Necrotic enteritis challenge regulates peroxisome proliferator-1 activated receptors signaling and β-oxidation pathways in broiler chickens

Necrotic enteritis (NE) is an important enteric disease in poultry and has become a major concern in poultry production in the post-antibiotic era. The infection with NE can damage the intestinal mucosa of the birds leading to impaired health and, thus, productivity. To gain a better understanding of how NE impacts the gut function of infected broilers, global mRNA sequencing (RNA-seq) was performed in the jejunum tissue of NE challenged and non-challenged broilers to identify the pathways and genes affected by this disease. Briefly, to induce NE, birds in the challenge group were inoculated with 1 mL of Eimeria species on day 9 followed by 1 mL of approximately 10⁸ CFU/mL of a NetB producing Clostridium perfringens on days 14 and 15. On day 16, 2 birds in each treatment were randomly selected and euthanized and the whole intestinal tract was evaluated for lesion scores. Duodenum tissue samples from one of the euthanized birds of each replicate (n = 4) was used for histology, and the jejunum tissue for RNA extraction. RNA-seq analysis was performed with an Illumina RNA HiSeq 2000 sequencer. The differentially expressed genes (DEG) were identified and functional analysis was performed in DAVID to find protein–protein interactions (PPI). At a false discovery rate threshold <0.05, a total of 377 DEG (207 upregulated and 170 downregulated) DEG were identified. Pathway enrichment analysis revealed that DEG were considerably enriched in peroxisome proliferator-activated receptors (PPAR) signaling (P < 0.01) and β-oxidation pathways (P < 0.05). The DEG were mostly related to fatty acid metabolism and degradation (cluster of differentiation 36 [CD36], acyl-CoA synthetase bubblegum family member-1 [ACSBG1], fatty acid-binding protein-1 and -2 [FABP1] and [FABP2]; and acyl-coenzyme A synthetase-1 [ACSL1]), bile acid production and transportation (acyl-CoA oxidase-2 [ACOX2], apical sodium–bile acid transporter [ASBT]) and essential genes in the immune system (interferon-, [IFN-γ], LCK proto-oncogene, Src family tyrosine kinase [LCK], zeta chain of T cell receptor associated protein kinase 70 kDa [ZAP70], and aconitate decarboxylase 1 [ACOD1]). Our data revealed that pathways related to fatty acid digestion were significantly compromised which thereby could have affected metabolic and immune responses in NE infected birds.     

Effects of Dietary Crude Protein Levels on Growth Performance,Digestion and Metabolism,and Serum Biochemical Indexes of Super Merino Lamb

The experiment aimed to find out the effects of dietary crude protein levels on growth performance, digestion and metabolism and serum biochemical indexes of Super Merino lamb after weaning.According to the dietary crude protein level, 64 Super Merino weaned lambs were divided into four groups, which the crude protein levels were 13.25%(group Ⅰ), 14.33%(group Ⅱ), 15.53%(group Ⅲ) and 16.60%(group Ⅳ), respectively.The experiment lasted for 60 days, 30 days for the early stage and 30 days for the later stage;And on the 30th and 60th day, blood samples were collected from one head sheep chosen from each replication, and at the end of the feeding test, 3 lambs were randomly selected from each experiment group for a 15 days digestion and metabolism experiment.The results showed that ADFI and ADG in the early and total trial period were significant differences(P<0.05), ADFI and ADG of group Ⅲ were higher than others.The apparent digestibility of nutrients and ME/DE were not significantly changed(P>0.05).In the detection of serum biochemical indexes, there was no significant difference in the earlier stage(P>0.05);At the end of the test, PK and CK showed significant difference between groups(P<0.05).PK presented a rising trend as the protein level improved, CK of group Ⅰ was higher than other groups.In Super Merino lamb early weaning diet, 15.53% protein level in the diet could significantly improve ADG, the apparent digestibility of nutrients, metabolic energy digestibility.At the end of the test, PK and CK were affected by dietary crude protein level significantly.     

布鲁菌赤藓醇代谢研究概况

布鲁菌感染动物后可以逃避宿主免疫系统清除而长期存在,并严重侵害动物生殖系统。赤藓醇是布鲁菌的一种优势碳源,对布鲁菌的生长具有明显促进作用。在布鲁菌基因组中已经鉴定出6个与赤藓醇代谢相关的基因,布鲁菌的赤藓醇代谢途径也基本研究清楚。缺失布鲁菌赤藓醇代谢相关基因会造成布鲁菌在多种感染模型中的生存能力不同程度的改变。论文从布鲁菌对赤藓醇的亲嗜性、赤藓醇代谢通路及转运、赤藓醇代谢的基因调控、赤藓醇对布鲁菌毒力影响等方面进行了综述。     

Effects of a high milk intake during the pre‐weaning period on nutrient metabolism and growth rate in Japanese Black cattle

This study aimed to determine the effects of feeding an increased volume of high‐fat milk during the early post‐natal life on metabolite concentrations in the blood, the expression of key genes regulating intermediary metabolism in the skeletal muscles, and the rate of growth of Japanese Black cattle. All calves were fed a high‐fat milk replacer (crude protein, 26%; crude fat, 25.5%; total dissolved nitrogen, 116%). Control calves (n = 4) were nursed with 500 g milk replacer until 3 months of age, whereas calves in the experimental group (n = 4) were nursed with 1800 g milk replacer until 3 months, and then the volume was gradually reduced until 5 months. Body weight was significantly higher in the experimental group than in the control group at 7 months. Plasma glucose concentrations were significantly lower in the experimental group. Expression of glucose‐transporter‐4 messenger RNA (mRNA) was lower, whereas that of glucose transporter 1, cluster of differentiation 36, and carnitine palmitoyltransferase‐1b mRNA was significantly higher in the Longissimus thoracis of the experimental group. Nutritional status during early post‐natal life appears to strongly influence the growth rate and glucose and lipid metabolism in Japanese Black cattle.     

Effects of butafosfan with or without cyanocobalamin on the metabolism of early lactating cows with subclinical ketosis

Fifty‐one dairy cows with subclinical ketosis were used to investigate the effects of butafosfan alone or in combination with cyanocobalamin on metabolism. Treatments included i.v. injection of 10 ml/100 kg of body weight with butafosfan (BUT) or combined cyanocobalamin with butafosfan (BUTCO) at a similar concentration as in Catosal^®. Control cows (CON) received a 0.9% saline solution. Cows were injected on days 1–3 at 22.3 ± 0.7 days post‐partum. Milk production and composition were not affected by the treatments. In plasma, CON cows had a significantly higher plasma NEFA concentration (0.59 ± 0.03 mm ) across the study period than BUTCO cows (p < 0.05; 0.42 ± 0.03 mm ), whereas the plasma NEFA concentration of BUT was intermediate (0.52 ± 0.03 mm ) but not significantly different from CON. Both BUTCO and BUT cows had lower (p < 0.05) plasma BHBA concentrations (1.02 ± 0.06 mm and 1.21 ± 0.06 mm , respectively) across the study period than CON (1.34 ± 0.06 mm ). Plasma glucose was not different between treatments, but plasma glucagon concentrations were consistently high in BUT compared to BUTCO and CON. Lowest post‐treatment glucagon levels were observed in BUTCO. Hepatic mRNA abundance of liver X receptor α, a nuclear receptor protein involved in lipid metabolism, was higher in BUTCO compared to BUT and CON (p < 0.05) on day 7. Furthermore, on day 7, the mRNA abundance of beta‐hydroxybutyrate dehydrogenase 2 was higher in BUTCO compared to BUT and CON (p < 0.01). In conclusion, injections of combined cyanocobalamin with butafosfan post‐partum in early lactation ketotic dairy cows act on lipid metabolism with effects on plasma metabolites, most likely mediated via modified activity of key factors in the liver. Results indicate that the application of butafosfan only in combination with cyanocobalamin exhibits the expected positive effects on metabolism.     

Evidence that oxidative stress is higher in replacement gilts than in multiparous sows

The recent success obtained in term of increasing the litter size of sows has not correlated with a reduction of replacement rate. There is thus an increased economic demand for gilts with optimal reproductive potential and longevity. Unfortunately, replacement gilts are known to be more susceptible to diseases and less productive than multiparous sows. Interestingly, reproductive performance, resistance to diseases and longevity could all be largely affected by oxidative stress. To investigate whether oxidative stress conditions could account for the poor longevity of gilts, three distinct groups of conventional Yorkshire × Landrace sows were formed based on their similar age and parity (gilts, second parity sows as well as fourth to fifth parity sows). All animals were slaughtered during the post‐ovulatory period, and blood as well as tissue samples were collected. Biomarkers of oxidative damage to proteins (carbonyls) and DNA (8‐OHdG) were analysed in samples. Specific mRNA expression of major antioxidants such as glutathione peroxidases 1, 3 and 4 (GPx1, GPx3, GPx4) as well as superoxide dismutases 1 and 2 (Sod1, Sod2) were monitored in liver and kidney samples by quantitative RT‐PCR. Specific enzymatic activities of both GPx and SOD were measured by spectrophotometric assays. The plasma concentration of protein carbonyls was significantly different between the three groups with the highest concentration being observed in gilts (p ≤ 0.001). The mRNA expression levels of GPx1 and GPx4 were also significantly increased in the liver of gilts when compared to multiparous sows (p ≤ 0.05). SOD2 enzymatic activity was found to be higher in the liver of gilts than multiparous sows (p ≤ 0.05). Taken together, these results indicate that replacement gilts sustain significantly higher oxidative conditions than multiparous sows. Current findings may contribute to the design of nutritional regimens that will increase the productivity of gilts by counteracting oxidative stress.     

Transient hyperammonemia due to urea cycle enzyme deficiency in Irish wolfhounds

BACKGROUND: Irish Wolfhounds frequently have a congenital portosystemic shunt, but a considerable proportion of the 6- to 8-wk-old pups has hyperammonemia in the absence of portosystemic shunting. This hyperammonemia causes no signs and is transient, normalizing at the age of 3-4 months. HYPOTHESIS: Transient hyperammonemia has a metabolic basis in Irish Wolfhounds. ANIMALS: Two related (same sire) litters of Irish Wolfhounds (17 pups) and their parents were studied. METHODS: Integrity of the portal circulation was examined by ultrasonography and scintigraphy. Absence of parenchymal liver disease was verified by liver biopsy. Amino acid profiles were measured in 4 pups and repeated in 2 of these pups when ammonia concentrations had normalized. The amino acid profiles were compared with those of healthy Irish Wolfhound pups. RESULTS: Fasting venous ammonia concentrations were high (113-622 microg/dL, 65-345 micromol/L) in all pups, whereas bile acids were within reference range in all but 1. The ammonia and bile acid concentrations from all parents were within reference range. Portosystemic shunting was excluded in all but 1 pup. Liver biopsy excluded significant lesions in all 10 pups examined. Hypercitrullinemia was found and persisted even when ammonia had normalized, at the expense of an increase in glutamine and asparagine. CONCLUSIONS AND CLINICAL IMPORTANCE: Citrulline concentrations are controlled by the urea cycle enzymes argininosuccinase and argininosuccinate synthetase, and a defect in either of these enzymes may be responsible for the transient hyperammonemia in Irish Wolfhounds. Resolution of the hyperammonemia is associated with increased activity of alternative metabolic pathways forming glutamine and asparagine. Confirmation requires measurement of enzyme activities in liver tissue.