Modulating the Growth, Antioxidant Activity, and Immunoexpression of Proinflammatory Cytokines and Apoptotic Proteins in Broiler Chickens by Adding Dietary Spirulina platensis Phycocyanin

Shared genetic links between hypothyroidism and psychiatric disorders: evidence from a comprehensive genetic analysis

Background

Epidemiologic studies have suggested co-morbidity between hypothyroidism and psychiatric disorders. However, the shared genetic etiology and causal relationship between them remain currently unclear.

Methods

We assessed the genetic correlations between hypothyroidism and psychiatric disorders [anxiety disorders (ANX), schizophrenia (SCZ), major depressive disorder (MDD), and bipolar disorder (BIP)] using summary association statistics from genome-wide association studies (GWAS). Two disease-associated pleiotropic risk loci and genes were identified, and pathway enrichment, tissue enrichment, and other analyses were performed to determine their specific functions. Furthermore, we explored the causal relationship between them through Mendelian randomization (MR) analysis.

Results

We found significant genetic correlations between hypothyroidism with ANX, SCZ, and MDD, both in the Linkage disequilibrium score regression (LDSC) approach and the high-definition likelihood (HDL) approach. Meanwhile, the strongest correlation was observed between hypothyroidism and MDD (LDSC: rg=0.264, P=7.35×10-12; HDL: rg=0.304, P=4.14×10-17). We also determined a significant genetic correlation between MDD with free thyroxine (FT4) and thyroid-stimulating hormone (TSH) levels. A total of 30 pleiotropic risk loci were identified between hypothyroidism and psychiatric disorders, of which the 15q14 locus was identified in both ANX and SCZ (P values are 6.59×10-11 and 2.10×10-12, respectively) and the 6p22.1 locus was identified in both MDD and SCZ (P values are 1.05×10-8 and 5.75×10-14, respectively). Sixteen pleiotropic risk loci were identified between MDD and indicators of thyroid function, of which, four loci associated with MDD (1p32.3, 6p22.1, 10q21.1, 11q13.4) were identified in both FT4 normal level and Hypothyroidism. Further, 79 pleiotropic genes were identified using Magma gene analysis (P<0.05/18776 = 2.66×10-6). Tissue-specific enrichment analysis revealed that these genes were highly enriched into six brain-related tissues. The pathway analysis mainly involved nucleosome assembly and lipoprotein particles. Finally, our two-sample MR analysis showed a significant causal effect of MDD on the increased risk of hypothyroidism, and BIP may reduce TSH normal levels.

Conclusions

Our findings not only provided evidence of a shared genetic etiology between hypothyroidism and psychiatric disorders, but also provided insights into the causal relationships and biological mechanisms that underlie their relationship. These findings contribute to a better understanding of the pleiotropy between hypothyroidism and psychiatric disorders, while having important implications for intervention and treatment goals for these disorders.

Algae as an alternative source of protein in poultry diets for sustainable production and disease resistance: present status and future considerations

Integrating algae into poultry diets offers a promising avenue for enhancing nutrition, boosting sustainability efforts, and potentially stimulating disease resistance. This comprehensive review delves into the essence, diversity, chemical composition, and nutritional merits of algae, spotlighting their emergence as innovative nutrient sources and health supplements for poultry. The growing interest in algae within poultry nutrition stems from their diverse nutritional profile, boasting a rich array of proteins, lipids, amino acids, vitamins, minerals, and antioxidants, thus positioning them as valuable feed constituents. A key highlight of incorporating both macroalgae and microalgae lies in their elevated protein content, with microalgae varieties like Spirulina and Chlorella exhibiting protein levels of up to 50-70%, outperforming traditional sources like soybean meal. This premium protein source not only furnishes vital amino acids crucial for muscular development and overall health in poultry but also serves as an exceptional reservoir of omega-3 fatty acids, notably eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), presenting multiple health benefits for both poultry and consumers alike. Moreover, algae boast antioxidant properties attributed to bioactive compounds like phycocyanin and astaxanthin, mitigating oxidative stress and boosting the bird's immune response, thereby fostering robust health and disease resilience. Incorporating macroalgae and microalgae into poultry diets yields positive impacts on performance metrics. Research evidence underscores the enhancement of growth rates, feed conversion ratios, carcass quality, and meat attributes in broilers, while in layers, supplementation promotes increased egg production, superior egg quality, and increased concentrations of beneficial nutrients such as omega-3 fatty acids. Furthermore, algae hold promise for mitigating the environmental footprint of poultry production, though significant outcomes from trials remain sporadic, necessitating further research to elucidate optimal dosages and blends for different algae species in poultry diets. Standardizing the composition of algae utilized in research is imperative, paving the way for potential applications in poultry nutrition as growth stimulants and substitutes for antibiotics. Nonetheless, a deeper understanding of dosage, combination, and mechanism of action through rigorous scientific investigation is key to unlocking algae's full potential within poultry nutrition.

Improving performance, reproduction, and immunity in laying Japanese quail with algal derivatives

We investigated the effect of the Persian Gulf algae derivatives, namely phycocyanin (PC) and fucoidan (FUC), on the performance, reproductive traits, and immune responses of laying Japanese quails. A completely randomized design was used to distribute 250 six-wk-old Japanese quails with an average body weight of 215 ± 10 g into 5 treatments, 5 replicates, and 10 birds in each replicate over a 5-wk period. Unlike the control groups, the treatment groups received drinking water supplemented with PC and FUC at concentrations of 20 or 40 mg/L, denoted as PC20, PC40, FUC20, and FUC40, respectively, while all birds were provided with identical feed. Supplemental algal derivatives notably improved hen day egg production (HDEP), egg mass, and feed conversion ratio (FCR) compared to the control group (P < 0.01). Incorporating PC and FUC had no significant effect on the weight of males' testes or the weight and length of hens' oviducts. Additionally, the experimental treatments had no impact on the chicks' hatching weight. The supplementation of PC and FUC resulted in increased fertility (P = 0.038) and hatchability (P < 0.001) rates, with the exception of fertility in the PC40 group. The effect of the experimental treatments on immune responses was largely not statistically significant, except in the case of ND. Specifically, the experimental treatments resulted in increased (P = 0.033) antibody titers against ND when compared to the control group, with the exception of FUC20. Supplemental algal derivatives significantly (P < 0.01) reduced total cholesterol, creatinine, and triglycerides (except in the case of PC20). Overall, these findings underscore the potential of algal derivatives to enhance quail performance, reproductive traits, and immune responses.

Evaluating the effect of Spirulina platensis on the immune response of broiler chickens to various vaccines and virulent Newcastle disease virus challenge

This study investigated the efficacy of co-administration of Spirulina platensis (SP) with vaccines on the immune response to Avian influenza (AI), Infectious bronchitis (IB), and Newcastle disease (ND), along with I/M challenging by virulent ND virus (vNDV) genotype VII. 126 one-day-old broiler chicks were allocated into six groups (21 birds/group with three replicates): G1: negative control; G2: positive control; G3: vaccinated, non-SP-supplemented; G4: vaccinated, SP-supplemented (0.1%); G5: vaccinated, SP-supplemented (0.3%); and G6: vaccinated, SP-supplemented (0.5%). G2-6 were challenged with a velogenic NDV genotype VII virus. Dietary SP administration prevented the ND-induced mortality compared to G2 (52.4%) and G3 (14.3%), in addition to alleviating the clinical disease. G3-6 showed significant improvement in body weight loss% and FCR during two weeks post vNDV challenge (pc), and the overall FCR (2.64 ± 0.28, 1.56 ± 0.03, 1.60 ± 0.05, 1.53 ± 0.04, and 1.54 ± 0.03 for G2, 3, 4, 5 and 6, respectively) (P<0.05). On the challenging day, the ND-HI titer (log2) of G3 (5.44 ± 0.24) was numerically higher than G6 (4.20 ± 0.55) and lower than G4 (6.10 ± 0.34) and G5 (6.00 ± 0.28). On the 10th day pc, ND-HI titer in G4-6 was numerically lower in a dose-dependent manner than that of G3, suggesting an antiviral efficacy of SP. G4-6 had lower viral shedding titer than G2 and G3 (P<0.05). In G3-6, viral shedding was reduced by 15, 27, 24, and 33.6%, respectively. In addition, the histopathological lesions in the trachea, lung, and spleen were severe in G2, moderately reduced in G3, and more relieved in G4-6. At three weeks after vaccination, the HI antibody titer of AIH5 was significantly higher after SP administration, especially at the 0.3% level, compared to the vaccine alone (P<0.05), demonstrating an immune-stimulating effect. In conclusion, dietary administration of SP, particularly a dose of 0.3%, for vaccinated chickens against NDV exerted an antiinflammatory and antiviral effects by preventing deaths, alleviating clinical disease and weight loss, and decreasing viral shedding post heterologous NDV challenge.

Phycocyanin as a nature-inspired antidiabetic agent: A systematic review

BACKGROUND

Nutraceuticals have been important for more than two decades for their safety, efficacy, and outstanding effects. Diabetes is a major metabolic syndrome, which may be improved using nutritional pharmaceuticals. Some microalgae species, such as spirulina, stand out by providing biomass with exceptional nutritional properties. Spirulina has a wide range of pharmacological effects, mostly related to phycocyanin. Phycocyanin is a protein compound with antidiabetic properties, known as a nutraceutical.

OBJECTIVE

This review delves into phycocyanin applications in diabetes and its complications and ascertains the mechanisms involved.

METHODS

Scopus, PubMed, Cochrane Library, Web of Science, and ProQuest databases were systematically reviewed (up to April 30, 2023), in which only animal and cellular studies were found.

RESULTS

According to animal studies, the administration of phycocyanin affected biochemical parameters (primary outcome) related to diabetes. These results showed an increase in fasting insulin serum and a decrease in fasting blood glucose, glycosylated serum protein, and glycosylated hemoglobin. In cellular studies, though, phycocyanin prevented methylglyoxal and human islet amyloid polypeptide-induced dysfunction in β-cells and induced apoptosis through different molecular pathways (secondary outcome), including activation of Nrf2, PI3K/Akt, and suppression of JNK and p38. Also, phycocyanin exerted its antidiabetic effect by affecting the pathways regulating hepatic glucose metabolism.

CONCLUSIONS

Thus, based on the available information and literature, targeting these pathways by phycocyanin may unleash an array of benefits, including positive outcomes of the antidiabetic effects of phycocyanin as a nutraceutical.

OTHER

This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) at the National Institute of Health. The registration number is CRD42022307522.

New Insights into the Effects of Microbial Muramidase Addition in the Diets of Broiler Chickens

The study aimed to explore how broiler chickens' blood biochemistry, breast muscles' fatty acid profile, growth, intestinal morphology, and immune status would be influenced by adding microbial muramidase (MUR) to the diet. Four hundred 3-day-old male broiler chickens were allocated to a completely randomized design consisting of four nutritional treatments (n = 100 per treatment, 10 chicks/replicate), each containing MUR at levels of 0 (control group), 200, 400, and 600 mg Kg^-1 diet, with enzyme activity 0, 12,000, 24,000, and 36,000 LSU(F)/kg diet, respectively. The 35-day experiment was completed. The findings showed that adding MUR to broiler meals in amounts of 200, 400, or 600 mg/kg had no impact on growth performance (p > 0.05) during the periods of 4-10, 11-23, and 24-35 days of age. MUR supplementation quadratically impacted the feed conversion ratio of broiler chicks at 11 and 23 days of age (p = 0.02). MUR addition to the diet significantly and level-dependently enhanced the percentage of n-3 and n-6 polyunsaturated fatty acids (PUFA) in breast muscles (p ≤ 0.01), with no alterations to the sensory characteristics of the breast muscles. Dietary MUR increased most of the morphometric dimensions of the small intestine, with the best results recorded at the 200 and 400 mg Kg^-1 levels. MUR supplementation at 200, 400, and 600 mg kg^-1 linearly lowered the total cholesterol, triglycerides, and low-density lipoprotein cholesterol level (p < 0.01). Still, it significantly increased the high-density lipoprotein cholesterol and very-low-density lipoprotein cholesterol contents compared with the unsupplemented group. Compared to controls, there was a substantial rise in the blood concentration of total protein, albumin, globulin, IL10, complement 3, and lysozyme activity as MUR levels increased (p < 0.01). Moreover, MUR addition significantly increased the immunoexpression of lymphocyte subpopulation biomarkers. We could conclude that MUR can be added to broiler chicken diets up to 600 mg kg ^-1 to improve broiler chickens' fatty acid profile in breast muscles, immunity, and blood biochemistry. MUR addition had no positive influence on the bird's growth.

Dietary 1,3-β-Glucans Affect Growth, Breast Muscle Composition, Antioxidant Activity, Inflammatory Response, and Economic Efficiency in Broiler Chickens

Recently, researchers have been intensively looking for novel, safe antibiotic alternatives because of the prevalence of many clinical and subclinical diseases affecting bird flocks and the risks of using antibiotics in subtherapeutic doses as feed additives. The present study intended to evaluate the potential use of 1,3-β-glucans (GLC) as antibiotic alternative growth promotors and assessed the effect of their dietary inclusion on the growth performance, carcass traits, chemical composition of breast muscles, economic efficiency, blood biochemical parameters, liver histopathology, antioxidant activity, and the proinflammatory response of broiler chickens. This study used 200 three-day-old ROSS broiler chickens (50 chicks/group, 10 chicks/replicate, with an average body weight of 98.71 ± 0.17 g/chick). They were assigned to four experimental groups with four dietary levels of GLC, namely 0, 50, 100, and 150 mg kg−1, for a 35-day feeding period. Birds fed diets containing GLC showed an identical different growth rate to the control group. However, the total feed intake (TFI) increased quadratically in the GLC50 and GLC100 groups as compared to that in the control group. GLC addition had no significant effect on the weights of internal and immune organs, except for a decrease in bursal weight in the GLC150 group (p = 0.01). Dietary GLC addition increased the feed cost and total cost at 50 and 100 mg kg−1 doses. The percentages of n-3 and n-6 PUFA in the breast muscle of broiler chickens fed GLC-supplemented diets increased linearly in a dose-dependent manner (p < 0.01). The serum alanine aminotransferase (ALT) level and the uric acid level were quadratically increased in the GLC150 group. The serum levels of total antioxidant capacity, catalase, superoxide dismutase, interleukin-1β, and interferon-gamma linearly increased, while the MDA level decreased in the GLC-fed groups in a dose-dependent manner. Normal histological characterization of different liver structures in the different groups with moderate round cells was noted as a natural immune response around the hepatic portal area. The different experimental groups showed an average percentage of positive immunostaining to the proinflammatory marker transforming growth factor-beta with an increase in the dose of GLC addition. The results suggest that GLC up to 100 mg kg−1 concentration can be used as a feed additive in the diets of broiler chickens and shows no adverse effects on their growth, dressing percentage, and internal organs. GLC addition in diets improves the antioxidant activity and immune response in birds. GLC help enrich the breast muscle with n-3 and n-6 polyunsaturated fatty acids.

The Effects of Dietary Spirulina platensisis on Physiological Responses of Broiler Chickens Exposed to Endotoxin Stress

This study was proposed to highlight the impact of dietary Spirulina platensis (SP) supplementation in alleviating the deterioration effect of Escherichia coli (EC) on the growth performance, redox biomarkers, immune reaction, and hindgut microbial counts and acidosis in broiler chickens. Four hundred Cobb500, one-day-old, broiler chickens were deposited in battery cages (10 chicks per cage). The chicks were distributed into totally randomized 2 × 2 factorial treatments (10 replicate cages per treatment) from the day 22 to the day 42 of age. Birds of two of the groups were fed on a basal diet without SP supplementation (-SP groups), while birds of the other two groups were fed on a basal diet supplemented with 10 g/kg SP (+SP groups). At day 36th of age, birds in one of the -SP and +SP groups were challenged by an intraperitoneal (i.p.) injection with 10⁷ CFU/bird EC (O157:H7 strain) in 0.5 mL sterilized saline (+EC groups), whereas the other non-challenged groups were i.p. injected with 0.5 mL saline only (-EC groups). The current study results indicated that the boilers challenged with EC had a significant (p < 0.05) lower performance, poor antioxidant activity, immunosuppression, and higher numbers of pathogenic bacteria in the intestine when compared with the non-challenged birds. Dietary SP inclusion enhanced (p < 0.05) broiler growth, antioxidant activity, immune response, and intestinal beneficial bacteria and acidosis. Moreover, SP alleviated the reduction in all these parameters after exposure to EC infection. Therefore, diets containing 10 g/kg SP could be used as a promising approach to maximize broilers' production and support their health, particularly when challenged with EC infection.

The impact of multi-enzyme fortification on growth performance, intestinal morphology, nutrient digestibility, and meat quality of broiler chickens fed a standard or low-density diet

This research aimed to study the impact of supplementation of three multi-enzyme levels (0, 0.1, and 0.2% of feed) and two levels of dietary treatments [standard diet (SD) and low-density diet (LDD)] on growth performance, carcass traits, digestibility, and meat quality of broilers from 1 to 38 days of age. A total of 216 1-day-old Arbor Acres broiler chicks were randomly assigned to a factorial experiment (2 × 3) comprising six dietary treatments, each with six replicates and each replicate with six chickens. The results showed that the LDD significantly reduced body weight gain by 5.0%, compared with the SD. Multi-enzymes significantly improved body weight gain and the production index (PI) relative to the SD. The feed conversion ratio was significantly enhanced with increased multi-enzymes from 1 to 21 days. A significant relation between the multi-enzyme concentration and type of dietary treatment was observed in body weight gain and feed conversion ratio from 1 to 21 days of age. Nitrogen-free extract digestibility was significantly increased by using the SD diet compared with using the LDD. Multi-enzyme supplementation improved the digestibility of dry matter, crude protein, crude fiber, and nitrogen-free extract in the LDD. A significant relationship was found between the multi-enzyme concentration and type of dietary treatment on the pancreas, liver, and intestinal length percentages. The meat dry matter concentration was significantly higher in the LDD group than in the SD group. The low-density diet significantly reduced the total revenue compared with the SD, whereas broilers fed the SD recorded significantly higher total revenue and economic efficiency than those fed the LDD. The low-density diet significantly increased economic efficiency compared with the SD. Multi-enzymes significantly increased the total revenue, net revenue, and economic efficiency than the standard set. In conclusion, using multi-enzymes in broiler diets improved body weight gain. The LDD with multi-enzymes showed enhanced body weight gain compared with the SD without multi-enzymes.

Effect of Dietary Microalgae (Spirulina platensis) on Growth Performance, Ingestive Behavior, Hemato-Biochemical Parameters, and Economic Efficiency of Fayoumi Broilers

This study was conducted to evaluate the effect of dietary supplementation with Spirulina platensis (SP) on the productive performance, carcass characteristics, behavior, blood serum metabolites, hematological indices, and economic efficiency of Fayoumi broiler chickens for a 56-day. In total, 120 one-day-old broiler chicks were randomly distributed among four dietary treatments with three replicates (n = 10/group) for 8 weeks. The dietary treatments were a control basal diet without SP and the same basal diets supplemented with 0.25, 0.5, or 1.0% SP. Birds fed 1% Spirulina-supplemented diets recorded significantly (p < 0.05) higher body weight, weight gain, and feed conversion ratio and less overall feed intake and feeding behavior than those in the control group. No significant changes (p > 0.05) were recorded in the dressing percentage or the relative weights of internal organs among the different experimental groups, except for the thymus. Diets containing 0.5 or 1.0% SP saw an increase (p < 0.05) in serum total protein and globulin and a reduction (p < 0.05) in serum cholesterol concentration. The lymphocyte percentage in birds fed SP diets was significantly (p < 0.05) higher than in birds fed the control diet. These results suggest that adding SP up to 1% to the broiler diets could positively affect some important blood biochemical parameters, enhance their immunity response, and improve their growth performance. However, from an economic point of view, supplementation with 0.25% of SP is recommended for Fayoumi broiler chickens.

Effect of Dietary Blue-Green Microalgae Inclusion as a Replacement to Soybean Meal on Laying Hens' Performance, Egg Quality, Plasma Metabolites, and Hematology

Spirulina platensisis (SP) is a blue-green microalgae with a high value for animal and poultry nutrition. The study employed 250 40-week-old, HY-Line W-36 commercial laying hens. The layers received one of five experimental diet substitutes in five groups for 10 consecutive weeks (five replicates of 10 hens each group); a soybean-corn basal diet formulation without SP (Control group) or the soybean partially substituted with 3% SP, 6% SP, 9% SP, and 12% SP (for the remaining four groups). The results showed that dietary SP treatment significantly (p < 0.05) improved the productive performance, egg quality, blood metabolites, and hematological parameters of laying hens. In addition, there were linear and quadratic effects for increasing the levels of SP inclusion into the layer diets; however, the highest values of most parameters were observed when using 9% SP (90 g/kg of the layer diets). Furthermore, the results showed that 4.7% of the soybean meal ingredient in the layer diet could be replaced by 1% of SP. In conclusion, the partial replacement of soybean meal by SP into layer diets could be used as a promising nutritional approach to optimize the performance of laying hens.

The relation between avian coronaviruses and SARS-CoV-2 coronavirus

The coronaviruses (CoVs) are a family of ribonucleic acid viruses that are present in both mammals and birds. SARS-CoV and MERS-CoV originated in bats, and there is a possibility that this could be the case for SARS-CoV-2 as well. There is already evidence that a probable intermediary host is responsible for the emergence of viruses in humans as was the case for SARS-CoVs and MERS-CoV. As the SARS-CoV-2 originated from a live animal market, there is always the question if domestic animals are susceptible to these viruses and the possible risk of zoonotic transmission with mammals, including humans. This uncertainty of the transmission of the COVID-19 virus between humans and animals is of great significance worldwide. Hence, this paper focuses on the avian CoVs and their possible relation and interaction with SARS-CoV-2.

Impact of Dietary Lavender Essential Oil on the Growth and Fatty Acid Profile of Breast Muscles, Antioxidant Activity, and Inflammatory Responses in Broiler Chickens

This study aimed to investigate the impact of dietary addition of lavender essential oil (Lavandula angustifolia L.) (LEO) on the growth performance, tissue histoarchitecture, and fatty acid profile in breast muscles, as well as blood biochemistry and immune expression of pro-inflammatory cytokines of broiler chickens. A total of 200 three-day-old broiler chickens (average body weight 101.3 ± 0.24 g) were assigned to a completely randomized design consisting of four dietary treatments (n = 50 per treatment, each replicate consisting of 10 birds) that included lavender essential oil at concentrations of 0 (control group), 200, 400, and 600 mg Kg−1 diet. The experiment lasted for 35 days. The results revealed that supplementation of lavender essential oil at 200, 400, or 600 mg/kg in broiler diets had no effect (p > 0.05) on the growth performance throughout the experimental periods (3−10, 11−23, and 24−35 days of age). According to the broken line regression model, the optimal level for dietary LEO addition was the 460 mg kg−1 diet based on the total body weight gain and feed conversion ratio results. The diets supplemented with lavender essential oil had no effect (p > 0.05) on the percentages of carcass yield or internal organs. Dietary addition of LEO significantly increased the percentages of omega-3 polyunsaturated fatty acids PUFA (n-3), omega-6 polyunsaturated fatty acids (n-6), and the n-3/n-6 ratio (p < 0.05) in the breast muscles of chickens in a level-dependent manner. The blood concentration of alanine aminotransferase was significantly increased in lavender essential oil at 600 mg kg−1 compared with other treatments. The dietary addition of LEO at 200, 400, and 600 mg kg−1 significantly reduced the malondialdehyde level. Still, they significantly increased the serum enzyme activities of total antioxidant capacity, catalase, superoxide dismutase, and the pro-inflammatory cytokine (interleukine-1 beta and interferon γ) compared with the unsupplemented group. The LEO-supplemented groups showed normal liver histomorphology as in the control group. However, the immunoexpression of the pro-inflammatory cytokine transforming growth factor β was significantly increased by increasing the level of LEO. It can be concluded that lavender essential oil can be included in broiler chicken diets up to 460 mg kg −1 with no positive effect on the bird’s growth. It can improve the antioxidant capacity and enrich the breast muscles with PUFA. An increased level of supplementation (600 mg kg−1) increased the inflammatory responses in broiler chickens.