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OBJECTIVEDuring diabetes, retinal microglial cells are activated to release inflammatory cytokines that initiate neuronal loss and blood–retinal barrier breakdown seen in diabetic retinopathy (DR). The mechanism by which diabetes activates microglia to release those inflammatory mediators is unclear and was therefore elucidated.RESEARCH DESIGN AND METHODSMicroglia activation was characterized in streptozocin-injected rats and in isolated microglial cells using immunofluorescence, enzyme-linked immunosorbent assay, RT-PCR, and Western blot analyses.RESULTSIn 8-week diabetic retina, phospho-extracellular signal–related kinase (ERK) and P38 mitogen-activated protein kinases were localized in microglia, but not in Mueller cells or astrocytes. At the same time, Amadori-glycated albumin (AGA)-like epitopes were featured in the regions of microglia distribution, implicating a pathogenic effect on microglial activation. To test this, diabetic rats were treated intravitreally with A717, a specific AGA-neutralizing antibody, or murine IgG. Relative to nondiabetic rats, diabetic rats (IgG-treated) manifested 3.9- and 7.9-fold increases in Iba-1 and tumor necrosis factor (TNF)-α mRNAs, respectively. Treatment of diabetic rats with A717 significantly attenuated overexpression of these mRNAs. Intravitreal injection of AGA per se in normal rats resulted in increases of Iba-1 expression and TNF-α release. Guided by these results, a cultured retinal microglia model was developed to study microglial response after AGA treatment and the mechanistic basis behind this response. The results showed that formation of reactive oxygen species and subsequent activation of ERK and P38, but not Jun NH2-terminal kinase, are molecular events underpinning retinal microglial TNF-α release during AGA treatment.CONCLUSIONSThese results provide new insights in understanding the pathogenesis of early DR, showing that the accumulated AGA within the diabetic retina elicits the microglial activation and secretion of TNF-α. Thus, intervention trials with agents that neutralize AGA effects may emerge as a new therapeutic approach to modulate early pathologic pathways long before the occurrence of vision loss among patients with diabetes.

Purpose Cannabidiol (CBD), a non-psychotropic, non-toxic compound has been shown to block diabetes- and endotoxin-induced retinal damage. However, the protective mechanism of this anti-inflammatory cannabinoid is not completely understood. The goal of this study is to determine the role of adenosine signaling in retinal inflammation and its potential modulation by CBD. Methods The adenosine receptor (AR) subtypes expressed in rat retinal microglial cells was assessed by quantitative real-time RT-PCR. AR function was determined via in vitro and in vivo inflammatory models. Microglial cells or rats were treated with or without lipopolysaccharide (LPS) in the presence or absence of adenosine, adenosine receptor agonists/antagonists, or CBD. Adenosine uptake and tumor necrosis factor-α (TNF-α) release in cells or in retinas were determined. Results Our results showed that A2AARs are abundantly expressed in rat retinal microglial cells. Upon treating the cells or rats with LPS, activation of the A2AAR was the most efficient in mediating AR agonist- or CBD-induced TNF-α inhibition. CBD inhibited adenosine uptake via equilibrative nucleoside transporter 1 and synergistically enhanced adenosine's TNF-α suppression upon LPS treatment. Conclusions These results suggest that the activated A2AAR in the retinal microglial cells plays a major role in anti-inflammation in the retina, and that CBD anti-inflammatory effects are linked to adenosine uptake inhibition.

A total of 2000 Hubbard Classic females and 180 males (male to female ratio 1:11) close to standard body weights were selected and managed separately in the same shed. The objective of this experiment was to study the effects of egg size (small, medium and large) at mid (45 weeks) production cycle and flock age (30, 45 and 60 weeks old) on hatching egg weight loss, fertility, hatchability traits, chick weight and chick yield in a commercial Hubbard Classic broiler breeder flock. The results showed that minimum egg weight loss (P ≤ 0.05) was recorded in large egg size group at different incubation periods and egg weight losses decreased with advancing the age of breeder hens. Maximum fertility and hatchability (P ≤ 0.05) was noticed in small egg size group, followed by medium and large egg size groups. However, maximum embryonic mortality (P ≤ 0.05) during incubation and higher percentage of infertile eggs was recorded in large size egg group, followed by medium and small egg size groups. Low fertility, hatchability was recorded (P ≤ 0.05) in older hen at the age of 60 weeks. The chick weight and chick length were amplified (P ≤ 0.05) with increasing the egg size. However, egg size was not influenced (P ≥ 0.05) on chick yield. The chick weight, chick yield and chick length were improved (P ≤ 0.05) with advancing age of broiler breeder.

Insects are considered as a potential substitute for fishmeal (FM) and soybean meal (SBM) in feeding mixtures for poultry diets. The intent of this paper is to appraise the current work relating to the use of insects as alternative protein in poultry feeding and the potential of large production of insects for the poultry feed industry. Certainly insects have a mammoth prospective as a protein source and other active substances (i.e. polyunsaturated fatty acids, antimicrobial peptides) for poultry. On the basis of numerous studies, insects meal belonging to the orders Diptera (black soldier fly, housefly), Coleoptera (mealworms), Megadrilacea (earthworm), Lepidoptera (silkworm and cirina forda) and Orthoptera (grasshoppers, locust and crickets), may be fruitfully used as feed ingredient in poultry diets. Information regarding their nutritional composition and biological evaluation was collected and compared it to SBM and FM.ARTICLE HISTORY

A study was conducted to evaluate enzyme and probiotic feed supplements as alternative feed additives to alleviate the problems associated with the withdrawal of antibiotics from layer diet. A total of 180 Hy-Line W-98 hens, 40 weeks old, were assigned into four treatment groups so that there were 45 laying hens in each group. Four dietary treatments were randomly assigned to the four groups of hens. Hens in Group 1 were fed basal diet only (negative control), Group 2 was fed basal diet ' antibiotic at a level of 2.0 g/kg (positive control), Group 3 was fed basal diet ' multi-enzyme at a level of 2.0 g/kg (ES) and Group 4 was fed basal diet ' multi-species probiotic at a level of 0.5 g/kg (PS). The results showed that addition of either enzyme or probiotic supplementation to the basal diet significantly increased the egg production, egg weight and egg mass of hens than the negative control group. There was no significant difference in feed intake among treatments, although the feed conversion improved with the addition of antibiotic, enzyme and probiotic than the negative control. Over the 70-day trial period, weight gain was higher than the negative control for birds fed the diet containing probiotic. There was no significant effect on mortality during the study. Haugh unit score was significantly increased in the groups fed the ES and PS diets when compared with negative control group. Egg shape index, specific gravity, yolk index, shell weight, shell thickness and damaged eggs did not differ significantly among the laying hens of all dietary groups. High-density lipoprotein-cholesterol was significantly increased by probiotic supplementation compared with other dietary groups. Dietary treatments did not influence eosinophils and monocytes, increased lymphocyte and decreased heterophil and H:L ratio. The geometric means haemagglutination inhibition titres of birds fed on diets containing antibiotic, enzyme and probiotic supplementation were higher from 28 to 70 days than that of negative control. It may be concluded that the supplementation of enzyme and probiotic in layer diets did not appear to cause any adverse effects on egg production, egg quality and immunity compared with the negative control laying hens and non-antibiotic feed additives can be used as alternative. Moreover, the dietary supplementation of probiotic may lead to the development of low-cholesterol chicken eggs as demanded by health-conscious consumers.

A study was conducted to evaluate the effect of 3 different levels (1.25, 2.5 or 5.0%) of black cumin seeds (BCS) on five hundred chicks. A basal diet was supplemented with either 0 (negative control), or 0.1% antibiotic (positive control), or 3 levels of BCS. At day 28 and 42 of age, the 2.5 and 5.0% BCS groups had significantly greater body weight gain (BWG) than the 1.25% BCS and the antibiotic group. The same groups had feed efficiency significantly improved (P<0.05) compared to the 1.25% BCS group and the controls. At both ages, measurement of the dressing percentage showed no marked variation between BCS supplementation and antibiotic. The 2.5 and 5.0% BCS groups showed an increase (P<0.05) in total protein and higher (P<0.05) haematological values than the 1.25%, antibiotic or unsupplemented diet group. The activities of blood enzymes were lower (P<0.05) and caecal coliform and Escherichia coli populations decreased (P<0.05) in BCS and antibiotic groups. Serum and tissue cholesterol concentration decreased (P<0.05) as the levels of BCS increased. The geometric means haemagglutination inhibition (HI) titres of the BCS and the antibiotic group were always higher than the negative control. The mean lymphoid organs weight/body weight ratio of the negative control was significantly (P<0.05) lower than BCS and antibiotic groups. In conclusion, including up to 2.5 or 5.0% BSC in the diets of broilers has no deleterious effects on their performance, immunity, serum biochemical constituents nor haematological indices. In fact, it may lead to the development of low-cholesterol chicken meat

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