Influence of the Level of Sex Hormones in the Blood of Gilts on Slaughter Characteristics and Meat Quality.

The aim of the conducted research was to determine the impact of factors such as sex hormone levels, which vary during gilts' reproductive cycle, on the quality of the obtained meat and slaughter characteristics of the processed gilts. The research material included a population of 60 gilts slaughtered in one of the slaughterhouses located in south-eastern Poland. After the slaughtering operations were completed, the carcasses were weighed at the classification stand. The results of the statistical evaluation of the haematological and biochemical blood parameters of the examined gilts showed that, in the tested blood samples, the concentration of progesterone had a statistically significant impact only on the level of total protein, which was higher in the blood samples of gilts with a low concentration of progesterone. It was found that carcasses of gilts with higher levels of the LH hormone were characterized by a lower meat content index by nearly 3%. It was shown that the concentration of LH affected the post-slaughter temperature of the sirloin and ham muscles. The interpretation of the obtained data was difficult since there seems to be a gap in the literature concerning the dependencies of sex hormone levels in gilts and meat quality.

The effect of ZnO nanoparticles on rabbit spermatozoa motility and viability parameters in vitro.

Zinc plays a very important role in various biological activities of the body. Multifaceted role of zinc is also known in testes development, spermatogenesis, capacitation and has effect on spermatozoa motility. On the other hand, the growing industry of nanotechnology has created reasonable interest of the risk assessment for nanoparticles. The aim of this study was to evaluate in vitro effect of zinc oxide (ZnO) nanoparticles on rabbit spermatozoa. Fresh semen was collected from sexually mature New Zealand rabbits. Experimental groups were prepared by diluting semen with ZnO nanoparticles in seven different concentrations (6-391 mg/mL). The experimental groups were compared with control group. Semen was assessed using computer assisted semen analysis (CASA) at intervals of 0, 1, 2 and 3 h of incubation. The mitochondrial toxicity assay (MTT) assay was used to determine cell viability. The results of monitored motility parameters in experimental groups showed a decreasing trend during whole experiment. Significant decrease (P < 0.001) of motility and progressive motility was observed after 3 h of incubation in samples cultured with higher ZnO nanoparticles in comparison to the control group. After 3 h of incubation, viability of rabbit spermatozoa showed slightly increased values in group with the lowest concentration of ZnO nanoparticles, but in other groups viability showed non-significant decrease compared to control. Similar tendency was detected for spermatozoa membrane integrity. These original data show the negative dose-dependent effect of ZnO nanoparticles on spermatozoa motility and viability parameters.

Mechanism of nutrition activity of a microgranule fertilizer fortified with proteins.

BACKGROUND: A microgranule fertilizer was designed for localized fertilization of soil with controlled release of nutrients. The microgranule matrix was fortified with proteins, which were obtained from food industry byproducts or waste, i.e., whey protein from milk serum, soy protein from soy isolate and egg white protein from chicken egg white powder. The mechanism of the protein decomposition and migration of micro and macromolecule compounds through two different model soil systems was investigated. The potential of the protein fortified fertilizer for localized fertilization of the potted maize seeds was evaluated. RESULTS: The study revealed that proteins slowly diffused through soil with simultaneous degradation, which was accompanied with release of ammonia ions. The highest concentration of proteins and degradation products was found in a close vicinity of the microgranule. The microgranules were used as a local fertilizer for maize seeds in the pot experiments. The experiments confirmed statistically significant improvement in root density of maize plant compared to control group. CONCLUSIONS: Byproducts or waste of food industry, such as the milk serum and soy can be used as a source of proteins that degrade in soil without a pretreatment. The degradation is accompanied with formation of ammonium ions, which can be utilized by plants as a nitrogen source. The fertilizer microgranule should be placed in a close vicinity to the plant seed, since the maximum of the protein concentration and ammonia ions is reached at a very close distance from the microgranule.

Effects of PCB 126 and PCB 153 on secretion of steroid hormones and mRNA expression of steroidogenic genes (STAR, HSD3B, CYP19A1) and estrogen receptors (ERα, ERß) in prehierarchical chicken ovarian follicles.

The objective of this study was to assess the in vitro effects of dioxin-like PCB 126 and non-dioxin-like PCB 153 on basal and ovine LH (oLH)-stimulated testosterone (T) and estradiol (E2) secretion and expression of steroidogenic genes (STAR, HSD3B and CYP19A1) and estrogen receptors α (ERα) and ß (ERß) in white (WF) and yellowish (YF) prehierarchical follicles of the hen ovary. Steroid concentrations in a medium and gene expression in follicles following 6h of exposition were determined by RIA and real-time qPCR, respectively. Both PCBs increased basal and oLH-stimulated T secretion by the WF follicles. PCB 126 reduced basal E2 secretion by the WF follicles. PCB 153 elevated but PCB 126 reduced oLH-stimulated E2 secretion by the prehierarchical follicles. PCB 126 increased basal STAR and HSD3B and reduced CYP19A1 mRNA expression in these follicles. PCB 153 increased basal expression of STAR and HSD3B in YF follicles, but diminished HSD3B mRNA levels in the WF. The studied PCBs had an opposite effect on basal and oLH-stimulated CYP19A1 mRNA expression in prehierarchical follicles. Both PCBs modulated basal and inhibited oLH-stimulated ERα and ERß gene expression in the prehierarchical follicles. In conclusion, data of the current study demonstrate the congener-specific effects of PCBs on sex steroid secretion by prehierarchical follicles of the chicken ovary, which are at least partly related to STAR, HSD3B and CYP19A1 gene expression. It is suggested that PCBs, by influencing follicular steroidogenesis and expression of estrogen receptors, may impair development and selection of yellowish follicles to the preovulatory hierarchy.

Effect of PCB 126 on aryl hydrocarbon receptor 1 (AHR1) and AHR1 nuclear translocator 1 (ARNT1) mRNA expression and CYP1 monooxygenase activity in chicken (Gallus domesticus) ovarian follicles.

The aim of the experiment was to study the in vitro effect of 3,3',4,4',5-pentachlorobiphenyl (PCB 126; a coplanar PCB congener) on aryl hydrocarbon receptor (AHR1) and AHR1 nuclear translocator (ARNT1) mRNA expression and the activity of CYP1 family monooxygenases in chicken ovarian follicles. White (1-4 mm) and yellowish (4-8 mm) prehierarchical follicles as well as fragments of the theca and granulosa layers of the 3 largest preovulatory follicles (F3-F1) were incubated in a medium supplemented with 0 (control group), 1, 10 or 100 nM PCB 126. The incubation was carried out for 6 h or 24 h for determination of mRNA expression of AHR1 and ARNT1 genes (real-time qPCR) and CYP1 monooxygenase activity (EROD and MROD fluorometric assays), respectively. It was found that chicken ovarian follicles express mRNA of AHR1 and ARNT1 genes. A modulatory effect of PCB 126 on AHR1 and ARNT1 expression depended not only on the biphenyl concentration but also on the follicular layer and the maturational state of the follicle. EROD and MROD activities appeared predominantly in the granulosa layer of the yellow preovulatory follicles. PCB 126 induced these activities in a dose-dependent manner in all ovarian follicles. The obtained results suggest that ovarian follicles, especially the granulosa layer, are involved in the detoxification process of PCBs in the laying hen. Taking this finding into consideration it can be suggested that the granulosa layer of the yellow hierarchical follicles plays a key role in the protective mechanism which reduces the amount of transferred dioxin-like compounds into the yolk of the oocyte.

Expression of aryl hydrocarbon receptor 1 (AHR1), AHR1 nuclear translocator 1 (ARNT1) and CYP1 family monooxygenase mRNAs and their activity in chicken ovarian follicles following in vitro exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

The aim of this in vitro study was to determine the effect of TCDD and luteinizing hormone (LH) on mRNA expression of aryl hydrocarbon receptor 1 (AHR1), AHR1 nuclear translocator 1 (ARNT1), and the CYP1 family monooxygenases (CYP1A4, CYP1A5, CYP1B1), and to assess the basal and TCDD-induced activity of these enzymes in chicken ovarian follicles. White (WF) and yellowish (YF) prehierarchical follicles and fragments of the theca (TL) and granulosa (GL) layers of the 3 largest preovulatory follicles (F3-F1) were exposed to TCDD (10nM), ovine LH (oLH; 10ng/mL) or a combination of TCDD (10nM) and oLH (10ng/mL), and increasing doses of TCDD (0.01-100nM). AHR1 and ARNT1 mRNA transcripts were found in all examined follicles. The effect of TCDD and oLH on AHR1 and ARNT1 mRNA expression depended on the maturational state of the follicle. CYP1A4 was predominantly expressed in the GL of the F3-F1 follicles; in comparison with the WF, a higher level of CYP1A5 mRNA was found both in the GL and TL of F3-F1 follicles. Alternatively, the highest level of CYP1B1 mRNA was noticed in the WF follicles. In different developmental stages of the follicle TCDD and oLH induced a different CYP1 isoform. TCDD increased EROD and MROD activities in all the investigated ovarian follicles. In conclusion, AHR1 and ARNT1 mRNA expression indicate that the chicken ovary is a target tissue for dioxin and dioxin-like compounds. The expression of CYP1-family genes and TCDD-inducible EROD and MROD activities in ovarian follicles suggest the possibility of xenobiotic detoxification in the chicken ovary.

Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on secretion of steroids and STAR, HSD3B and CYP19A1 mRNA expression in chicken ovarian follicles.

The aim of the study was to investigate the in vitro effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on steroid hormone secretion by chicken ovarian follicles and mRNA expression of genes involved in steroids synthesis. In the first in vitro experiment, white (WF) and yellowish (YF) follicles and fragments of the theca (TL) and granulosa (GL) layers of the 3 largest yellow preovulatory follicles (F3-F1) were incubated in a medium supplemented with TCDD (0.01-100nM). In the second experiment, they were incubated in a medium with TCDD (10nM), ovine LH (10ng/mL; oLH) or a combination of oLH (10ng/mL) and TCDD (10nM). It was found that TCDD decreased estradiol (E2) secretion by WF and the TL of all preovulatory follicles, testosterone (T) secretion by WF, YF, and the TL of F2 and F1 follicles, and progesterone (P4) secretion by the GL of the preovulatory follicles. It also reduced oLH-stimulated E2 and P4 secretion by all examined follicles and T by WF. Real-time qPCR revealed that TCDD affected basal and oLH-stimulated expression of STAR, HSD3B and CYP19A1 mRNAs in all investigated ovarian follicles. In conclusion, the data obtained indicate that TCDD inhibits sex steroids secretion from chicken ovarian follicles. The effects of TCDD depend on its concentration and the stage of follicle maturation, and are associated with modulation of STAR, HSD3B and CYP19A1 mRNAs expression. These results indicate that the exposure of the laying hen to TCDD by influence of ovarian steroidogenesis may impair the selection of white follicles to preovulatory hierarchy and disturb their growth and preovulatory maturation.

Potential of ozone utilization for reduction of pesticide residue in food of plant origin. A review.

Residues of plant protection products can be nowadays found in almost all samples of fruits as even if their application was carried out with respect to standards of Good Agricultural Practice. The intake of these compounds with food of plant origin may result in various disorders and diseases. Since the use of plant protection agents seems unavoidable, it is necessary to treat contaminated food material to eliminate or reduce residues content within food products. Ozone is utilized for elimination of biological and chemical contaminants in various environmental matrixes. Since its utilization in food industry has been permitted many experiments were conducted in order to determine its efficiency and side effects on food quality. The goal of this paper is to contribute to a discussion on the ozonization as a process leading to reduction of pesticide residues on plant surface.