Estimating prevalence of endometritis in smallholder zero-grazed dairy cows in Rwanda

Endometritis is a postpartum uterine disease of cows that interrupts reproductive cycles resulting in suboptimal fertility, reduced performance and profitability of the dairy herd. The objective of the study was to estimate the perceived and observed prevalence of endometritis among zero-grazed dairy cows in smallholder farms in Rwanda. A snowball sampling method was applied in cross-sectional survey to obtain data from 370 farms on 466 cows within their 21–60 days postpartum (dpp). The survey, conducted from September 2018 to March 2019, simultaneously examined cows using the Metricheck Device (MED) to determine the presence and type of vaginal mucus (VMC) based on a score scale of 0 to 3. Cows scoring VMC ≥ 1 were recorded as clinical endometritis (CLE)–positive. Cytotape (CYT) was used to determine the percentages of polymorphonuclear cells (PMN) in endometrial cytology sample. Cows with ≥ 5% PMN were recorded subclinical endometritis (SCLE)–positive, whereas cows with VMC-0 and < 5% PMN were considered healthy cows. At cow-level, endometritis prevalence was 70.2% with 67.2% CLE and 31.8% SCLE while at the herd-level, prevalence was 71.1% with 68.1% CLE and 34.4% SCLE. The differences between the diagnostic performance of the MED and CYT were significant (p < 0.001). Perceived prevalence by farmers was much lower (3.2%) and without agreement with the observed prevalence (kappa = − 0.02, p > 0.05). The highly observed prevalence and farmer underestimation of endometritis prevalence indicate knowledge gaps about endometritis. The extension service therefore needs to increase awareness and education among smallholder farmers about detection and management of endometritis.

     

Identification of appropriate reference genes for qPCR analyses of porcine placentae and endometria,supplying foetuses of different size and sex,at multiple gestational days

Recent studies suggest associations exist between foetal size and sex, and gene expression at the porcine feto-maternal interface. It is essential to identify reference genes which have stable expression throughout gestation in feto-placental units associated with foetuses of different size and sex. qPCR was performed for 11 genes within porcine placentae and endometria at gestational days (GD) 30, 60 and 90. Several reference genes were found to have stable expression in these samples. The combination of B2m1 and Tbp1, and Hprt1 and Tbp1 had the most stable expression in endometria and placentae, respectively. Reference genes identified as having stable expression were utilized in a larger experiment with placentae and endometria associated with foetuses of different size and sex at four GD. The average expression of B2m1 and Tbp1 mRNAs was suitable for the normalization of temporal changes in endometria, and comparison between endometria supplying foetuses of different size throughout gestation. The average expression of Hprt1 and Tbp1 mRNAs was suitable for the normalization of placental mRNA expression for comparison of temporal changes and sex differences between placentae supplying foetuses of different sex throughout gestation. This combination was suitable for the normalization of mRNA expression in placentas supplying GD30, GD60 and GD90 foetuses of different size. This study has identified reference genes with stable expression in placentae and endometria across multiple gestational days, in tissues associated with foetuses of different size and sex. The results of these experiments highlight the importance of selecting appropriate reference genes for the biological comparison under investigation.     

Effects of dietary protein level on muscle cellularity and flesh quality in Atlantic salmon with particular reference to gaping

Growth performance, muscle cellularity and flesh quality were investigated in Atlantic salmon (Salmo salar L.) fed either of two diet ranges [high protein (HP), or low protein (LP)], which differed in digestible protein/digestible energy ratios but were of equivalent digestible energy content (21.4 MJ kg⁻¹ wet weight). Smolts from an early maturing (Lochy) and a late maturing (Mowi) strain were PIT-tagged and reared together in duplicate 5×5×5-m sea cages for each diet. The Lochy and Mowi fish were harvested in May and August, respectively, after 417 and 515 days in seawater. The average body weight of fish in each cage at harvest was in the range 3.8–5.4 kg, with no significant difference between diets. The total cross-sectional area of white muscle and the number and diameter of muscle fibres was determined at the level of the first dorsal fin ray. The distribution of muscle fibre diameters was investigated using nonparametric smoothing and bootstrapping techniques. Diet had no effect on fibre size distribution or fibre number in the Mowi strain, and small but significant effects for the Lochy strain. At harvest, in Lochy salmon of average fork length 69 cm there were around 15% more fibres in fish fed the HP than LP ratio diets. However, the 50th percentile of fibre diameter was 20% greater in fish fed the LP than HP diets, such that the total muscle cross-sectional area was similar. The lipid content (14.1–15.3% wet mass), astaxanthin pigment concentration (7.0–8.5 mg kg⁻¹ wet mass) and colour (RocheSalmoFan™ and Minolta Chromatometer readings) of the flesh were similar for both strains and diets. There was no significant difference in the average muscle fibre density between strains and diet, which varied between 60 and 140 fibres mm⁻² muscle cross-sectional area. Gaping during processing of the fillet was in part related to muscle cellularity. Little or no gaping was observed in any fish with a fibre density in excess of 95 fibres mm⁻² muscle. It was concluded that individual variation in fibre density is important in the development of gaping, but that muscle cellularity and flesh quality are relatively insensitive to the protein to energy ratio in the diet over the range studied.     

Hybridization success of three common European cyprinid species, <Emphasis Type="Italic">Rutilus rutilus,Blicca bjoerkna</Emphasis> and <Emphasis Type="Italic">Abramis brama</Emphasis> and larval resistance to stress tests

ABSTRACT:   Hybridization success at early developmental stages and larval resistance to osmotic, thermal and fasting tests in roach Rutilus rutilus , silver bream Blicca bjoerkna , common bream Abramis brama and their F1 hybrids were investigated. Results revealed that hybrid survival rates were similar to parents. At the eyed embryo stage, however, a maternal effect was observed as a general trend during hatchling and larval stages. After these stages, hybrids displayed a higher survival rate than their parents. Under stress tests, no survival was observed after 40 min for osmotic and thermal shocks and after 24 days for the prolonged fasting test in these species and their F1 hybrids. The median survivals of hybrids were intermediate between the two parents. For total mortality, hybrids were also affected by a maternal effect but to the advantage of the hybrids.     

The effect of translocation and temporary captivity on wildlife rehabilitation success: An experimental study using European hedgehogs (Erinaceus europaeus)

Translocation is frequently used to return rehabilitated animals to the wild, and is an important tool for the population management of endangered species. Whilst experimental field manipulations are important in determining optimal rehabilitation and translocation strategies, they are rarely implemented in practice. We used an experimental approach to examine the effects of translocation on post-release survival and behaviour, and the impact of introductions on the recipient wild population, using the European hedgehog (Erinaceus europaeus), the most common mammal admitted to British wildlife hospitals. The post-release survival and behaviour of five groups were compared: three different translocation treatments, one wild population at the release sites and one control wild population away from the release sites. Individuals that were held in captivity prior to translocation had a better survival rate on release than individuals that were translocated with a minimum time spent in captivity. We suggest that temporary captivity improves chances of survival by allowing the build up of fat reserves and reducing manipulation stress suffered on release. No evidence was found for intra-specific competition between introduced individuals and the recipient wild hedgehog population.     

X-ray photoelectron spectroscopy for wheat powders: measurement of surface chemical composition

The functional properties of wheat powders depend largely on the surface characteristics of their particles. X-ray photoelectron spectroscopy (XPS) has been considered to investigate the surface composition of wheat powders. The objective of the present study is to evaluate the ability of XPS to discriminate wheat components and to calculate the surface composition of wheat powders. First, XPS surveys for the main wheat isolated components (starch, proteins, arabinoxylans, and lipids) were determined. XPS results demonstrate that it is able to distinguish wheat proteins, polysaccharides, and lipids, but it is not able to distinguish starch and arabinoxylan because of their similarity in chemical structure. The XPS analyses of simple reconstituted wheat flours based on two components (starch and protein) or three components (by adding arabinoxylan) demonstrated the ability of XPS to measure the surface composition of the wheat flours. The surface composition of native wheat flour demonstrated an overrepresentation of protein (54%) and lipids (44%) and an underrepresentation of starch (2%) compared to the bulk composition. Results are discussed with regard to difficulties in discriminating arabinoxylans and starch components.     

Earthworm activity alters geogenic arsenic and soil nutrient dynamics

Environmental pollution due to arsenic (As) has been well studied and most investigations have focused on inorganic As coming from industrial areas. However, the natural rock-borne contamination of this metalloid has been underestimated and few studies focusing on annelids have addressed the question of geogenic As distribution in earthworm biogenic structures. Our study concentrated on the earthworm drilosphere and investigated the distribution of As in surface-casts and burrow-linings. In this context, we assumed that the concentration of geogenic As should differ in biogenic structures (faeces, burrow-linings) compared to non-ingested soil. To test our hypothesis, microcosms in controlled conditions were filled with soil containing 157 mg As kg^?1 from a geogenic origin. The soil was collected from a meadow in the Jura Mountains. The earthworm Aporrectodea giardi was selected because of its natural presence in the meadow and its anecic behaviour.We found that while earthworm surface-casts were enriched in carbon, nitrogen and available phosphorus compared to non-ingested soil, no enrichment was found for geogenic arsenic. The coarse sand fraction contained 3.5 times more As than silt and clay fractions but no significant difference existed between surface-casts and non-ingested soil. Iron was shown to be the main mineral bearing phase for As and predominated in the coarse sand fraction. No retention effect of organic matter on geogenic arsenic was observed. In conclusion, it appeared that geogenic As did not affect biological components and environmental aspects. These findings are particularly encouraging considering that most of the environments at an altitude of 1330 m in the Jura Mountains have exposed rocks, especially on meadows that are regularly grazed by cattle.     

Transport across Caco-2 cell monolayer and sensitivity to hydrolysis of two anxiolytic peptides from αs1-casein, α-casozepine, and αs1-casein-f91-97: effect of bile salts

α-Casozepine and f91-97, peptides from α(s1)-casein, display anxiolytic activity in rats and may have to cross the intestinal epithelium to exert this central effect. We evaluated their resistance to hydrolysis by the peptidases of Caco-2 cells and their ability to cross the cell monolayer. To mimic physiological conditions, two preparations of bile salts were used in noncytotoxic concentrations: porcine bile extract and an equimolar mixture of taurocholate, cholate, and deoxycholate. The presence and composition of bile salts appeared to modulate the peptidase activities of the Caco-2 cells involved (i) in the hydrolysis of α-casozepine, leading to much higher formation of fragments f91-99, f91-98, and f91-97, and (ii) in the hydrolysis of f91-97, leading to lower degradation of this peptide. Transport of α-casozepine across Caco-2 monolayer increased significantly, in the presence of bile extract, and of fragment f91-97, in the presence of bile salts.     

Predicting the invasion risk by the alien bee-hawking Yellow-legged hornet Vespa velutina nigrithorax across Europe and other continents with niche models

Vespa velutina nigrithorax, an Asian bee-hawking hornet, has been unintentionally introduced in south-western France before 2004 and is currently widely spreading across the country. Its arrival in northern Spain was reported in 2010. The potential invasion risk of the species is assessed using climatic suitability models. We used eight different modelling techniques within an ensemble forecast framework to show that the invasion success in south-western France could have been predicted using data from the native Asian range of the species, while we further used data from both the native and invaded ranges (including a recently established population in Korea) to better predict its potential invasion range across all continents. Results are discussed in terms of the interest of ecological niche modelling for invasion biology, realised niche of the invasive wasp, potential threats to native entomofauna and economic impacts of this new predator. A particular attention is paid to beekeeping activities that are nowadays already threatened by a wide panel of adversary factors.