Vitamin E and beta-carotene status of dairy cows: a survey of plasma levels and supplementation practices.

Culling rate in dairy cattle has increased considerably, thereby reducing cows longevity and raising sustainability concerns worldwide. In the last decades, feeding systems have changed towards larger inclusion of preserved forages and reduced fresh herbage, which may limit vitamin E and beta-carotene dietary supply to dairy cows. Because of higher oxidative stress, engendered by greater milk production of modern genetics, the requirement for these nutrients is increased. Therefore, this study aimed to assess the current status of vitamin E and beta-carotene of commercial dairy cows. Blood vitamin E and beta-carotene concentrations were measured in 2 467 dairy cows from 127 farms in Belgium, Germany, Iberia and The Netherlands, that were visited once. Five cows were randomly selected per lactation stage per farm: Dry (between 30 and 1 day(s) before calving), Very-early (from calving until 15 days in milk (DIM)), Early (between 16 and 119 DIM), and Mid-late (from 120 DIM onwards). In addition, a survey was conducted to retrieve data on vitamin E and beta-carotene supplementation and feeding practices. Vitamin E and beta-carotene blood concentrations dropped considerably around calving. Among all surveyed cows, more than 75 and 44% were deficient in vitamin E and beta-carotene (i.e., blood concentration below 3.0 and 3.5 mg/l, respectively). Of the Very-early group, more than 97 and 78% of the cows were deficient in vitamin E and beta-carotene, respectively, with respective blood concentrations of 1.15 and 2.71 mg/l, which was significantly lower than the other lactation stages. Vitamin E and beta-carotene blood concentrations, as well as their supplementation levels, significantly varied among countries. Vitamin E and beta-carotene blood concentrations were positively related to the total estimated daily intakes of vitamin E and beta-carotene. Therefore, blood concentrations of vitamin E and beta-carotene depend on their respective level of intake, which is generally below recommendations and varies greatly between countries. Supplementation could contribute to provide cows with adequate amounts of vitamin E and beta-carotene all along the lactation, to ensure their lifetime performance and improve their fertility.

Transient inflammatory-like state and microbial dysbiosis are pivotal in establishment of mucosal homeostasis during colonisation of germ-free mice.

The gut microbiota is increasingly recognised as a key-player in defining the health status of the gastrointestinal tract. Recently, we demonstrated that colonisation of healthy germfree mice with a conventional microbiota (conventionalisation) elicits temporal and region specific host-microbe communication responses that lead to the establishment of a microbiota-accommodating homeostatic state within 30 days. Here, the microbiota composition profiles, mucosal transcriptomes and plasma-analytes in germ-free and conventionalised C57/BL 6 J mice were assessed to decipher the features of the distinctive and pivotal events occurring four days after initiation of the conventionalisation process. The dominance of the microbial genera Helicobacter, Sphingomonas and Mucispirillum in the gut microbiota coincided with the transient mounting of proinflammatory responses in the mucosa and the transiently elevated levels of specific (inflammatory) cytokines and amines in plasma. The overrepresented microbes have previously been associated with the potential to cause disease under certain conditions, illustrating that conventionalisation proceeds through a transient state that resembles situations associated with dysbiosis. However, no overt mucosal inflammation was observed, suggesting a pivotal role of the overrepresented bacterial groups in priming and maturation of the immune system during the process of conventionalisation. These findings imply that the transiently elevated relative overgrowth of particular microbial genera functions as pivotal adjuvants to elicit the corresponding proinflammatory cascades, which precede the full maturation of the different arms of the immune system following these events and is required to achieve a microbiota-accommodating homeostasis in healthy animals.

Nutrition, metabolism, and fertility in dairy cows: 3. Amino acids and ovarian function.

Plasma insulin concentrations influence resumption of ovarian activity in postpartum dairy cows, and plasma insulin can be manipulated by changing dietary starch and fat supply. The objective of this experiment was to investigate the role of dietary amino acids in altering peripheral metabolic hormones and ovarian function. Thirty-two cows were fed a standard diet from calving until 40 d in milk (DIM), and then 8 cows were transferred to each of 4 dietary treatments until 70 DIM. The 4 diets were designed to supply either low (diets 1 and 2) or high (diets 3 and 4) levels of metabolizable protein (MP), containing either low (diet 1 and 3) or high (diets 2 and 4) proportions of Leu. Leucine was manipulated with heat-treated lupins and corn gluten meal. Estrus was synchronized at 60 DIM. Between 60 and 70 DIM, energy intake and energy balance were similar among diet groups, although cows receiving high MP containing high Leu had a greater milk yield than other groups (means: 37.8, 37.1, 37.4, 39.4 +/- standard error 0.85 kg/d for diets 1 to 4, respectively). Interactions between MP and Leu were found for insulin, glucagon, and the ratio between them. Insulin was not affected by Leu in diets with low MP but was decreased by greater Leu in diets with high MP (means: 0.37, 0.32, 0.46, 0.39 +/- SE 0.031 ng/mL for diets 1 to 4, respectively). Glucagon was not affected by MP in diets with low Leu but was increased by greater MP in diets with high Leu (means: 92, 81, 88, 95 +/- SE 6.0 pg/mL for diets 1 to 4, respectively). For the low-MP treatments, the insulin-to-glucagon ratio was greater with high Leu; for the high-MP treatments, the insulin-to-glucagon ratio was greater with low Leu (means: 4.28, 5.42, 5.16, 4.22 +/- SE 0.456 for diets 1 to 4, respectively). There was no effect of MP or Leu on ovarian follicle numbers or reproductive hormones. Based on hormonal and ovarian responses, we conclude that altering metabolic hormones through manipulation of amino acid supply and balance is unlikely to have a significant effect on ovarian function in dairy cows.

Insulin and dexamethasone regulate stearoyl-CoA desaturase mRNA levels and fatty acid synthesis in ovine adipose tissue explants.

Sheep adipose tissue explants were maintained in culture for 24 h in the presence of insulin, dexamethasone, or insulin and dexamethasone, and stearoyl-CoA desaturase (SCD) messenger RNA (mRNA) levels and fatty acid synthesis were measured. Insulin increased SCD mRNA levels (P = 0.008) and synthesis of both saturated (P = 0.07) and unsaturated (P < 0.001) fatty acids but had the greatest effect on unsaturated fatty acid synthesis, resulting in the overall production of a greater (P < 0.001) proportion of monounsaturated fat. Dexamethasone, alone, had the opposite effect but actually potentiated the effect of insulin in stimulating SCD expression and both saturated and monounsaturated fatty acid synthesis, without affecting the relative proportions of each. Across adipose tissue depots, the effect of hormones was similar, although the increase in SCD mRNA levels (P = 0.008) and monounsaturated fatty acid synthesis (P < 0.001) was greater in subcutaneous adipose tissue than in the internal (omental and perirenal) depots. These data clearly show that, in ovine adipose tissue, changes in SCD gene expression in response to insulin and dexamethasone are associated with changes in monounsaturated fatty acid synthesis and suggest that it may be possible to develop strategies to manipulate sheep tissues to produce a less-saturated fatty acid profile.

Ovine adipose tissue monounsaturated fat content is correlated to depot-specific expression of the stearoyl-CoA desaturase gene.

The basis for the variation in fatty acid composition in different ovine adipose tissue depots was investigated. The proportion of stearic (C18:0) and oleic (C18:1) acids vary in a site-specific fashion; abdominal depots (omental and perirenal) contain relatively more C18:0 than C18:1, and carcass depots, especially sternum, have a markedly higher proportion of C18:1. Additionally, expression of a number of lipogenic enzyme genes (stearoyl-CoA desaturase [SCD], acetyl-CoA carboxylase-alpha [ACC-alpha], lipoprotein lipase [LPL]) and the cytoskeletal protein gene alpha-tubulin vary among depots, although the pattern of variation differs for each mRNA. When these expression data were related to the mean cell volume of adipocytes pooled from all depots, a significant pattern emerged: expression of the ACC-alpha, LPL, and alpha-tubulin genes was highly correlated with the size of adipocytes. In contrast, when the expression of SCD mRNA was assessed as a function of mean cell volume, two populations of adipocytes emerged: no significant correlation was found between the expression of SCD mRNA per adipocyte and mean cell volume for the abdominal depots, although a highly significant correlation was observed between SCD gene expression and mean cell volume for the carcass and epicardial depots. Similarly, a highly significant correlation was found for the amount of C18:1 per adipocyte and the abundance of SCD mRNA per adipocyte for the carcass and epicardial depots, whereas no significant correlation was observed for these traits for the omental and perirenal depots. Thus, the SCD gene seems to be regulated in a depot-specific fashion and in a manner distinct from that of the ACC and LPL genes.

Stearoyl-CoA desaturase mRNA is transcribed from a single gene in the ovine genome.

Clones corresponding to ovine stearoyl-CoA desaturase (SCD) cDNA were isolated from an adipose tissue cDNA library. All of these clones represented a single mRNA species as judged by restriction fragment and DNA sequence analysis. RNase protection analysis demonstrated that this SCD transcript is highly expressed in adipose tissue and liver, and in the mammary gland of lactating animals. A lower level of expression was detectable in a variety of other tissues including brain. Levels of the SCD transcript were decreased in adipose tissue during lactation, and this appears to be related to a marked decline in serum insulin and insulin-responsiveness of the tissue. Southern analysis of ovine and mouse genomic DNA demonstrated that the ovine SCD cDNA hybridised in a manner consistent with a single gene for SCD in ovine DNA; mouse genomic DNA produced a pattern of hybridisation consistent with the previously characterised mouse SCD-1 and SCD-2 genes. Three ovine cosmids were isolated that comprised the restriction fragments predicted by the genomic Southern analysis. The ovine SCD gene was predicted to be encompassed within a 23 kbp region that was present in all three cosmids. These results demonstrate that SCD is transcribed from a single gene in the ovine genome and this gene is insulin-responsive in ovine adipose tissue.

A closer look at case management.

Healthcare organizations throughout the United States are attempting to find solutions to spiraling healthcare costs. Hospital administrators are questioning the cost-effectiveness of their care delivery models, while healthcare professionals are developing innovative measures to increase the cost-effective use of resources. This article explores hospital-based case management measures that are being used not only to control costs but also to de-escalate the continuously accelerating cost increases.

Designing a curriculum for healthy work: reflections on the United Automobile, Aerospace and Agricultural Implement Workers-General Motors Ergonomics Pilot Project.

An ambitious ergonomics pilot project sponsored by UAW-GM sought to bypass traditional "top-down" methods of ergonomics training in favor of an in-house "bottom-up" approach that empowered workers to implement basic ergonomic improvements in their own work areas. UAW and GM eventually used the program as the model for a corporate-wide ergonomics program that they later implemented.