Effects of parity and days in milk on milk composition in correlation with ß-hydroxybutyrate in tropic dairy cows.

The current study was conducted to evaluate the effect of parity and days in milk on milk yield and milk production traits and their correlation with ß-hydroxybutyrate (BHB) concentrations in milk of Chinese tropic Holstein dairy cows which are adapted to a humid subtropical climate in central China. About 3055 milking records of Holstein cows were obtained from three farms in the hot region in the center of China. The records were classified according to parity to 4 categories: first parity, second parity, third parity, and greater than third parity. According to days in milk, there were 4 groups, first group from (1-100 days), second group from (101-200 days), third group from (201-305 days), and fourth group (>305 days). Milk samples collected between April and November 2019 from the three farms were routinely checked for milk components including BHB using mid-infrared spectroscopy a MilkoScan FT+ (Foss, Hillerød, Denmark). Data were analyzed by multivariate analysis of variance (generalized linear model, GLM). Pearson's correlation coefficients were used to measure the correlation between SCC and BHB with milk yield and milk production traits. Results showed the significant effect of parity and days in milk on milk yield and milk production traits. There was a negative effect of parity and days in milk on milk quality, with increasing parity and days in milk being associated with higher somatic cell count (SCC) (P <0.001). Days in milk significantly affected (P=0.001) BHB. It was concluded that with increasing parity and prolonged days in milk, there was a negative effect on milk quality and udder health of the tropic dairy cows in central China. Based on the results of the current study, sampling milk for specific metabolites, somatic cell count, and quality are sufficient to asses herd health.

Effect of Low-Dose Gamma Radiation and Lipoic Acid on High- Radiation-Dose Induced Rat Brain Injuries.

AIM: This work aims to investigate the possible radio-adaptive mechanisms induced by low-dose (LD) whole-body γ-irradiation alone or combined with alpha-lipoic acid (ALA) administration in modulating high-dose (HD) head irradiation-induced brain injury in rats. MATERIALS AND METHODS: Rats were irradiated with LD (.25 Gy) 24 hours prior HD (20 Gy), and subjected to ALA (100 mg/kg/day) 5 minutes after HD and continued for 10 days. At the end of the experiment, animals were sacrificed and brain samples were dissected for biochemical and histopathological examinations. RESULTS: HD irradiation-induced brain injury as manifested by elevation of oxidative stress, DNA damage, apoptotic, and inflammatory markers in brain tissue. Histological examination of brain sections showed marked alterations. However, LD alone or combined with ALA ameliorated the changes induced by HD. CONCLUSION: Under the present experimental conditions, LD whole-body irradiation exhibited neuroprotective activity against detrimental effects of a subsequent HD head irradiation. This effect might be due to the adaptive response induced by LD that activated the anti-oxidative, anti-apoptotic, and anti-inflammatory mechanisms in the affected animals making them able to cope with the subsequent high-dose exposure. However, the combined LD exposure and ALA supplementation produced a further modulating effect in the HD-irradiated rats.

Comparative Transcriptome Analysis Revealed Genes Involved in Sexual and Polyploid Growth Dimorphisms in Loach (Misgurnus anguillicaudatus).

Sexual and polyploidy size dimorphisms are widespread phenomena in fish, but the molecular mechanisms remain unclear. Loach (Misgurnus anguillicaudatus) displays both sexual and polyploid growth dimorphism phenomena, and are therefore ideal models to study these two phenomena. In this study, RNA-seq was used for the first time to explore the differentially expressed genes (DEGs) between both sexes of diploid and tetraploid loaches in four tissues (brain, gonad, liver, and muscle). Results showed that 21,003, 17, and 1 DEGs were identified in gonad, liver, and muscle tissues, respectively, between females and males in both diploids and tetraploids. Regarding the ploidy levels, 4956, 1496, 2187, and 1726 DEGs were identified in the brain, gonad, liver, and muscle tissues, respectively, between tetraploids and diploids of the same sex. When both sexual and polyploid size dimorphisms were considered simultaneously in the four tissues, only 424 DEGs were found in the gonads, indicating that these gonadal DEGs may play an important regulatory role in regulating sexual and polyploid size dimorphisms. Regardless of the sex or ploidy comparison, the significant DEGs involved in glycolysis/gluconeogenesis and oxidative phosphorylation pathways were upregulated in faster-growing individuals, while steroid hormone biosynthesis-related genes and fatty acid degradation and elongation-related genes were downregulated. This suggests that fast-growing loaches (tetraploids, females) have higher energy metabolism levels and lower steroid hormone synthesis and fatty acid degradation abilities than slow-growing loaches (diploids, males). Our findings provide an archive for future systematic research on fish sexual and polyploid dimorphisms.

Diminazene aceturate extenuate the renal deleterious consequences of angiotensin-II induced by γ-irradiation through boosting ACE2 signaling cascade.

AIM: This work aims to explore the role of diminazene aceturate (DIZE) in the enhancement of angiotensin-converting enzyme-2 (ACE2) to prevent the inflammatory and fibrotic response induced by γ-irradiation through activating the protective axis ACE2/angiotensin (1-7)/Mas receptor (ACE2/Ang(1-7)/Mas). METHODS: Male rats were injected i.p. with 15 mg/kg DIZE daily for 7 days pre and post-irradiation, where 7.5 Gy of γ-radiation as a single dose was used. KEY FINDINGS: Gamma radiation induced a significant elevation of renal biochemical parameters: urea, creatinine and blood urea nitrogen (BUN) in serum with a significant disturbance in oxidative stress markers: elevation in malondialdehyde (MDA) associated with a depletion of reduced glutathione (GSH) and superoxide dismutase (SOD). Beside elevation in the level of angiotensin II (AngII) that lead to remarkably increases in the levels of the renal inflammatory mediators: tumor necrosis factor-α (TNF-α), nuclear factor kappa B (NF-κB) and interleukin-1ß (IL-1ß) as well as renal fibrogenic markers: transforming growth factor-ß1 (TGF-ß1), connective tissue growth factor (CTGF), and hydroxyproline content in the renal tissues. DIZE caused marked expansion in the expression of ACE2 consequently decreased the expression of AngII and increased the expression of Ang(1-7) which through its Mas receptor ameliorates the biochemical and histopathological damage induced by radiation. SIGNIFICANCE: DIZE-induced stimulation of ACE2 subdues the renal deleterious consequences induced by γ-radiation via activation of ACE2/Ang(1-7)/Mas axis in rats.