Stress responses in adult cattle due to surgical dehorning using three different types of anaesthesia

Dehorning adult cattle is a surgical procedure causing distress of varying intensities that can be reflected in behavioural changes and alterations in plasma cortisol levels. Stress responses during the dehorning process were evaluated in 18 Red Pied cows. The cows were divided into 3 groups of six and kept in tie-stall housing. Those in the first group were dehorned under general anaesthesia (GA) induced by intravenous administration of xylazine and ketamine. The second group was dehorned under sedation and local anaesthesia (SLA) induced by intramuscular administration of xylazine and local anaesthesia with lidocaine. The third group was dehorned under local anaesthesia (LA) with lidocaine. Dehorning was performed with a foetotomy wire. Blood samples were taken 0.5 h before dehorning to determine cortisol levels, and, by means of a central venous catheter inserted into the jugular vein, during surgery at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7 and 8 h post-surgery. Concurrently, occurrence of stress behaviours was assessed. Cortisol levels were measured by enzyme immunoassay (EIA). The lowest mean peak levels of plasma cortisol (82.53 +/- 6.04 nmol l(-1)), the most rapid return of plasma cortisol levels to baseline values (1.92 +/- 1.11 h), and the lowest occurrence of stress behaviours (2.38 +/- 5.83%) were noted in the SLA group. The highest mean peak levels plasma cortisol (113.86 +/- 25.65 nmol l(-1)), the slowest return of plasma cortisol levels to baseline values (3.83 +/- 2.18 h) and the most frequent occurrence of stress behaviours (65.48 +/- 28.72%) were observed in the LA group. There were significant differences between the SLA and LA groups in peak plasma cortisol levels (p = 0.011) and in occurrence of stress behaviours (p = 0.003). Sedation induced by intramuscular administration of xylazine in conjunction with local anaesthesia with lidocaine is considered the most suitable method of anaesthesia when dehorning adult cattle. Local anaesthesia with lidocaine alone was least suitable.     

In vitro androgenesis of wheat: from fundamentals to practical application

Wheat anther cultures have a history of almost 30 years and are nowemployed efficiently in many countries of the world for the developmentof doubled haploid lines for breeding. The present paper discusses keyquestions of the elaboration and perfection of the method: cytologicalaspects of in vitro androgenesis, the conditions required for theembryogenic development of microspores and the applicability of anthercultures in the Martonvásár wheat breeding programme.     

The digestibility of milk substitutes with various soybean products in young calves

Digestibility trials were performed to study the suitability of mixtures made up of treated soybean and whey powder for replacing skim milk powder. Three different milk replacers were used, the replacers T-18/II and T-18/III containing Plyllac preparations manufactured by different technologies. When using the T-18 preparation with 18% fat content it was found that the protein source may contain 25% Plyllac preparation and 11% sweet whey powder. In two cases, at the age of 5 and 7 weeks, the digestibility of the crude protein in the T-18/II preparation was found to deteriorate significantly. For this reason, the authors suggest this milk replacer to be used from the 5th week of life. Trials were performed with 3 milk replacers (lactine preparations) containing Plyllac preparations of different manufacturing technology (35%), treated soybean (10%) and sweet whey powder (10%). It was found that the use of Plyllac preparations, i.e. of treated soybean in larger amounts causes the nutrient digestibility, mainly that of crude protein, to be significantly lower at the age of 3 and 5 weeks than that at the age of 7 to 9 weeks. No significant differences were found in the digestibility of the various Plyllac preparations manufactured by different technologies. The milk replacer lactine is recommended for use from the 5th week of life on.     

Breeding for breadmaking quality using old Hungarian wheat varieties

Due to their broad population diversity, old wheat varieties or landraces play an important role in increasing the genetic variability of agronomic traits. On these grounds, an analysis was made of the high molecular weight (HMW) glutenin subunit composition of the old Hungarian wheat variety Bánkúti 1201. It was found that several genotypes with differing breadmaking qualities can be distinguished for this character. When using old varieties in breeding, it is possible to broaden the genetic background of characters responsible for breadmaking quality by separating the populations. A more detailed analysis of the protein composition of germplasm created in this way will be required to obtain a better understanding of this complex character for its conscious introduction into breeding programmes. This revised version was published online in August 2006 with corrections to the Cover Date.     

Molecular markers for the identification of resistance genes and marker-assisted selection in breeding wheat for leaf rust resistance

The resistance genes Lr9, Lr24, Lr25, Lr29, Lr35 and Lr37, which were not previously utilised in Hungary, have been incorporated into four Martonvásár winter wheat cultivars using marker-assisted selection with PCR-based markers. In the course of a backcross programme, the genes were transferred into Martonvásár wheat varieties and various BC generations were produced. Work aimed at pyramiding resistance genes is currently underway in Martonvásár, and plants containing the gene combinations Lr9 + Lr24, Lr9 + Lr25 and Lr9 + Lr29 are now available. From the BC₂F₄ generation of the ‘Mv Emma’*3/’R.L.6010’ combination (‘R.L.6010’ is the donor of the Lr9 gene) 287 lines were tested for leaf rust resistance in an artificially inoculated nursery. A co-dominant primer combination was designed to identify both resistant and susceptible offsprings. The results of resistance tests and molecular marker detection agreed in most cases. Designated leaf rust resistance genes were identified with molecular markers in wheat varieties and breeding lines. The Lr26 and Lr34 resistance genes occur frequently in the Martonvásár gene pool, and the presence of the Lr37 gene has also been detected in a number of Hungarian genotypes.     

Postprandial glycemia, insulinemia, and satiety responses in healthy subjects after whole grain rye bread made from different rye varieties. 1

Rye products typically induce low insulin responses and appear to facilitate glucose regulation. The objective of this study was to investigate differences in postprandial glucose, insulin, and satiety responses between breads made from five rye varieties. Breads made from whole grain rye (Amilo, Rekrut, Dankowski Zlote, Nikita, and Haute Loire Pop) or a white wheat bread (WWB) were tested in a randomized cross-over design in 14 healthy subjects (50 g available starch). Metabolic responses were also related to the composition of dietary fiber and bioactive compounds in the breads and to the rate of in vitro starch hydrolysis. The Amilo and Rekrut rye breads induced significantly lower insulin indices (II) than WWB. Low early postprandial glucose and insulin responses (tAUC 0-60 min) were related to higher amounts of caffeic, ferulic, sinapic, and vanillic acids in the rye breads, indicating that the phenolic acids in rye may influence glycemic regulation. All rye breads induced significantly higher subjective feelings of fullness compared to WWB. A low II was related to a higher feeling of fullness and a lower desire to eat in the late postprandial phase (180 min). The data indicate that some rye varieties may be more insulin-saving than others, possibly due to differences in dietary fiber, rate of starch hydrolysis, and bioactive components such as phenolic acids.     

Blood glutathione peroxidase enzyme activity as an index of selenium release from Permasel in ewes.

Ten Merino ewes were given a single Permasel pellet (containing 5% of elementary selenium) orally and examined for the release of selenium in the reticulum by determining glutathione enzyme activity of the whole blood haemolysate over a period of 12 months. As compared to the controls, the treated ewes exhibited a significant elevation in glutathione peroxidase activity for 8 months, indicating an acceptable persistence of the product tested.     

Relationship between anther culture response and aluminium tolerance in wheat (Triticum aestivum L.)

A combination of in vivo and in vitro selection methods were used to increase aluminium tolerance in wheat using wheat x triticale crosses. Both in vivo and in vitro aluminium treatments significantly influenced the anther culture response. In vivo selection at the seedling stage resulted in significantly higher embryo induction. On induction media containing aluminium, the embryoid induction frequency dropped significantly, but there was an increase in the green plant regeneration frequency. In spite of this effect, all doubled haploid (DH) lines were more tolerant to aluminium in seedling tests than the winter wheat parent. The application of in vivo aluminium selection, before the start of anther culture, increased the probability of obtaining DH lines with significantly higher tolerance, compared to the original population. After three selection cycles of the original populations, there was a significant difference in the root regrowth rate of tolerant and sensitive plants. Both sensitive and tolerant plants showed a decrease due to the presence of aluminium in the induction media, with a greater decrease occurring in sensitive plants. Correlation between the rate of root regrowth in the seedling test and the change in embryo induction was positive, but moderate, emphasising the fact that plants with higher root regrowth tended to be more tolerant of the presence of aluminium in the induction medium. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effect of milk substitutes with various soy bean products on the N metabolism in calves

N-balance trials on young calves aged 3, 5, 7, 9 and 11 weeks, respectively, revealed that a mixture of soybean and whey powder accounting for 39.5% of the total protein amount can be fed without any disadvantage. Feeding this mixture gave N-balance results differing only slightly in the groups aged 7, 9 and 11 weeks. The milk replacer with a higher proportion of soybean and whey powder revealed a more unfavourable N-balance. This allows to conclude that milk replacers containing soybean preparations can be successfully applied to young calves from 5 weeks on, no disadvantages being likely as to N-balance and live weight gain.