The Bulk Specimen X-Ray Microanalysis of Freeze-Fractured, Freeze-Dried Tissues in Gerontological Research

The rationale for choosing the freeze-fracture freeze-drying (FFFD) method of biological bulk specimen preparation as well as the theoretical and practical problems of this method are treated. FFFD specimens are suitable for quantitative X-ray microanalysis of biologically relevant elements. Although the spatial resolution of this analytical technique is low, the application of properly selected bulk standard crystals as well as the measurement of the intracellular water and dry mass content by means of another method developed in the same laboratory, allow us to obtain useful information about the age-dependent changes of ionic composition in the main intracellular compartments. The paper summarizes the problems with regard to specimen preparation, beam penetration and the quantitative analysis of FFFD specimens. The method has been applied so far mainly for the analysis of intranuclear and intracytoplasmic concentrations of Na, Cl and K in various types of cells and has resulted in a significant contribution to our understanding of the cellular mechanisms of aging

A Review on the Use of Bulk Specimen X-Ray Microanalysis in Cancer Research

The freeze-fracture, freeze-drying ( FFFD) method of biological bulk specimen preparation combined with quantitative X-ray microanalysis is suitable for the measurement of intracellular concentrations of biologically relevant elements in human biopsy or experimental animal materials. Especially useful information can be obtained regarding the intracellular Na+/K+ ratios being independent of the actual (and unknown) water content of the cytoplasm. The sustained increase of this ratio indicates a sustained depolarization of the cell membrane. These data are of importance from the point of view of the membrane hypothesis of mitogenesis (MHM). It has been revealed that the distribution histograms of the intracellular Na+/K+ ratio display a very significant broadening and an increase of the average values in human urogenital, thyroid and laryngeal tumors, as well as in experimentally induced cell proliferation models. Although MHM has been claimed to be invalid on the basis of some atomic absorption measurements of the intracellular monovalent ion concentrations as well as of some in vitro results obtained with amiloride, this review paper demonstrates that MHM may still be a valid hypothesis for the explanation of mitotic regulation

Alterations of the Intracellular Water and Ion Concentrations in Brain and Liver Cells During Aging as Revealed by Energy Dispersive X-Ray Microanalysis of Bulk Specimens

Age dependence of the intracellular concentrations of monovalent ions (Na+, K+ and Cl-) was examined in 1, 11 and 25-month-old rat brain and liver cells by using energy dispersive X-ray microanalysis. The in vivo concentrations of Na+, K+ and Cl- ions were calculated from two different measurements: The elemental concentrations were measured in freeze-dried tissue pieces, and the intracellular water content was determined by means of a recently developed X-ray microanalytic method, using frozen-hydrated and fractured bulk specimens as well as subsequent freeze-drying. All the single monovalent ion concentrations and consequently, also the total monovalent ion content showed statistically significant increases during aging in brain cortical neurons. A 3-6% loss of the intracellular water content was accompanied by a 25-45% increase of the monovalent ionic strengths by the age of 25 months. A membrane protective OH radical scavenger (centrophenoxine) reversed the dehydration in the nerve cells of old animals, resulting in a decrease of the intracellular ion concentrations. Aging has a less prominent effect on the water and ion contents of the hepatocytes. The degree of water loss of cytoplasm exceeds that of the nuclei in the liver, suggesting that dominantly the translational steps can be involved in the general age altered slowing down of the protein synthetic machinery, predicted by the membrane hypothesis of aging (Zs.- Nagy, 1978)

Divergent selection for fat index in Pannon Ka rabbits: genetic parameters, selection response

[EN] The objective of this study was to estimate the response to selection for total body fat content of rabbits measured by computer tomography (CT). A divergent selection experiment was performed using Pannon Ka rabbits, which were previously selected for number of kits born alive. The so-called zero generation consisted of 351 Pannon Ka rabbits, from which the index, total body fat volume (cm3) divided by the body weight (kg), was measured. Rabbits with low and high fat index values were selected to form the parent groups of the lean and fat lines, respectively. The lines consisted of 55-72 females and 35-47 males, depending on the line and generation. After three generations, the rabbits were evaluated by means of a single trait animal model. The fat index showed a moderate heritability estimate (0.28±0.03). The magnitude of the common litter effect was small (0.10±0.02). The breeding values averaged per generation provided slightly asymmetrical responses. Based on the results, the divergent selection was successful in confirming that CT is a very suitable method for performing selection for body composition traits.EFOP-3.6.3-VEKOP-16-2017-00008 project. The project is co-financed by the European Union and the European Social Fund and the János Bolyai Research Scholarship of the Hungarian Academy of Sciences (BO/00871/19)Kasza, R.; Matics, Z.; Gerencsér, Z.; Donkó, T.; Radnai, I.; Szendrő, Z.; Nagy, I. (2020). Divergent selection for fat index in Pannon Ka rabbits: genetic parameters, selection response. World Rabbit Science. 28(3):129-133. https://doi.org/10.4995/wrs.2020.12733OJS129133283Al-Saef A.M., Khalil M.H., Al-Dobaib S.N., Al-Homidan A.H., García M.L., Baselga M. 2008. Comparing Saudi synthetic lines of rabbits with the founder breeds for carcass, lean composition and meat quality traits. Livest. Res. Rural Dev., 20: 1-12.Donkó T., Czakó B., Kovács Gy., Petneházy Ö., Kasza R., Szendrő Zs., Garamvölgyi R., Matics Zs. 2016. Total body fat content determination by means of computed tomography (CT) in rabbits. In: Proceedings of the 11th World Rabbit Congress, 16-18 June 2016, Qingdao, China, pp. 753-756.Fortun-Lamothe L. 2006. Energy balance and reproductive performance in rabbit does. Anim. Reprod. Sci., 93: 1-15. https://doi.org/10.1016/j.anireprosci.2005.06.009Garreau H., Eady S.J., Hurtaud J., Legarra A. 2008. Genetic parameters of production traits and resistance to digestive disorders in a commercial rabbit population. In: Xiccato G., Trocino A., Lukefahr S. (eds.) In Proc.: 9th World Rabbit Congress. Fondazione Iniziative Zooprofilattiche e Zootechniche, Verona, Italy, pp. 103-108.Falconer D.S., Mackay T.F.C. 1996. Introduction to Quantitative Genetics. 4th Ed. Longman, London, UK. 1-464.Garreau H., Larzul C., Tudela F., Ruesche J., Ducqrocq V., Fortun-Lamothe L. 2017. Energy balance and body reserves in rabbit females selected for longevity. World Rabbit Sci., 25: 205-213. https://doi.org/10.4995/wrs.2017.5216Groeneveld E. 1990. PEST Users' Manual. Institute of Animal Husbandry and Animal Behaviour Federal Research Centre, Neustadt, Germany 1-61.Groeneveld E., Kovac M., Mielenz N. 2008. VCE User's Guide and Reference manual. Version 6.0. Institute of Farm Animal Genetics, Neustadt, Germany, 1-125.Larzul C., de Rochambeau H. 2005. Selection for residual feed consumption in the rabbit. Livest. Prod. Sci., 95: 67-72. https://doi.org/10.1016/j.livprodsci.2004.12.007Larzul C., Gondret F., Combes S., de Rochambeau H. 2005. Divergent selection on 63-day body weight in the rabbit: response on growth, carcass and muscle traits. Genet. Sel. Evol., 37: 105-122. https://doi.org/10.1051/gse:2004038Martínez-Álvaro M., Hernández P., Blasco A. 2016. Divergent selection on intramuscular fat in rabbits: Responses to selection and genetic parameters. J. Anim. Sci., 94: 4993-5003. https://doi.org/10.2527/jas.2016-0590Matics Zs., Nagy I., Gerencsér Zs., Radnai I., Gyovai P., Donkó T., Dalle Zotte A., Curik I., Szendrő Zs. 2014. Pannon breeding program in rabbit at Kaposvár University. World Rabbit Sci., 22: 287-300. https://doi.org/10.4995/wrs.2014.1511Milisits G., Romvári R., Dalle Zotte A., Szendrő Zs. 1999. Non-invasive study of changes in body composition in rabbits during pregnancy using X-ray computerized tomography. Ann. Zootech., 48: 25-34. https://doi.org/10.1051/animres:19990103Nagy I., Ibáñez N., Mekkawy W., Metzger Sz., Horn P., Szendrő Zs. 2006. Genetic parameters of growth and in vivo computerized tomography based carcass traits in Pannon White rabbits. Livest. Sci., 104: 46-52. https://doi.org/10.1016/j.livsci.2006.03.009Romvári R., Milisits G., Szendrő Zs., Sørensen P. 1996. Non invasive method to study the body composition of rabbits by X-ray computerized tomography. World Rabbit Sci., 4: 219-224. https://doi.org/10.4995/wrs.1996.298Rouvier R. 1970. Variabilité génétique du rendement a l'abattage et de la composition anatomique de lapins de trois races. Ann Genet. Sel. Anim., 2: 325-346. https://doi.org/10.1186/1297-9686-2-3-325Shemeis A., Abdallah O.Y. 2000. Possibilities of developing favourable body fat partition via selection indexes - application on rabbits. Arch. Anim. Breed., 43: 193-202. https://doi.org/10.5194/aab-43-193-2000Szendrő Zs., Romvári R., Horn P., Radnai I., Bíró-Németh E., Milisits G. 1996. Two-way selection for carcass traits by computerised tomography. In: Proc. 6th World Rabbit Congress, Toulouse, 2, 371-375.Szendrő Zs., Metzger Sz., Nagy I., Szabó A., Petrási Zs., Donkó T., Horn P. 2012. Effect of divergent selection for the computer tomography measured thigh muscle volume on productive and carcass traits of growing rabbits. Livest. Sci., 149: 167-172. https://doi.org/10.1016/j.livsci.2012.07.011Zomeño C., Hernández P., Blasco A. 2013. Divergent selection for intramuscular fat content in rabbits. 1. Direct response to selection. J. Anim. Sci., 91: 4526-4531. https://doi.org/10.2527/jas.2013-636

Milk production of pseudopregnant multiparous does

The aim of the experiment was to evaluate the milk production of pseudopregnant does. In this experiment, data of multiparous, inseminated, pregnant (IP, n=15) does and two groups of presumably pseudopregnant multiparous does: inseminated, non-pregnant (INP, n=17) and induced to ovulation by GnRH (1.5 microgram per animal) at the day of insemination (11 d after parturition) (non-inseminated, ovulating: NIO, n=15) were analysed. The progesterone level was measured at the 12th d after treatment to determine if females were pseudopregnant. All IP and NIO does were pregnant and pseudopregnant, respectively. Within the INP group, 10 and 7 does were diagnosed as positive (INPO) or negative (INPNO) for pseudopregnancy. Two of the INPNO does perished during lactation. The average milk production of groups IP, INP and NIO was 212, 92 and 72 g/d, respectively (P160 g in the various groups were: IP=0, 0, 0, 0 and 100%, NIO=20, 13, 27, 40 and 0%, INP=15, 15, 15, 55 and 0%, respectively. The daily milk yield of the 5 INPNO does was 2, 6, 27, 84 and 139 g, respectively. These results demonstrated that multiparous empty does, pseudopregnant or non-pseudopregnant, can produce milk, but in lower quantities than multiparous does after kindling.Szendrö, Z.; Matics, Z.; Brecchia, G.; Theau-Clément, M.; Nagy, Z.; Princz, Z.; Biró-Németh, E.... (2010). Milk production of pseudopregnant multiparous does. World Rabbit Science. 18(2). doi:10.4995/WRS.2010.18.1018

Investigation of antinutritive components in Hungarian potato cultivars depending on production technology

We have investigated the Total Glycoalcaloid (TGA), nitrite, and nitrate contents of some Hungarian and foreign potato cultivars in relation to the effect of different combination of fertilisers and green manure, late blight management strategies (none, programmed, or prediction based spraying), and irrigation regime for three years. The Hungarian cultivars have exotic potato species like S. acaule, S. demissum, S. stoloniferum, S. vernei, or S. tub. ssp. andigenum in their genetic background as sources of resistance genes. No effect of fertilisers or irrigation was found on the level of glycoalkaloids and nitrate contents, which were influenced mostly by the genotype and season. In conclusion, the absolute amount and the presence of different antinutritive components of potato tubers were influenced by the technology, genotype, and season in a complex manner. These results in general prove that ware potato production utilising intensive commercial agrotechnical practices and common cultivars is safe regarding the nitrate and TGA content of tubers

Effect of group size and stocking density on productive, carcass, meat quality and aggression traits of growing rabbits

[EN] The aim of the experiment was to examine the effect of group size and stocking density on productive, carcass and meat quality traits. The trial was conducted using 230 Pannon white rabbits weaned at 5 weeks and reared until the age of 11 weeks. Seven groups were formed with different cage/pen sizes (group size) and stocking densities: SC16=small cage (0.12 m2), 16 rabbits/m2 (2 rabbits/cage); LC16=large cage (0.50 m2), 16 rabbits/m2 (8 rabbits/cage); LC12=large cage, 12 rabbits/m2 (6 rabbits/cage); SP16=small pen (0.86 m2), 16 rabbits/m2 (13 rabbits/cage); SP12=small pen, 12 rabbits/m2 (10 rabbits/cage); LP16=large pen (1.72 m2), 16 rabbits/m2 (26 rabbits/cage); LP12=large pen, 12 rabbits/m2 (20 rabbits/cage). Stocking density did not affect production significantly, as stocking densities lower than 16 rabbits/m2 had no effect on the growing rabbits¿ performance. Group size (size of the cage or pen) had an effect on certain growth, carcass and meat quality traits. Increasing group size resulted in lower values for weight gain (SC: 39.2>LC: 39.0> SP: 38.7> LP: 37.8 g/d; P=0.22) and body weight (SC: 2506>LC: 2498> SP: 2487> LP: 2446 g; P=0.35), similarly to other results in the literature, but the differences were not significant. Aggressive behaviour was observed to be more frequent in the larger group sizes. At the age of 11 weeks the proportion of rabbits with ear lesions in the SC, LC, SP and LP groups were 0.0, 7.1, 8.7, and 17.4%, respectively, demonstrating that larger group size increases the risk of ear lesions. The effect of group size on the ratio of the fore part to the reference carcass (SC: 28.5, LC: 28.2, LP: 29.0%; P=0.02) and on the amount of perirenal fat (SC: 21.3, LC: 18.0, LP: 13.7 g; P<0.001) was significant. Meat quality traits (dry matter, protein, fat and ash content, drip loss, pH, L*, a*, b* values) were not affected by group size (cage vs. pen), but successful discriminations were performed using the NIRS method.The authors gratefully acknowledge the financial assistance received from the GAK OMFB-01335/ALAP1- 00121 project.Szendrö, Z.; Princz, Z.; Romvári, R.; Locsmándi, L.; Szabó, A.; Bázár, G.; Radnai, I.... (2009). Effect of group size and stocking density on productive, carcass, meat quality and aggression traits of growing rabbits. World Rabbit Science. 17(3):153-162. https://doi.org/10.4995/wrs.2009.65515316217

Application of gnawing sticks in rabbit housing

[EN] Four experiments are described relating to gnawing sticks application in rabbit housing. In experiment 1 and 2, Pannon White rabbits, weaned at the age of five weeks, were placed into pens with wire net floor. In experiment 1, every pen (180 animals in 12 pens, surface per head: 571 cm2) was provided with three gnawing sticks randomly chosen from White locust, Black elder, White willow, Little-leaf linden, European larch, Black poplar, European white birch, White buckeye and White mulberry species. In experiment 2 (150 animals in 10 pens, surface per head: 571 cm2), only those tree species ingested by rabbits in the first experiment were used (White locust, White willow, Little-leaf linden, Black poplar and White buckeye). In the second experiment, rabbits showed the highest preference towards gnawing sticks of Little-leaf linden, while similar White willow and White buckeye consumption was observed. In the experiment 3, rabbits¿ preference to different types of wood and the influence on rabbits¿ behaviour of added wooden sticks as environmental enrichment was studied. At the age of 38 days, 48 male SIKA rabbits were housed individually in wire cages (surface per head: 1500 cm2). According to the type of wood placed in the cage, rabbits were equally allotted to four groups: control, Common oak, Little-leaf linden and Norway spruce. Rabbits¿ preference to type of wood was studied on all the animals with wooden stick, while rabbits¿ behaviour was studied on 16 focus animals at the age of 5 and 13 weeks using continuous 24 hours video recordings. Rabbits preferred gnawing Little-leaf linden and Norway spruce compared to Common oak. Addition of gnawing sticks had no significant influence on duration of rabbits¿ behaviour, except for eating feed and gnawing wooden stick time. In experiment 4, the effect of housing and environmental enrichment on the performance and behaviour of growing rabbits was tested. 72 hybrid rabbits were housed after the weaning period in standard fattening cages at 2, 3, 4 animals per cage (surface per head: 1045 cm2, 697 cm2, 522 cm2, respectively). Half cages were enriched using a wood stick (Robinia pseudoacacia) dangling from the ceiling of the cage. The environmental enrichment decreased the stereotypies (gnawing the bars of the cage). A tendency to lower aggressive behaviours in enriched caged rabbits was also found compared to the conventional caged rabbits. This might indicate a better satisfaction of the behavioural needs for the enriched caged rabbits.Princz, Z.; Orova, Z.; Nagy, I.; Jordan, D.; Stuhec, I.; Luzi, F.; Verga, M.... (2007). Application of gnawing sticks in rabbit housing. World Rabbit Science. 15(1):29-36. doi:10.4995/wrs.2007.607293615