Ambient ammonia does not appear to inhibit the immune response to infectious bronchitis virus vaccination and protection from homologous challenge in broiler chickens

Effects of tannic acid supplementation on growth performance, gut health, and meat production and quality of broiler chickens raised in floor pens for 42 days

A study was conducted to investigate the effects of tannic acid (TA) supplementation on growth performance, gut health, antioxidant capacity, gut microbiota, and meat yield and quality in broilers raised for 42 days. A total of 700 one-day-old male broiler chickens (Cobb500) were allocated into 5 treatments with 7 replicates of 20 birds per pen. There were five treatments: 1) tannic acid 0 (TA0: basal diet without TA); 2) tannic acid 0.25 (TA0.25: basal diet+0.25 g/kg TA); 3) tannic acid 0.5 (TA0.5: basal diet+0.5 g/kg TA); 4) tannic acid 1 (TA1: basal diet+1 g/kg TA); and 5) tannic acid 2 (TA2: basal diet+2 g/kg TA). The dietary phases included starter (D 0 to 18; crumble feed), grower (D 18 to 28; pellet feed), and finisher (D 28 to 42; pellet feed). On D 18, the supplementation of TA linearly reduced body weight (BW) and average daily feed intake (ADFI) (p < 0.05), and on D 28, the supplementation of TA linearly reduced BW, average daily gain (ADG), and feed conversion ratio (FCR) (p < 0.05). Relative mRNA expression of genes related to mucin production (MUC2), tight junction proteins (CLDN2 and JAM2), and nutrient transporters (B0AT1 and SGLT1) was linearly increased by the supplementation of TA (p < 0.05). The supplementation of TA tended to linearly increase the relative abundance of the family Enterobacteriaceae (p = 0.08) and quadratically increased the relative abundance of the families Lachnospiraceae and Ruminococcaceae in the cecal microbial communities (p < 0.05). On D 36, the ratio of the phyla Firmicutes and Bacteroidetes was quadratically reduced by the supplementation of TA (p < 0.05). On D 42, bone mineral density and the lean to fat ratio were linearly decreased by the supplementation of TA (p < 0.05). On D 43, total chilled carcass weight was linearly reduced (p < 0.05), and proportion of leg weight was increased by supplementation of TA (p < 0.05). The supplementation of TA linearly reduced pH of the breast meat (p < 0.05) and linearly increased redness (a*) (p < 0.05). Although the supplementation of TA positively influenced gut health and gut microbiota in the starter/grower phases, it negatively affected overall growth performance, bone health, and meat production in broilers on D 42.

Development, optimization, and validation of a method for detection of cartap, thiocyclam, thiosultap-monosodium, and thiosultap-disodium residues in plant foods by GC-ECD

A method was developed for the simultaneous determination of four nereistoxin-related pesticides, viz. cartap, thiocyclam, thiosultap-monosodium, and thiosultap-disodium, in 20 plant foods. The samples were extracted using a hydrochloric acid solution containing cysteine hydrochloride, derivatized to nereistoxin under alkaline conditions, and analyzed by gas chromatography with electron capture detector. The average recoveries of the method were 72-108%, with relative standard deviations (RSDs) of 0.3-14.7% (n = 1200, p < 0.05). The intermediate precision and reproducibility experiments using established methods were also carried out. All the results passed the Cochrane and Grubbs tests (n = 2400, p < 0.05). The RSDs of intermediate precision and RSDs of reproducibility among laboratories were in the ranges 1.7-10.9% and 2.4-15.3% (n = 2400, p < 0.05), respectively, indicating that the accuracy and precision of the method are satisfactory. This method can be used to detect nereistoxin-related pesticides in plant foods.

Transcriptome study underling difference of milk yield during peak lactation of Kazakh horse

This study was designed to provide a basis for further understanding of the mechanism of lactation based on mRNA expression differences in milk fat between different milk yields in Kazakh horses. Total RNA was extracted from the milk fat during the peak of lactation period. A total of 310 differentially expressed genes (DEGs) were identified by comparative transcriptome analysis of the high-yield and low-yield group. These DEGs regulate lactation by participated in AMPK signaling pathway, FoxO signaling pathway, ErbB signaling pathway, VEGF signaling pathway. In addition, we performed quantitative PCR to validated 5 selected DEGs and the results were in agreement with RNA-seq analysis. A new profile has been established for revealing the mechanism of equid's mammalian lactation.

The inflammatory injury of heart caused by ammonia is realized by oxidative stress and abnormal energy metabolism activating inflammatory pathway

Inflammation is an essential biological process for maintaining homeostasis in the body. However, excessive inflammatory response is closely related to many chronic diseases. Ammonia is a known environmental pollutant and a main harmful gas in the environment of livestock house. It causes deterioration of air quality and poses a threat to human and animal health. Chickens are very sensitive to ammonia. In order to assess the toxicity of ammonia to the heart, the pathology, ATPase activities, markers of oxidative stress, inflammatory pathways and inflammation markers were investigated in the hearts of chickens exposed to ammonia. The results showed that the cardiac pathological structure, oxidative stress index, and ATPase activity changed significantly in ammonia-treated chickens. In addition, the inflammation pathways (JAK/STAT and MAPK) were activated in the ammonia group, and the inflammatory markers (COX-2, TNF-α, NF-κB and PPAR-γ) were significantly altered at both mRNA and protein levels. In conclusion, excess ammonia can activate inflammatory pathways through oxidative stress and abnormal energy metabolism, and induce cardiac inflammatory injury. Our findings will provide a new insight for better assessing the toxicity mechanism of ammonia on the heart.

Ocular exposure to infectious laryngotracheitis virus alters leukocyte subsets in the head-associated lymphoid tissues and trachea of 6-week-old White Leghorn chickens

Infectious laryngotracheitis virus (ILTV), an alphaherpesvirus, causes acute respiratory disease primarily infecting the upper respiratory tract and conjunctiva. Administration of live attenuated ILTV vaccines via eye drop, drinking water, or by coarse spray elicits protective mucosal immunity in the head-associated lymphoid tissues (HALT), of which conjunctiva-associated lymphoid tissue (CALT) and the Harderian gland (HG) are important tissue components. The trachea, a non-lymphoid tissue, also receives significant influx of inflammatory cells that dictate the outcome of ILTV infection. The objective of this study was to evaluate leukocyte cellular and phenotypic changes in the CALT, HG and trachea following ocular infection with a virulent ILTV strain. At 1, 3, 5, 7 and 9 days post-infection, CALT, HG, and trachea of 6-week-old specific pathogen free (SPF) chickens ocularly-exposed to vehicle or virulent ILTV strain 63140 were dissociated, the cells enumerated and then phenotyped using flow cytometry. The CALT had the highest viral genomic load, which peaked on day 3. In ILTV-infected birds, the CALT had a decreased percentage of leukocytes. This was reflected by decreased numbers of MHCI⁺MHCII^-, MHCI⁺MHCII^low+, and CD4⁺ cells, while IgM⁺ and MHCI⁺MHCII^High+ expressing cell populations increased. In the HG, the most notable change in cells from ILTV-infected birds was a decrease in IgM expressing cells and histologically, an increase in Mott cells. In summary, an acute, ocular exposure to ILTV strain 63140 in young birds shifts subsets of lymphocyte populations in the CALT and HG with minimal impact on the trachea.