Comparison of ruminal lipid metabolism in dairy cows and goats fed diets supplemented with starch, plant oil, or fish oil

Direct comparison of cow and goat performance and milk fatty acid responses to diets known to induce milk fat depression (MFD) in the bovine reveals relevant species-by-diet interactions in ruminal lipid metabolism. Thus, this study was conducted to infer potential mechanisms responsible for differences in the rumen microbial biohydrogenation (BH) due to diet and ruminant species. To meet this objective, 12 cows and 15 goats were fed a basal diet (control), a similar diet supplemented with 2.2% fish oil (FO), or a diet containing 5.3% sunflower oil and additional starch (+38%; SOS) according to a 3 × 3 Latin square design with 25-d experimental periods. On the last day of each period, fatty acid composition (by gas chromatography) and bacterial community (by terminal-RFLP), as well as fermentation characteristics, were measured in rumen fluid samples. Results showed significant differences in the response of cows and goats to dietary treatments, although variations in some fermentation parameters (e.g., decreases in the acetate-to-propionate ratio due to FO or SOS) were similar in both species. Main alterations in ruminal BH pathways potentially responsible for MFD on the SOS diet (i.e., the shift from trans-11 to trans-10 18:1 and related increases in trans-10,cis-12 18:2) tended to be more pronounced in cows, which is consistent with an associated MFD only in this species. However, changes linked to FO-induced MFD (e.g., decreases in 18:0 and increases in total trans-18:1) were stronger in caprine rumen fluid, which may explain their unexpected susceptibility (although less marked than in bovine) to the negative effect of FO on milk fat content. Altogether, these results suggest that distinct ruminal mechanisms lead to each type of diet-induced MFD and confirm a pronounced interaction with species. With regard to microbiota, differences between cows and goats in the composition of the rumen bacterial community might be behind the disparity in the microorganisms affected by the experimental diets (e.g., Ruminococcaceae, Lachnospiraceae, and Succinivibrionaceae in the bovine, and Pseudobutryrivibrio, Clostridium cluster IV, Prevotella, and Veillonellaceae in the caprine), which hindered the assignation of bacterial populations to particular BH steps or pathways. Furthermore, most relevant variations in microbial groups corresponded to as yet uncultured bacteria and suggest that these microorganisms may play a predominant role in the ruminal lipid metabolism in both cows and goats.

Comparison of the nutritional regulation of milk fat secretion and composition in cows and goats

A study with 2 ruminant species (goats and cows) with inherent differences in lipid metabolism was performed to test the hypothesis that milk fat depression (MFD) due to marine lipid supplements or diets containing high amounts of starch and plant oil is caused by different mechanisms and that each ruminant species responds differently. Cows and goats were allocated to 1 of 3 groups (4 cows and 5 goats per group) and fed diets containing no additional oil (control) or supplemented with fish oil (FO) or sunflower oil and wheat starch (SOS) according to a 3 × 3 Latin square design with 26-d experimental periods. In cows, milk fat content was lowered by FO and SOS (-31%), whereas only FO decreased milk fat content in goats (-21%) compared with the control. Furthermore, FO and SOS decreased milk fat yield in cows, but not in goats. In both species, FO and SOS decreased the secretion of <C16 and C16 fatty acids (FA), and FO lowered >C16 FA output. However, SOS increased milk secretion of >C16 FA in goats. Compared with the control, SOS resulted in similar increases in milk trans-10,cis-12 conjugated linoleic acid (CLA) in both species, but caused a 2-fold larger increase in trans-10 18:1 concentration in cows than for goats. Relative to the control, responses to FO in both species were characterized by a marked decrease in milk concentration of 18:0 (-74%) and cis-9 18:1 (-62%), together with a ~5-fold increase in total trans 18:1, but the proportionate changes in trans-10 18:1 were lower for goats. Direct comparison of animal performance and milk FA responses to FO and SOS treatments demonstrated interspecies differences in mammary lipogenesis, suggesting a lower sensitivity to the inhibitory effects of trans-10,cis-12 CLA in goats and that ruminal biohydrogenation pathways are more stable and less prone to diet-induced shifts toward the formation of trans-10-containing intermediates in goats compared with cows. Even though a direct cause and effect could not be established, results suggest that regulation of milk fat synthesis during FO-induced MFD may be related to a shortage of 18:0 for endogenous mammary cis-9 18:1 synthesis, increase in the incorporation of trans FA in milk triacylglycerols, and limitations in the synthesis of FA de novo to maintain milk fat melting point. However, the possible contribution of biohydrogenation intermediates with putative antilipogenic effects in the mammary gland, including trans-9,cis-11 CLA, trans-10 18:1, or cis-11 18:1 to FO-induced MFD cannot be excluded.

Impact of advice given to travelers concerning the main infectious risks associated with traveling in the tropics

INTRODUCTION

The prevention of sanitary risks related to traveling in the tropics implies delivering a large amount of information to travelers. The objective of our study was to assess the knowledge acquired by travelers during a pre-travel consultation.

METHODS

A before and after study was conducted among 202 travelers having consulted at the Tours international vaccine center. We used self-administrated questionnaires (score out of 100 marks) concerning diet, hygiene, anti-vectorial prevention (AVP), and sexual-transmitted infections (STI). The scores obtained before and after consultation were compared globally and for each topic.

RESULTS

The travelers' global knowledge had improved after consultation (66.1 vs. 75.5%; P < 0.0001) as well as for each topic. The most important improvement concerned hygiene (+12.5%; P < 0.0001) and the lowest concerned STI (+5.8%; P < 0.0001). The multivariate analysis revealed that not having searched for information before consulting was the main factor associated with global knowledge improvement (P < 0.0001) (unplanned professional traveling compared to humanitarian mission prepared ahead of departure time). The recommendations for diet were less well acquired in travelers > 50 years of age than in those < 30 years of age (P < 0.002).

CONCLUSION

A specialized pre-travel consultation improves the travelers' knowledge for the main prevention measures but does not allow them to acquire all required knowledge. Taking into account the travelers' initial knowledge and their ability to learn could improve the impact of the pre-travel consultation.

Rapid HIV test in family practice

BACKGROUND

The 2010-2014 HIV/AIDS French program recommends using HIV rapid diagnostic tests in family practice. Our aim was to assess the acceptability and feasibility of the RDT in family practice in France.

METHODS

The first part of this study was to determine the opinions of family practitioners (FPs) concerning the news guidelines for screening and the possible use of rapid HIV tests in their practice. The second part was a feasibility study of the actual use of rapid HIV tests given to FPs during six months. The third part was a qualitative analysis of experience feedback to determine the impediments to using rapid HIV tests.

RESULTS

Seventy-seven percent of the 352 FPs interviewed were favorable to rapid HIV tests use. The three main impediments were: misinterpretation of test result, complexity of quality control, and lack of training: 23 of the 112 FPs having volunteered to evaluate the rapid HIV tests followed the required training session. Sixty-nine tests were handed out, and three rapid HIV tests were used; the qualitative study involved 12 FPs. The participants all agreed on the difficult use of rapid HIV tests in daily practice. The main reasons were: too few opportunities or requests for use, complex handling, difficulties in proposing the test, fear of having to announce seropositivity, significantly longer consultation.

CONCLUSION

Although FPs are generally favorable to rapid HIV tests use in daily practice, the feasibility and contribution of rapid HIV tests are limited in family practice.

Modification of a commercial DNA extraction kit for safe and rapid recovery of DNA and RNA simultaneously from soil, without the use of harmful solvents

An optimized method, based on the coupling of two commercial kits, is described for the extraction of soil nucleic acids, with simultaneous extraction and purification of DNA and RNA following a cascade scheme and avoiding the use of harmful solvents. The protocol canmonitor the variations in the recovery yield of DNA and RNA from soils of various types.The quantitative version of the protocol was obtained by testing the starting soil quantity, the grinding parameters and the final elution volumes, in order to avoid saturation of both kits.

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A first soil-crushing step in liquid nitrogen could be added for the assessment of fungal parameters.

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The protocol was efficienton different tropical soils, including Andosol, while their high contents of clays, including poorly crystalline clays, and Fe and Al oxides usually make the nucleic acid extraction more difficult.

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The RNA recovery yield from the previous tropical soils appeared to correlate better to soil respiration than DNA, which is positively influenced by soil clay content.

Migrability of PVC plasticizers from medical devices into a simulant of infused solutions

Medical devices (MD) for infusion and artificial nutrition are essentially made of plasticized PVC. The plasticizers in the PVC matrix can leach out into the infused solutions and may enter into contact with the patients. In order to assess the risk of patient exposure to these plasticizers we evaluated the migration performance of DEHP, DEHT, DINCH, and TOTM using a model adapted to the clinical use of the MDs. Each PVC tubing sample was immersed in a simulant consisting of a mixture of ethanol/water (50/50v/v) at 40°C and migration tests were carried out after 24h, 72h, and 10 days.DEHP had the highest migration ability, which increased over time. The amount of TOTM released was more than 20 times less than that of DEHP, which makes it an interesting alternative. DEHT is also promising, with a migration level three times smaller than DEHP. However, the migration ability of DINCH was similar to DEHP, with the released amounts equaling 1/8th of the initial amount in the tubing after 24h of contact. Taking into account the available toxicological data, TOTM and DEHT appear to be of particular interest. However, these data should be supplemented and correlated with clinical and toxicological studies on plasticizers and their metabolites.

Hospital and ambulatory management, and compliance to treatment in HIV infection: regional health insurance agency analysis

OBJECTIVE

We had for objective to study HIV management (hospital, ambulatory, and mixed) and assess compliance with health insurance database.

METHOD

We conducted a retrospective study using the French Social Security (CPAM) database. The inclusion criteria were: age>18years of age, at least 2 prescriptions of antiretroviral therapy.

RESULTS

Five hundred and seventy-five patients were included: extra-hospital (12), hospital (162), mixed (401). The prescriptions were exclusively hospital issued for 76.2% of the patients. Among the mixed group patients, 91% of treatments were delivered at least once in the community, and 45.6% of biological tests were performed in private laboratories at least once. The sex ratio (2.1 vs. 1.3), the number of patients having switched antiretroviral therapy (36.7% vs. 27.8%), and the frequency of biological tests (3.1 vs. 2.6) were significantly higher in the mixed group compared to the hospital group. The mean compliance was 90% in the hospital group and 91.8% in the mixed group. The compliance was<80% for 104 patients (21.8%). Patients with≥80% compliance were older (46.1years of age vs. 42.7years of age), with more frequent biological tests (3 per year vs. 2.5 per year), and more frequent switches in treatment (35.4% vs. 26.0%).

CONCLUSION

Prescriptions of ARV were almost exclusively hospital issued. Their dispensation and biological tests were split between hospital and extra-hospital settings. Most patients demonstrated an optimal compliance. The CPAM database allows describing HIV management and assessing compliance.