Stress Reactivity and Coping in Horse Adaptation to Environment

“Coping” or “coping strategy”, defined as the behavioral and physiological efforts of animal to master the situation, is more and more in interest of researchers dealing with applied animal behavior and welfare. Knowledge about “coping styles” may be helpful in understanding individual adaptive capacity to stressful events. At least two types of animal coping strategy (or coping style) can be involved: (1) active copers (proactive) and (2) passive copers (reactive). The individual differences in stress response to threatening situations have been found in horses, and these animals can show specific coping strategies such as other species. This article reviews the set of behavioral, psychoneuroendocrine, and psychoneuroimmune mechanisms involved in animal adaptation to environmental challenges and discusses the relationship between behavioral and physiological factors involved in stress response of the horse. Exploring coping strategies in horses and in any captive animal can be successful when a multidimensional approach including behavioral, neural, hormonal, and hematological measures is considered. Knowledge on stress coping styles can provide valuable information to predict the behavior of individuals during response to specific challenging situations. Moreover, assessing individual differences in adaptation strategies can be useful in horse selection to different exploitation tasks and reproduction.     

Chokeberry polyphenols reduce prooxidative influence of oxidized fats in rat diets

The aim of the study was to estimate nutritional and physiological consequences of combined supplementation of rat casein diets with a strongly oxidized mixture of fats and extract of polyphenols from chokeberry. The experiment was conducted on 80 young Wistar rats divided into 8 groups. The animals were fed diets supplemented with 8% of fresh or oxidized fats and 0.4, 0.8 and 1.2% of polyphenol extract together. Addition of the oxidized fats caused significant reduction in animal growth without a decrease in nitrogen digestibility. On the other hand, the extract of polyphenols suppressed nitrogen utilization; animal growth was however similar to the control group. Analysis of the variance showed negative influence of the oxidized fats on cholesterol and triacyloglycerol concentration in the blood of the experimental animals. Increased activity of both aminotransferases in the blood of rats fed diets containing the oxidized fats indicated on liver malfunction. There was no effect of the experimental factors on the antioxidant status of the blood, but a dose-dependent reduced content of malonylodialdehyde in the blood of rats fed diets supplemented with the extract of polyphenols suggested that the extract had a preventive effect against prooxidative activity of the oxidized fats.     

Differential effects of heparin on NO and tumor necrosis factor-alpha production in bovine blood mononuclear cells stimulated with Salmonella typhimurium lipopolisaccharide.

We investigated the influence of heparin, one of the extracellular matrix (ECM) components, on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by bovine peripheral blood mononuclear cells (PBMC) and monocytes left to adhere for 2 (freshly adherent monocytes) and 48 h (resting monocytes), activated with Salmonella typhimurium lipopolysaccharide (LPS). After 24-h stimulation with LPS, heparin (100 microg/ml) increased (by about 40%) NO production by peripheral blood mononuclear cells and by freshly adherent monocytes. However, it did not change NO synthesis by the resting monocytes. Unlike its influence on NO level, heparin diminished TNF-alpha production by PBMC and monocytes stimulated with LPS. Microscopical examination of PBMC stained with biotin-labeled heparin, showed that both lymphocytes and monocytes were able to bind this glycosaminoglycan. We suggest that heparin, as a component of ECM, modulates the early response of monocytes to exogenous stimuli.     

Canine spermatozoa—What do we know about their morphology and physiology? An overview

Spermatozoa are unique cells because of their morphological and physiological characteristics. They are produced during the process called spermatogenesis. Spermatogenesis consists of three phases: spermatocytogenesis, spermiogenesis and spermiation, during which spermatozoa undergo several changes. Spermatogenesis takes place within the seminiferous tubules containing two types of cells—the germ cells and the Sertoli cells—that alongside the Leydig cells, which play an important role when it comes to normal fertility. Everything is regulated by the hypothalamic–pituitary–gonadal axis and specific hormones due to multi-hormonal feedback systems. Spermatozoa possess morphological and physiological features, which are sometimes completely different from what is observed in various somatic cells. What is more, canine spermatozoa have specific characteristics making them special compared to the spermatozoa of other mammalian species. The metabolic energy production, which is crucial for the appropriate functioning of spermatozoa, can be fuelled by different metabolic pathways utilizing different chemical substrates. Inseparable from the oxidative phosphorylation process is the production of reactive oxygen species, which are both essential and toxic to spermatozoa. Furthermore, epididymis is a very important structure, responsible for the transport and maturation of spermatozoa, which are then stored in the last segment of epididymis—the epididymal cauda. Moreover, the retrieval of spermatozoa from the epididymides is crucial for the development of assisted reproduction techniques and sperm cryopreservation methods. The information gained from the research on domestic dogs might be transferred to their wild relatives, especially those species categorized as endangered.     

The effect of Lactobacillus acidophilus and Bifidobacterium spp. administration on the morphology of the gastrointestinal tract, liver and pancreas in piglets

The aim of the study was to investigate the influence of administration of probiotic bacteria on morphology of the gastrointestinal tract, liver and pancreas. The experiment was performed on 15 piglets at the age from 3 to 35 days, intragastrically administered with Bifidobacterium breve, B. animalis, and Lactobacillus acidophilus bacteria. In all piglets examined, the development of the gastrointestinal tract, liver and pancreas was observed to progress normally. After microflora administration to the piglets, an increase in the number of fibrocytes and fibroblasts was observed in the mucosa lamina propria of stomach and intestines. An increase was also reported in the number and activation of endocrine cells in the stomach and small intestines. The activity of alkaline and acid phosphatases, as well as succinic (SDH) and lactic (LDH) dehydrogenases, was found to be higher after the administration of probiotics. The administration of bacteria, especially of Lactobacillus acidophilus, caused an increase in the number of lymphocytes and lymphoid cells in lamina propria and intraepithelial lymphocytes in the small intestine. Enhanced proliferation of crypt cells was observed in the crypts of intestinal glands; however, there were no statistically significant differences in the PCNA index between the control and probiotic-administered groups. The performed study showed that the administration of probiotic bacteria has no negative impact on the morphology of the gastrointestinal tract, liver and pancreas and is found beneficial to its functioning and immune processes.     

Relationship between somaclonal variation and type of culture in cucumber

Highly inbred B line of cucumber was used to compare the effect of four types of in vitro culture on somaclonal variation. The plants were regenerated from the following types of culture: twelve- and eighteen-month-old liquid culture of meristematic clumps (LMC₁₂₍₁₈₎), ten-month-old embryogenic cytokinin-dependent suspension (CDS), eighteen-month-old embryogenic cytokinin-dependent suspension in medium with modified NH⁺ ₄/NO₃ ^- ratio (CDS 1.7), twelve-month-old embryogenic auxin-dependent suspension (ADS), thirty six-month-old embryogenic auxin-dependent suspension in medium with modified NH⁺ ₄/NO₃ ^- ratio (ADS 1.7) and recurrent leaf callus regeneration (RLC) – repeated 5 times. The differences in the incidence of the following properties were observed: the ploidy of R₀ plants, the segregation of new morphological traits in R₁ and the germination ability of R₁ seeds. R₁ families with the segregation of new phenotypes were most numerous in CDS (62.5%) and LMC₁₈ (57.9%), next in CDS1.7 (35.7%), while the smallest number was found in LMC₁₂ (11.1%) and RLC (3.4%).Tetraploid and mixoploid plants occurred in ADS1.7 and ADS (100%) whereas CDS and RLC were observed to contain only tetraploids, respectively 33.3% and 55.2%. There were no changes of ploidy after LMC₁₂, LMC₁₈ and CDS1.7. Among new phenotypes there were such that have not been described so far in cucumber: ginkgolike leaf (gll), yellow-green chlorophyll mutants (y-gc), serrate margin of corolla in male and female flowers (smc). This revised version was published online in August 2006 with corrections to the Cover Date.     

Mapping of the <Emphasis Type="Italic">ms8</Emphasis> male sterility gene in sweet pepper (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) on the chromosome P4 using PCR-based markers useful for breeding programmes

The nuclear male sterility gene ms8 is expected to facilitate the production of sweet pepper (Capsicum annuum L.) hybrids as it provides means for hybridization without the labor-intensive hand emasculation of female inbred lines. The development of molecular markers linked to ms8 locus will help the breeding practice for the selection of hybrid parental lines. In this study, F₂ population resulting from a cross between the sweet pepper male sterile line 320 and the male fertile variety Elf was used to identify DNA markers linked to the ms8 locus. With the use of RAPD–BSA technique, seven markers linked to the ms8 locus were found. Four of them were converted into SCAR markers. In addition, two COSII/CAPS markers linked to the ms8 locus were identified. Comparative mapping with reference pepper maps indicated that the ms8 locus is located on the lower arm of the pepper chromosome P4. Identified markers are useful for molecular breeding, however, at present markers tightly linked to ms8 locus are still lacking. Identification of molecular markers linked to the ms8 locus and determination of its chromosomal localization are useful for fine mapping and also provide the perspective for ms8 gene cloning.     

Predicting the Concentration of Total Mercury in Mineral Horizons of Forest Soils Varying in Organic Matter and Mineral Fine Fraction Content

In this study, an artificial neural networks (ANN) model was developed to predict the removal of a polycyclic aromatic hydrocarbon (PAH), namely, naphthalene from marine oily wastewater by using UV irradiation. The removal rate was used as model output and simulated as a function of five independent input variables, including fluence rate, salinity, temperature, initial concentration and reaction time. The configuration of the ANN model was optimized as a three-layer feed-forward Levenberg–Marquardt backpropagation network with log-sigmoid and linear transfer functions at the hidden (12 hidden neurons) and output layers, respectively. By considering goodness-of-fit and cross validated predictability, the ANN model was trained to provide good overall agreement with experimental results with a slope of 0.97 and a correlation of determination (R ²) of 0.943. Sensitivity analysis revealed that fluence rate and temperature were the most influential variables, followed by reaction time, salinity and initial concentration. The findings of this study showed that neural network modeling could effectively predict the behavior of the photo-induced PAH degradation process.