Effect of the physicochemical properties of zinc oxide sources on their bioavailability in broilers

1. The bioavailability of a trace mineral source is related to its intestinal solubility (bioaccessibility), which in turn is determined by its physicochemical properties. It is still not clear which characteristics are more relevant in affecting solubility and bioavailability of mineral sources. Zinc oxide (ZnO) is a common feed additive used to supplement zinc in the diet of monogastric animals. However, different sources have shown variable responses on animal bioavailability.2. This study hypothesised that different sources of feed grade ZnO have various physicochemical features that lead to distinct bioavailability values. Feed grade ZnO samples collected from the feed industry worldwide were characterised for their physicochemical features and tested in broilers to allow bioavailability determined.3. A total of 135 male Cobb broiler chickens were fed a standard starter diet from day 1 after hatching up to d 7. At d 8, animals were allocated in individual cages and fed one of the following dietary treatments during 15 days: a basal diet with 23.5 ppm of zinc and seven test diets with supplemented ZnO or zinc sulphate (ZnSO₄) at 6 or 12 ppm.4. Different sources of ZnO showed an effect of solubility in the stomach and supplementation influenced total Zn levels in the ileum. The bioavailability of the different sources varied from 49% to 160% in relation to ZnSO₄. Aggregate size of particles seems to explain most of the variability in the bioavailability of the different sources tested in broilers. In conclusion, physicochemical properties of ZnO can partly explain the variability observed in terms of biological value.

Prevalence of undiagnosed diabetes and pre-diabetes among hypertensive patients attending Kiambu district Hospital, Kenya: a cross-sectional study

INTRODUCTION

Hypertension (HTN) and diabetes mellitus (DM) are two common non-communicable diseases (NCDs) that are closely linked: one cannot be properly managed without attention to the other. The aim of this study was to determine the prevalence of undiagnosed diabetic and pre-diabetic states that is abnormal glucose regulation (AGR) and factors associated with it among hypertensive patients in Kiambu Hospital, Kenya.

METHODS

We conducted a cross-sectional study from February 2014 to April 2014. Hypertensive patients aged ≥ 18 attending the out-patient medical clinic were included in the study. Pregnant and known diabetic patients were excluded. Data was collected on socio-demographics, behavior, and anthropometrics. Diabetes status was based on a Glycated Haemoglobin (HbA1C) classification of ≥ 6.5% for diabetes, 6.0-6.4% for pre-diabetes and ≤ 6.0% for normal. AGR was the dependable variable and included two diabetic categories; diabetes and pre-diabetes.

RESULTS

We enrolled 334 patients into the study: the mean age was 59 years (Standard deviation = 14.3). Of these patients 254 (76%) were women. Thirty two percent (107/334; 32%) were found to have AGR, with 14% (46) having un-diagnosed DM and 18%(61) with pre-diabetes. Factors associated with AGR were age ≥ 45 (OR = 3.23; 95% CI 1.37 ≥ 7.62), basal metabolic index (BMI) ≥ 25 Kg/m(2) (OR = 3.13; 95% CI 1.53 - 6.41), low formal education (primary/none)(OR= 2; 95%CI 1.08 - 3.56) and family history of DM (OR = 2.19; 95%CI 1.16 - 4.15).

CONCLUSION

There was a high prevalence of undiagnosed AGR among hypertensive patients. This highlights the need to regularly screen for AGR among hypertensive patients as recommended by WHO.