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PubMed2004

[Analysis of genetic diversity of preserved population of native chicken breeds by microsatellites and file foundation of markers].

The genetic diversity (allele frequency, mean heterozygosity, mean polymorphic information content(PIC), and Nei genetic distances) of preserved population of 11 native chicken breeds was analyzed by 20 microsatellite markers with high polymorphism. The clustering dendrogram was obtained eventually based on Nei genetic distances of 20 microsatellite. The results showed that 176 alleles were detected of 20 microsatellite loci in 11 native chicken breeds, the average number of alleles of each loci was 8.8 and the range of allele frequencies was 0.013-0.838, and 11 native chicken breeds shared 45 alleles. The average heterozygosity of 20 microsatellite loci was 0.6800-0.7432, the heterozygosity of Zang chicken was the highest (0.7432), and that of Langshang chicken was the lowest (0.6800). The range of PIC of 20 microsatellite loci were 0.6329-0.7023, which is higher than 0.5 and highly polymorphic. By the results of UPGMA tree, four groups were formed from 11 chicken breeds, the first group was Silky, Chahua, Xianju, Zang and Xiaoshan chicken; the second group was Luyuan and Langshan chicken; the third group was Gushi, Fatty and Dagu chicken; and the fourth group was Henan game chicken. The effect of preserved breeds and the differences among generations can be tested by the file foundation of molecular markers, which contained allele frequency, mean heterozygosity, and mean PIC of 20 microsatellite loci in different generation populations.

Alleles↗
PubMedDate not supplied

[Body and claw measurements as well as pressure distribution under the claws in heifers of different cattle breeds].

In 56 heifers of the three breeds German Holstein (GH), German Brown (GB) und German Red (GR) the body weight and height were determined at the age of 350 to 550 days in intervals of 6 to 8 weeks. At the right front limb and the left hind limb the claw measurements dorsal wall length, diagonal length, heel length and height, the angle of the dorsal wall and the hardness of the claw were taken. Furthermore, the punctual pressure under the medial and the lateral claw of the right front limb and the left hind limb were determined using an electronic measuring system. The GH heifers weighing 387.3 kg on an average and having a mean height of 132.3 cm at the sacral bone in the course of the present study were the heaviest and tallest breed at the age of 12 to 18 months. GB had a weight of 366.2 kg and 106.2 cm height at the sacral bone. The GR were the smallest breed (126.0 cm) and weighed 337.7 kg. The heel at the front limb was on the average 1 cm shorter than at the hind limb and it was 0.5 cm lower. The angle of the dorsal border was 4-5 degrees higher at the hind limb. The GR had the flattest claws. The animals showed a larger average weight load on the medial claws than on the lateral claws especially of the front limbs. The highest pressures per cm2 were found underneath the rear part of the medial claw in all breeds. At the front limb, the GB showed significantly higher average pressures per cm2 under the front sectors of the claws than GH and GR, while the other values did not differ significantly between the breeds. The GH tended to have lower average pressures per cm2 underneath the claws of the hind limb, but this was only significant at the front medial sector of the claw.

Animals↗
PubMed2005

[Effect study of white locus (I) on coat color inheritance in Chinese native pig breeds].

The classical White (I) locus is one of the important pig coat color hereditable loci,which is homologous to KIT gene. In this study,PCR-RFLP and PCR-SSCP analysis were commanded on the Intron 17 and 18 nucleotide sequences of KIT gene. The tested results showed that the substitution mutation (G-->A) of Intron 17 was found in white pigs, including Wuzhishan pigs (white), Landrace and Large White,and its genotype (AB) frequency was 1.1 and 0.8 respectively. The genotype frequency was uniformly 0 in the other native pig breeds. Similarly,the deleted mutation (AGTT) of Intron 18 was also found in the same white pigs,its genotype (,AA) frequency was 1.1 and 0.93 separately,while in the other native pig breeds was 0. Accordingly it was considered that KIT gene was an important factor regulating the white coat color genotype, and the classical I locus (KIT gene) was epistatic to the other genetic coat color loci. On the other hand,although the native pig breed Rongchang Pig is similar to Landrace and Large White in phenotype (white coat color), the mutation status found in them was absolutely distinct. So it is presumed that the coat color genetic system of Chinese native pig breeds was different from that of imported breeds.

Animals↗
PubMedDate not supplied

[Population-genetic study of the polymorphism of structural genes and ISSR-PCR markers in some cattle breeds].

The comparative analysis of genetic structures of five cattle breeds has been carried out using polymorphism of two different types of molecular-genetic markers--20 structural genes and 128 DNA loci (the DNA fragments flanked by inverted microsatellite loci repetitions--ISSR-PCR method). In spite of availability of breed-specific singularities of genotype distribution detected by the both methods the level of mean heterozygosity of structural genes was similar in all the investigated breeds. A part of polymorphic loci and the average value of the polymorphic information contents (PIC) of ISSR-PCR markers has appeared much higher in commercial breeds with high effective number in comparison with Ukrainian autochthonous breeds. The population-genetic processes detected by different methods are discussed.

Animals↗
PubMed2006

[Sequence and structure analysis of mitochondrial tRNApro and tRNAthr genes in domestic goose breeds].

We report here the results of the sequence and structure analysis of mitochondrial tRNApro and tRNAthr genes in domestic goose breeds by sequencing the mitochondrial DNA from a total of 25 samples from 6 breeds of Chinese geese and 2 breeds of domestic Europe geese. Sequences and the cloverleaf structure of tRNApro (69 bp) and tRNAthr (68 bp) in domestic goose breeds were described and analysed They were compared amongst the three domestic goose breeds as well as between Anseriformes (Anser cygnoides) and Galliformes (Gallus gallus domesticus, Genbank accession number NC001323). Both goose tRNApro and tRNAthr genes have normal cloverleaf secondary structures. The amino acid arm and the anticodon loop of the cloverleaf structure of tRNApro and tRNAthr are very conservative among Anser albifrons, Anser anser and Anser cygnoides. The gene sequences in this study were deposited to GenBank under accession numbers AY427800-AY427805 and AY427812-AY427814.

Animals↗
PubMedDate not supplied

[Comparative examination of the lateral cerebral ventricles of different dog breeds using quantitative computed tomography].

Due to the great variations among the shape of the skull in different breeds, the routine use of computed tomography in the diagnosis of central nervous diseases in the dog requires basic knowledge of the structure of the inner subarachnoidal spaces. In neoplastic as well as in inflammatory brain disease, changes of the size and shape of liquor filled spaces can be found. In the present study, the easily demonstrable lateral ventricles of the brain of ten dogs of each breed, respectively, without cerebral disease belonging to the breeds German Shepherd (DSH), Dachshund, Boxer, Labrador Retriever and Toy poodle were characterized with regard to their two-dimensional expansion. The average width and height of the lateral ventricles were ascertained for each breed. The Boxer had the relatively largest lateral ventricles, whereas in the other breeds,their sizes were very similar. 32 of the dogs investigated (64%) had symmetric lateral ventricles, and in 18 dogs (36%) they were asymmetric. Of these 18 cases, the left lateral ventricle was larger in 12 dogs (67%).

Animals↗
PubMed1991

[Study of the breed-forming process in sheep using multivariate methods of analysis of genetic and morphologic distances].

Comparison of biochemical genetic variation and morphological variation during formation of a new breed of sheep by means of multi-breed mating has been carried out. Genetic distances calculated by biochemical markers using various methods (by M. Nei, J.S. Rogers, I.I. Cavalli-Sforza and A.W.F. Edvards) have been discovered to significantly correlate with Manhattan and average taxonomic distances calculated on the basis of six morphological traits (r = 0.841-0.889, t = 2.98-2.99, P = 0.999). Nevertheless, it appeared that relationships between crossbred animals revealed with the help of methods for multidimensional analysis (principle component analysis and multidimensional scaling) on the basis of genetic distances matrix more precisely correspond to the real scheme and direction of breeding work than relationships described while using the given methods on the basis of morphological distances matrix. Greater correspondence of data on biochemical genetic variations of the animal groups studied to real processes of breeding, as compared with the data on morphological traits, is supposed to be connected with direct involvement of non-accounted phenotypic characters into the breeding work.

Animals↗
PubMed1991

[The problems of spotted breeds of rabbits. 1. Fattening and body condition at slaughter, organ parameters].

Rabbits of the Giant German Spot Breed and of the English Spot Breed were bred, reared, fattened and evaluated under standardized conditions. A total of 50 animals (31 German spot = DRS; 19 English spot = ES; both derived from mating of heterozygotes) was tested, belonging to the three possible genotypes: Homozygous black (kk), heterozygous spotted (Kk, "standard animals") and homozygous spotted (KK, so-called "Chaplins"). As expected, breed differences consisted of better daily gains and higher carcass weights in DRS, but higher dressing percentages in ES. With respect to colour genotypes, only in DRS-KK depressions of daily gains and carcass weight were observed; food conversion efficiency however was even better in these animals (of both breeds), primarily because of lower feed uptake. Very distinct differences in some important organ traits could be demonstrated for those genotypes: A significantly augmented intestine (abs. and rel.) in KK-animals, specially with reference to the gross intestine--indicating a tendency to motility disturbances and/or chronic obstipation. This predisposition was underlined by the premature loss of three KK-rabbits suffering from severe corresponding symptoms. Seemingly analogous syndromes (Megacolon) in man and other species are cited, though further investigations are needed to clarify the etiology in spot rabbits. Significance of lower heart weights was stated in DRS-KK-animals, probably induced by minor activities observed in this genotype. Thus the K-gene can be classified as a subvital one when homozygous though manifestations of the symptoms obviously vary with the genetic background (breed, line) and perhaps with the environment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Breeding habitats of malaria vectors: A. fluviatilis, A. annularis and A. culicifacies, in Koraput district, Orissa.

Anopheline breeding habitats were studied in two different geoclimatic zones. The vectors A. fluviatilis, A annularis and A. culicifacies breed in all types of habitats. Streams were most productive for the main vector, A. fluviatilis and breeding was intense during winter and early summer. In the rainy season, breeding occurred in terraced paddy fields. A. culicifacies were produced in large numbers in rivers in summer and in paddy fields in rainy and cold seasons. Considering the vastness of these breeding habitats, vector control measures by larviciding or any other bioenvironmental means will not be a feasible alternative even though house spraying poses serious problems in this area due to several reasons. The use of personal protection methods is suggested.

Animals↗
PubMedDate not supplied

[The characteristics of the genetic relations between different breeds and crossbreeds of sheep].

Frequency of occurrence of antigens belonging to 7 systems of blood groups in four breeds of sheep as well as two crosses of the first generation Tsigai X Ostfrisian; Ostfrisian X Tsigai) has been studied. A phylogenetic affinity between them is presented. Indices of genetic distances between breeds and crosses are calculated. The dendrogram demonstrates the existence of two clusters: the first has been formed with the Caucasian, Ostfrisian, Tsigai breeds and both crosses of the first generation: the second--with Astrakhan breed. The analysis of the results obtained shows that dendrogram constructed with regard for the frequency of blood antigens reflects real relations of the investigated sheep breeds according to the adopted systems.

Alleles↗
PubMed1988

[Breeding adaptation to avoid antagonisms between production and health in swine].

Lerner (1954) with his hypothesis of genetic homeostasis has provided the explanation for most of our present antagonism-problems in high performing farm animal populations. Effective artificial selection for highly heritable traits (such as lean content and muscularity in pigs) leads to negatively correlated responses in other traits, particularly the components of reproductive fitness. There are three main antagonisms in our present breeding populations of meat type pigs, which are all caused by the dramatic genetic changes in lean content and muscularity: 1. Poor meat quality and high stress susceptibility. 2. Decreasing reproductive performance. 3. Increased leg weakness problems. The most efficient breeding strategies against these antagonisms are 1. Elimination of the recessive Halothane stress gene from at least one parental population by systematic progeny test procedures. Crossbred progeny from one homozygous stress resistant parent are at least heterozygous stress resistant and have good meat quality. 2. Use of crossbred sows from two parental breeds leads on an average of 10% to a better litter performance than purebred sows. Hybrid sows from selected dam lines can have a markedly better litter performance than 10%. 3. Avoidance of extreme muscularity or carcass length as well as tests and the selection of the breeding stock under practical (strawless) management conditions reduces the incidence. Moreover crossbred boars from unrelated parent breeds show much less leg and libido problems.

Animals↗
PubMed1979

[Some parameters in reproduction of a Maroccain sheep breed (race d'Man) (author's transl)].

The importance of the sheep in Marocco was shown with help of statistical data. As there exist very few scientific work on sheep reproduction in this country, we began to work on local breeds with the race d'Man. The breed is asaisonal and is able to lamb 2 times within 13 months, with mostly 2 or more youngs (1,8 lambs per partum). The delay of gestation was found with 150 days, the duration of a cycle 17 days. The libido shown by the rams is violent. They easily accepted an other male as phantome for the collection of sperm with the easily accepted artificial vagina. The gonads are ovoid formed and are early developed. Remarkable is the tail of the epididymis which is covered in a pocketlike formed structure of the distal scrotum. Its volume is remarkable. Concerning the characteristics of the sperm there is no difference with other breeds. Therefore the conclusion seems reasonable that this apparent development of the epididmymis tail is an organ for thermoregulation for the sperm as the breeds origin are the oasis of the Sahara. The early onset of puberty as well as the violent sexual interest and the high rate of reproduction and asaisonal behavior could be a reference to a "primitive breed".

Animals↗
PubMed1980

Breeding, allocation and maintenance of mice for a large, long-term carcinogenic study (ED01 study).

The breeding, allocation and maintenance data on BALB/c female mice in a 24, 192 mouse chronic carcinogen feeding study are discussed. In establishing the breeding colony, standard derivation techniques were used to develop a barrier-maintained production capability. Genetic histories and other breeding colony records were maintained with the assistance of a computer-supported Breeding Information System. A computer-supported allocation system provided the link between the breeding and experimental portion of the study. Once allocated to the experiment, the mice were weighed and observed weekly; feed consumption data was also collected. All animal and cage information was entered directly into the computer data base via special terminals and electronic balance units. From this experiment's data base, daily and weekly reports were generated which provided valuable information for the operational and scientific management of the experiment.

Animal Husbandry↗
PubMed1994

TaqI restriction fragment length polymorphisms for growth hormone in bovine breeds and their association with quantitative traits.

The objectives of the present study were (1) to reveal GH-TaqI RFLPs in different bovine breeds and (2) to look for association between quantitative traits and GH-TaqI RFLPs in bulls highly selected for growth and meat production. Blood was sampled from 269 Holstein heifers, 48 Italian and 45 Hungarian Simmental heifers, 30 Normande heifers and 41 bulls and 13 heifers of the double-muscled Belgian White Blue breed. Bulls were weighed from 7 until 13 months of age and the average daily gain, the feed efficiency, the height and the phenotypic index were determined at the end of the experiment. GH-TaqI RFLPs revealed 4 DNA fragments of 6 (A), 5.2 (B), 4.4 (C) and 4.2 (D) kbp. The distribution of genotypes was different between Normande and the other breeds (P < 0.001) and between Belgian White Blue and Holstein (P < 0.001) or Hungarian Simmental breed (P < 0.005). The Normande heifers were also characterized by a high frequency of the AB genotype (53%) compared with other experimental breeds (range values: 7-24%). In the statistical analysis of the relationships between quantitative traits and GH-TaqI RFLPs in double-muscled Belgian White Blue bulls, the AC genotypic class was not used because of its low distribution. The AA class showed greater records of weight at 7 (P < 0.07) and 13 (P < 0.06) months of age than the AB class. In conclusion, this study has shown a correlation between the GH-TaqI RFLPs and weight at 7 and 13 months of age in Belgian White Blue bulls.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Use of a DNA-based test for the mutation associated with porcine stress syndrome (malignant hyperthermia) in 10,000 breeding swine.

To test the hypothesis that the mutation associated with porcine stress syndrome (PSS; malignant hyperthermia) was present in a large proportion of North American and English swine, a simple and rapid laboratory protocol was used for cost-effective, large-scale diagnosis of susceptibility to PSS. This PSS test was applied to 10,245 breeding swine of various breeds from 129 farms in the United States, Canada, and England. Approximately 1 of 5 swine was a heterozygous carrier of the PSS mutation, with approximately 1% being homozygotes. Prevalence of the PSS mutation was 97% for 58 Pietrain, 35% for 1,962 Landrace, 15% for 718 Duroc, 19% for 720 Large White, 14% for 496 Hampshire, 19% for 1,727 Yorkshire, and 16% for 3,446 crossbred swine. The PPS gene frequencies for these breeds were 0.72, 0.19, 0.08, 0.10, 0.07, 0.10, and 0.09, respectively. In addition to these breeds, we have identified the PSS mutation in Poland China and Berkshire breeds. These gene frequencies were 30 to 75% lower in Canadian swine than in US swine, with the exception of Yorkshires, for which the gene frequency was threefold higher in Canadian swine. English swine were similarly, or more so, affected than were US swine. Accuracy was estimated at > 99%. Cost to perform the test was < $20/animal. Depending on the perceived net balance of deleterious and beneficial effects of the mutation, the PSS test could be used to eradicate the PSS mutation from herds, or for controlled expression of the mutation.

Animals↗
PubMed1975

[Reproductive capacity and milk production in cows of various cattle breeds as related to age at the ist calving].

The course of parturition, the ability to get in-calf, and milk production were studied in 348 first-calved cows, in 162 cows of the Bohemian Spotted breed, 88 cows of the Black-Pied Lowland breed, and 98 crossbreds of these two breeds divided into three categories according to the age at the first calving (from 21 to 23 months, 24 months, and from 25 to 29 months). There were only slight differences in the average calf birth weight between the cows of all the breeds calving for the first time before the age of 24 months and cows calving later (lower by 0.70 kg, 1.15 kg, 0.80 kg, respectively). The frequency of irregular parturitions and the course of early puerperium did not differ considerably in individual categories under study, either. The average time elapsing from parturition to the first insemination was 58, 63, and 53 days, respectively, in the cows of the youngest category, and 56, 57, and 51 days, respectively, in the oldest category. Similarly, insignificant differences were found in the length of the service period (SP = 94, 95, and 85 days compared to 88, 94, and 80 days) and in the value of the insemination index (2.17, 1.91, and 2.02 compared to 1.92, 2.00, and 1.92). Milk production in early-calving cows in the first lactation was significantly lower than in later-calving cows (3155, 3704 and 3267 kg of milk compared to 3788, 3961, and 3515 kg of milk). If the required live weight at calving is reached, no greater complications of parturition and puerperium occur in the cows calving for the first time at an early age. The indices of further fertility and milk production are also favourable. This justifies the view that the reduction of the pre-production period in heifers and the earliness of the first calving can be considered as a generally recommendable method of the intensification of the reproduction process and as a contribution to the improvement of the profitability of cattle breeding.

Age Factors↗
PubMed1977

Branching of the coeliac artery in some domestic birds. iii. A comparison of the pattern of the coeliac artery in three breeds of the domestic fowl (Gallus gallus f. domestica).

The authors examined the pattern of the coeliac artery and its branches in 100 females of the domestic fowl of three breeds: White Leghorn (33 females), Brown Leghorn (34 females) and White Plymouth (33 females). The arterial pattern was injected by red-dyed latex. An exact analysis of the pattern of branches of the coeliac artery in the individual breeds was made, the individual signs were compared and the level of statistical significance in the differen breed-related findings was determined. On the basis of study of the material it is possible to state that: a) There exist certain differences in the pattern of branches of the coeliac artery in various breeds of the domestic fowl. b) These differences comprise especially the way of origin of the A. proventricularis dorsalis, the origin of spleen arteries, the existence of the accessory arteries for the gall bladder, bile ducts and the duodenum, the origin of the Aa. ileocaecales and the way of branching of the A. gastrica sin. c) It will be possible to compare the pattern of the coeliac artery in various species of birds no sooner than the breed-related differences are determined.

Animals↗
PubMed1996

DNA fingerprinting of captive breeding pairs of lesser white-fronted geese (Anser erythropus) with unknown pedigrees.

For a number of decades, the lesser white-fronted goose (Anser erythropus) has been almost-absent from the Fennoscandian fauna and has a current population size of only about 60 breeding pairs, with fewer than 10 pairs in Sweden. During the period 1981-1991 more than 200 young have been reintroduced in northern Sweden. However, the origin and possible relatedness of lesser white-fronted individuals were unknown when the breeding program started. We have used DNA fingerprinting to assess the similarity of 18 individuals, i.e., the entire captive population used for breeding in 1991 and about 60% of the captive population used in 1981-1991. Minisatellite probe 33.15 provided an index for an average similarity of 0.39 between the mates of the 12 breeding pairs used for producing offspring for reintroduction. This is a higher similarity than in natural populations of birds in general but lower than in populations that have passed through serious population bottlenecks. Individuals originating from different breeders are more dissimilar than those from the same breeder. However, the close relationships (similarity, 0.5-0.6) found in a group of five individuals from different breeders show that selecting individuals from different breeding groups is not sufficient to prevent mating between closely related individuals.

Animals↗