62 research outputs found
Effect of ochratoxin A on the intestinal mucosa and mucosa-associated lymphoid tissues in broiler chickens
The immunotoxic effect of ochratoxin A (OTA) on the intestinal mucosa-associated lymphoid tissue and its cytotoxic action on the intestinal epithelium were studied in broiler chickens experimentally treated with the toxin. From the 7th day of life, 80 male broiler chickens (Ross 308) were randomly divided into four groups of 20 birds each. The three experimental groups (E1-3) were treated with OTA for 28 days (E1: 50 μg/kg body weight [bw]/day; E2: 20 μg/kg bw/day; E3: 1 μg/kg bw/day) and the fourth group served as control. Histological examination of the intestinal mucosa and immunohistochemical staining for identification of CD4+, CD8+, TCR1 and TCR2 lymphocytes in the duodenum, jejunum and ileocaecal junction were performed, and CD4+/CD8+ and TCR1/TCR2 ratios were calculated. OTA toxicity resulted in decreased body weight gain, poorer feed conversion ratio, lower leukocyte and lymphocyte count, and altered intestinal mucosa architecture. After 14 days of exposure to OTA, immunohistochemistry showed a significant reduction of the lymphocyte population in the intestinal epithelium and the lamina propria. After 28 days of exposure, an increase in the CD4+ and CD8+ values in both the duodenum and jejunum of chickens in Groups E1 and E2 was observed, but the TCR1 and TCR2 lymphocyte counts showed a significant reduction. No significant changes were observed in Group E3. The results indicate that OTA induced a decrease in leukocyte and lymphocyte counts and was cytotoxic to the intestinal epithelium and the mucosa-associated lymphoid tissue, altering the intestinal barrier and increasing susceptibility to various associated diseases
Effects of ZooBioR2 product as feed supplement in laying hens on the morphofunctional state of intestinal mucosa
Spirulina platensis is a microalga with biological activity used to produce nutritional supplements rich in proteins, essential fatty acids, vitamins, and minerals. The current study aims to prove the impact of the product ZooBioR2 (obtained from Spirulina platensis) on health, and on the histology of duodenum, jejunum, ileum, and cecum in laying hens. The experiment was performed in duplicate on 5 groups of hens (14 birds/group), one control and four experimental, in which the feed was supplemented with ZooBioR2 in different doses (5.0; 10.0; 15.0; 20.0mg active substance/kg of fodder). Inclusion of the supplement in the diet have determined a significant decrease of height of intestinal villi, the depth of the crypts and the thickness of muscular layer of mucosa in the experimental groups receiving 15.0 and 20.0mg/kg. The decrease of crypts depth is an indicator of a higher rate of turn-over of epithelial tissue. The morphological changes of intestinal mucosa could be involved in a better digestibility of the fodder.Spirulina platensis é uma microalga com atividade biológica utilizada para produzir suplementos nutricionais ricos em proteínas, ácidos graxos essenciais, vitaminas e minerais. O estudo atual visa provar o impacto do produto ZooBioR2 (obtido da Spirulina platensis) na saúde e na histologia doduodeno, jejuno, íleo e ceco em galinhas poedeiras. O experimento foi realizado em duplicata em cinco grupos de galinhas (14 aves/grupo), um controle e quatro experimentais, nos quais a ração foi suplementada com ZooBioR2 em diferentes doses (5,0; 10,0; 15,0; 20,0mg de substância ativa/kg de forragem). A inclusão do suplemento na ração determinou uma diminuição significativa da altura das vilosidades intestinais, da profundidade dos crypts e da espessura da camada muscular da mucosa nos grupos experimentais que receberam15,0 e 20,0mg/kg. A diminuição da profundidade das criptas é um indicador de maior taxa de rotação do tecido epitelial. As alterações morfológicas da mucosa intestinal podem estar envolvidas em uma melhor digestibilidade da forragem
News and views of neuroprotection in complete traumatic spinal cord injuries
Spinal cord injury (SCI) due to trauma has major functional, medical, and financial effects on the injured person, as well as an important effect on the individual's psychosocial well-being. These patients have not any treatment for their or tetraplegia and any therapeutical attempt can bring hope and can improve their quality of life. Today methylprednisolone is a standard treatment option for an acute spinal cord injury but it is not a cure for a spinal cord injury. Surgery is often necessary for decompression, to realign and to stabilize the spine. The experimental treatments had yet not results. In case of acute complete traumatic SCI, steroid medication is insufficient and it is necessary to add new immediate procedures at the standard treatment performed today. Treatment should be started immediately and must stop cell death, control inflammation and promote nerve regeneration (action to primary and secondary damage)
Immunosuppressive Action of Deoxynivalenol of Thymus in Chickens
Abstract
Deoxynivalenol (DON, vomitoxin) is a type B-trichothecene, naturally occurring contaminants of animal feed, being implicated in several mycotoxicoses in farm livestock. This mycotoxin occurs predominantly in grains such as wheat, barley, oats, rye, and maize, and less often in rice, sorghum, and triticale. Deoxynivalenol is potent nefrotoxic, hepatotoxic and immunosuppressant. High doses of trichothecenes promote rapid onset of leukocyte apoptosis (programmed cell death), which is manifested as immunosuppression. The study aimed to prove the immunosuppressant action of deoxynivalenol in chickens experimentally treated each day, from the 7th day of life, using 5,4 mg/kg b.w in E group for 28 days (since 35 days of life). Histopathology studies of thymus were made on 7th, 14th, 21st and 28th days of experiment. In E group small lesions of thymus were observed even after 7th day of poisoning but intense lesions, hydropic degeneration, necrotic foci and moderate lymphoid depletion was observed after the 14th and 21st day of poisoning. After 28th day a marked proliferation of stromal cells in the reticulum network, in medulla zone, presence of mucous cells, small mucous cysts and haemorages were observed.</jats:p
Effect of Selenium Supplementation on Serum Amylase, Lactate Dehydrogenase and Alkaline Phosphatase Activities in Rats Exposed to Cadmium or Lead
Abstract
The purpose of the study was to assess the effect of selenium supplementation on serum amylase, lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) activities in rats, during subacute exposure to toxic doses of cadmium or lead through the drinking water. The experimental groups (n=6) were: Control, Se (Se+4: 0,2 mg/l), Cd (Cd+2: 150 mg/l), Pb (Pb+2: 300 mg/l), Cd+Se (Cd+2: 150 mg/l; Se+4: 0,2 mg/l) and Pb+Se (Pb+2: 300 mg/l; Se+4: 0,2 mg/l). The animals were sacrificed after 56 days. Amylase, LDH and ALP activities were determined from serum. Se and Pb treatments caused an increase in amylase and LDH activities, when compared to Control group while Cd caused an increase in amylase activity and a decrease in LDH and ALP activities. Cd+Se caused a decrease in amylase activity and an increase in LDH activity, when compared to Cd. Pb+Se caused a decrease in amylase activity in comparison to lead. Selenium supplementation alleviated cadmium or lead induced changes in serum amylase activity. Selenium, coadministered with cadmium, caused a marked increase in serum LDH activity, when compared to cadmium alone or Control group while practically it had no effect on lead induced changes in LDH activity. Cadmium and lead induced disturbances in serum ALP activity were not influenced by selenium supplementation.</jats:p
Presence of nerve growth factor (NGF) and tyrosine kinase A receptor (Trk A) in diseased cat kidneys
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