Alginate oligosaccharides preparation,biological activities and their application in livestock and poultry

Alginate oligosaccharides(AOS), belonging to the class of functional marine oligosaccharides, are low-molecular polymers linked by β-1,4-mannuronic acid(M) and α-1,4-guluronic acid(G), which could be classically obtained by enzymatic hydrolysis of alginate. With low viscosity and good water solubility, as well as anti-oxidant, immune regulation, anti-bacterial and antiinflammatory activities, AOS have been widely used in medical science and functional food, green agriculture and other fields. As new bio-feed additives, AOS have broad potential applications in animal husbandry. In this review, the sources of alginate, chemical structure and preparation methods of AOS, and their biological activities and application in livestock and poultry are summarized. We expect this review could contribute to lay a foundation of application and further research for AOS in livestock and poultry.     

Assessing the Oxidative Stress Induced by Paracetamol Spiked in Artificial Sediment on Hyalella azteca

Paracetamol is an antipyretic analgesic widely used globally. It has been recurrently found in water bodies and is known to elicit toxic effects in aquatic species; however, its potential ability to induce oxidative stress in sentinel species remains unknown The objective was to establish a methodology to evaluate the toxicity elicited on the sentinel species Hyalella azteca by paracetamol-enriched sediment using oxidative stress tests. Concentrations used in assays were determined using the previously obtained median lethal concentration (72?h LC₅₀). The following oxidative stress biomarkers were evaluated: lipid peroxidation (LPO), protein carbonyl content (PCC) in order to determine oxidized protein content, and the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX). LPO and PCC increased significantly while SOD, CAT, and GPX decreased significantly (p?<?0.05) with respect to controls. Paracetamol induces oxidative stress on H. azteca, and the set of tests employed is helpful in evaluating the toxicity of this group of pharmaceuticals on aquatic species.     

Self-assembled pullulan-silica oxygen barrier hybrid coatings for food packaging applications

The scope of this study encompassed the evaluation of pullulan as a suitable biopolymer for the development of oxygen barrier coatings to be applied on poly(ethylene terephthalate) (PET), especially for food packaging applications. To enhance the oxygen barrier properties of the organic phase (pullulan) even at high relative humidity values, an inorganic phase (silica), obtained through in situ polymerization, was also utilized to obtain hybrid coatings via the sol-gel technique. Transmission electron microscopy (TEM) images and Fourier transform infrared (FT-IR) spectra showed that mixing the two phases yielded a three-dimensional hybrid network formed by self-assembly and mediated by the occurrence of new hydrogen-bond interactions at the intermolecular level, although the formation of new covalent bonds could not be excluded. The deposition of the hybrid coatings decreased the oxygen transmission rate (OTR) of the plastic substrate by up to 2 orders of magnitude under dry conditions. The best performance throughout the scanned humidity range (0%-80% relative humidity) was obtained for the formulation with the lowest amount of silica (that is, an organic/inorganic ratio equal to 3).     

Effects of graded levels of xylo-oligosaccharides on growth performance,serum parameters,intestinal morphology,and intestinal barrier function in weaned piglets

The objective of this study was to investigate the effects of xylo-oligosaccharides (XOSs) supplementation on growth performance, serum parameters, small intestinal morphology, intestinal mucosal integrity, and immune function in weaned piglets. A total of 240 weaned piglets with an average body weight (BW) of 8.82 ± 0.05 kg (28 d of age) were assigned randomly to four dietary treatments in a 28-d trial, including a control (CON) diet and three diets with XOS supplementation at the concentration of 100 (XOS100), 500 (XOS500), and 1,000 (XOS1000) mg/kg. There were four replicates per treatment with 15 pigs per pen. From day 1 to 14, there were no differences (P > 0.05) in average daily gain (ADG), average daily feed intake, and gain to feed ratio (G:F) during the different treatments. The different doses of XOSs showed a quadratic effect on BW on day 28, ADG, and G:F on day 1 to 28 of piglets (P < 0.05). From day 15 to 28, ADG of pigs fed the XOS500 diet was higher (P < 0.05) than pigs fed the CON diet. During the overall period (day 1 to 28), pigs fed the XOS500 diet had a higher BW, ADG, and G:F than pigs fed the CON diet (P < 0.05). In addition, compared with the CON group, the XOS500 group had significantly higher serum total antioxidant capacity, total superoxide dismutase and catalase levels, and lower malondialdehyde levels on days 14 and 28 (P < 0.05). The serum immunoglobulin G (IgG) concentration in the XOS500 group was also significantly higher compared with the CON group on days 14 and 28 (P < 0.05). However, serum immunoglobulin A and immunoglobulin M were not affected by the dietary treatments. Supplementation of XOS500 to the feed significantly increased the villus height (VH) and VH to crypt depth ratio in the jejunum and ileum in comparison with the CON and XOS1000 groups. Moreover, the XOS500 group significantly elevated the expression levels of occludin and zonula occludens protein-1 in the ileum compared with the CON group. The ileal interleukin (IL)-1β, IL-8, and interferon (IFN)-γ mRNA expression levels in the XOS100 and XOS500 groups were markedly lower than in the CON group. In contrast, the ileal IL-10 mRNA expression levels were remarkably higher in the XOS500 than in the CON group. In conclusion, XOSs have a beneficial effect on growth performance by improving serum antioxidant defense system, serum IgG, small intestinal structure, and intestinal barrier function in weaned piglets.     

Effect of Ascorbic Acid Concentrations,Methods of Cooling and Freezing on Boer Goat Semen Cryopreservation

To improve the Boer goat semen quality during cryopreservation process, three experiments were carried out to investigate the effect of (i) different concentration of ascorbic acid supplementation (ii) rate of cooling with chilled semen characteristics and (iii) method of freezing on post‐thaw Boer goat sperm using Tris‐based extender. Ascorbic acid at 8.5 mg/ml improved the sperm parameters (motility, integrity of membrane and acrosome, morphology and viability), compared to control in cooled samples (p < 0.05). With regard to other concentrations and post‐thawed parameters, ascorbic acid at 2.5–8.5 mg/ml led to higher percentages of sperm motility and integrities of membrane and acrosome when compared to control (p < 0.05). Slow cooling rises to higher percentages of sperm motility, acrosome integrity and viability, in comparison with fast cooling, in terms of cooled and frozen samples (p < 0.05). Programmable freezing method produced the higher percentages of sperm motility, integrities of membrane and acrosome and viability when compared to the freezing method of polystyrene box during goat sperm freezing (p < 0.05). In conclusion, chilled and post‐thawed sperm quality of Boer goat was improved when a Tris‐based extender supplemented with ascorbic acid was used at stages of different cooling rates and freezing methods.     

A Novel Halotolerant Bacterium Isolated from El Golea Lake in Algeria and Antimicrobial Potential of this Strain

A halotolerant, gram positive, motile and rod, was isolated from the E1 Gol6a lake of Ghardaia, Alegria and screened for its antimicrobial potential. The strain showed an inhibitory effect to gram positive and gram negative bacteria against Cladosporium spp. and a slight inhibitory effect against C. albicans using chloroform as the extraction solvent and the nutrient broth as production medium. 16S rRNA sequencing showed that the isolate named LMB3981 is a new taxon in the family of Bacillaceae （with 96% similarity）. The strain is close to Filobacillus milosensis and Bacillus haloalkaliphilum with 95% similarity. The phenotypic study showed differences between LMB3981 and two strains that are near and have confirmed the results of 16S rRNA sequencing by specific metabolic properties of the strain.     

Hereditary nasal parakeratosis in Labrador Retrievers

Hereditary nasal dermatitis is reported in 14 Labrador Retrievers and 4 Labrador Retriever crosses. This appears to be a newly described inherited disorder for which an autosomal recessive mode of inheritance is suspected. The lesions were first noted between 6 and 12 months of age. Histopathological analysis revealed parakeratotic hyperkeratosis, often with marked multifocal accumulation of proteinaceous fluid between keratinocytes within the stratum corneum and superficial stratum spinosum. There was also a sub-basal lymphoplasmacytic infiltration within the superficial dermis. Immunohistochemistry staining for IgG (n = 4), distemper and papillomaviruses (n = 4) were negative, as were serum antinuclear antibody serology (n = 4) and fungal culture (n = 7). Electron microscopy revealed an altered cornification process: retention of nuclear chromatin, absence of lamellar bodies and marked intercellular oedema. Dogs did not respond to oral administration of zinc methionin (n = 3), cephalexin (n = 4), vitamin A alcohol (n = 1) or topical tretinoin (n = 1). Improvement of the lesions was obtained with topical vitamin E (n = 2), petroleum jelly (n = 2), and propylene glycol (n = 5).     

Suppression of Rhizoctonia root-rot of tomato by Glomus mossae BEG12 and Pseudomonas fluorescens A6RI is associated with their effect on the pathogen growth and on the root morphogenesis

Rhizoctonia solani root-rot is a major soilborne disease causing growth and yield depression. The ability of Glomus mosseae BEG12 and Pseudomonas fluorescens A6RI to suppress this soilborne disease in tomato was assessed by comparing the shoot and root growth of plants infested with R. solani 1556 when protected or not by these beneficial strains. The epiphytic and parasitic growth of the pathogenic R. solani 1556 was compared in the presence and absence of the biocontrol agents by microscopical observations allowing the quantification of roots with hyphae appressed to epidermal cells (epiphytic growth) and of roots with intraradical infection (parasitic growth). The root architecture of the tomato plants under the different experimental conditions was further characterized by measuring total root length, mean root diameter, number of root tips and by calculating degree of root branching. G. mosseae BEG12 and P. fluorescens A6RI fully overcame the growth depression caused by R. solani 1556. This disease suppression was associated with a significant decrease of the epiphytic and parasitic growth of the pathogen together with an increase of root length and of the number of root tips of inoculated tomato plants. The combined effects of G. mosseae BEG12 and P. fluorescens A6RI on pathogen growth and on root morphogenesis are suggested to be involved in the efficient disease suppression.     

Fasting influences steroidogenesis, vascular endothelial growth factor (VEGF) levels and mRNAs expression for VEGF, VEGF receptor type 2 (VEGFR-2), endothelin-1 (ET-1), endothelin receptor type A (ET-A) and endothelin converting enzyme-1 (ECE-1) in newly formed pig corpora lutea

This study was designed to verify whether fasting influences vascular endothelial growth factor (VEGF) production and VEGF, VEGF receptor-2 (VEGFR-2) as well as endothelin (ET) system members (endothelin converting enzyme-1, ECE-1; ET-1; endothelin receptor type A, ET-A) mRNA expression in pig corpora lutea; furthermore, we wanted to assess whether fasting affects steroidogenesis in luteal cells. Eight prepubertal gilts were induced to ovulate and were randomly assigned to two groups: (A) n = 4, normally fed; and (B) n = 4, fasted for 72 h starting 3 days after ovulation. At the end of fasting, ovaries were removed from all the animals and corpora lutea (CLs) were collected. VEGF and steroid levels in luteal tissue were determined by ELISA and RIA, respectively; VEGF, VEGFR-2, ET-1, ET-A and ECE-1 mRNAs expression was measured by real-time PCR. VEGF protein levels were similar in the two groups, while all steroid (progesterone, testosterone, estradiol 17beta) concentrations were significantly (P < 0.001) higher in CLs collected from fasted animals compared with those from normally fed gilts. VEGF, VEGFR-2, ET-1 and ECE-1 (but not ET-A) mRNA expression was significantly lower (P < 0.05) in fasted versus normally fed animals. The overall conclusion is that all the parameters studied are affected by feed restriction, but the mechanisms activated at luteal level are possibly not fully adequate to compensate for nutrient shortage.