Влияние системы удобрений на количество фосфатмобилизирующих микроорганизмов в черноземе луговом

Изучали влияние системы удобрений на численность фосфатмобилизирующих микроорганизмов как компонента микробоценоза чернозема лугового. Установлено, что количество фосфатмобилизирующих микроорганизмов не коррелирует с дозой вносимых в севообороте фосфорных минеральных удобрений и степенью подвижности фосфора в почве, а определяется, предположительно, наличием углерода. Показано также, что в вариантах опыта с искусственным РК-фоном и ежегодным внесением удобрений наблюдается повышенное содержание микроорганизмов, мобилизирующих минеральные и органические фосфаты, педотрофов, целлюлолитиков, олигонитрофилов, иммобилизаторов минерального азота. В почве экстенсивного варианта наблюдается максимальное в опыте содержание иммобилизаторов минерального азота и азотобактера. Расходование органического вещества превышает его синтез на всех указанных агрофонах.Вивчали вплив системи удобрення на чисельність фосфат-мобілізувальних мікроорганізмів як компоненту мікробоценозу чорноземного лучного ґрунту. Встановлено, що кількість фосфатмобілізувальних мікроорганізмів не корелює з дозою внесених у сівозміну фосфорних мінеральних добрив і ступенем рухомості фосфору у ґрунті, а визначається, вирогідно, наявністю вуглецю. Показано також, що у варіантах досліду з штучним РК-фоном і щорічним внесенням мінеральних добрив спостерігається підвищення чисельності фосфатмобілізувальних мікроорганізмів, педотрофів, целюлозоруйнівних бактерій, олігонітрофілів, імобілізаторів мінерального азоту. У ґрунті екстенсивного варіанту спостерігається максимальний у досліді вміст імобілізаторів мінерального азоту і азотобактеру. Витрачання органічної речовини перевищує ії синтез на всіх досліджених агрофонах.The influence of the system of fertilizers on the number of phosphorus-mobilizing microorganisms as the component of microbiocenosis of meadow chernozem was studied. It was established that amount of phosphorus-mobilizing microorganisms had not correlated with phosphoric mineral fertilizer dose applied in crop rotation and degree of phosphorus mobility in soil and was determined apparently by the availability of carbon-bearing substratum. It was also shown that in variants with artificial PK-background and annual mineral fertilizer use the raised contents of phosphorus mobilizing microorganisms, pedotrophs, cellulolytic microbes, oligonitrophyls and the immobilizers of mineral nitrogen was observed. In the soil of extensive variant the content of mineral nitrogen immobilizers and azotobacter was maximized. Utilization of organic material had exceeded its syntheses in all studied agricultural backgrounds

In vitro inhibition of Eimeria tenella invasion of epithelial cells by phytochemicals

Resistance to coccidiostats and possible future restrictions on their use raise the need for alternative methods of reducing coccidiosis in poultry. The aim of this study was to evaluate the effect of selected phytochemicals on Eimeria tenella sporozoite invasion in vitro. Four phytochemicals were selected on the basis that they reduce the virulence of Eimeria spp. and/or provide immune modulatory benefits to host cells: betaine, carvacrol, curcumin and Echinacea purpurea extract (EP). Madin–Darby bovine kidney (MDBK) cells were covered by medium containing phytochemicals at the highest concentration which was non-toxic to the cells. Salinomycin 50 μg/ml was positive control; negative control was medium only. E. tenella (Houghton strain) sporozoites were added to wells and after incubation for 2, 4 or 20 h at 37 °C, cells were fixed and stained with hematoxylin–eosin. Ten evenly spaced fields per well were photographed and the percentage of cells invaded by sporozoites was calculated and normalized to the control. At 2 h, carvacrol, curcumin and EP showed a significantly lower percentage of sporozoite invasion than the untreated control; in contrast, betaine treatment represented a significantly higher invasion percentage. Combining carvacrol with EP inhibited E. tenella invasion more effectively than applying the compounds individually, but the further addition of curcumin did not reduce invasion further. In conclusion, this study shows that invasion of MDBK epithelial cells by E. tenella sporozoites is inhibited in the presence of carvacrol, curcumin, or EP and enhanced by betaine. There may be potential for developing these phytochemicals as anti-coccidial feed or water additives for poultry

Genomic markers associated with antibody response to Newcastle disease virus of Sasso chickens raised in Ethiopia

Newcastle disease virus (NDV) is one of the highly contagious avian pathogens that threatens poultry producers in endemic zones due to its epidemic potential. Selection for antibody (Ab) response can effectively improve disease resistance in chickens. However, the molecular basis of the variation in Ab response to NDV is unclear. This study aimed to detect genomic markers and genes modulating Ab response to NDV in chickens reared under tropical, outdoor conditions. A genome-wide association study (GWAS) was conducted on Sasso T451A chickens that were naturally exposed to infectious diseases from 56 to 112 days of age to identify regions associated with Ab response to NDV. Phenotypic immune data from 935 chickens, monitored in two batches, and genotyping data of these chickens based low-pass sequencing (2,676,181 single nucleotide polymorphisms, SNPs) were used. BioMart data mining and variant effect predictor tools were used to annotate SNPs and candidate genes, respectively. A total of five SNPs (rs316795557 (FOXP2), chr 1; rs313761644 (CEP170B), chr 5; rs733628728, chr 13; and two unnamed SNPs, chr 30 and chr 33) were associated with the chicken antibody response to NDV at the suggestive significance level. These SNPs are located on chromosomes 1, 5, and 13 and are in genomic regions that contain several genes with roles in the regulation of the immune response. The results of this study pave the path for more investigation into the host immune response of chickens to NDV.</p

Immunogenic Eimeria tenella Glycosylphosphatidylinositol-Anchored Surface Antigens (SAGs) Induce Inflammatory Responses in Avian Macrophages

, but the ability of these proteins to stimulate immune responses in the chicken is unknown. infection. Concomitantly, treatment with rSAGs 4, 5 and 12 suppressed the expression of IL-12 and IFN-γ and elevated that of IL-10, suggesting that during infection these molecules may specifically impair the development of cellular mediated immunity. pathogenicity associated with the endogenous second generation stages

Phenotypic characterisation of African chickens raised in semi-scavenging conditions

In sub-Saharan Africa, most poultry production is traditional with birds being raised by smallholders in free-range semi-scavenging conditions. The aim of our project is to extensively characterise phenotypes of chickens raised in typical African farming conditions, by measuring production, immunity and survival characteristics. In total, 2,573 chickens were raised in five batches in the poultry facility at ILRI in Ethiopia. These chickens were phenotypically characterised and sampled across an eight-week period. Traits measured included weekly body weight, growth rate, breast muscle weight in carcass, mortality/survival, and immunological titres. The population of chickens had extensive variance at these phenotypes. For body weight, 65% of the total phenotypic variance was attributed to the individual birds providing an excellent source of variation for identifying potential selection markers. This data will subsequently be used along with whole genome sequencing data of these birds to identify selection targets to underpin future breeding programs