Thwarting of behaviour in different contexts and the gakel-call in the laying hen

Earlier studies have shown that thwarting of feeding behaviour in the laying hen is expressed through a specific vocalisation, the gakel-call. The first aim of this study was to investigate whether the effect of deprivation per se on the occurrence of gakel-calls can be distinguished from the effect of the additional frustration. Frustration is defined as the state of an animal that results from nonreward in the expectancy of reward. The second aim was to investigate whether the occurrence of gakel-calls is restricted to a food context or whether it can be regarded as an expression of frustration in general. For this purpose, 20 hens were deprived of food, water and dustbath. After deprivation at a fixed time, a cue was given and the hens were rewarded with access to food, water or dust during a 15-min session on 4 consecutive days. On the fifth day, they were thwarted in the associated behaviours by blocking the access to these commodities, after the hens had been presented the signal that previously preceded the reward. We then recorded behaviours that might reflect the state of frustration in three 15-min periods. The period "Pre-Frustration" started 15 min before "Frustration". This, in turn, was followed by the period "Post-frustration" in which the hens were rewarded again. Nesting behaviour was thwarted by blocking the access to the nest (Frustration) after a hen had reached the last stage of its prelaying behaviour.In the food, water and dustbath context, deprivation elicited gakel-calls. The additional frustration resulted in a higher number of gakel-calls in all contexts except the food context. However, together with the findings of previous experiments, the results of this study suggest that frustration, in general, is expressed through the gakel-call. Frustration in the nest context elicited more gakel-calls than the other contexts. This latter finding is discussed in the light of the occurrence of the gakel-call under natural circumstances.     

A mRNA landscape of bovine embryos after standard and MAPK-inhibited culture conditions: a comparative analysis

Background

Genes and signalling pathways involved in pluripotency have been studied extensively in mouse and human pre-implantation embryos and embryonic stem (ES) cells. The unsuccessful attempts to generate ES cell lines from other species including cattle suggests that other genes and pathways are involved in maintaining pluripotency in these species. To investigate which genes are involved in bovine pluripotency, expression profiles were generated from morula, blastocyst, trophectoderm and inner cell mass (ICM) samples using microarray analysis. As MAPK inhibition can increase the NANOG/GATA6 ratio in the inner cell mass, additionally blastocysts were cultured in the presence of a MAPK inhibitor and changes in gene expression in the inner cell mass were analysed.

Results

Between morula and blastocyst 3,774 genes were differentially expressed and the largest differences were found in blastocyst up-regulated genes. Gene ontology (GO) analysis shows lipid metabolic process as the term most enriched with genes expressed at higher levels in blastocysts. Genes with higher expression levels in morulae were enriched in the RNA processing GO term. Of the 497 differentially expressed genes comparing ICM and TE, the expression of NANOG, SOX2 and POU5F1 was increased in the ICM confirming their evolutionary preserved role in pluripotency. Several genes implicated to be involved in differentiation or fate determination were also expressed at higher levels in the ICM. Genes expressed at higher levels in the ICM were enriched in the RNA splicing and regulation of gene expression GO term. Although NANOG expression was elevated upon MAPK inhibition, SOX2 and POU5F1 expression showed little increase. Expression of other genes in the MAPK pathway including DUSP4 and SPRY4, or influenced by MAPK inhibition such as IFNT, was down-regulated.

Conclusion

The data obtained from the microarray studies provide further insight in gene expression during bovine embryonic development. They show an expression profile in pluripotent cells that indicates a pluripotent, epiblast-like state. The inability to culture ICM cells as stem cells in the presence of an inhibitor of MAPK activity together with the reported data indicates that MAPK inhibition alone is not sufficient to maintain a pluripotent character in bovine cells.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1448-x) contains supplementary material, which is available to authorized users.     

Corneal iridescence in fishes: light-induced colour changes in relation to structure

The iridescent corneas of 31 species of teleost fish were investigated for light-induced colour changes. Thirteen were found to shift the spectral reflection of their corneas to shorter wavelengths when dark-adapted and to longer wavelengths when illuminated. The structures of the corneas were examined by electron microscopy and categorized according to the type of structure modified to produce the iridescence. Six previously identified structures were found and a seventh type is described here.     

Ontogenetic changes in retinal structure and visual acuity: a comparative study of coral-reef teleosts with differing post-settlement lifestyles

Changes in retinal structure during settlement were investigated in four species of tropical reef-associated teleost fishes with differing periods of planktonic duration and post-settlement lifestyles. They were: Apogon doederleini (Apogonidae), a nocturnal planktivore; Stethojulis strigiventer (Labridae), a diurnal microcarnivore; Upeneus tragula (Mullidae), a carnivore which uses chin barbels to disturb invertebrates from the sediment; and Pomacentrus moluccensis (Pomacentridae), a diurnal herbivorous planktivore. The densities of cones, rods, cells in the inner nuclear layer and cells in the ganglion cell layer were estimated in a size range of each species. Visual acuity was calculated using cone densities and lens diameter. The ontogenetic sequence of changes in cell density was similar in all species but interspecific variation in the timing and rates of change was found and could be related to lifestyle. For example, cone densities decreased and rod densities increased most rapidly in the nocturnal species, A. doederleini, during settlement. In contrast, high cone densities were maintained in the species adopting a diurnal lifestyle. Theoretical visual acuity was found to increase rapidly as lens size increased, but was similar for all species at similar lens sizes, indicating the importance of larger eye size as a means for improving resolution during early stages of eye growth. It was concluded that for the species undergoing abrupt lifestyle changes at settlement, structural re-organisation of the retina is important for the survival of the fish as they leave the pelagic environment and take up their reef-associated lifestyle.     

Treatment-Seeking for Tuberculosis-Suggestive Symptoms: A Reflection on the Role of Human Agency in the Context of Universal Health Coverage in Malawi

Tuberculosis (TB) is highly infectious and one of the leading killers globally. Several studies from sub-Saharan Africa highlight health systems challenges that affect ability to cope with existing disease burden, including TB, although most of these employ survey-type approaches. Consequently, few address community or patient perspectives and experiences. At the same time, understanding of the mechanisms by which the health systems challenges translate into seeking or avoidance of formal health care remains limited. This paper applies the notion of human agency to examine the ways people who have symptoms suggestive of TB respond to and deal with the symptoms vis-à-vis major challenges inherent within health delivery systems. Empirical data were drawn from a qualitative study exploring the ways in which notions of masculinity affect engagement with care, including men’s well-documented tendency to delay in seeking care for TB symptoms. The study was carried out in three high-density locales of urban Blantyre, Malawi. Data were collected in March 2011 –March 2012 using focus group discussions, of which eight (mixed sex = two; female only = three; male only = three) were with 74 ordinary community members, and two (both mixed sex) were with 20 health workers; and in-depth interviews with 20 TB patients (female = 14) and 20 un-investigated chronic coughers (female = eight). The research process employed a modified version of grounded theory. Data were coded using a coding scheme that was initially generated from the study aims and subsequently progressively amended to incorporate concepts emerging during the analysis. Coded data were retrieved, re-read, and broken down and reconnected iteratively to generate themes. A myriad of problems were described for health systems at the primary health care level, centring largely on shortages of resources (human, equipment, and drugs) and unprofessional conduct by health care providers. Participants consistently pointed out how the problems could drive patients from promptly reporting symptoms at primary healthcare centres. The accounts suggest that in responding to illness symptoms including those suggestive of TB, patients navigate their options taking into cognisance past and current experiences with formal health systems. Understanding and factoring in the mediating role of such ‘agency’ is critical when implementing efforts to promote timely response to TB-suggestive symptoms.     

Alpha-sarcoglycan is recycled from the plasma membrane in the absence of sarcoglycan complex assembly

The sarcoglycan complex consists of four subunits in skeletal muscle (alpha, beta, gamma, and delta-SG). Mutations in alpha-sarcoglycan (alpha-SG) result in the most common form of limb girdle muscular dystrophy. However, the function of alpha-SG remains unknown. In this report we attempt to clarify its function by delineating the trafficking pathway of alpha-SG in live cells. We present evidence, utilizing total internal reflection microscopy, fluorescence recovery after photobleaching and photoactivation of green fluorescent protein (GFP) constructs, that pools of alpha-SG are able to translocate to the plasma membrane in the absence of the remaining sarcoglycans. Internalization assays and drug treatment experiments demonstrate that alpha-SG recycles from the plasma membrane and accumulates in recycling endosomes. We also establish that alpha-SG utilizes well-described clathrin mediated mechanisms and microtubules to traffic within the cell. Finally, we show that the most commonly reoccurring limb girdle muscular dystrophy (R77C) mutation causes a fundamental defect in protein biosynthesis, trapping the mutant protein in the endoplasmic recticulum (ER). These results demonstrate that alpha-SG requires assembly into the sarcoglycan complex for stability at the plasma membrane rather than export out of the ER. Furthermore, this data suggests that alpha-SG utilizes known trafficking machinery to control deposition at the plasma membrane through recycling.     

The effects of sheep faeces on soil solution composition

To elucidate changes occurring in soil solution under sheep faeces we collected faeces from sheep grazing on an improved podzol in Scotland in summer and re-applied it (150 g of fresh weight) to patches, each with an area of 0.018 m². Faeces and/or intact soil cores (0–50 mm deep) from underneath the patches were sampled at intervals up to 224 days and nutrients measured in the soil solution isolated by centrifugation. The treatment with faeces increased the soil solution concentrations of P, N, dissolved organic carbon (DOC), Ca, Mg and K. The greatest increases occurred at day 56 for P, Ca, Mg and K, day 84 for N, and day 112 for DOC. Most of the P in the faeces applied to the soil was in inorganic form, but organic P made a substantial proportion (nearly 50%) of the P in soil solution at the time of maximum effect. The faecal residue became indistinguishable from the soil between 84 and 112 days following periods of persistent rainfall. The data provides a new insight into the effects of sheep faeces on soil solution composition unperturbed by chemical extraction and a contrast with the effects of sheep urine on soil solution composition.Section Editor: N.J. Barrow     

Chemical immobilization of adult female Weddell seals with tiletamine and zolazepam: effects of age, condition and stage of lactation

Background

Postweaning diarrhoea (PWD) in pigs is usually the main infectious problem of large-scale farms and is responsible for significant losses worldwide. The disease is caused mainly by enterotoxigenic E. coli (ETEC) and Shiga-toxin producing E. coli (STEC). In this study a total of 101 E. coli isolated from pigs with PWD in Slovakia were characterized using phenotypic and genotypic methods.

Results

These 101 isolates belonged to 40 O:H serotypes. However, 57% of the isolates belonged to only six serotypes (O9:H51, O147:H-, O149:H10, O163:H-, ONT:H-, and ONT:H4), including two new serotypes (O163:H- and ONT:H4) not previously found among porcine ETEC and STEC isolated in other countries. Genes for EAST1, STb, STa, LT and Stx2e toxins were identified in 64%, 46%, 26%, 20%, and 5% of isolates, respectively. PCR showed that 35% of isolates carried genes for F18 colonization factor, and further analyzed by restriction endonuclease revealed that all of them were F18ac. Genes for F4 (K88), F6 (P987), F17, F5 (K99), F41, and intimin (eae gene) adhesins were detected in 19 %, 5%, 3%, 0.9%, 0.9%, and 0.9% of the isolates, respectively. The study of genetic diversity, carried out by PFGE of 46 representative ETEC and STEC isolates, revealed 36 distinct restriction profiles clustered in eight groups. Isolates of the same serotype were placed together in the dendrogram, but high degree of polymorphism among certain serotypes was detected.

Conclusion

Seropathotype O149:H10 LT/STb/EAST1/F4 (14 isolates) was the most commonly detected followed by O163:H- EAST1/F18 (six isolates), and ONT:H4 STa/STb/Stx2e/F18 (five isolates). Interestingly, this study shows that two new serotypes (O163:H- and ONT:H4) have emerged as pig pathogens in Slovakia. Furthermore, our results show that there is a high genetic variation mainly among ETEC of O149:H10 serotype.     

The lipid composition of ovine placental tissue homogenate and its subcellular fractions

Homogenates of the placental tissue of near term sheep were separated by differential centrifugation into mitochondrial, microsomal and cytosolic fractions. The relative proportions of the major neutral lipids and phospholipids, together with their fatty acid compositions, were determined in the homogenates and in each subcellular fraction. The cytosolic fraction contained the highest proportion of cholesteryl esters (CEs) and these possessed a fatty acid composition markedly different from the total CEs extracted from the homogenate. Both the mitochondrial and microsomal fractions contained significant proportions of solvent front phospholipid (SFP) and whereas the mitochondrial SFP displayed the relatively unsaturated fatty acid composition characteristic of diphosphatidylglycerol (cardiolipin), the fatty acids of the microsomal SFP were distinctly more saturated. These results are compared with those obtained from other mammalian tissues, both ruminant and non-ruminant, and discussed in terms of the function of the components of the subcellular fractions.