This study examined the mitogenic response of bovine peripheral T lymphocytes to leptin, a pleiotropic hormone regulating food intake and energy expenditure. Leptin alone slightly suppressed proliferation of T lymphocytes in the presence of concanavalin A (ConA). Leptin also inhibited proliferation of T lymphocytes induced by anti-CD3 antibody. ConA treatment activated some protein kinases, including p44/p42(MAPK) and Akt/PKB, while anti-CD3 antibody treatment increased mRNA expression of suppressor of cytokine signalling (SOCS) 3, interferon (IFN)gamma, interleukin (IL) 2 and IL4 in T lymphocytes. Leptin alone increased only SOCS3 mRNA expression. Simultaneous treatment with mitogens and leptin enhanced IFNgamma mRNA expression but decreased IL2 mRNA expression, without any synergistic effect on phosphorylation of protein kinases or mRNA expression of SOCS3 and IL4. These results suggest that leptin modulates bovine T lymphocyte functions. 相似文献
The New Zealand White (NZW) was superior significantly ( P < 0.05) to the Californian (Cal) breed in final body weight, final total body solids and preslaughter weight. In contrast, Cal showed greater plasma creatinine ( P < 0.001) than the NZW. The differences in the other traits were not significant. NZW also showed higher dressing percentage and Cal showed higher mortality percentage. The Temperature-humidity Index (THI) values indicated absence of heat stress in the first period (mild period) and exposure to moderate (very close to severe) heat stress in the second one (hot period). The heat stress conditions caused significant ( P < 0.001, 0.01 or 0.05) decreases in each of final body weight, daily body gain, daily feed intake, final total body solids, solids daily gain, plasma total protein, albumin, globulin, total lipids, glucose, thyroid hormone T3, sodium, potassium, calcium, magnesium and phosphorus and preslaughter weight. At the same time, significant ( P < 0.001 or 0.01) increases occurred in each of water intake, water/feed ratio, total body water (mL/100 g body solids), blood urea-N, creatinine, respiration rate and rectal, skin and ear temperatures. The interaction of breed x period effects was significant ( P < 0.01 or 0.05) on plasma creatinine and hind-limb cut. Estimations of 'adaptability' to the subtropical environment of Egypt were found to be 83.1% for NZW and 82.6% for Cal breeds. 相似文献
The moderator band (MB) is a common fibromuscular anatomical structure for the right ventricle of most animals. The histomorphometric and immunohistochemical analysis of the MBs of Egyptian Baladi cattle in relation to age was the aim of this study. Eighteen clinically healthy animals of both sexes were used for this study. The animals were divided into three groups depending on age, group I (N = 4, <1 year), group II (N = 8, 1–2 years) and group III (N = 6, 4–8 years). Cross sections of the MBs from all groups were stained with H&E, Masson's trichrome and anti‐connexin43 (Cx43) antibody for histological and immunohistochemical examinations. Also, measurements for the thickness of the endocardium of the MB as well as, the wall of its muscular artery were conducted. Bundles of Purkinje fibres (PFs) were identified peripherally in the endocardial layer and among the myocardial fibres in the core of each MB. The infiltration of endocardial adipocytes was the characteristic for MBs of old animals. All morphometric data showed a significant increase with the advancement of age. Immunohistochemical findings revealed the localization and distribution of Cx43 in the PFs and intercalated discs of all examined MBs. However, variation of Cx43 immunoreactivity was found among the groups depending on the age. On the basis of this study, this conclusion of different histomorphometry and Cx43 expression of the MBs in relation to age was drawn. These interesting findings provide further insight into age‐related physiological and pathological heart conditions. 相似文献
In this study, we investigated the effects of probiotic, acidifier and synbiotic supplementation on growth performance, mortality rate, intestinal gene expressions, fecal shedding, and organs colonization induced by Escherichia coli in broiler chickens. Six experimental groups were included; negative control group (NC), positive control group (PC), probiotic group (PR), acidifier group (AC), synbiotic group (SY) and colistin sulfate group (CS). Chickens in groups NC and PC were fed a basal diet, while chickens in groups PR, AC, SY, and CS were fed a basal diet containing probiotic, acidifier, synbiotic and colistin sulfate, respectively from the 1st day to the 28th day of age. At 7 days of age, all groups (not NC) were orally challenged with 0.5 ml (1.0?×?109 CFU/ml) E. coli O78. The dietary supplementation of acidifier and synbiotic were sufficient to quell the devastating effects of E. coli infection in broilers. Growth performances represented by body weight gain, feed intake and feed conversion ratio were significantly improved as well as, mortalities were prevented whilst the ileal pro-inflammatory gene expressions (IL-6, IL-8, IL-13, TLR-4, IFN-γ, LITAF, AvBD-2, and AvBD-9) were significantly downregulated and the anti-inflammatory cytokine (IL-10) was significantly increased. In addition, E. coli fecal shedding and organs colonization was significantly diminished. It was concluded that the addition of both acidifier and synbiotic to the diet of broilers infected with E. coli could modulate the intestinal inflammatory responses induced by E. coli infection and minimized the inflammation-induced damage which resulted in improvement in growth performance, prevention of mortalities and reduction of E. coli environmental contamination.
Secondary iodine deficiency was experimentally produced in growing male lambs by oral administration of 50 mg/kg bodyweight of Thiourea daily for 3.5 months. At the end of the experiment the animals became weak, emaciated, anaemic, significantly reduced in body weight with facial oedema and alopecia at thigh, legs and abdomen. The clinical analysis showed significant reduction in erythrocyte and leucocyte numbers and in levels of triiodothyronine and testosterone at the end of the experiment. The histopathological picture of the thyroid gland revealed hyperplasia of the follicle-lining epithelial cells which project into the lumen. The lumens of the follicles are devoid of colloid. The testes showed ill-developed small, empty seminiferous tubulcs. In the liver, the hepatocytes showed degeneration and vacuolation with proliferation of Kupffer cells, which contain haemosiderin pigment. The kidney showed glomerular lipidosis with accumulation of haemosiderin pigment in the cytoplasm of the renal tubules. Hyperkeratosis of the epidermis associated with excessive keratin formation within the hair follicles was detected. In conclusion, deficiency of iodine causes hypothyroidism which leads to retardation of growth, reduced wool production and interferes with sexual maturity of growing male lambs. 相似文献
A fatal disease of sheep and goats in the northern part of China has been reported to be due to Babesia ovis. However, some characteristics of the causative agent in recent reports are not in accordance with the original attributes ascribed to this parasite. Therefore, the 18S small subunit ribosomal RNA (18S rRNA) genes of a number of Babesia isolates in China were sequenced and compared with that of other Babesia and Theileria species in an attempt to clarify their taxonomic position. In the present study, seven Babesia isolates were collected from distinct areas of northern China, and the 18S rRNA genes were amplified and sequenced. The phylogenetic trees were inferred based on 18S rRNA gene sequences of the Chinese ovine Babesia isolates and some of ovine Babesia and Theileria species available in GenBank. In the phylogenetic tree, Babesia sp. isolates from Madang, Tianzhu, Lintan, Ningxian, Hebei and Liaoning all grouped with B. motasi with 88.2-99.9% identity, while Babesia sp. Xinjiang grouped in a separate clade between B. ovis and B. crassa with 79.7-81.2% identity. The results indicated that there are at least two distinct Babesia species groups-B. motasi and Babesia sp. Xinjiang, the latter was distinctly different from other ovine Babesia isolates from China with less than 86.6% identity. 相似文献
The proliferation of peripheral blood mononuclear cells (PBMC) containing both monocyte/macrophages and T lymphocytes increased after treatment with T-cell mitogen (concanavalin A: Con A). PBMC treated with either leptin alone or combination of leptin and ConA showed enhanced proliferative activity by 10-40%, compared with those treated with ConA alone. In contrast, isolated T lymphocytes treated with leptin and ConA showed lowered proliferative activity than the ConA-treated alone, indicating that leptin induced production of some cytokines from monocyte/macrophages, that subsequently resulted in enhancement of T lymphocytes proliferation in PBMC. Among the cytokines examined, monocyte/monocytes constitutively expressed interleukin (IL)-1beta, IL-12p35, IL-18 mRNA, and faintly expressed tumor necrosis factor (TNF)-alpha and IL-12p40 mRNA. Leptin treatment augmented the monocyte/macrophages mRNA expression of only TNF-alpha and IL-12p40 to comparable levels of cells treated with lipopolysaccharide (LPS). However, leptin treatment increased monocyte/macrophages production of IL-1beta as well as TNF-alpha, and induced the mRNA expression of caspase-1, which is shown to mediate the conversion of latent pro-IL-1beta and pro-IL-18 to active forms. These results suggest that leptin directly acts on monocyte/macrophages to produce factors that induce T lymphocytes proliferation such as IL-12p35/p40 complex through IL-12p40 induction and IL-1beta/IL-18 production through caspase-1 induction. 相似文献