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Open access

Somayeh Kianpoor, Alireza Abdolmohammadi, Hadi Hajarian, Zahra Nikousefat and Hasan Khamisabadi

Abstract

The purpose of this study was to identify mutations in melatonin receptor 1A (MTNR1A) and aromatase cytochrome P450 (CYP19) genes using PCR-RFLP technique and their associations with sperm quality and testicular size traits in Sanjabi breed rams. The blood and sperm samples were collected from Sanjabi rams (n = 96). Genomic DNA was extracted from the blood. A 824bp fragment from exon II of MTNR1A gene and a 517bp fragment from promoter 2 (P2) of CYP19 gene were amplified using two pairs of specific primers. The PCR products were separately digested by two restriction enzymes, SsiI for MTNR1A locus and DraI for CYP19 locus. Digestion by SsiI restriction enzyme resulted in CC, CA and AA genotypes with frequency of 0.45, 0.41 and 0.14, respectively. However, digestion of 517bp fragment of CYP19 gene by DraI endonuclease determined two AG and AA genotypes with frequency 0.89 and 0.11, respectively. The Chi-square test proved that the two loci were in Hardy-Weinberg equilibrium (HWE). The significant effect was observed between different genotypes of MTNR1A gene and morphological trait (P<0.05) and there was a significant association between different genotypes of CYP19 gene and scrotal circumference trait (P<0.05). The results of this study indicated that polymorphisms of MTNR1A and CYP19 genes were not associated with most traits of sperm quality and testicular sizes. Therefore, it seems that further studies are needed to identify mutations in other regions of these genes and other genes responsible to genomic regions for the sperm quality and testicular size in Sanjabi ram in order to improve fertility in these herds.

Open access

Ali Sharghi, Hassanali Naghdi Badi, Sahebali Bolandnazar, Ali Mehrafarin and Mohammad Reza Sarikhani

Abstract

Fenugreek (Trigonella foenum-graecum L.) is a valuable medicinal plant, which is widely distributed throughout the world. It has been known that plant growth promoting rhizobacteria (PGPR) have positive effects on the quality and quantity of medicinal plants under different soil water levels. For this reason, a factorial experiment was conducted on the basis of a randomized complete block design (RCBD) to evaluate PGPR effects on the morphophysiological and phytochemical traits of fenugreek under different soil water levels. This study was conducted in two separate experiments: after the six-leaf stage and after the flowering stage. In the experiments, the treatments were plant growth promoting rhizobacteria (PGPR) including the control, Sinorhizobium meliloti, Pseudomonas fluorescens, a combination of S. meliloti and P. fluorescens, and different soil water levels (i.e. 100, 80, 60 and 40% of field capacity (FC) in three replications. The results showed that the highest seed weight per plant was obtained by inoculation with the S. meliloti and P. fluorescens combination at 100% FC after the two developmental stages. The maximum concentrations of nicotinic acid and trigonelline were observed for the combination of S. meliloti and P. fluorescens at the soil water content of 40% FC after the six-leaf stage and for S. meliloti at the soil water content of 40% FC after the flowering stage. The correlation and stepwise regression analyses showed positive effects of PGPR application on the morphophysiological and phytochemical traits of fenugreek plants under different soil water levels.

Open access

Ewa Tomaszewska, Siemowit Muszyński, Piotr Dobrowolski, Anna Winiarska-Mieczan, Małgorzata Kwiecień, Agnieszka Tomczyk-Warunek, Marta Ejtel, Izabela Świetlicka and Bożena Gładyszewska

Abstract

Lead (Pb) and cadmium (Cd) are toxic metals occurring commonly in the human environment that show mutagenic, genotoxic and carcinogenic effects. Dietary components could prevent heavy metals intoxication by reducing their accumulation in the body. The purpose of the study was to check possible protective effect of regular consumption of white, black, red, or green tea on bone metabolism during long-term exposure to Pb and Cd in adult rats. The 12 weeks-long exposure to Pb and Cd (50 mg Pb and 7 mg Cd/kg of the diet) in a rat model was studied. 12-week old adult male Wistar rats were randomly divided into a negative control group (Pb and Cd exposure without tea), a control (without Pb and Cd and teas), and groups co-exposed to Pb and Cd and supplemented with green, red, black, or white tea (n=12 each group). The experiment lasted for 12 weeks. The co-exposure to Pb and Cd led to the increase of bone resorption depending on the tea treatment, which was confirmed by the mechanical testing and histomorphometrical examination of cancellous bone. Pb and Cd influenced mechanical strength, reduced the densitometric and geometric parameters and the thickness of growth plate and articular cartilages. Concluding, white tea exerted the best protective effect on bone tissue and hyaline cartilage against heavy metal action.

Open access

Yasin Baykalir and Ulku Gulcihan Simsek

Abstract

This study was conducted to investigate the performance of laying hens and to determine possible age-related changes on external and internal quality traits of their eggs and synthesis of Heat Shock Protein 70 kDa (HSP70) in the conventional cage and organic rearing systems. For this purpose, 4 different Bovans White hybrid flocks of the same age were monitored in each of these two systems for 52 weeks. While a total of 360 eggs were examined to determine the effects of rearing system and age (30th and 60th weeks) on egg quality traits, 48 liver tissue samples were examined for the analysis of HSP70. Egg production (hen-day) and dirty egg ratio were higher in the organic rearing system (P<0.05). The age at 50% yield, the age at peak of lay, and peak production rate were calculated as 156, 218.75 days and 95.98% in the conventional system, and 155.75, 201.50 days, and 96.56% in the organic system, respectively (P>0.05). While egg weight, albumen weight, yolk weight, shell weight, shape index, and yolk colour were higher in the organic system, the crude ash ratio of eggshell and shell ratio were higher in the conventional system (P<0.05). It was also found that the egg weight, albumen weight, yolk weight, shell weight, and the percentage of yolk were higher at 60 weeks of age (P<0.001). The percentage of shell and albumen, shape index, and yolk colour were higher at 30 weeks of age (P<0.001). The interactions between rearing system and age were statistically significant in terms of shell thickness, shape index, crude ash ratio, and yolk colour (P<0.001). Stress protein (HSP70) level was affected only by the rearing system and was higher in the organic system (P<0.001). As a result, the organic system can be considered as advantageous in terms of egg production and quality traits and the eggs of young hens exhibited better properties. The high level of HSP70 in the organic system could indicate that hens were affected by the environmental conditions at higher rates and/or the hens reared in the organic system had a stronger antioxidant defence system.

Open access

Kholoud Khachlouf, Houda Hamed, Radhouane Gdoura and Ahmed Gargouri

Abstract

In recent years, the use of both natural and synthetic Zeolites in livestock feeds fed to lactating cows has increased, mainly to improve their performance, health, and to protect against mycotoxins intoxication. A compiled data of scientific literature was performed to analyze the effects of the incorporation of non-nutritional adsorbent Zeolite on production performance and ruminal environment parameters of lactating cows. At moderate levels (200-400 g/cow/day), milk yield was increased by Zeolite. Milk fat and protein contents and DMI were not altered and all ruminal parameters were improved: acetate was enhanced, propionate was reduced and consequently, acetate to propionate ratio was increased. The rumen pH was increased and rumen ammonia nitrogen was reduced. When the level of Zeolite exceeds 400 g/d/cow, all production and ruminal parameters were negatively altered. These data suggest that Zeolite level in the diet has a significant effect on the response of dairy production and ruminal environment characteristics.

Open access

Ilze Rutkovska and Ruta Medne

Abstract

Triiodothyronine and thyroxine levels and morphological parameters of fish were studied from January to May to evaluate the smoltification of yearling sea trout (Salmo trutta L.) raised in two different rearing systems (recirculating and flow-through) in three different hatcheries in Latvia. Thyroid hormone levels increased from January to May in both rearing systems in fish of different sizes. There was positive correlation between the degree of silvering and fish fork length and thyroid hormone levels, but there was no correlation between condition facor and thyroid hormone levels. Fish reared in recirculating systems were significantly larger (p < 0.05) and exhibited more visible signs of smoltification earlier than those reared in flow-through systems. The thyroid hormone levels and degree of silvering gradually became nearly the same by May in the sea trout from both rearing systems. Changes in thyroid hormone levels or fish size in spring cannot be evaluated separately from other signs to determine smoltification.

Open access

Grażyna Topolska, Anna Gajda and Urszula Imińska

Summary

Estimations of honeybee colony winter losses in Poland have been carried out at Warsaw University of Life Sciences since 2008 (in 2008 they concerned the two winters of 2006/07 and 2007/08), using a preliminary questionnaire in 2008 and the standardized COLOSS questionnaire since 2009. During the first years of the survey, concerning the period of autumn 2006 - spring 2012, the multimode method of data collection was used, and beekeepers sent in between 393 and 769 questionnaires a year. Overall, the number of participants increased, but in particular voivodeships it fluctuated. The estimated overall winter colony loss in Poland was low during the winter of 2006/07 (10%) and quite low during the winter of 2008/09 (11.5%). In other years it was substantially higher reaching 15.2% in 2007/08, 14.8% 2009/10, as much as 18.3% in 2010/11 and then down to 15.8% in 2011/12. A similar pattern of average losses was observed, but each year, excluding the winter of 2010/11, at least 50% of beekeepers reported acceptable losses of only up to 10%. During the analysis of the spatial pattern of overall losses, some data which could blur the pattern were eliminated. The results suggest that such climatic factors as a warm autumn but also high summer precipitation, followed by low winter temperatures influenced the spatial distribution of the losses.

Open access

Yu. M. Marusik and N. Larsen

Abstract

Until this study, Metellina Chamberlin et Ivie, 1941 was unknown in Africa and adjacent islands. A survey of the literature revealed that among nine species of Meta C. L. Koch, 1836 described from the region, two were misplaced in Metainae and actually belong to Tetragnatha Latreille, 1804: T. maculata Blackwall, 1865 (originally placed in the genus Tetragnatha) and Tetragnatha vacillans (Butler, 1876), comb. n. Meta meruensis Tullgren, 1910 misplaced in this genus, most likely belongs to Leucauge White, 1841 or a related genus. Six species are transferred from Meta, and new combinations are established for them: Metellina barreti (Kulczyński, 1899), comb. n., M. gertschi (Lessert, 1938), comb. n., M. longipalpis (Pavesi, 1883), comb. n., M. merianopsis (Tullgren, 1910), comb. n., M. minima (Denis, 1953), comb. n. and M. villiersi (Denis, 1955), comb. n. Metellina haddadi sp. n. is described from the foothills of the Table Mountain near Cape Town. The distribution of all species treated in this paper is mapped.

Open access

Krystyna Pohorecka, Andrzej Bober, Marta Skubida and Dagmara Zdańska

Abstract

The objective of the research was a comparative assessment of the infection levels of Nosema spp. in honey bees collected from different areas of the hive. A total of 588 honey bee colonies were sampled in spring (April-May) 2015 and 2016 through the simultaneous collection of dead worker bees from the bottom board of the hive and live bees from peripheral combs. A microscopic assay of composite samples of 60 bees was used for the detection and quantification of Nosema spp. spores. Consistent positive results of laboratory tests (detection of Nosema spp. spores in both live and dead bee samples) were achieved for 28% of colonies from surveyed group. In 36% of colonies both types of samples were Nosema-negative. Spores of Nosema spp. were detected solely in worker bees from the bottom board or exclusively in bees from nests in every 18% of sampled colonies. No differences were found between the share of colonies that had been identified as Nosema-infected on the basis of an analysis of only the live or dead bees (46% versus 46%). Laboratory examination of both types of bee samples can improve the reliability and accuracy of spore counting for the diagnosis of Nosema spp. infection in spring. The introduction of this sampling strategy in routine laboratory diagnostics can be considered as an alternative to the application of more sensitive PCR methods or sampling a higher number of live bees.

Open access

Walerij Isidorow, Stanisław Witkowski, Piotr Iwaniuk, Monika Zambrzycka and Izabela Swiecicka

Abstract

Honey is valued for its therapeutic qualities which are attributed among others to its antibacterial multifactorial properties. However, all the factors that influence these properties have not been identified. The present study is focused on the antibacterial action of fatty acids originating from royal jelly, the larval food of honeybees. Aliphatic C8-C12 acids characteristic of this bee product had previously been identified in more than fifty different samples of honey originating from seven countries and in eleven samples of Polish herbhoney. Experiments were performed to ascertain the influence of acidity on the antimicrobial activity of the acids. In acidic nutrient media all tested aliphatic hydroxyacids and unsaturated dicarboxylic acids demonstrated antibacterial action against different microbes with minimal inhibitory concentrations between 0.048 and 3.125 mM. Our results confirm that part of the antibacterial activity of honey contributes to these compounds of bee origin.