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Open access

Hoda Javaheri Barfourooshi, Armin Towhidi, Hassan Sadeghipanah, Mehdi Zhandi, Saeed Zeinoaldini, Essa Dirandeh and Robert M. Akers

Abstract

The aim of this study was to evaluate the effect of feeding oil supplement on mammary gland development and milk production responses in Holstein cows. Ten multiparous Holstein cows (42.2±9.2 d before calving, 3.25±0.25 body condition score, and 620±35 kg body weight) were randomly assigned to treatments. Treatments were a diet with oil added as palm oil (PO; n=5), or fish oil (FO; n=5) given to cows until 63 d in milk. Milk yield was recorded daily, milk composition (fat, protein, lactose, total solid and somatic cell count) was measured weekly and fatty acid profiles of milk fat were determined at first and last week of the experiment. Samples of mammary tissue were obtained at 7 and 63 d in milk by biopsy gun. Tissue slides were analyzed by Image J software. Results showed that fish oil supplemented diet compared to the palm oil supplemented diet increased milk production after 6 weeks of lactation (P<0.05), content of polyunsaturated fatty acids milk fat (P<0.05) and docosahexaenoic acid (P<0.01). Moreover, n-6:n-3 ratio was decreased by fish oil supplement (P<0.05). Histological studies showed that FO increased the relative percentage of tissue area occupied by epithelial cells as well as a number of total alveoli in each microscopic field (P<0.05). Data suggested that feeding fish oil during the dry period and early lactation could improve development and function of the mammary gland in the dairy cow.

Open access

S. Peter, B. Manojkumar, D. Pillai, A. Velusamy, B. Kamarudeen, P. Sreeparvathy and F. Agnes

Abstract

An attempt was made out to study the distribution and diversity of gelatinous zooplankton in the South Eastern Arabian Sea in the region Kanyakumari to off Kollam. A total of 19 species belonging to 8 groups such as chaetognaths, siphonophores, Hydrozoa and Scyphozoa of the phylum Cnidaria, ctenophores, appendicularians, doliolids and salps were recorded. Chaetognaths were not only predominant group, but also the most numerous. Sagitta enfl ata was the most widely distributed chaetognath species from most of the stations studied. Th e siphonophores were the second most abundant group. Shannon-Weaver species diversity index (H′), Margalef’s species diversity index (D) and Pielou’s species evenness (J′) of gelatinous zooplankton were found to be higher from the off shore, Kollam (Station 10) and minimum from the inshore, the Kanyakumari (Cape) West (Station 1). Diversity of gelatinous zooplankton was found to be positively correlated with atmospheric temperature, sea surface temperature and pH. A continuous seasonal study should be conducted to understand the clear impact of physical and chemical factors on the distribution and diversity of gelatinous zooplankton along this region.

Open access

Iwona Radkowska, Eugeniusz Herbut and Adam Radkowski

Abstract

The aim of the study was to determine the yield and chemical composition of milk from TMR-(group I) and pasture-fed Simmental cows (group II). The study was conducted with second and third lactation Simmental cows between 30 and 200 days of lactation. The present research showed that compared to TMR feeding, the use of summer pasture feeding and proper supplementation with high-energy feeds allow for higher milk yield and higher nutritive value of the milk. Compared to TMR-fed cows (group I), milk from pastured cows (group II) was characterized by a more beneficial composition of protein fractions, and a higher content of α-lactalbumin, β-lactoglobulin and lactoferrin. It also contained more vitamins A and E, calcium, magnesium and iodine, and had a significantly (P≤0.05) lower cholesterol content. The milk of cows from group II contained over twice as much CLA (1.59% of all acids) and 35% more n-3 PUFA, which resulted in a more beneficial n-6/n-3 fatty acids ratio of 2.88. In addition, this milk contained significantly (P≤0.05) less saturated fatty acids (SFA) and significantly more (P≤0.05) mono-(MUFA) and polyunsaturated fatty acids (PUFA). Consequently, the MUFA:SFA and PUFA:SFA ratios in this group were more favourable at 0.448 and 0.066, respectively. Also the content of desirable fatty acids (DFA) with hypocholesterolemic effects was higher in group II, which resulted in a more beneficial DFA:OFA ratio of 0.8 in this group. In conclusion, the use of summer pasture feeding and a proper supplemented feeding ration in Simmental cows with high-energy feeds allow for high milk yield and high nutritive value of the milk.

Open access

Magdalena Hryhorowicz, Joanna Zeyland, Agnieszka Nowak-Terpiłowska, Jacek Jura, Wojciech Juzwa, Ryszard Słomski, Jan Bocianowski, Zdzisław Smorąg, Anna Woźniak and Daniel Lipiński

Abstract

The use of pigs as a source of organs and tissues for xenotransplantation can overcome the growing shortage of human donors. Human NK cells play an important role in the cell-mediated rejection of pig-to-human xenografts. In this paper we report the generation and extensive characterization of three generations of transgenic pigs with HLA-E gene encoding the antigen which can inhibit the human NK cell-mediated response. The gene construct pHLAE-GFPBsd containing the human gene encoding the human leukocyte antigen under the promoter of the EF-1α elongation factor ensuring systemic expression was introduced by microinjection into a pronucleus of the fertilized porcine oocyte. PCR analysis revealed and FISH analysis confirmed that the pHLAE-GFPBsd gene construct was present in the genome of the founder female pig. As a result of inter-breeding, an additional 7 transgenic animals were obtained (one individual from F1 generation and six individuals from F2 generation). The transgene expression was shown by RT-PCR and flow cytometry. Real Time PCR analysis estimated the approximate number of transgene copies at 16–34. Karyotype analysis did not show any changes in the structure or the number of chromosomes. The expression level of the transgene was stable in the next generation of genetically modified pigs. An NK cell-mediated cytotoxicity assay showed the increased viability of the transgenic cells in comparison with the wild-type, which confirmed the protective influence of HLA-E expression.

Open access

Ewelina Semik-Gurgul, Tomek Ząbek, Agnieszka Fornal, Artur Gurgul, Klaudia Pawlina-Tyszko, Jolanta Klukowska-Rötzler and Monika Bugno-Poniewierska

Abstract

In the recent years, particular attention was given to the research aimed at optimizing the use of tumour epigenetic markers. One of the best known epigenetic changes associated with the process of carcinogenesis is aberrant DNA methylation. The aim of the present research was to evaluate the methylation profile of genes potentially important in the diagnosis and/or prognosis of equine sarcoids, the most commonly detected skin tumours in Equidae. The methylation status of potential promoter sequences of nine genes: APC, CCND2, CDKN2B, DCC, RARβ, RASSF1, RASSF5, THBS1 and TRPM1, was determined using bisulfite sequencing polymerase chain reaction (BSP-CR). The results of this study did not reveal any changes in the level of DNA methylation in the analysed group of candidate genes between the tumour and healthy tissues. Despite numerous reports describing the aberrant methylation of the promoters of the analysed genes in human cancers, the data obtained did not confirm the existence of such relationships in the examined tumour tissues, which excludes the possibility of using these genes for the diagnosis of the equine sarcoid.

Open access

Krzysztof Adamczyk, Wojciech Jagusiak and Joanna Makulska

Abstract

The effect of crossbreeding Holstein-Friesian cows with other breeds is usually improved genetic potential of crossbreds in terms of longevity. However, culling decisions, which in practice determine the longevity in dairy cows, are contingent on many environmental and economic factors. Therefore, the aim of this study was to evaluate longevity in relation to culling reasons in Holstein-Friesian cows of the Black-and-White strain (HO) and crossbreds, taking genotype, age at first calving, herd size, culling season, culling reason and milking temperament into consideration. The data analysed concerned 154,256 dairy cows culled in Poland in 2015. It was found that all studied factors significantly affected cow lifetime performance. The mean age at culling in dairy cows of HO strain exceeded 6 years, with mean lifetime energy-corrected milk (LECM) yield of 28,933 kg and mean lifetime energy-corrected milk yield per milking day (DECM) of 20.2 kg. Crossbreds, on the other hand, tended to have shorter lifespans, with mean LECM yield amounting to less than 25,000 kg. Mean LECM yield of cows surviving for the longest period (9.2 years), amounted to 47,771 kg, and reproduction problems were unquestionably the most common (40%) reason for cows’ culling. A suggestion was made to take milking temperament into account in breeding practice, as this trait proves to be closely related to the longevity characteristics of dairy cows. It was also proposed that the culling reasons be subjected to a more comprehensive analysis, considering the “life history” of cows as well as the interactions between different reasons for their removal from the herd.

Open access

Eugeniusz Herbut, Ewa Sosnówka-Czajka and Iwona Skomorucha

Abstract

Research has shown that microclimate is determined not only by air microparticles, but also by the degree of air ionization. Ions affect the body through the respiratory tract and skin. Exposure of reared chickens to elevated air temperature (37°C–23°C) was found to accelerate the break-down of negative ions compared to temperature lower by 10°C. Negative air ionization offsets the adverse effect of elevated temperature on chickens. Higher (85%) air humidity during rearing of chickens was also observed to destroy negative ions. Research findings indicate that air ionization is an environmental element that contributes to improving performance in broiler chickens. Many studies have also confirmed a positive effect of air ionization on the body weight and health of piglets.

Open access

V. Vetvicka and R. Fernandez-Botran

Summary

Immunosuppression caused by parasitic infections represents the foremost way by which the parasites overcome or escape the host’s immune response. Glucan is a well-established natural immunomodulator with the ability to significantly improve immune system, from innate immunity to both branches of specific immunity. Our review is focused on the possible role of glucan’s action in antiparasite therapies and vaccine strategies. We concluded that the established action of glucan opens a new window in treatment and protection against parasitic infections.

Open access

Oleksandr S. Potrokhov, Oleg G. Zinkovskyi, Mykola V. Prychepa and Yuryi M. Khudiyash

Abstract

Changes in the activity of Na+/K+-ATPase, lactate dehydrogenase, and succinate dehydrogenase in the white muscles and gill petals of roach, Rutilus rutilus (L), were studied for the combined actions of water mineralization and water temperature. It was established that decreased mineralization to 260.0 mg dm-3 and increased water temperature to 32°C increased aerobic processes in roach tissues. A sharp increase in water temperature and changes in water mineralization significantly affected the tolerance and physiological state of fish and could impact their abundance in waterbodies.

Open access

Lidia Dzierzbicka-Głowacka, Artur Nowicki, Maciej Janecki, Beata Szymczycha, Piotr Piotrowski, Piotr Pieckiel and Grzegorz Łukasiewicz

Abstract

As consumer awareness increases in Poland, fish consumption is on an upward trend. While new technologies permit meeting increasing demand, they significantly increase the pressure on fish supplies. As a result, many fish stocks are over-exploited, which threatens marine ecosystems. Declining fisheries, increasing fishing operating costs, and the necessity of making longer fishing expeditions at greater distances that often end with catches of fewer or less valuable fish mean that in some fisheries sectors are currently running at the margins of profit or at a loss. At the same time, the European Union’s fisheries policy aims to create more selective and sustainable fisheries, to implement limitations through fishing quotas, and to ban the recognition of discards. The aim is to ensure that individual fish species are protected while providing the European Union with stable, secure supplies of fresh fish. The FindFish Knowledge Transfer Platform project was launched to provide solutions for challenges facing commercial fisheries. Its purpose is to provide fishers with a knowledge transfer platform and a numerical forecasting system for the marine environment of the Gulf of Gdansk. By combining in-situ research, environmental data, fish catch data, and numerical calculations, this tool will improve the accuracy of targeted fishing while reducing by-catch. The system will provide more reliable data on fish stocks and facilitate more efficient resource management.