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Current vaccination strategies for commercial poultry using live attenuated and inactivated Newcastle disease (ND) vaccines have some limitation and difficulties, and new vaccines with distinct features are needed. Recently, in ovo vaccination technology is concerned as a safe, efficacious, and convenient method. Common ND vaccines used in chickens cannot be employed in ovo due to embryo toxicity and high early mortality. One of the agents that may lead to attenuate ND virus (NDV) strains is aluminum hydroxide (AH) as an adjuvant. The objective of this study was to evaluate AH ability to attenuate NDV for in ovo administration of commercial pullets. Three hundred sixty fertile eggs of a Bovans strain as a factorial arrangement of six doses of the ND vaccine (50% egg infectious (EID50) of 0, 102, 103, 104, 105, and 106) with or without AH were ordered into 12 groups. At 18 d of incubation 0.1 mL of the inoculums was injected into the amniotic fluid of eggs. On the farm, each treatment group was further subdivided into two groups and one of these groups received ND-B1 vaccine on day seven post-hatch. Lowest hatchability was recorded in groups vaccinated with doses of 105 and 106 EID50. On day 21, the highest hem agglutination inhibition (HI) was detected for group vaccinated with dose 102 EID50. Furthermore, hatchability and ND-HI titer were found to be up for pullets received AH in ovo on day 42 posthatch. The results of this study indicated that aluminum hydroxide as an adjuvant could significantly improve hatchability and immune efficacy of pullets when used in ovo. Further, lentogenic VG/GA strain-Avinew will have the potential for application as in ovo vaccine against Newcastle disease, if the vaccine is prepared with sufficient dose.

In this experiment, the effects of fennel and thyme extracts with and without flaxseed were investigated on performance and egg quality of Leghorn-type laying hens (Hy-Line W-36). 200 laying hens from 26 to 38 weeks of age were assigned to five dietary treatments with five replications. The treatment groups were: 1) Control (a diet without any additives); 2) control diet plus fennel (40 mg/kg feed); 3) control diet plus thyme (40 mg/kg feed); 4) a diet containing flaxseed and fennel; and 5) a diet containing flaxseed plus thyme. There were significant differences in feed intake and egg weight between the treatments (P < 0.05). The egg yolk color index in hens that received thyme extract and flaxseed treatment was significantly higher than other treatments (P < 0.05). Hens fed control diet had lower Haugh unit compared to other treatments that contained herbal extracts. The eggshell strength was significantly higher in hens that received thyme extract and flaxseed treatments than control (P < 0.05). The eggshell weight in treatments containing flaxseed was significantly higher compared to the other treatments (P < 0.05). The lowest egg yolk cholesterol concentration was found in hens fed thyme and flaxseed treatment. The hens fed plant extracts and flaxseed diets had eggs with low palmitic and stearic acids and high α-linolenic acid. It is concluded that thyme and fennel extracts, as well as flaxseed, improved the performance and egg quality of laying hens. The use of flaxseed and thyme extract improved egg yolk omega-3 fatty acids and decreased yolk cholesterol content.

The effects of organic and inorganic sources and concentration (0 and 0.3 mg per kg of diet) of Selenium (Se) on growth performance, blood biochemical and immune system were evaluated in broiler chickens. Chickens were fed corn-soy-based diets formulated to 8 dietary treatments containing no added Se (negative control), negative control plus yeast (positive control), and 6 diets had 0.3 mg/kg of diet supplemented with Se from Availa Se, Sel-plex, SeleMax, Se enriched yeast, sodium selenite and sodium selenate. Four hundred Ross 308 male chickens were randomly divided into 8 treatments and 5 replicates of 10 birds each. Feed intake, body weight gain, and feed conversion ratio were measured at starter (0-10 d), grower (11-24 d), and finisher (25-42 d) periods. On d 24 and 42, one bird from each replicate was killed by cervical dislocation and blood samples were collected to determine blood chemicals, glutathione peroxidase (GPx) activity and heterophile to lymphocyte ratio. Results showed that Se supplementation had no effect on feed intake, body weight gain, and feed conversion ratio of the chickens (P < 0.05). However, blood triglycerides, GPx activity and heterophile to lymphocyte ratio were significantly affected by organic and inorganic Se sources (P < 0.05). Results showed that selenium in organic and inorganic forms didn't have any effect on growth performance and blood parameters but they could improve immune system through increase in GPx activity.

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The availability of plant phosphorus in the gut chicken can be improved by increasing phosphorus retention using phytase enzyme or a probiotic with phytase activity as an alternative. In this study, the efficacy of a recombinant probiotic, Lactococcus lactis (L. lactis), with a potential of phytase production was evaluated in broiler chickens. To this aim, 360 one-day-old male broiler Cobb 500 were divided into six treatments with six replicates and reared to 42 days of age. The experimental treatments included positive control diet containing adequate phosphorus (PC), negative control diet containing reduced available phosphorus (NC), negative control diet involving recombinant L. lactis (RLL), negative control diet containing both recombinant L. lactis and Lactobacillus salivarius (RLL + LBS), negative control diet including non-recombinant L. lactis (LL) and negative control diet containing Hostazym ® . Growth performance, total tract apparent disappearance of phytate-P and nutrient retention, mineral content of the tibia and histomorphology of jejunum were evaluated at the age of 35 days. Based on the results, the phosphorus (P) deficiency in the diet reduced body weight (BW), average daily gain (ADG), length and strength of tibia and increased feed conversion ratio (FCR) compared to PC group. However, the supplementation of Hostazym ® or RLL probiotic into the feed improved BW, ADG, FCR, disappearance of Phytate-P and retention of P, length and strength of the tibia in a level similar to PC treatment. Phosphorus content of tibia in the chickens fed P-deficient diets containing RLL was similar to that of the tibia in the control group. Excreta phytate and total P excretion of the chickens decreased when diets contained Hostazym ® , RLL and RLL + LBS. In addition, the diet containing RLL + LBS probiotic increased villi height compared with other treatments (p < .05). Further, recombinant L. lactis could represent phytase activity in the gut environment of the chickens and could be an alternative to the commercial phytase., (© 2020 Blackwell Verlag GmbH.)

To evaluate the effects of whey protein (WP) sources on performance, liver antioxidants and immune responses of broiler chickens, 300 one-d-old male Ross 308 chickens were randomly allocated into six treatments with five replications of 10 birds each. This study was conducted on the basis of a completely randomized design in a 3 × 2 factorial arrangement with dietary supplemental WP sources (no WP; 2% WP and 2% whey protein concentrate (WPC)) and ethanol (zero and 6%) into drinking water. Birds were challenged with ethanol 6% from 10 to 24 days of age. Growth performance, immune responses, intestinal morphology and antioxidant enzymes were assessed in both challenged and non-challenged groups. There was a significant interaction between ethanol and WP sources for growth performance, so that weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) were significantly improved in broiler chickens challenged with ethanol and fed with WP (p < .05). Intestinal morphology, humoral responses and heterophil to lymphocyte ratio (H/L) were not affected by WP sources. Cellular immunity responses were significantly lower in control group and challenged birds fed with WP compared with other groups after 48 hr of phytohemagglutinin-P (PHA-P) injection. Ethanol challenge decreased liver antioxidant enzyme activities and increased levels of malondialdehyde (MDA) and alanine aminotransferase (ALT) activities. Dietary inclusion of WP and WPC increased levels of liver antioxidant enzymes and decreased MDA and ALT activities. It can be recommended to use WP for improving the growth performance and liver antioxidant enzymes in broiler chickens challenged with ethanol., (© 2020 Blackwell Verlag GmbH.)

Objectives: Zinc is an effective factor in the reproductive system. Insulin resistance (IR) is known as an important disorder in patients with polycystic ovary syndrome (PCOS). Mammalian target of rapamycin ( mTOR) , which controls key cell activities, in particular, is activated in disorders such as PCOS. The present study was conducted to observe the therapeutic effects of organic zinc on IR, mTOR gene expression, and pathogenesis of PCOS in a rat model induced-PCOS., Materials and Methods: Experimental treatments were performed on control and treated groups, consisting of healthy controls (Control, water, and standard feed intake and daily injection of sesame oil alone), Polycystic control (PCO, injection of 4 mg/kg estradiol valerate (EV) for four weeks). Treated groups (PCO-ZM 25, PCO-ZM 75, and PCO-ZM 175) after 4 weeks of receiving EV, were daily given three levels of 25, 75, and 175 mg zinc methionine/kg BW for 15 days, respectively., Results: Injection of EV dramatically increased body and ovarian weights, levels of LH, testosterone, estradiol, triglyceride, fasting insulin, fasting glucose, HOMA-IR, IGF-1, gene expression of mTOR , and number of cysts ( P <0.05). It also reduced the level of progesterone, HDL-C, and the number of antral follicles ( P <0.05). However, by increasing zinc-methionine application especially at 175 mg/kg BW, the induction effects of EV were improved on ovarian cysts ( P <0.05)., Conclusion: Organic zinc showed beneficial effects in the EV induced PCOS rats via decreased insulin resistance and mTOR expression, restored the hormonal profile, and decreased the number of cysts in the ovaries.

Probiotics are beneficial microorganisms and have long been used in food production as well as health promotion products. Bioengineered probiotics are used to express and transfer native or recombinant molecules to the mucosal surface of the digestive tract to improve feed efficiency and promote health. Lactococcus lactis is a potential probiotic candidate to produce useful biological proteins. The aim of this investigation was to develop a recombinant Lactococcus lactis with the potential of producing phytase. To enhance the efficiency of expression and secretion of recombinant phytase, usp45 signal peptide was added to the expression vector containing phytase gene (appA2) derived from Escherichia coli. Sequencing of recombinant plasmid containing appA2 showed the correct construction of plasmid. Total length of the phytase insert was 1.25 kbp. A Blast search of the cloned fragment showed 99% similarity to the reported E. coli phytase sequence in the GenBank (accession number: AM946981.2). A plasmid containing usp45 and appA2 electrotransferred into Lactococcus lactis. Zymogram with polyacrylamide gel revealed that the protein extract from the supernatant and the cell pellet of recombinant bacteria had phytase activity. Enzyme activity of 4 U/ml was obtained in cell extracts, and supernatant maximal phytase activity was 19 U/ml. The recombinant L. lactis was supplemented in broiler chicken feed and showed the increase of apparent digestibility on phytate phosphorus in the digestive tract and it was same as performance of E. coli commercial phytase.

Background: With the increasing concern for health and nutrition, dietary fat has attracted considerable attention. The composition of fatty acids in the diet is important because they are associated with major diseases including cancers, diabetes, and cardiovascular disease. The fatty acid synthase (FASN) and stearoyl-CoA desaturase (delta-9-desaturase) (SCD) genes affect fatty acid composition (1). The expression of SCD and FASN genes is related to an increase in conjugated linoleic acid (CLA) in dairy products, which benefits human health.The aim of current study was to investigate expression changes of SCD and FASN genes that resulted from crossbreeding the local Baluchi sheep with alien breeds., Methods: We collected tissue samples from the mammary glands of 24 single-born ewes from local Baluchi and synthetic Iran-Black and Arman sheep breeds in the Abbas Abad breeding center. After RNA extraction and cDNA synthesis, real-time PCR was performed with all samples in triplicate., Results: The maximum and minimum expression of SCD and FASN genes was in the local Baluchi sheep and the crossbred Arman sheep, respectively., Conclusion: With the highest SCD and FASN gene expression in local Baluchi sheep and relatively less expression of these genes in synthetic Iran-Black and Arman Sheep breeds, it may be necessary to consider the consequences of crossbreeding local sheep and the fatty acid composition of their dairy products.

Background: Stearoyl-CoA desaturase (SCD) is a key enzyme that converts saturated fatty acids (SFAs) to monounsaturated fatty acids (MUFAs) in fat biosynthesis. Despite being crucial for interpreting SCDs' roles across species, the evolutionary relationship of SCD proteins across species has yet to be elucidated. This study aims to present this evolutionary relationship based on amino acid sequences., Methods: Using Multiple Sequence Alignment (MSA) and phylogenetic construction methods, a hypothetical evolutionary relationship was generated between the stearoyl-CoA desaturase (SCD) protein sequences between 18 different species., Results: SCD protein sequences from Homo sapiens, Pan troglodytes (chimpanzee), and Pongo abelii (orangutan) have the lowest genetic distances of 0.006 of the 18 species studied. Capra hircus (goat) and Ovis aries (Sheep) had the next lowest genetic distance of 0.023. These farm animals are 99.987% identical at the amino acid level., Conclusions: The SCD proteins are conserved in these 18 species, and their evolutionary relationships are similar.