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At least 973 records · Page 54Linked to original sources
PubMed1998

Breeding of plums and prunes resistant to plum pox virus.

At Hohenheim we started a plum breeding programme to get new sharka-resistant cultivars with better fruit quality. In the last years we have recognized that the resistance of all cultivated plums is based on quantitative criteria and therefore relative. For this reason we changed our strategy for the resistance breeding. For the first breeding cycle we used special donors with quantitative resistance. Today, the qualitative resistance is more integrated. We intend to combine both types of resistance in the hexaploid genome of Prunus domestica to obtain an absolute and durable resistance. To achieve this aim, we have to consider the evaluation of resistance, the genetic resources, the inheritance of the resistance and also the breeding methods. The results of our resistance breeding study are presented.

Agriculture↗
PubMed1999

[The association of genetic markers in two related swine breeds].

The combinations of genetic markers (allotypes, blood-group systems, and polymorphic proteins) were analyzed in pigs of two phylogenetically related Siberian populations: the newly selected Siberian specialized meat breed SM-1 (daughter breed) and the reproductive core of the Kemerovo breed (maternal breed). Statistically significant interlocus associations were found between the genetic markers that are known not to be linked, being assigned to different linkage groups, and the main selected meat-productivity traits. Some of these associations were shared by both breeds; others were found to be specific to either maternal or daughter populations. Possible genetic mechanisms underlying these associations and their significance are discussed.

Animals↗
PubMed1999

Propofol hydroxylation by dog liver microsomes: assay development and dog breed differences.

Pharmacokinetic studies indicate that clearance of propofol, an anesthetic agent, is slower in greyhounds compared with other dog breeds. Biotransformation of propofol to 2,6-diisopropyl-1,4-quinol (4-hydroxypropofol) by cytochrome P-450 in the liver is proposed as a critical initial step in the elimination of this drug in dogs. Breed differences in the activity of this enzyme could therefore explain pharmacokinetic differences. An in vitro propofol hydroxylase assay was developed and then used to compare enzyme activities in liver microsomes from male greyhound, beagle, and mixed-breed dogs (five each). HPLC of incubate identified only one NADPH-dependent metabolite, which had a chromatographic retention time and UV absorbance, fluorescence, and mass spectra that were identical with authentic 4-hydroxypropofol standard. HPLC with fluorescence detection provided a highly sensitive quantitation method for 4-hydroxypropofol with a quantitation limit of 8 ng/ml using optimized excitation/emission wavelengths (288 nm/330 nm, respectively). Estimates of apparent K(m) and V(max) for propofol hydroxylation by microsomes from a male beagle dog were 7.3 microM and 3.8 nmol/mg/min, respectively. At a substrate concentration of 20 microM, propofol hydroxylase activity was significantly lower (p =.032) in greyhound microsomes (1.7 +/- 0.4 nmol/mg/min) compared with beagle microsomes (5.1 +/- 1.3 nmol/mg/min) but was not statistically different (p =.42) compared with mixed-breed microsomes (3.1 +/- 1.2 nmol/mg/min). These results indicate that there are breed differences in propofol hydroxylase activity and that deficient hydroxylation of propofol by one or more hepatic cytochrome P-450 isoforms may contribute to slow pharmacokinetic clearance of propofol by greyhounds.

Anesthetics, Intravenous↗
PubMed2002

The canine Phosducin gene: characterization of the exon-intron structure and exclusion as a candidate gene for generalized progressive retinal atrophy in 11 dog breeds.

PURPOSE: The exon-intron structure of the canine Phosducin (PDC) gene was identified and the gene evaluated as a candidate for generalized progressive retinal atrophy (gPRA) in 20 dog breeds. METHODS: Intronic sequences of the PDC gene were analyzed after amplification using polymerase chain reaction (PCR) and following sequencing from clones isolated from a canine genomic library. Mutation screening was performed by PCR with single strand conformation polymorphism (SSCP) analysis. Conspicuous banding patterns were analyzed via sequence analyses to detect the underlying nucleotide variations. RESULTS: No polymorphisms were identified after PCR-SSCP analysis within the entire coding region of the PDC gene. A 3 bp deletion in intron intervening sequence (IVS) 3 (position -16 to -18) was observed in 9 breeds, a T->A transversion (position IVS3 -63) in 10 breeds and an A->T transversion (position IVS3 -64) in 2 dog breeds. CONCLUSIONS PDC was excluded as a candidate gene for autosomal recessively (ar) transmitted gPRA in 11 of the 20 dog breeds investigated.

Animals↗
PubMed2004

Cocoa pod (Theobroma caco)--a potential breeding habit of Aedes albopictus in dengue-sensitive Kerala State, India.

Aedes (Stegomyia) albopictus (Skuse), a potential dengue vector, particularly in the foot-hill areas of the Western Ghat region of Kerala State has been found breeding for the first time in cocoa pods (Theobroma cacao) in India. Breeding in cocoa pods is considered an opportunistic adaptive behavior of the mosquito to maintain density in the absence of common breeding sites, especially latex-collecting cups in rubber plantations, during the monsoon periods. Vector breeding in cocoa pods was observed up to 8 m from the ground, and in both hanging and grounded pods, whose endocarp had been devoured by rodents. Ae. albopictus breeding in cocoa plant is discussed in relation to accentuating disease transmission risk.

Aedes↗
PubMed2005

Comparative efficacy of standard AGID, CCIE and competitive ELISA for detecting bluetongue virus antibodies in indigenous breeds of sheep and goats in Rajasthan, India.

The sero-prevalence of antibodies against blue tongue virus (BTV) in 408 local breeds of sheep in Rajasthan state in India was investigated using standard agar gel immunodiffusion (AGID) test. Maximum seropositivities of 11.3% (13/115), 10.7% (13/121), 7.1% (11/155) and 5.9% (1/17) were recorded in the Chokla, Magra, Nali and Pugal breeds, respectively. Out of 107 goat serum samples, 6 (5.6%) were AGID positive. The performance of the standard AGID, counter current immuno-electrophoresis (CCIE) and the competitive enzyme-linked immunosorbent assay (cELISA) for the detection of serum antibody against BTV in indigenous breeds of sheep were compared. Out of 178 sheep serum samples tested, 17 (9.5%), 22 (12.3%) and 54 (30.3%) were positive for group-specific bluetongue antibodies by AGID, CCIE and cELISA, respectively. There was appreciable difference in the seroprevalence detected by AGID, CCIE and cELISA in clinically healthy and diseased sheep with regard to relative sensitivities and specificities of the tests with cELISA being highly sensitive and specific followed by CCIE and AGID test. It was concluded that these indigenous breeds of sheep may be a potential reservoir of BTV infection and cELISA should be routinely used for the detection of antibodies against BTV in these local breeds of sheep.

Animals↗
PubMed2005

[Study on mitochondrial DNA genetic polymorphism of some yak breeds in China].

This study determined yak's complete sequence of mitochondrial DNA control region (D-loop) of 35 individuals in 5 yak breeds at the first time. The result showed that the length of D-loop in yak was 891 -895 bp. Content of nucleotide T, C, A, G were 28.5%, 25.3%, 32.5% and 13.7% respectively. There were 55 polymorphic sites (6.16% in total analyzed sites). The transition,transversion and insertion/deletion were found in this region.24 haplotypes was defined in this study, in which haplotype H4 and H6 were major haplotypes of Chinese yak. The distribution of all the haplotypes among the breeds was disequilibrium. The average diversity of haplotypes were 0.9697 +/-0.0180, indicating the abundance of haplotypes of yak's D-loop. The average nucleotide difference and the nucleotide diversity in Chinese yak breeds were 10.936% and 1.231% respectively. Nucleotide divergence and Kimura 2-parameter distance between yak breeds were 0.760% -2.155%, and 0.000-0.029 respectively. The results indicated that the genetic diversity of Chinese yak was very abundant. Analysis of molecular variance and network construction results indicated that there was significant divergence among Chinese yak breeds. The network construction indicated that Chinese yak had been divided into 2 types and had probably 2 maternal origins or 2 domesticated places.

Animals↗
PubMed1991

Factors associated with spread of pseudorabies virus among breeding swine in quarantined herds.

Knowledge of the factors that place susceptible gilts at highest risk of pseudorabies virus (PRV) infection in a quarantined herd is crucial to reduce spread of PRV within the herd. Cohorts of PRV seronegative gilts were monitored in 17 herds that were endemically infected with PRV to determine the location of breeding females at the time of infection with PRV and identify herd characteristics and management and housing factors that may influence spread of PRV in the breeding section of swine herds endemically infected with PRV. Blood samples were collected every 1 to 2 months for an average of 13.6 months. In addition, blood was collected from a representative sample of finishing pigs (greater than or equal to 20 weeks old) 3 times per year to determine their serologic PRV status. Incidence rates and relative risks of PRV infection were estimated for 4 areas of the breeding section: gestation barn, gilt pool, farrowing room, and breeding area. Overall, 28, 11, 8, and 2 females became infected with PRV in each of these areas, respectively. The greater number of females infected in the gestation barns, compared with the number of females infected in other locations, is probably a consequence of being at risk for a longer period rather than of a higher incidence rate. Herd size, common housing for gilts in the gilt pool and sows, and serologic pattern of PRV infection in finishing pigs were associated with the detection of spread of PRV in the breeding section of the 17 herds.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

[Genetic diversity of indigenous sheep breeds in Shandong Province based on microsatellite markers study].

By using 24 microsatellite markers, this paper studied the genetic diversity of four indigenous sheep breeds in Shandong Province. 467 alleles were detected from 164 sheep of 71 breeding groups, and the proportion of effective alleles was 49.59%. The differences of the allele number among microsatellite loci were larger than those among breeds. 123 peculiar alleles and 43 dominative alleles were found from these sheep. 89% of the microsatellite markers were not in Hardy-Weinberg, and 50% of them were neutral. All the microsattelite markers were of high polymorphic (PIC > 0.5), and the values of Shannon indexes were relatively high. The observed heterozygosities (0.454 to approximately 0.560) were significantly lower than their expected values (0.831 to approximately 0.849). It was suggested that the four indigenous sheep breeds in Shandong Province were highly genetic polymorphic but somewhat inbred. The NJ and UPGRAM dendrograms indicated that the small-tailed and large-tailed Han sheep in west Shandong were closer in genetics, and the Shandi and Wadi sheep in east Shandong were similar. The genetic distances between different sheep breeds were accordant to geographical distances.

Alleles↗
PubMed1987

Breed differences in the frequency of bovine lymphocyte antigens.

Lymphocytes from 1,564 cattle of 18 breeds and cross-bred groups in Australia were tested for major histocompatibility system class 1 antigens. Gene frequencies were calculated for the Angus, Belmont Red, Brahman, Hereford and Holstein-Friesian breeds. There were substantial differences among these breeds in antigen and gene frequency. There were striking differences among all 18 breeds in the presence or absence of certain antigens. Two antigens, CA13 and CA36, were strongly associated in Hereford cattle but occurred independently of each other in the other breeds.

Animals↗
PubMed1988

Effects of age, sex and breed on antipyrine disposition in calves.

In domestic animals relatively little is known about the functions of hepatic microsomal enzymes and their role in biotransformation. In this study, antipyrine was used to assess microsomal oxidative function and particularly to determine the effect of age, sex and breed on drug metabolising enzymes. At birth, the elimination rate of antipyrine was very low as reflected by a half-life of 24 hours. The first two months of life were characterised by a steady decrease of antipyrine half-life values of three to four hours being reached at six months. The decrease observed during early life was not identical in the two breeds used in this experiment. By six months the Friesian calves eliminated antipyrine twice as fast as the Blue White Belgian (BWB) breed: 2.1 +/- 0.3 hours and 4.9 +/- 0.3 hours, respectively. The BWB breed is characterised by muscular hypertrophy and by a relative imbalance in muscle:body ratio. The apparent volume of distribution of antipyrine did not vary with age, sex and breed. No differences in antipyrine clearance were found between male and female calves.

Age Factors↗
PubMed1987

Early growth rates and their relationships to mortalities of five breeds of chickens following exposure to acute gamma radiation stress.

Growth and mortality responses were recorded for 541 chicks, representing five different breeds of chickens, following acute exposures to gamma radiation stress at two days of age. Although there were no statistically significant differences in the LD50/30 of the five breeds studied, Cobb broilers showed the highest (1580R) and White Leghorn bantams the lowest (980R) levels, respectively. Other breeds studied included the standard White Leghorn, Athens Randombreds and a strain of feral bantam. Growth rates of body weights were proportionately more depressed by radiation stress than were body sizes, as measured by the lengths of the culmen, tarsus, middle toe and longest primary wing feather of all 32 day-old survivors. Among these structures, the length of the culmen seemed to be the least affected by radiation stress in all of the breeds studied. Feral bantams were able to tolerate the greatest depression in weight gain before exhibiting mortality at exposures below their LD50/30' while Cobb broilers tolerated the greatest depression of weight gain at higher exposure levels. There was a suggestion that those characteristics which were strongly selected for in the course of a particular breed's development were those which experienced the greatest proportional depressions following exposure to gamma radiation stress.

Animals↗
PubMed1986

Barbiturate anesthesia in greyhound and mixed-breed dogs: comparative cardiopulmonary effects, anesthetic effects, and recovery rates.

The cardiovascular effects, anesthetic effects, and recovery rates were evaluated in racing Greyhounds under barbiturate anesthesia. Greyhounds and mixed-breed dogs of similar body weights were given (by IV route) thiopental (15 mg/kg), thiamylal (15 mg/kg), methohexital (10 mg/kg), and pentobarbital (20 mg/kg). The anesthesia lasted longer in Greyhound than in non-Greyhound mixed-breed dogs given thiopental, thiamylal, and methohexital. The mean times from recumbency to standing were 3 to 4 times longer for Greyhounds anesthetized with thiobarbiturates than for non-Greyhound mixed-breed dogs anesthetized with the same drugs, with recovery times for some Greyhounds lasting more than 8 hours. With thiobarbiturate anesthesia, Greyhounds had long periods of respiratory depression, struggled, and relapsed into sleep, whereas in the other dogs, the recovery was quiet. Respiratory depression related to the stage of anesthesia was produced by all barbiturates, but did not result in significant changes in blood gas values. Rectal temperature decreased in all dogs, but did not result in significant hypothermia. Cardiovascular variables and acid-base estimations in Greyhounds were not significantly different from those in mixed-breed dogs before and during barbiturate anesthesia. Packed cell volumes in Greyhounds were significantly higher than those in non-Greyhound mixed-breed dogs after the thiobarbiturates and methohexital were administered. Total plasma protein concentrations were significantly lower in Greyhounds, compared with those in the other dogs before and during barbiturate anesthesia. Methohexital is a useful alternative to thiobarbiturates for short-duration barbiturate anesthesia in Greyhounds.

Anesthesia, General↗
PubMed1985

Behavioral profiles of dog breeds.

Breed behavior profiles were obtained by a method that was quantitative and free of personal biases. The profiles concerned 13 traits, eg, excitability, snapping at children, watchdog barking, and affection demand, which are of interest to people wanting dogs as pets. Authorities for the development of the profiles were 48 small animal veterinarians and 48 obedience judges, randomly selected from directories so as to represent equally men and women, and eastern, central, and western geographic regions of the United States. Each authority was asked to rank on each of the behavioral traits a list of 7 breeds chosen randomly from a list of 56 breeds. The data were analyzed in a custom-designed computer program that pooled the data and then ranked all 56 breeds on the basis of the 13 traits. The results indicated that some behavioral traits discriminate between breeds better than others. An examination of sample profiles indicated the feasibility of developing a statistically meaningful behavioral profile that integrates comparative rankings of several authorities balanced as to representation of geographic location, sex, and type of experience with dogs.

Analysis of Variance↗
PubMed1985

[Renal excretion of urea in the Merino and Steppe fat-tailed breeds of sheep after a short period of fasting].

Urea excretion was studied in an experiment with two sheep breeds (steppe fat-tailed and merino) on the second day of fasting when the urea concentration in blood increases in fasting animals. The control group in the two breeds was given free-choice feed and water while fasting sheep were given ad libitum only water. Diuresis in both breeds was steady during the experiment. Glomerular filtration rate was not found to vary, in comparison with the control, although the plasma urea concentration rose in fat-tailed sheep (P less than 0.01) as well as in the sheep of merino breed (P less than 0.001). Fractional excretion of urea decreased in fat-tailed sheep (P less than 0.05) and also in the sheep of merino breed (P less than 0.02) while total output of urea remained steady in fat-tailed sheep but it increased in merino sheep (P less than 0.02). Tubular reabsorption of urea on the second day of fasting was observed to be higher by 65% in merino sheep (P less than 0.001), but in steppe fat-tailed sheep the increase was much higher--by up to 180% (P less than 0.001), in comparison with the control. It was demonstrated by the results that the increased tubular reabsorption of urea contributes to the rise of plasma urea concentration in sheep on the second day of fasting.

Animals↗
PubMed1976

Growth and carcass characteristics of cattle and buffalo breeds reared on a dry zone pasture in Sri Lanka (Ceylon).

Growth and carcass characteristics were measured on calves from three cattle breeds-the Sinhala, Red Sindhi and Friesian-and two buffalo breeds-the local buffalo and Murrah. The growth study was carried out on Brachiaria brizantha pasture over a period of 48 weeks. The two buffalo breeds grew fastest followed by the two Bos indicus breeds. The Friesian cattle grew at the slowest rate. The Sinhala and local buffalo had normal haematocrit values while the values for all other breeds were lower. The Sinhala and local buffalo had the highest carcass dressing percentages and the highest muscle; bone ratios. Tenderness measured by Warner-Bratzler shear force values and palatability scores by a taste panel were similar for meat from cattle and buffalo.

Animals↗
PubMed1998

[Population genetic parameters of aboriginal Yakut horses as related to modern breeds of the domestic horse Equus caballus L].

This study was the first to analyze the polymorphic characteristics of a wide range of biochemical markers in aboriginal Yakut horses. A total of 124 alleles, including 48 alleles of seven blood-group loci and 76 alleles of ten loci for enzymes and other proteins, were studied. For these polymorphic systems, a computer analysis of the genetic distances between 85 horse breeds of different origin from all parts of the world was performed. The low level of hereditary variation in the Yakut horses confirmed that this breed is old and has long been an isolated population. Phylogenetic analysis demonstrated that Yakut horses exhibited the most genetic similarity to the breeds from the Central Asian cluster, such as Akhal Teke, Arabian, Yabou, and Caspan Pony (Iran). The dispersal route of ancient horses was revealed. It led from America through Siberia and Central Asia to Africa and Eastern Europe, where evidence of the earliest domestication of horses was found. Genetic and ecological explanations of the formation of racing and draft breeds with similar immunogenetic characteristics are advanced. These explanations agree with craniological data on fossils and with the relative rates of growth of the axial and peripheral skeletons in modern breeds. These data shed light on the initial stages of domestication of the horse, an event that was extremely important for development of the human civilization.

Animals↗
PubMed1998

A comparative study of the haemorheology of various breeds of dog.

Haemorheological parameters in nine breeds of dog were examined. Whole blood viscosity at both high and low shear rates differed significantly between the breeds with a 50% difference between the highest and lowest viscosity at high shear rate and a 140% difference at low shear rate. Athletic breeds (Greyhounds, Deerhounds) had the highest whole blood viscosities. Differences in viscosity correlated well with differences in haematocrit between breeds. When the blood samples were adjusted to a standard haematocrit (45%), there were no significant differences in viscosity. This implied that other rheological factors such as cellular deformability and plasma viscosity did not vary significantly between breeds, and direct measurement showed this to be the case.

Animals↗