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  • Az évszak és az azonos évszakban történt ismételt mintavételek hatása holstein tenyészbikák ejakulátumának minőségi- és mennyiségi jellemzőire
    33-37
    Views:
    80

    This study was carried out at the Hungarian National Artificial Insemination Centre in order to evaluate the seasonal effects on the quantitative and qualitative parameters of sperm production using sperm analyser equipment. The volume of ejaculate (VE), percentage of living sperm (PLS), spermatozoa concentration (SC), motility score (MC), percentage of motile spermatozoa (PMS), speed of movement of sperm cells (SMS) and the percentage of sperm cells moving straightforward (PSMS) were collected and observed in three seasons (summer, autumn, winter) in Holstein-Friesian breeding bulls (n = 15). The sperm collection was done for three successive weeks in every season on the same day (summer: n = 41, autumn: n=39, winter: n = 42, altogether: n = 122). The same sperm samples were measured by sperm analyser equipment (HTM version 7.0, Danvers) for PMS, SMS and PSMS. The seasonal and the number of sperm collection effects were confirmed on semen characteristics by multiple analysis of variance (two ways MANOVA, Type III) using the program package of STATISTICA 4.5. The average values of VE were similar in the three seasons (summer: from 4.42 to 6.28 cm3, autumn: from 4.08 to 6.86 cm3, winter: from 5.43 to 5.71 cm3). The average values of the MC were similar in each of the three seasons (summer: from 3.66-4.00 M; autumn: from 3.66-3.77 M; winter: from 3.86-4.07 M). The summary of all effects for season (P<0.001), repeated sperm collections in the same season (P<0.05) and interaction of two traits (P<0.01) were established on the measured characteristics. The special effects (P<0.05) of a given season were calculated, excepting the VE and MC, on all of the measured characteristics. The special effect (P<0.01) of the repeated sperm collections in the same season was verified in only one case (SMS). It is not surprised at the interaction was established on the VE (P<0.001), PMS (P<0.05), and SMS (P<10.0). The results of present study suggest that seasonal effect on sperm quality of breeding bulls cannot be eliminated even at standard feeding and keeping conditions. Considering our results, we can recommend that the average values of three successive weeks in every season be used, to take advantage of seasonal effect on the quantitative and qualitative parameters of sperm production.

  • Seasonal changes of photosynthetical parameters as a results of forest gap model
    133-136
    Views:
    131

    Photosynthetic parameters of English oak (Quercus robur L.) as a member of Querco robori-Carpinetum were investigated in two different habitat in terms of gap forest management: in the gap and in the host forest. The artifical opening process of the forest resulted in more light for growing saplings and need for acclimatization. Photosynthesis is one of the most important way for plant life and plant production. In the centre of photosynthetic efficiency the quality and quantity traits of photosynthetic pigments are standing. During our work some photosynthetic parameters of plants (in the gap and in the forest as well) were measured: relative chlorophyll content as SPAD index, chlorophyll a and b content, total chlorophyll content and ratio of chlorophyll a and b. Based on our results no significant differences among our data in early spring. Although, during the summer significant differences occurred between the measured values in the gap and in the forest area. Lower total chlorophyll content was experienced in the gap, than in the forest area due to the lower chlorophyll-b content. Because of the high light intensity higher chla/chlb ratio was measured in the gap. The lower chlorophyll contents of gap habitat may have a part of the acclimatization process of photosynthetic apparatus against high light stress, which can determinate the survival chance of individual.

  • Stress Response of four Common Carp (Cyprinus carpio L.) Varieties with Different Genetic Background
    26-29
    Views:
    68

    Four different carp varieties were tested for stress reaction, with the help of 10 °C cooling and 100 g/l crowding. The selected varieties represented a broad genetic spectrum of carp species. The stress was monitored by measuring plasma cortisol, glucose and lysozim levels. In each test different varieties showed significantly different reaction to stress. This means that they differ in the trait of general resistance. Thus, this trait can be used in selection programmes and the acquired information helps to understand fish-environment interaction and specific resistance. These traits should be used in selection to improve the breeding of new more tolerant species for intensive farming or for organic production.

  • Comparative analysis on the fertiliser responses of Martonvásár maize hybrids in long-term experiments
    111-117
    Views:
    68

    The results of experiments carried out in the Agricultural Research Institute of the Hungarian Academy of Sciences clearly show that in the case of hybrids grown in a monoculture greater fertiliser responses can be achieved with increasing rates of N fertiliser than in crop rotations. In the monoculture experiment the parameters investigated reached their maximum values at a rate of 240 kg/ha N fertiliser, with the exception of 1000-kernel mass and starch content. In both cases the starch content was highest in the untreated control, gradually declining as the N rates increased. Among the parameters recorded in the crop rotation, the values of the dry grain yield, the 1000-kernel mass, the protein yield and the starch yield were greatest at the 160 kg/ha N fertiliser rate, exhibiting a decrease at 240 kg/ha. Maximum values for the protein content and SPAD index were recorded at the highest N rate. It is important to note, however, that although the N treatments caused significant differences compared to the untreated control, the differences between the N treatments were not significant.
    In the given experimental year the values achieved for the untreated control in the crop rotation could only be achieved in the monoculture experiment at a fertiliser rate of 160 kg/ha N, indicating that N fertiliser rates could be reduced using a satisfactory crop sequence, which could be beneficial from the point of view of environmental pollution, crop protection and cost reduction.
    The weather in 2006 was favourable for maize production, allowing comparative analysis to be made of the genetically determined traits of the hybrids. Among the three hybrids grown in the monoculture experiment, Maraton produced the best yield, giving maximum values of the parameters tested at a fertiliser rate of 240 kg/ha N. The poorest results were recorded for Mv 277, which could be attributed to the fact that the hybrid belongs to the FAO 200 maturity group, while the other hybrids had higher FAO numbers. Maraton also gave the highest yields in the crop rotation experiment at the 160 kg/ha N level. All three hybrids were found to make excellent use of the natural nutrient content of the soil.
    It was proved that the protein content of maize hybrids can only be slightly improved by N fertilisation, as this trait is genetically coded, while the starch content depends to the greatest extent on the ecological factors experienced during the growing season.

  • Survival analysis of sow longevity and lifetime reproductive performance – Review
    75-80
    Views:
    251

    Sow longevity plays an important role in economically efficient piglet production. Improving sow longevity results increase in the productivity and profitability of a sow herd. Longevity is a complex trait with many factors that can contribute to a sow having a long and productive life. Not only the sow’s genetics, but also nutrition, environment and the management policies are important. In addition, the removal of non-productive sows along with the introduction of replacement gilts is an essential part of maintaining herd productivity at a constantly high level. The objective of this paper was to summarize the current knowledge about the sow longevity and lifetime performance values, as well as, discusses the survival analysis methods for sow longevity traits. This method can estimate the hazard rate indicating proportional risk of sows being culled at any given time, in addition, it is able to investigate the effects of different factors on longevity. Identifying factors that influence the longevity could assist many commercial pig producers in becoming more efficient.