Preventive effects of supplemental dietary zinc on heat-induced damage in the epididymis of boars

Hyperthermia in boars reduces growth performance and sperm production. Zinc is an essential trace element in animal nutrition. Here we investigate the effects of dietary zinc on epididymal structure and function in Bama miniature pigs treated with heat exposure and investigate approaches to improve the reproductive performance in summer. Male Bama miniature pigs (n=18; aged 6 months; bodyweight=10.79±0.06 kg) were randomly allocated to 3 groups: control group (Control), heat treatment group (HT), and the diet-supplemented and heat treatment group (H+Zn). The Control and HT groups were fed with basal diet and the H+Zn group were fed with basal diet plus 1500 mg/kg zinc daily. After being fed with these 2 different diets for 30 days, pigs in the HT and H+Zn groups were exposed to 5 h of 40 °C heat treatment for 8 days. Rectal temperature and jugular venous blood were collected 3 h after onset of heat exposure on days 1, 4 and 8. Pigs were sacrificed after the termination of heat exposure. Heat treatment increased serum testosterone concentration on day 1 and 4 (P<0.01). In addition, the HT group displayed an increase in the clear cell count and a decrease in epithelium thickness in the caput epithelium (P<0.01, P<0.05), and dietary zinc protected the boars from these impairments (P<0.01, P=0.29). Evaluation of oxidative states showed that heat exposure increased the levels of malondialdehyde (MDA) and glutathione (GSH) in the epididymis (P<0.01, P<0.05), while dietary zinc reduced this elevation (P<0.01, P<0.01). Heat exposure enhanced the glucocorticoid receptor (GR) expression in the nuclei of principal and basal cells (P<0.01, P<0.01) while dietary zinc attenuated the GR immunoreactivity intensity (P<0.01, P<0.01). These results demonstrate that dietary zinc protects the epididymis from high temperature-induced impairment, alleviates oxidative stress, restores the integrity of the caput epithelium and decreases the stress response.     

Bone microstructure of Vegavis iaai (Aves,Anseriformes) from the Upper Cretaceous of Vega Island,Antarctic Peninsula

Vegavis iaai is a neornithine bird coming from the Late Cretaceous Sandwich Bluff Member of the López de Bertodano Formation (Maastrichtian), Antarctic Peninsula. Vegavis constitutes the only unquestionable Cretaceous neornithine bird, and is known by the holotype and specimen MACN-PV 19.748. The goal of this paper is to present a detailed osteohistological analysis of V. iaai. Vegavis shows a highly vascularized fibrolamellar matrix lacking lines of arrested growths, features widespread among modern birds. This is consistent with previous hypotheses indicating that modern birds were dominant at high latitudes. This is probably related to high-metabolic rates shared by modern birds, whereas archaic taxa as Enantiornithes are absent or form a minority part of High-Latitude bird assemblages. Vegavis was a diver, characterised by a certain degree of limb osteosclerosis, with an increase of bone inner compactness, and inhibition of secondary remodelling, with no effect on the external dimensions of the bone, a combination of characters related to diving lifestyle. Based on Relative Bone Thickness it is possible to infer that Vegavis was a foot-propelled diving bird, similar to some extant anseriforms. Occurrence of osteosclerotic limb bones in Vegavis and Polarornis may constitute a derived shared feature, sustaining the hypothesis that both taxa are phylogenetically related.     

Adequacy of dietary intakes and poverty in India: Trends in the 1990s

Linear programming methods, indicators of nutritional adequacy from the Indian Council of Medical Research and household expenditure survey data from the National Sample Survey Organization were used to construct poverty lines for India. Poverty ratios were calculated for 1993--1994 and 1999--2000 on the basis of nutritional adequacy poverty lines and compared to official estimates of poverty based on energy requirements. Nutritional adequacy poverty lines are higher than official poverty lines, particularly in rural areas. The application of nutritional adequacy poverty lines points to greater rural-urban poverty differences than in official estimates. Declines in rural poverty during the 1990s were also slower under the nutritional adequacy definition, especially in south India. There is a greater degree of rural-urban and regional bias in nutritional adequacy poverty reduction than suggested by official data. Inter-state variations in changes in nutritional poverty and official poverty in the 1990s are largely explained by differences in assumptions on overall price movements. However, relative price movements in food items also played a role, particularly the slow increase in prices of cereals and edible oils in comparison to the prices of pulses, and in some southern states, compared to milk and vegetable prices as well.     

Feeding behaviour in the Antarctic fairy shrimp, <Emphasis Type="Italic">Branchinecta gaini</Emphasis>

Direct observations of feeding behaviour in Branchinecta gaini are described. B. gaini possess sophisticated food manipulation behaviours, using their abdominal appendages to ‘scrape’ at and carry away food items. Scraping behaviour was employed by animals for both detrital feeding and the cannibalisation of dead conspecifics. In the absence of like observations from other non-raptatory species of Branchinecta, it appears that adults of B. gaini occupy an intermediary position between species that feed exclusively on vegetative and detrital material and those (e.g. B. gigas, B. ferox, B. raptor) that are known to be carnivorous. In an Antarctic context, particularly, specialisation towards carnivory would have little adaptive value, while expansion of diet breadth via increased manipulative and digestive flexibility would, on the other hand, be advantageous. These behaviours, moreover, mean that B. gaini plays an active role in the breakdown and recycling of its own nutrient base.     

A record of acorn eating by sika deer in western Japan

The rumen contents of 14 sika deer (Cervus nippon) collected in November 1996 in Yamaguchi Prefecture, the western end of Honshu, Japan, were analyzed by the point-frame method. The contents were composed of high-quality foods like deciduous and evergreen browse and acorns. The composition, which consisted of a significant amount of acorns (27.8 ± 22.5%, mean ± SD), was in contrast to that of northern sika deer populations which exclusively eat graminoid leaves including dwarf bamboos. This is the first record of acorns being a major contributor to diet for wild sika deer. By the point-frame method, acorns were underestimated, and the weight contribution was much greater.     

The role of the pancreas in the regulation of zinc status

A low Zn diet resulted in subacute Zn deficiency in young rats. Thirty minutes after the intubation of a trace 65-Zn we determined the total tissue Zn activity in plasma, erythrocytes, liver, pancreas, bone, muscle, and proximal jejunum. Assuming the body behaved like a closed multicompartmental system in steady state, we estimated the initial Zn exchange between plasma, and the erythrocytes or these tissues. In comparison with control animals the exchanges between plasma and erythrocytes or pancreas increased threefold during subacufe Zn deficiency. In the pancreas the ratio also reversed from <1.0 to>1.0. This confirmed earlier, observations that the specific activity (kBq 65-Zn/mol Zn) increased mostly in the pancreas. By increased net Zn uptake during subacute deficiency, the pancreas Zn content remained constant in chronic Zn deficiency. We discussed the regulation of the Zn status by the pancreas. We hypothesize that the exocrine pancreas modulates Zn absorption by an exocrine ligand that enhances absorption in the jejunum during subacute deficiency: Unsaturated with Zn it binds dietary intraluminal Zn and increases the Zn absorption. The literature provides evidence in confirmation. This hypothesis explains also conflicting data on the inherited Zn malabsorption syndrome Acrodermatitis Enteropathica.