidad , Micotoxicosis/inmunología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Aumento de Peso/efectos de los fármacos
5.
J Anim Sci ; 88(3): 998-1008, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19966173

RESUMEN

A study was conducted to assess the effects of feeding a blend of grains naturally contaminated with Fusarium mycotoxins to sows on the capacity for protein synthesis in skeletal muscle, the protein content per cellular unit, and the efficacy of a polymeric glucomannan adsorbent (GMA) to prevent these effects in late gestation and in lactation. Thirty-two Yorkshire sows were assigned to 4 treatment groups (8 per treatment) from 91 +/- 3 d of gestation up to weaning on d 21 after farrowing. Diets included 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% GMA. A fourth treatment of feeding sows the control diet at a restricted feed allowance was also included. The variables measured include ADFI, average daily BW change, serum total protein, urea, and ammonia, and skeletal muscle DNA, RNA, and protein. To assess the capacity for protein synthesis, ratios of RNA:DNA, and RNA:protein were compared among dietary treatments. To assess the degree of muscle protein mobilization in gestation and lactation, ratios of protein:DNA were compared among dietary treatments. Muscle samples were obtained from the triceps brachii. Blood and muscle samples were obtained 3 times: the first was obtained 1 d before the sows began to receive the experimental diets (90 +/- 3 d of gestation), a second sample was obtained 14 d later (104 +/- 3 d of gestation), and the third sample was obtained 10 d after farrowing. Serum ammonia concentrations were similar in sows fed the contaminated feed and sows fed the restricted feed compared with controls, but serum ammonia concentrations were greater in sows fed contaminated feed (P = 0.02) and restricted-fed sows (P = 0.008) compared with sows fed the contaminated grains plus GMA on 104 +/- 3 d of gestation. There were no reductions in the capacity for protein synthesis caused by mycotoxins or restricted feeding compared with controls. A reduction in ADFI (P = 0.003) was observed in sows fed the 2 contaminated diets in lactation. Muscle protein mobilization was not affected by diet, but a reduction (P = 0.04) in the content of protein per cellular unit was observed in lactation compared with gestation. Reduction in protein:DNA could be caused by the catabolic state in lactation, which was augmented by a low ADFI. The rate of muscle mobilization could be the result of the indirect effect of the reduction in ADFI in lactation rather than a direct effect of Fusarium mycotoxins in the capacity for protein synthesis.


Asunto(s)
Fusarium , Lactancia/efectos de los fármacos , Micotoxinas/efectos adversos , Proteínas/metabolismo , Animales , Proteínas Sanguíneas/análisis , Dieta/veterinaria , Femenino , Microbiología de Alimentos , Edad Gestacional , Músculo Esquelético/efectos de los fármacos , Embarazo , Biosíntesis de Proteínas/efectos de los fármacos , Porcinos/fisiología
6.
J Dairy Sci ; 92(4): 1585-93, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19307640

RESUMEN

A previous study in dairy cows showed some effect of feed contaminated with Fusarium mycotoxins on metabolism and immunity. A subsequent experiment investigated the effect of feedborne Fusarium mycotoxins on some immune functions in more detail. A total mixed ration (TMR) containing a blend of feedstuffs naturally contaminated with Fusarium mycotoxins was fed for 63 d to 12 mid-lactation Holstein cows with an average milk production of 36 kg/d in a completely randomized design with repeated measures including 1) control TMR and 2) contaminated TMR. Wheat, corn, hay, and corn silage were the contaminated feedstuffs. Deoxynivalenol was the major contaminant and was found in TMR at 3.5 mg/kg of dry matter. The parameters measured were 1) performance: body weight, body condition score, dry matter intake, milk production, composition and somatic cell count; 2) health: blood serum chemistry, hematology, coagulation profile, and rumen fluid ammonia levels; 3) immune function: total serum immunoglobulins (IgA, IgG, IgM), specific antibody response to ovalbumin, and neutrophil phagocytosis. Dry matter intake, body weight, milk production, and milk composition were not affected by diet. Neutrophil phagocytosis was depressed throughout the experiment in cows fed the contaminated diet. Serum sodium concentrations and osmolality were significantly elevated throughout the experiment in cows fed the contaminated diet. Primary antibody response to ovalbumin immunization was higher in cows fed the contaminated diet compared with controls. It was concluded that feed naturally contaminated with Fusarium mycotoxins can affect metabolic parameters and immune function of dairy cows.


Asunto(s)
Dieta/veterinaria , Microbiología de Alimentos , Fusarium , Sistema Inmunológico/efectos de los fármacos , Micotoxinas/toxicidad , Amoníaco/análisis , Alimentación Animal/análisis , Animales , Constitución Corporal/efectos de los fármacos , Bovinos/inmunología , Bovinos/metabolismo , Industria Lechera , Femenino , Inmunoglobulinas/inmunología , Lactancia/efectos de los fármacos , Micotoxinas/análisis , Neutrófilos/efectos de los fármacos , Ovalbúmina/inmunología , Fagocitosis/efectos de los fármacos , Distribución Aleatoria , Rumen/química , Rumen/efectos de los fármacos , Sodio/sangre
7.
Poult Sci ; 87(3): 421-32, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18281567

RESUMEN

An experiment was conducted to investigate the effects of feeding blends of grains naturally contaminated with Fusarium mycotoxins on performance, hematology, metabolism, and immunological parameters of turkeys. The efficacy of polymeric glucomannan mycotoxin adsorbent (GMA) in preventing these adverse effects was also evaluated. Three hundred 1-d-old male turkey poults were fed wheat-, corn-, and soybean meal-based starter (0 to 3 wk), grower (4 to 6 wk), developer (7 to 9 wk), and finisher (10 to 12 wk) diets formulated with uncontaminated grains, contaminated grains, and contaminated grains + 0.2% GMA. Feeding contaminated grains significantly decreased BW gains during the grower and developer phases, and GMA supplementation prevented these effects. There was no effect of diet, however, on feed intake or feed efficiency. The feeding of contaminated grains reduced total lymphocyte counts at wk 3 (P < 0.05). Dietary supplementation with GMA increased plasma total protein concentrations compared with controls and birds fed the contaminated diet. Plasma uric acid concentrations in birds fed contaminated grains were increased at the end of the experiment compared with controls, and the feeding of GMA prevented this effect. Feeding contaminated grains significantly increased the percentage of CD4(+) lymphocyte populations during wk 6; however, there was no change in the percentage of CD8(+) and B-lymphocyte populations. Contact hypersensitivity to dinitrochlorobenzene, which is a CD8(+) T cell-mediated delayed-type hypersensitivity response, was significantly decreased after 24 and 72 h by feedborne mycotoxins compared with controls. Supplementation of the contaminated diet with GMA prevented the decrease in response after 24 h. Secondary antibody (IgG titer) response against SRBC antigens (CD4(+) T cell-dependent) was significantly decreased after feeding contaminated grains compared with controls. It was concluded that turkey performance and some blood and immunological parameters were adversely affected by feedborne Fusarium mycotoxins, and GMA prevented many of these effects.


Asunto(s)
Contaminación de Alimentos , Mananos/farmacología , Micotoxicosis/veterinaria , Micotoxinas/toxicidad , Enfermedades de las Aves de Corral/inducido químicamente , Pavos , Alimentación Animal , Animales , Anticuerpos/sangre , Recuento de Linfocito CD4/veterinaria , Relación CD4-CD8 , Catárticos/farmacología , Grano Comestible/química , Grano Comestible/microbiología , Fusarium/metabolismo , Recuento de Linfocitos/veterinaria , Masculino , Micotoxicosis/sangre , Micotoxicosis/inmunología , Micotoxinas/antagonistas & inhibidores , Micotoxinas/biosíntesis , Tamaño de los Órganos , Enfermedades de las Aves de Corral/sangre , Enfermedades de las Aves de Corral/inmunología , Distribución Aleatoria , Pavos/crecimiento & desarrollo , Pavos/inmunología , Pavos/metabolismo , Aumento de Peso/efectos de los fármacos
8.
J Dairy Sci ; 90(8): 3867-73, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17638997

RESUMEN

Little is known about the effects of feedborne Fusarium mycotoxins on the performance, metabolism, and immunity of dairy cattle. A total mixed ration (TMR) containing a blend of feedstuffs naturally contaminated with Fusarium mycotoxins was fed for 56 d to 18 midlactation Holstein cows (average milk production, 33 kg/d) in a completely randomized design with repeated measures that included 3 treatments: 1) a control diet, 2) a contaminated diet, and 3) a contaminated diet + 0.2% polymeric glucomannan mycotoxin adsorbent (GMA). Wheat, corn, and hay were the contaminated feedstuffs used in the study. Deoxynivalenol was the major contaminant and was found in the TMR at levels of up to 3.6 microg/g of dry matter. Body weight, body condition score, dry matter intake, net energy balance, milk production, milk composition, somatic cell count, blood serum chemistry, hematology, serum Ig concentrations, and coagulation profile were measured. Dry matter intake and body weight, as well as milk production, milk composition, and SCC, were not affected by diet. Total serum protein and globulin levels increased significantly in cows fed the contaminated TMR compared with cows fed the control diet at 42 d, whereas the albumin:globulin ratio decreased. Serum urea concentrations were significantly elevated throughout the experiment in cows fed the contaminated diet compared with those fed the control diet. Serum IgA concentrations decreased significantly in cows fed the contaminated TMR at 36 d of feeding. Feeding GMA prevented these effects. Serum sodium concentration and osmolality levels were increased throughout the experiment in all cows fed the contaminated diets. We concluded that feed naturally contaminated with Fusarium mycotoxins can affect the metabolic parameters and immunity of dairy cows and that GMA can prevent some of these effects.


Asunto(s)
Peso Corporal/efectos de los fármacos , Bovinos/inmunología , Bovinos/metabolismo , Contaminación de Alimentos , Micotoxinas/farmacología , Alimentación Animal/análisis , Alimentación Animal/microbiología , Animales , Proteínas Sanguíneas/análisis , Constitución Corporal/efectos de los fármacos , Catárticos/administración & dosificación , Catárticos/farmacología , Bovinos/crecimiento & desarrollo , Industria Lechera , Ingestión de Alimentos/efectos de los fármacos , Femenino , Fusarium/química , Inmunoglobulina A/sangre , Lactancia/efectos de los fármacos , Lactancia/fisiología , Mananos/administración & dosificación , Mananos/farmacología , Leche/química , Leche/citología , Micotoxinas/administración & dosificación , Micotoxinas/inmunología , Distribución Aleatoria , Sodio/sangre , Urea/sangre
9.
Poult Sci ; 85(9): 1541-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16977839

RESUMEN

A study was conducted to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on performance and metabolism of broiler breeders. Forty-two 26-wk-old broiler breeder hens and nine 26-wk-old roosters were fed the following diets: (1) control, (2) contaminated grains, and (3) contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent (GMA) for 12 wk. The major contaminant was deoxynivalenol (12.6 mg/kg of feed), with lesser amounts of zearalenone and 15-acetyl-deoxynivalenol. Feed consumption and BW were not affected by diet. The feeding of contaminated grains did not significantly affect egg production. Decreased eggshell thickness was seen, however, at the end of wk 4, and dietary supplementation with GMA prevented this effect. There was no effect of diet on other egg parameters measured. There was a significant increase in early (1 to 7 d) embryonic mortality in eggs from birds fed contaminated grains at wk 4, but mid- (8 to 14 d) and late- (15 to 21 d) embryonic mortalities were not affected by diet. There were no differences in newly hatched chick weights or viability. The ratio of chick weight to egg weight was not affected by the feeding of contaminated grains. Weight gains of chicks fed a standard broiler starter diet at 7, 14, and 21 d of age were not significantly affected by previous dietary treatments for the dam. It was found that rooster semen volume and sperm concentration, viability, and motility were not affected by the feeding of contaminated diets. There was no effect of diet on the relative weights of liver, spleen, kidney, and testes. The feeding of contaminated grains decreased antibody titers against infectious bronchitis virus at the end of wk 12, and this was prevented by dietary supplementation with GMA. There was no effect of the diet on serum antibody titers against Newcastle disease virus. It was concluded that the feeding of blends of grains contaminated with Fusarium mycotoxins could affect performance and immunity in broiler breeder hens.


Asunto(s)
Alimentación Animal , Pollos/metabolismo , Pollos/fisiología , Fusarium , Micotoxinas/administración & dosificación , Micotoxinas/toxicidad , Reproducción/efectos de los fármacos , Animales , Pollos/inmunología , Femenino , Microbiología de Alimentos , Micotoxicosis/veterinaria , Micotoxinas/metabolismo , Enfermedades de las Aves de Corral/inducido químicamente
10.
J Anim Sci ; 84(8): 2083-8, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16864868

RESUMEN

Major changes in maternal physiology during pregnancy and lactation can have a large impact on the immune and neuroendocrine systems. One of the most significant changes, observed in rats and mice, is hyporesponsiveness of the hypothalamic pituitary adrenal axis (HPAA) in response to inflammation, restraint, and other psychological stressors during late pregnancy and lactation. This attenuation, however, has not been well characterized in ruminant animals and may be relevant to their susceptibility to inflammatory diseases during these periods. Thus, the intent of this study was to characterize responsiveness of the ovine HPAA to inflammatory challenge during pregnancy and lactation. Ewes from early (33 d), middle (55 d), and late (138 d) pregnancy, as well as early lactation (10 d), were challenged i.v. with a bolus dose of 400 ng of Escherichia coli lipopolysaccharide (LPS)/kg of BW or saline. A corresponding group of nonpregnant ewes was also challenged with LPS to serve as positive control animals for each pregnancy and lactation study. Responsiveness of the HPAA was assessed by measuring the 4-h change in serum cortisol concentration after LPS challenge. The cortisol increase after LPS challenge was elevated (P < 0.01) in pregnant ewes during late pregnancy over that of nonpregnant animals. In contrast, the characteristic temperature response associated with systemic LPS challenge was decreased (P < 0.01) during early pregnancy and lactation compared with nonpregnant or nonlactating animals. Serum IL-6 concentrations were measured to assess whether changes in HPAA responsiveness during pregnancy or lactation were attributed to changes in proinflammatory signaling to the HPAA. Interestingly, enhanced cortisol responsiveness during late pregnancy was correlated with increased (P < 0.01) serum IL-6 concentrations, indicating that IL-6 may contribute to enhanced HPAA responsiveness during this period. Serum IL-6 concentrations during early and midpregnancy did not increase in response to LPS challenge, indicating that HPAA activation during periods of pregnancy may be independent of IL-6 production.


Asunto(s)
Temperatura Corporal , Escherichia coli/inmunología , Hidrocortisona/sangre , Interleucina-6/sangre , Lactancia/fisiología , Lipopolisacáridos/farmacología , Ovinos/fisiología , Animales , Femenino , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/fisiología , Lipopolisacáridos/inmunología , Lipopolisacáridos/metabolismo , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/fisiología , Embarazo
11.
Poult Sci ; 84(8): 1179-85, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16156200

RESUMEN

Experiments were conducted to determine the effects of feeding grains naturally contaminated with Fusarium mycotoxins on performance, metabolism, hematology, and immune competence of ducklings. Four hundred sixty-four 1-d-old White Pekin male ducklings were fed starter (0 to 2 wk), grower (3 to 4 wk), and finisher (5 to 6 wk) diets formulated with uncontaminated grains, a low level of contaminated grains, a high level of contaminated grains, or the higher level of contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent. Body weight gains, feed consumption, and feed efficiency were not affected by diet. However, consumption of contaminated grains decreased plasma calcium concentrations after 2 wk and plasma uric acid concentrations at the 4-wk assessment point. Mean corpuscular hemoglobin concentrations and hematocrit decreased when ducks were fed contaminated grains for 4 or 6 wk, respectively. In contrast, total numbers of white blood cells and lymphocytes increased transiently in birds fed contaminated grains for 4 wk. The antibody response to sheep red blood cells (CD4+ T cell dependent) and the cell-mediated response to phytohemagglutinin-P (also CD4+ T cell dependent) were not affected by diet, but consumption of contaminated grains for 6 wk decreased the duration of peak cell-mediated response to dinitrochlorobenzene (CD8+ T cell dependent) assessed in a skin test. Feeding grains naturally contaminated with Fusarium mycotoxins, even at levels widely regarded as high, exerted only minor adverse effects on plasma chemistry and hematology of ducklings, and production parameters were unaffected in this avian species. Mycotoxin-contaminated feeds may, however, render these animals susceptible to infectious agents such as viruses against which the CD8+ T cell provides necessary defence. Glucomannan mycotoxin adsorbent was not effective in preventing alterations caused by Fusarium mycotoxins.


Asunto(s)
Alimentación Animal/análisis , Patos/fisiología , Fusarium , Micotoxicosis/veterinaria , Enfermedades de las Aves de Corral/inducido químicamente , Envejecimiento , Animales , Anticuerpos/sangre , Patos/sangre , Patos/inmunología , Grano Comestible , Contaminación de Alimentos , Linfocitos/inmunología , Masculino , Micotoxicosis/fisiopatología , Enfermedades de las Aves de Corral/fisiopatología , Distribución Aleatoria , Aumento de Peso/efectos de los fármacos
12.
Poult Sci ; 84(11): 1698-706, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16463966

RESUMEN

Feeding grains naturally-contaminated with Fusarium mycotoxins has been shown to alter the metabolism and performance of turkeys. The objectives of the current experiment were to examine the effects of feeding turkeys with grains naturally contaminated with Fusarium mycotoxins on their hematology and immunological indices (including functions), and the possible protective effect of feeding a polymeric glucomannan mycotoxin adsorbent (GMA). Two hundred twenty-five 1-d-old male turkey poults were fed corn, wheat, and soybean meal-based starter (0 to 3 wk), grower (4 to 6 wk), developer (7 to 9 wk), and finisher (10 to 12 wk) diets formulated with uncontaminated grains, contaminated grains, or contaminated grains with 0.2% GMA. The chronic consumption of Fusarium mycotoxins caused minor and transient changes in hematocrit (0.33 L/L) and hemoglobin (10(6) g/L) concentrations as well as in blood basophil (0.13 x 10(9)/L) and monocyte counts (3.42 x 10(9)/L) compared with controls. Supplementation of the contaminated diet with GMA prevented these effects on blood cell counts. Biliary IgA concentrations were significantly increased (4.45-fold) when birds were fed contaminated grains compared with controls, but serum IgA concentrations were not affected. Contact hypersensitivity to dinitrochlorobenzene, which is a CD8+ T-cell-mediated delayed-type hypersensitivity response, was decreased (48%) by feed-borne mycotoxins compared with the control. By contrast, the primary and secondary antibody response to sheep red blood cells, a CD4+ T-cell-mediated response, was not affected. It was concluded that chronic consumption of grains naturally contaminated with Fusarium mycotoxins exerts only minor adverse effects on the hematology and some immunological indices of turkeys. Consumption of grains naturally contaminated with Fusarium mycotoxins may, however, increase the susceptibility of turkeys to infectious agents against which CD8+ T cells play a major role in defense.


Asunto(s)
Contaminación de Alimentos , Micotoxicosis/veterinaria , Micotoxinas/toxicidad , Enfermedades de las Aves de Corral/sangre , Enfermedades de las Aves de Corral/inmunología , Pavos/sangre , Pavos/inmunología , Adsorción , Alimentación Animal , Animales , Fusarium/patogenicidad , Hipersensibilidad Tardía , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Mananos/farmacología , Micotoxicosis/sangre , Micotoxicosis/inmunología , Enfermedades de las Aves de Corral/inducido químicamente
13.
Poult Sci ; 84(12): 1841-50, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16479939

RESUMEN

Feeding grains naturally contaminated with Fusarium mycotoxins has been shown to alter metabolism and performance of laying hens. The objectives of the current experiment were to examine the effects of feeding grains naturally contaminated with Fusarium mycotoxins on hematology and immunological indices and functions of laying hens and the possible protective effect of feeding a polymeric glucomannan mycotoxin adsorbent (GMA). One hundred forty-four laying hens were fed for 12 wk with diets formulated with (1) uncontaminated grains, (2) contaminated grains, or (3) contaminated grains + 0.2% GMA. Fusarium mycotoxins such as deoxynivalenol (DON, 12 mg/kg), 15-acetyl-DON (0.5 mg/kg), and zearalenone (0.6 mg/kg) were identified in the contaminated diets arising from contaminated grains grown in Ontario, Canada. The concentrations of DON arising from naturally contaminated grains in this study were similar to purified mycotoxin fed to experimental mice. The chronic feeding of Fusarium mycotoxins induced small decreases in hematocrit values, total numbers of white blood cells, lymphocytes including both CD4+ and CD8+ T lymphocytes and B lymphocytes, and biliary IgA concentration. Supplementation of diets containing feedborne mycotoxins with GMA prevented the reduction in total number of B lymphocytes in the peripheral blood and the reduction in biliary IgA concentration. In addition, the delayed-type hypersensitivity response to dinitrochlorobenzene was increased by feed-borne mycotoxins, whereas IgG and IgM antibody titers to sheep red blood cells were not affected by diet. We concluded that chronic consumption of grains naturally contaminated with Fusarium mycotoxins at levels likely to be encountered in practice were not systemically immunosuppressive or hematotoxic; however, mucosal immunocompetence needs to be explored further.


Asunto(s)
Alimentación Animal , Pollos/sangre , Pollos/inmunología , Fusarium/química , Micotoxinas/administración & dosificación , Micotoxinas/toxicidad , Animales , Bilis/inmunología , Femenino , Contaminación de Alimentos/análisis , Hematócrito , Hemoglobinas , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Mananos/uso terapéutico , Micotoxinas/química , Micotoxinas/metabolismo , Oviposición , Proteínas Tirosina Quinasas , Proteínas Proto-Oncogénicas pp60(c-src) , Triticum , Zea mays
14.
Poult Sci ; 83(4): 533-43, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15109051

RESUMEN

An experiment was conducted to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on growth and immunological parameters of broiler chickens. Three hundred sixty, 1-d-old male broiler chicks were fed 1 of 4 diets containing grains naturally contaminated with Fusarium mycotoxins for 56 d. The diets included (1) control; (2) low level of contaminated grains (5.9 mg/kg deoxynivalenol (DON), 19.1 mg/kg fusaric acid (FA), 0.4 mg/kg zearalenone, and 0.3 mg/kg 15-acetyldeoxynivalenol; (3) high level of contaminated grains (9.5 mg/kg DON, 21.4 mg/kg FA, 0.7 mg/kg zearalenone, and 0.5 mg/kg 15-acetyldeoxynivalenol); and (4) high level of contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent (GM polymer). Body weight gains and feed consumption of chickens fed contaminated grains decreased linearly with the inclusion of contaminated grains during the grower phase (d 21 to 42). Efficiency of feed utilization, however, was not affected by diet. Production parameters were not significantly affected by the supplementation of GM polymer to the contaminated grains. Peripheral blood monocytes decreased linearly in birds fed contaminated grains. The feeding of contaminated diets linearly reduced the B-cell count at the end of the experiment, whereas the T-cell count on d 28 responded quadratically to the contaminated diets. The feeding of contaminated diets did not significantly alter serum or bile immunoglobulin concentrations, contact hypersensitivity to dinitrochlorobenzene, or antibody response to SRBC. Supplementation with GM polymer in the contaminated diet nonspecifically increased white blood cell count and lymphocyte count, while preventing mycotoxin-induced decreases in B-cell counts. It was concluded that broiler chickens are susceptible during extended feeding of grains naturally contaminated with Fusarium mycotoxins.


Asunto(s)
Alimentación Animal/microbiología , Pollos/inmunología , Ingestión de Energía/efectos de los fármacos , Contaminación de Alimentos/análisis , Micotoxinas/toxicidad , Aumento de Peso/efectos de los fármacos , Animales , Dermatitis por Contacto/veterinaria , Fusarium , Inmunofenotipificación , Linfocitos/inmunología , Masculino , Carne , Tamaño de los Órganos/efectos de los fármacos , Enfermedades de las Aves de Corral/inmunología , Tricotecenos/toxicidad , Zearalenona/toxicidad
15.
J Anim Sci ; 81(11): 2792-803, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14601883

RESUMEN

An experiment was conducted to investigate the effects of feeding a blend of grains naturally contaminated with Fusarium mycotoxins on growth and immunological parameters of starter pigs. A polymeric glucomannan mycotoxin adsorbent (GM polymer, Alltech Inc., Nicholasville, KY) was also tested for its efficacy in preventing Fusarium mycotoxicoses. A total of 150 starter pigs (initial weight of 9.3 +/- 1.1 kg) were fed one of five treatment diets (six pens of five pigs per diet) for 21 d. Diets included control, low level of contaminated grains, high level of contaminated grains, high level of contaminated grains + 0.20% GM polymer, and pair-fed control for comparison with pigs receiving the high level of contaminated grains. Feed intake and cumulative weight gain of pigs decreased linearly with the inclusion of contaminated grains in the diet throughout the experiment (P < 0.0001). Weight gains recovered, however, during wk 3 (P > 0.05). There was no difference between the pair-fed group and the pigs fed the diet containing the high level of contaminated grains in terms of weight gain or feed efficiency (P > 0.05). Feeding contaminated grains linearly increased the serum albumin:globulin ratio (P = 0.01), whereas serum urea concentrations and gamma-glutamyltransferase activities responded in a quadratic fashion (P = 0.02). When compared with the pair-fed pigs, serum concentrations of total protein (P = 0.01) and globulin (P = 0.02) were decreased in pigs fed the diet containing the high level of contaminated grains. The feeding of contaminated diets did not significantly alter organ weights expressed as a percentage of BW, serum immunoglobulin concentrations, percentages of peripheral blood lymphocyte subsets, contact hypersensitivity to dinitrochlorobenzene, or primary antibody response to sheep red blood cells (P > 0.05). It was concluded that most of the adverse effects of feeding Fusarium mycotoxin-contaminated grains to starter pigs were caused by reduced feed intake. Although supplementation of GM polymer to the contaminated diet prevented some toxin-induced changes in metabolism, it did not prevent the mycotoxin-induced growth depression under the current experimental conditions.


Asunto(s)
Grano Comestible/química , Contaminación de Alimentos , Mananos/farmacología , Micotoxinas/administración & dosificación , Porcinos/crecimiento & desarrollo , Adsorción , Alimentación Animal , Animales , Análisis Químico de la Sangre , Ingestión de Alimentos/efectos de los fármacos , Femenino , Fusarium/metabolismo , Inmunoglobulinas/sangre , Masculino , Mananos/metabolismo , Micotoxinas/efectos adversos , Micotoxinas/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Porcinos/sangre , Porcinos/inmunología , Aumento de Peso/efectos de los fármacos
16.
Poult Sci ; 81(7): 966-75, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12162357

RESUMEN

Three hundred sixty, 1-d-old male broiler chicks were fed diets containing grains naturally contaminated with Fusarium mycotoxins for 56 d. The four diets included control (0.14 mg/kg deoxynivalenol, 18 mg/ kg fusaric acid, < 0.1 mg/kg zearalenone), low level of contaminated grains (4.7 mg/kg deoxynivalenol, 20.6 mg/kg fusaric acid, 0.2 mg/kg zearalenone), and high level of contaminated grains without (8.2 mg/kg deoxynivalenol, 20.3 mg/kg fusaric acid, 0.56 mg/kg zearalenone) and with (9.7 mg/kg deoxynivalenol, 21.6 mg/kg fusaric acid, 0.8 mg/kg zearalenone) 0.2% esterified-glucomannan polymer derived from Saccharomyces cerevisiae1026 (E-GM). Body weight gain and feed consumption responded in a significant quadratic fashion to the inclusion of contaminated grains during the finisher period. Efficiency of feed utilization, however, was not affected by diets. The feeding of contaminated grains in the finisher period also caused significant linear increases in blood erythrocyte count and serum uric acid concentration and a significant linear decline in the serum lipase activity. Dietary inclusion of contaminated grains resulted in a significant quadratic effect on serum albumin and y-glutamyltransferase activity. Blood hemoglobin and biliary IgA concentrations, however, responded in significant linear and quadratic fashions. Supplementation of E-GM counteracted most of the blood parameter alterations caused by the Fusarium mycotoxin-contaminated grains and reduced breast muscle redness. It was concluded that broiler chickens may be susceptible to Fusarium mycotoxicoses when naturally contaminated grains are fed containing a combination of mycotoxins.


Asunto(s)
Alimentación Animal/análisis , Pollos/fisiología , Contaminación de Alimentos , Fusarium , Micotoxinas/administración & dosificación , Animales , Pollos/metabolismo , Color , Ingestión de Alimentos , Recuento de Eritrocitos , Índices de Eritrocitos , Ácido Fusárico/administración & dosificación , Hematócrito , Hemoglobinas/análisis , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Músculo Esquelético , Tricotecenos/administración & dosificación , Zearalenona/administración & dosificación , gamma-Glutamiltransferasa/sangre
17.
J Anim Sci ; 80(12): 3257-67, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12542167

RESUMEN

The co-occurrence of Fusarium mycotoxins in contaminated swine diets has been shown to result in synergistic toxicity beyond that observed for individual toxins. An experiment was conducted, therefore, to investigate the effects of feeding a blend of grains naturally contaminated with Fusarium mycotoxins on growth, brain regional neurochemistry, serum immunoglobulin (Ig) concentrations, serum chemistry, hematology, and organ weights of starter pigs. Three levels of glucomannan polymer (GM polymer, extract of yeast cell wall, Alltech Inc.) were also tested for its efficacy to overcome Fusarium mycotoxicoses. A total of 175 starter pigs (initial weight of 10 +/- 1.1 kg) were fed five diets (seven pens of five pigs per diet) for 21 d. Diets included (1) control, (2) blend of contaminated grains, (3) contaminated grains + 0.05% GM polymer (4) contaminated grains + 0.10% GM polymer and (5) contaminated grains + 0.20% GM polymer. Diets containing contaminated grains averaged 5.5 ppm deoxynivalenol, 0.5 ppm 15-acetyldeoxynivalenol, 26.8 ppm fuuric acid, and 0.4 ppm zearalenone. Feed intake and weight gain of all pigs fed contaminated grains was significantly reduced compared to controls throughout the experiment. The weights of liver and kidney, expressed as a percentage of body weight, were lower in pigs fed the contaminated diet than in those fed the control diet. The feeding of contaminated grains significantly reduced concentrations of dopamine in the hypothalamus and pons and concentrations of dihydroxyphenylacetic acid and norepinephrine in the pons. The ratios of 5-hydroxyindoleacetic acid to serotonin, however, were elevated in the hypothalamus and pons. The feeding of contaminated grains increased serum IgM and IgA concentrations, while serum IgG concentrations were not altered. The supplementation of GM polymer prevented some of the mycotoxin-induced alterations in brain neurotransmitter and serum Ig concentrations. In summary, the feeding of grains naturally contaminated with Fusarium mycotoxins reduced growth, altered brain neurochemistry, increased serum Ig concentrations, and decreased organ weights in starter pigs. Some of the Fusarium mycotoxin-induced changes in neurochemistry and serum Ig concentrations can be prevented by the feeding of yeast cell wall polymer at appropriate concentrations, although this was not reflected in increased growth rate under these experimental conditions.


Asunto(s)
Química Encefálica/efectos de los fármacos , Grano Comestible/química , Contaminación de Alimentos , Micotoxinas/administración & dosificación , Porcinos/crecimiento & desarrollo , Adsorción , Alimentación Animal/análisis , Animales , Análisis Químico de la Sangre/veterinaria , Ingestión de Alimentos/efectos de los fármacos , Grano Comestible/microbiología , Femenino , Fusarium/metabolismo , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Mananos/farmacología , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Porcinos/sangre , Porcinos/fisiología , Aumento de Peso/efectos de los fármacos
18.
J Biol Chem ; 276(41): 37929-33, 2001 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-11489889

RESUMEN

A novel microsomal beta-glucosidase was recently purified and characterized from human liver that catalyzes the hydrolysis of bile acid 3-O-glucosides as endogenous compounds. The primary structure of this bile acid beta-glucosidase was deduced by cDNA cloning on the basis of the amino acid sequences of peptides obtained from the purified enzyme by proteinase digestion. The isolated cDNA comprises 3639 base pairs containing 524 nucleotides of 5'-untranslated and 334 nucleotides of 3'-untranslated sequences including the poly(A) tail. The open reading frame predicts a 927-amino acid protein with a calculated M(r) of 104,648 containing one putative transmembrane domain. Data base searches revealed no homology with any known glycosyl hydrolase or other functionally identified protein. The cDNA sequence was found with significant identity in the human chromosome 9 clone RP11-112J3 of the human genome project. The recombinant enzyme was expressed in a tagged form in COS-7 cells where it displayed bile acid beta-glucosidase activity. Northern blot analysis of various human tissues revealed high levels of expression of the bile acid beta-glucosidase mRNA (3.6-kilobase message) in brain, heart, skeletal muscle, kidney, and placenta and lower levels of expression in the liver and other organs.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , beta-Glucosidasa/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células COS , Clonación Molecular , ADN Complementario , Etiquetas de Secuencia Expresada , Humanos , Datos de Secuencia Molecular , beta-Glucosidasa/metabolismo
19.
J Toxicol Environ Health A ; 63(5): 363-81, 2001 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-11471867

RESUMEN

An outdoor microcosm study was conducted in order to evaluate the kinetics of immunomodulation in rainbow trout (Oncorhynchus mykiss) exposed to liquid creosote. Fish were sampled on d 7, 14, 21, and 28 from microcosms dosed initially with 0, 3, and 10 microl/L of creosote. Pronephros leukocytes were monitored for phagocytic activity, oxidative burst, and surface immunoglobulin-positive (Slg+) B-cell counts. Oxidative burst was inhibited by creosote exposure; however, by sampling d 28, the burst response returned to near control levels. Phagocytic activity, on the other hand, was stimulated, peaking on sampling d 7, then returning to near control levels by d 28. Although control Slg+ B-cell counts were quite variable across sampling days, Slg+ B-cell counts were also elevated in creosote-exposed fish after seven days of exposure. Slg+ B-cell numbers decreased significantly to near control levels during the remainder of the study. The overall results from this study confirm that creosote has the potential to alter certain immune parameters, and emphasize the importance of monitoring changes in the immune system during exposure. Polycyclic aromatic hydrocarbons (PAHs), a major constituent of liquid creosote, are the suspected immune-altering agents.


Asunto(s)
Linfocitos B/efectos de los fármacos , Creosota/toxicidad , Inmunidad Celular/efectos de los fármacos , Oncorhynchus mykiss/fisiología , Fagocitosis/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Femenino , Inmunoglobulina M/inmunología , Recuento de Leucocitos , Estallido Respiratorio/efectos de los fármacos , Temperatura
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