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1.
Theriogenology ; 142: 338-347, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31711709

RESUMO

The objective of this study was to determine the effects of prepartum negative dietary cation-anion difference diet (DCAD) fed at two dietary Ca inclusion rates on postpartum uterine health and ovulation dynamics of multiparous Holstein cows (n = 76). Treatments began at 28 days before expected calving until parturition and were: CON: DCAD = +6 mEq/100g of DM with low dietary Ca (46.2 ± 15.2 g Ca/d; 0.4% DM; n = 26); ND: DCAD = -24 mEq/100g of DM with low dietary Ca (44.1 ±â€¯16.1 Ca/d; 0.4% DM; n = 24); NDCA: DCAD = -24 mEq/100g of DM with high dietary Ca (226.6 ±â€¯96.0 g Ca/d; 2.0% DM; n = 26). Vaginal discharge was evaluated through the fresh period via Metricheck (MC) for presence of purulent material. Polymorphonuclear (PMN) cell concentration in the uterus was evaluated at 15 and 30 days relative to calving (DRC). Endometrial tissue was harvested at 30 DRC for glandular morphology, presence of tight-junctions and adheren-junctions proteins, as well as assessment of superoxide dismutase (SOD) and glutathione peroxidase (GPX) activity. Blood plasma and serum samples were harvested in the prepartum and postpartum phase and were assessed for concentrations of lipopolysaccharide binding protein (LBP), serum amyloid A (SAA), and haptoglobin (HP). Ovarian dynamics were assessed through the fresh period until first timed artificial insemination (TAI). Cows fed CON had a lower MC score (P = 0.06) than the average of cows fed ND and cows fed NDCA. Cows fed ND had a higher MC score than cows fed NDCA. Cows fed NDCA had greater uterine gland epithelial height (P = 0.02) than cows fed ND. Cows fed NDCA also had a greater number of epithelial cells per gland (P = 0.05) than cows fed ND. Cows fed NDCA had greater intensity of occludin expression (P = 0.15) than cows fed ND. Cows fed NDCA had increased activity of SOD (P = 0.05) and decreased activity of GPX (P < 0.001) than cows fed ND. Cows fed ND had higher plasma HP concentrations than cows fed NDCA in the prepartum (P = 0.01) and post-partum (P = 0.03) periods. Cows fed ND and NDCA had lower (P = 0.01) postpartum plasma HP concentration than cows fed CON. In conclusion, cows fed NDCA had an improved uterine environment most likely due to alleviation of oxidative stress, an enhanced immune response to parturition and uterine discharge comparable to cows fed CON.


Assuntos
Ácidos/administração & dosagem , Cálcio da Dieta/administração & dosagem , Endometrite/prevenção & controle , Fertilidade/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Materna , Transtornos Puerperais/prevenção & controle , Útero/efeitos dos fármacos , Ácidos/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Cálcio da Dieta/farmacologia , Bovinos , Doenças dos Bovinos/prevenção & controle , Dieta/veterinária , Endometrite/veterinária , Feminino , Fertilidade/fisiologia , Lactação/efeitos dos fármacos , Lactação/fisiologia , Fenômenos Fisiológicos da Nutrição Materna/efeitos dos fármacos , Leite , Período Pós-Parto/efeitos dos fármacos , Gravidez , Transtornos Puerperais/veterinária , Útero/fisiologia
2.
Sci Rep ; 8(1): 11615, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072754

RESUMO

Nicotine and acetylcholine cause immunosuppresion by signaling to the α7 nicotinic acetylcholine receptor (α7 nAChR) on immune cells. Neonicotinoids are nAChR agonists and widly used insecticides. We aimed to define the immunosuppressive potential of dietary exposure to the neonicotinoid imidacloprid (IMI) on the generation of innate and adaptive immune responses to porcine reproductive and respiratory syndrome virus (PRRSV). Piglets were randomized into groups based on diet and infection. Behavioral signs of illness were recorded. Urine IMI levels were measured by high performance liquid chromatography-mass spectrometry. Flow cytometry was used to determine the expression pattern of the α7 nAChR on porcine leukocytes as well as the effects of infection and treatment on circulating leukocyte populations. Serum cytokines and PRRSV-specific antibody levels were determined by ELISA. Viral RNA in lung, spleen and plasma was determined by RT-qPCR. Pigs in the treatment group had elevated urine levels of IMI. Treatment with IMI reduced body weight, caused bouts of hypothermia, increased serum IL-10 and elevated levels of virus-specific antibodies. Viral RNA levels in the spleen showed a trend toward being increased in pigs fed IMI. Our data indicates that IMI injection may modulate virus specific immune function during PRRSV infection.


Assuntos
Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Animais , Citocinas/sangue , Citocinas/imunologia , Feminino , Masculino , Camundongos , Síndrome Respiratória e Reprodutiva Suína/sangue , Síndrome Respiratória e Reprodutiva Suína/patologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , RNA Viral/imunologia , RNA Viral/metabolismo , Distribuição Aleatória , Suínos , Receptor Nicotínico de Acetilcolina alfa7/imunologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
3.
Theriogenology ; 114: 116-125, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29609181

RESUMO

During the transition from prepartum to early lactation, dairy cows often experience negative energy balance (NEB) that may result in reproductive stress and decreased fertility. The objective of this study was to observe the effects of rumen-protected methionine (RPM) on plasma amino acid concentrations, uterine cytology, immunohistochemistry (IHC) of glutathione peroxidase 1 (GPX) and superoxide dismutase 1 (SOD), and to confirm neutrophil extracellular trap (NET) formation. Multiparous Holstein cows (n = 20) were randomly assigned to two treatments starting at 21 d before calving until 73 days in milk (DIM). Treatments were: CON (n = 9, no supplementation, TMR with a Lys:Met = 3.5:1) and MET (n = 11, TMR + Smartamine® M with a Lys:Met = 2.8:1). Uterine endometrial biopsies, uterine cytology, and blood samples from the coccygeal artery or vein were collected at 15, 30, and 73 DIM. Blood plasma samples were analyzed for amino acids and metabolites. Uterine biopsies were analyzed for NET formation, neutrophil numbers, as well as GPX and SOD by IHC. Additionally, uterine cytology was analyzed for polymorphonuclear neutrophil (PMN) to epithelial cell percentage. Cows in CON had lower methionine plasma concentrations (18.05 ±â€¯2.0 µM) than cows in MET (30.39 ±â€¯1.6 µM). Cows in CON had greater cystine plasma concentrations (3.62 ±â€¯0.3 µM) than cows in MET (2.8 ±â€¯0.3 µM). No treatment differences were observed for SOD or GPX in the endometrium. Cows in CON tended to have a high score for positively immunolabeled GPX cells at 15 DIM than cows in MET. No treatment differences were observed for the percentage of PMN in uterine cytology, number of neutrophils, or extent of NET formation in the endometrium. A treatment by time interaction was observed for PMN percentage and the number of neutrophils: cows in MET tended to have greater PMN percentages than cows in CON at 15 DIM which decreased for subsequent days and cows in MET had greater neutrophil numbers in the endometrium at 30 DIM than cows in CON. In conclusion, dietary supplementation of RPM altered plasma amino acid concentrations and increased neutrophil infiltration in the postpartum period, suggesting improved uterine immunity.


Assuntos
Bovinos , Armadilhas Extracelulares/fisiologia , Metionina/farmacologia , Neutrófilos/fisiologia , Útero/fisiologia , Animais , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação , Metionina/administração & dosagem , Rúmen , Útero/imunologia
4.
Brain Behav Immun ; 40: 110-20, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24632225

RESUMO

Previous research has shown that neonatal handling has prolonged protective effects associated with stress resilience and aging, yet little is known about its effect on stress-induced modulation of infectious disease. We have previously demonstrated that social disruption stress exacerbates the acute and chronic phases of the disease when applied prior to Theiler's virus infection (PRE-SDR) whereas it attenuates disease severity when applied concurrently with infection (CON-SDR). Here, we asked whether neonatal handling would protect adult mice from the detrimental effects of PRE-SDR and attenuate the protective effects of CON-SDR on Theiler's virus infection. As expected, handling alone decreased IL-6 and corticosterone levels, protected the non-stressed adult mice from motor impairment throughout infection and reduced antibodies to myelin components (PLP, MBP) during the autoimmune phase of disease. In contrast, neonatal handling X PRE/CON-SDR elevated IL-6 and reduced corticosterone as well as increased motor impairment during the acute phase of the infection. Neonatal handling X PRE/CON-SDR continued to exacerbate motor impairment during the chronic phase, whereas only neonatal handling X PRE-SDR increased in antibodies to PLP, MOG, MBP and TMEV. Together, these results imply that while handling reduced the severity of later Theiler's virus infection in non-stressed mice, brief handling may not be protective when paired with later social stress.


Assuntos
Infecções por Cardiovirus/imunologia , Manobra Psicológica , Comportamento Social , Estresse Psicológico/imunologia , Theilovirus/imunologia , Doença Aguda , Fatores Etários , Animais , Animais Recém-Nascidos , Doença Crônica , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Atividade Motora/imunologia , Proteínas da Mielina/imunologia
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