Effect of different degraded protein balances (OEB) on the performance of beef bulls and on digestibility and rumen fermentation in sheep

A total of 125 non-double-muscled Belgian Blue finishing bulls (liveweight range 375-620 kg) were used to investigate the effect of different levels of degraded protein balance in the rumen (OEB) -2, -7, -16 and -22 g/kg DM on animal performance, with the dietary content of true protein digested in the small intestine (DVE) fixed at 80 g/kg. Lower OEB levels significantly reduced daily liveweight gain from 1.57 to 1.39 kg during the first 84 days of the experiment, but not during the subsequent part. For the whole experiment, daily liveweight gain decreased from 1.40 to 1.32 kg but the difference was not significant. Intake of DM, DVE and NE for finishing was not modified by OEB level, while CP intake was reduced and OEB deficit was increased. An OEB level of -22 g/kg DM resulted in a significantly unfavourable conversion of DM and NE during the initial months (11.3 and 11.5% compared with OEB = -2 g/kg DM, respectively). For the total period the conversion of DM and NE was still less favourable, but the differences were not significant. There was a nominal decrease in cold carcass weight and dressing percentage when OEB level decreased, but the effect was not significant. The effect of different OEB levels on digestibility and rumen fermentation was investigated in a separate experiment with wethers. Apparent protein digestibility was reduced from 74.2 to 68.9% when OEB level decreased. Rumen pH and concentrations and molar percentages of volatile fatty acids were not altered by OEB level. Ammonia concentration was only reduced by a lower OEB level at 7 h after feeding. Because of a nominal reduction in daily liveweight gain, feed efficiency, carcass weight, dressing percentage and carcass conformation with decreasing OEB level, it is advisable not to feed less than -16 g OEB/kg DM in diets with 80 g DVE/kg DM to Belgian Blue non-double-muscled finishing bulls from 375 kg onwards. This tolerable OEB deficit is larger than proposed to avoid protein overfeeding

Effect of β-hydroxybutyric acid, parity, and body condition score on phenotype and proliferative capacity of colostral mononuclear leukocytes of high-yielding dairy cows

In neonatal calves, the ingestion of colostrum is imperative for preventing infectious diseases. Investigations into the transfer of passive immunity of cattle have primarily focused on the importance of colostral immunoglobulins, with a recent increase in focus on understanding the role of colostral leukocytes. The main objective of the present study was to measure the influence of parity, body condition score, serum nonesterified fatty acids, and serum beta-hydroxybutyrate concentrations of periparturient cows on phenotype and mitogen-and antigen-induced proliferative capacity of bovine colostral leukocytes. Holstein-Friesian cows (n = 141) were intramuscularly vaccinated at 60 and 30 d before the expected parturition date with a tetanus toxoid vaccine. Of these 141 animals, 28 primiparous and 72 multiparous cows were sampled immediately. after parturition. Colostrum mononuclear cell populations were identified by flow cytometry using bovine cluster of differentiation markers, and the proliferative capacity of these cells was determined using a H-3-thymidine proliferation assay. Under-conditioned cows had a significantly higher percentage of colostral macrophages than normal-conditioned animals, whereas over-conditioned cows had significantly more colostral B-lymphocytes. Serum beta-hydroxybutyrate was significantly associated with higher numbers of colostral T-lymphocytes and macrophages. Heifers had significantly higher mitogen- and antigen-induced proliferation of their colostral leukocytes than third parity or older cows. In conclusion, body condition score, parity, and serum beta-hydroxybutyrate concentration of periparturient high-yielding dairy cows were shown to influence the number of colostral macrophages or the mitogen-and antigen-induced proliferation of colostral leukocytes, possibly influencing the cellular immunity of the newborn calf

Relationships between odd- and branched-chain fatty acid profiles in milk and calculated enteric methane proportion for lactating dairy cattle

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Cow responses and evolution of the rumen bacterial and methanogen community following a complete rumen content transfer

Understanding the rumen microbial ecosystem requires the identification of factors that influence the community structure, such as nutrition, physiological condition of the host and host-microbiome interactions. The objective of the current study was to describe the rumen microbial communities before, during and after a complete rumen content transfer. The rumen contents of one donor cow were removed completely and used as inoculum for the emptied rumen of the donor itself and three acceptor cows under identical physiological and nutritional conditions. Temporal changes in microbiome composition and rumen function were analysed for each of four cows over a period of 6 weeks. Shortly after transfer, the cows showed different responses to perturbation of their rumen content. Feed intake depression in the first 2 weeks after transfer resulted in short-term changes in milk production, methane emission, fatty acid composition and rumen bacterial community composition. These effects were more pronounced in two cows, whose microbiome composition showed reduced diversity. The fermentation metrics and microbiome diversity of the other two cows were not affected. Their rumen bacterial community initially resembled the composition of the donor but evolved to a new community profile that resembled neither the donor nor their original composition. Descriptive data presented in the current paper show that the rumen bacterial community composition can quickly recover from a reduction in microbiome diversity after a severe perturbation. In contrast to the bacteria, methanogenic communities were more stable over time and unaffected by stress or host effects

Synthesis and Biological Activities of a 3′-Azido Analogue of Doxorubicin Against Drug-Resistant Cancer Cells

Doxorubicin (DOX), an anthracycline antibiotic, is one of the most active anticancer chemotherapeutic agents. The clinical use of DOX, however, is limited by the dose-dependant P-glycoprotein (P-gp)-mediated resistance. Herein, a 3′-azido analogue of DOX (ADOX) was prepared from daunorubicin (DNR). ADOX exhibited potent antitumor activities in drug-sensitive (MCF-7 and K562) and drug-resistant cell lines (MCF-7/DNR, K562/DOX), respectively. The drug resistance index (DRI) values of ADOX were much lower than that of DOX. The cytotoxicity experiments of ADOX or DOX against K562/DOX, with or without P-gp inhibitor, indicated that ADOX circumvents resistance by abolishing the P-gp recognition. This conclusion was further supported by drug influx/efflux flow cytometry experiments, as well as by molecular docking of ADOX to P-gp. In vivo animal tests, ADOX exhibited higher activity and less toxicity than DOX. The current data warranted ADOX for additional pre-clinical evaluations for new drug development

Real-time ultrasound (RTU) imaging methods for quality control of meats

In this chapter the use of real-time ultrasonography to predict in vivo carcass composition and meat traits will be reviewed. The chapter begins by discussing background and principles of ultrasound. Then aspects affecting the suitability of realtime ultrasonography and image analysis for predicting carcass composition and meat traits of meat producing species and fish will be presented. This chapter also provides an overview of the present and future trends in the application of real-time ultrasonography in the meat industry. © 2012 Woodhead Publishing Limited All rights reserved.info:eu-repo/semantics/publishedVersio