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PubMed2006

How healthy are clones and their progeny: 5 years of field experience.

There is considerable concern regarding the health of cloned cattle and their safety as a source of food. The objective was to summarize 5 years of commercial experience with cloning in three countries (United States, Argentina and Brazil). Overall, only 9% of transferred embryos resulted in calves; efficiency ranged from 0 to 45% (most were from 1 to 10%, but 24% of cell lines never produced live calves). There was no significant difference in pregnancy rate following transfer of one versus two embryos. Before 90 days of gestation, two ultrasound markers for embryo death were found, either crown rump length (CRL) or heart beat less than 7.5mm and 150bpm, respectively, were observed alone or together in 27% of clones that died. In addition, after 100 days of pregnancy, placental edema, hydrops fetalis and increased abdominal circumference size were used as ultrasound findings of a fetus at risk of loss. At 114 days of gestation, abdominal circumference in clones that died was statistically larger than in clones that survived alive to term and from MOET- and IVF-derived pregnancies (P<0.05). Since elective cesarean section (C-section) was partially replaced by natural or assisted parturition, C-section rates decreased from 100% in 2000 to 54% in 2005. On average, 42% of cloned calves died between delivery and 150 days of life; the most common abnormalities were: enlarged umbilical cord (37%), respiratory problems (19%), calves depressed/prolonged recumbency (20%) and contracted flexor tendons (21%). From 11 blood parameters evaluated during the first week of life, lactate decreased twice and glucose doubled its original value from 24h to 7 days. Adult cloned females had normal breeding and calving rates and cloned bulls produced good quality semen and had normal fertility when used for AI or natural mating. In conclusion, cloning had no risks qualitatively different from those encountered in animals involved in modern agricultural practices, although the frequency of the risks appeared to be increased in cattle during the early portions of the life cycle of cattle clones.

Animal Welfare↗

PubMed2003

Patagonian Argentine Creole cattle polymorphism: comparison with North-West populations of this breed.

The relict Patagonian Argentine Creole cattle population consist of a small feral population (Los Glaciares population) that is geographically isolated in the South-West of Patagonia. In order to determine the level of genetic variability of this population, the polymorphism of eight structural genes and two microsatellites loci were studied using the polymerase chain reaction (PCR). In addition, genetic characterisation was used to compare Los Glaciares population and the ACc breed of cattle. Results obtained in this study show that the value of average heterozygosity of the studied loci for the Los Glaciares were not significantly different from the ACc. Furthermore, the data of this report were consistent with the hypothesis that Los Glaciares originated from ACc brought to the area by colonialists in the last century. Such data may be useful in formulating management plans for Feral Patagonian Creole cattle populations.

Alleles↗

PubMed1998

Genetic drift in present human populations: survey of a Mediterranean region (La Alpujarra, South-east Spain).

This paper presents information on the opportunity for genetic drift in La Alpujarra, a rural population of the Spanish Mediterranean. This region is characterized by its historical isolation. The analyses were based on a survey of 45% of the population. The Effective Population Size (NE = 1986), the Effective Migration Rate (M(E) = 12.4) and the Coefficient of Breeding Isolation (CBI = 246.2) of Lasker & Kaplan (1964) were calculated. The value of the latter index indicates that genetic drift in the Alpujarrenian population is negligible at present because of the cessation of reproductive isolation due to the development of communication networks.

Female↗

PubMed2001

Reaction between albumen and 3,3',5,5'-tetramethylbenzidine as a method to evaluate egg freshness.

The 3,3',5,5'-tetramethylbenzidine colorimetric test is proposed as a method for the evaluation of shell egg freshness. A simplification of the original method was tested on albumen, and the modified method was used to study the development of albumen-tetramethylbenzidine reaction in eggs stored at three temperatures for different times. The stability of the reagent solution and the repeatability of the analytical method were also studied. The reaction mechanism showed the predominant role of iron ions on the colorimetric response, and the secondary role of copper ions added to the reaction mix in order to enhance the response. The response coefficient of variation, due to the natural variability in eggs laid by hens of two breeds and different ages, was 10.3%, which is similar to the value obtained for furosine, but lower than those previously observed for other egg freshness indices such as Haugh Unit and air-cell height.

Animals↗

PubMed1998

Pectinate ligament dysplasia and glaucoma in Flat Coated Retrievers. II. Assessment of prevalence and heritability.

Pectinate ligament dysplasia (PLD) in dogs is a congenital ocular abnormality affecting the iridocorneal angle, the presence of which may be associated with adult-onset primary glaucoma. This study demonstrates a significant association between PLD and glaucoma in Flat Coated Retrievers, and also a higher prevalence of PLD in Flat Coated Retrievers compared with other breeds. It is shown that the association between PLD and glaucoma was robust and not due to a small increase in PLD with age. There was also a significant association between PLD in offspring and parents and, using the offspring-parents regression, the heritability of PLD was estimated as approximately 0.7. As glaucoma is significantly related to PLD, glaucoma may also be heritable. Thus, glaucoma can be controlled by gonioscopic examination and elimination of animals with a high degree of PLD from a breeding program. Breeding from only those animals with a moderate or low PLD value or score should limit the expected prevalence of glaucoma in the resulting population to < 0.2%. The preceding study describes in detail the PLD survey, gonioscopic technique and some initial results obtained prior to this epidemiological investigation.

Journal Article↗

PubMed2026

The paradoxical extinction: Exploring signatures of assortative mating as a possible mechanism that maintains canonical Red Wolf genetic ancestry in the American Gulf Coast canids.

Admixed genomes, particularly those with an evolutionary history of genetic exchange with an endangered or extinct species, are valued for innovative and unconventional conservation actions. Here, we show the substantial conservation value that the admixed canids of the Gulf Coast have as they retain high amounts of contemporary Red Wolf ancestry and unique genetic variation of past Red Wolf lineages (e.g. ghost ancestry). We analyzed 54,439 loci genotyped across the genome of 413 North American canids and investigated the role that assortative mating with respect to ancestry proportions played in the retention of endangered genetic variation. We report high correlations of inter-chromosomal ancestry proportions that varied with geographic location along Texas and Louisiana Gulf Coast populations, with the stronger signatures reported in the latter. We found that models of assortative mating promoted greater ancestry variance compared with random mating leading to increased efficiency of selection for Red Wolf and ghost alleles. Despite the Red Wolf being extinct in the wild, original, and ghost genomic variation persists in Gulf Coast admixed canids. We suggest two conservation strategies that value and preserve this unique and endangered genomic variation through designed breeding programs. Ultimately the incorporation of this ghost genetic variation would be valuable to boost the genetic viability of the ex situ Red Wolf breeding program, create in situ redundancy, and avoid extinction for this endemic American wolf species.

Animals↗

PubMedDate not supplied

The genetics of host-pathogen coevolution: implications for genetic resource conservation.

The results of long-term studies of coevolution in the Hordeum vulgare-Rhynchosporium secalis pathosystem are summarized. The genetic systems of barley (host) and R. secalis (pathogen) are complementary: Gene-for-gene interactions among loci affect many traits, leading to self-regulating adjustments over generations between host and pathogen populations. Different pathotypes differ widely in their ability to damage the host, and different host-resistance alleles differ widely in their ability to protect the host from the pathogen. Among 29 resistance loci in the specific host population studied, several played major roles in providing stable resistance, but many had net detrimental effects on the yield and reproductive ability of the host. Resistance alleles that protected against the most damaging pathotypes increased sharply in frequency in the host populations. It is concluded that the evolutionary processes that take place in genetically variable populations propagated under conditions of cultivation can be highly effective in increasing the frequency of desirable alleles and useful multilocus genotypes. This enhances the value of the evolving populations as sources of genetic variability in breeding for disease resistance and other characters that affect adaptedness.

Biological Evolution↗

PubMed1982

Observations on clinical aspects of transmissible gastroenteritis of pigs in Norfolk and Suffolk, 1980-81.

Outbreaks of transmissible gastroenteritis in 56 breeding units, six maiden gilt sites and 64 fattening units were investigated during the period December 1980 to October 1981. The disease invariably occurred in classical virulent form, resulting in very high mortality in baby piglets. Reproductive sequelae were sometimes evident. Individual outbreaks continued for longer than in previous years. There was a high rate of recrudescene, particularly in large breeding units, and infection also persisted in many fattening units. The value of control measures and supportive therapy is discussed.

Abortion, Veterinary↗

PubMed1991

Pituitary and ovarian responses to luteinizing-hormone-releasing hormone during pregnancy and after parturition in brown hares (Lepus europaeus).

Female hares were given an i.v. injection of 5 micrograms luteinizing-hormone-releasing hormone (LHRH) between Days 7 and 19 (n = 21), 20 and 33 (n = 17) and 34 and 41 (n = 17) of pregnancy, and in the 3 days after parturition (n = 16). Whatever the stage of pregnancy, the LHRH injection induced a release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and an acute secretion of progesterone; these hormonal responses increased significantly during pregnancy, to reach values similar to those observed in nonpregnant, nonpseudopregnant females during the breeding season in the 3 days after parturition. However, the release of LH remained monophasic in pregnant and post-partum females, in contrast to the unmated females during the reproductive season, in which there was a biphasic profile. The proportion of ovulating females after LHRH treatment was approximately 60% at the beginning and end of pregnancy; and, after parturition, fell to 23% between Days 20 and 33. After Day 33, the pituitary response to LHRH was significantly higher in ovulating than in nonovulating females. At the beginning of pregnancy, 67% of females aborted after LHRH injection; after Day 20, the incidence of abortion decreased significantly and was 0% from Day 34. The amplitude and duration of progesterone secretion by the new corpora lutea resulting from ovulation after LHRH injection were similar to those of corpora lutea induced in nonpregnant females during the breeding season.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1984

Energy and protein utilization in growing cattle.

Limited data are available to describe the different phases of dietary protein and energy utilization in growing cattle as compared with those in adult cattle or in growing nonruminants. The European data on this topic are summarized to indicate application in appropriate feeding standards. Net protein requirements are widely variable with breed and sex. They are lower in steers than in bulls and lower in early maturing than in late maturing breeds. They are clearly defined for growing and fattening bulls where they are influenced by breed, live weight and live weight gain. New systems have been proposed to express the protein allowances. They provide a great step towards a concept explaining N supply to ruminants. However, protein degradability in the rumen, efficiency of microbial protein synthesis, intestinal digestibility and metabolic efficiency of amino acid absorption in the intestine need to be described more accurately. Even if body energy retention measured by the slaughter technique is systematically lower than when measured by calorimetric balance, both techniques can correctly describe the effect of breed sex, weight, or daily gain on energy retained, in relative value, and its distribution between protein and fat deposition. But further research is needed to confirm the distribution of metabolizable energy between maintenance and growth and the efficiency of metabolizable energy utilization for growth. Thus, different authors have preferred to calculate the energy allowances, not by a factorial method, but by regression between energy intake and the corresponding weight and daily gain of animals measured during feeding trials.

Animals↗

PubMed1993

Vitamin profiles of eggs as indicators of nutritional status in the laying hen: riboflavin study.

Two experiments determined the effect of dietary riboflavin supplementation on egg yolk and albumen riboflavin concentrations, egg production, egg weight, shell thickness, hen weight, hatchability, incidence of clubbed down, and incidence of hemorrhagic embryos. In the first experiment, hens were fed rations containing 1.55, 2.20, 4.40, and 8.80 mg of riboflavin/kg of diet for 27 wk. Significant (P < .05) depressions in both yolk and albumen riboflavin concentrations were noted at the two lower riboflavin levels after 1 wk. Egg production, egg weight, hatchability, and hen weight were all significantly depressed by the two lower riboflavin levels later in the experiment when compared with the two higher levels. Results indicate that egg riboflavin concentrations are related to important production parameters that may be used to predict future dietary riboflavin inadequacies. In the second experiment, hens were fed either an unsupplemented diet or a riboflavin-adequate diet. Measurements of egg albumen riboflavin content, egg production, hatchability, and embryo abnormalities were made twice each week. Results showed depressed albumen riboflavin concentrations and hatchability and increased incidence of hemorrhagic embryos and clubbed down without changes in egg production during the 4- to 7-day period following feeding of the unsupplemented diet. These results show that low albumen riboflavin content immediately affect hatchability and embryonic development. The estimated minimum critical albumen riboflavin concentrations needed to support maximum reproductive function are between 1.9 and 2.9 micrograms of riboflavin/g of egg albumen. These critical values might be used to evaluate riboflavin status of laying and breeding flocks.

Animal Feed↗

PubMed2000

[Genetic diversity of the European bison herd from the Prioksko-Terrasny nature reserve].

Maintaining the existing genetic diversity in populations is one of the most important measures for species conservation. Some components of this diversity in the bison population of the Prioksko-Terrasny Nature Reserve, including the level of preservation of the founder genetic diversity or the founder genomic equivalent (fge) of the current bison stock and the indices of similarity (mk) and genome uniqueness (gu), as well as their effects on viability of the animals from 1950-1995 were studied. The data obtained were treated and the diversity parameters were calculated with the use of the SPARKS software package. This was performed in collaboration with the Institute for Zoo Biology and Wildlife Research (Berlin, Germany). The results of the analysis indicated that, in breeding groups of the European bison, the fge, mk, and gu values should be maintained at levels higher than 1.30, lower than 40%, and higher than 10%, respectively. When selecting males for specific groups of females, the male gu should be at least 20%, and mk should be lower than 40%.

Animals↗

PubMed2001

[The use of memoprint in the cat].

In this study, done in the context of normal veterinary practice, the possibilities of using Memoprint have been evaluated. The values of systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and pulse rate (PR) in healthy cats (n = 72) have been determined, as well as the values of SAP, DAP and PR before (n = 26), during (n = 40) and after (n = 16) an anaesthesia for routine surgery. The results show that Memoprint allows a quick, convenient and correct determination of SAP (average: 122.7 mmHg) and DAP (88.5), but an imprecise determination of the PR. The measures are not highly repeatable with conscious cats (SAP: 0.68, DAP: 0.51), unlike that obtained before (0.90, 0.86), during (0.96, 0.90) and after (0.88, 0.58) the anaesthesia, indicating once again the importance of the cats' familiarity and cooperation with the veterinarian. An analysis of the variance of the values of blood pressure shows their direct relationship with age, sex, breed and style of life of the cats and an increase in pressure in those over ten years of age.

Anesthesia↗

PubMed1997

[Studies on the pharmacokinetics of chloromycetin in Penaeus chinensis].

The pharmacokinetic in the aquatic was valued recently. It is advantageous to avoid blind with medicine in breed Penaeus chinensis. In this paper, studies on the pharmacokinetic parameter of chloromycetin in Penaeus chinensis. Chloromycetin is the stronger medicine in controling Penaeus disease. The 2/1000 contents of antibiotic chloromycetin was added into Penaeus chinensis feed producted with conventional method. The length of Penaeus sample was 9.5 cm. The test makes the Penaeus chinensis be feeded medicine only one time and get samples of Penaeus in different times then cooled immediately. Before analysis dissect, weigh, pre-treat properly and then determine contents in muscle, blood, intestines-stomach and hepato-pancreas. The method for pharmacokinetic study on antibiotic chloromycetin in Penaeus chinensis body was established by HPLC determination. The operating conditions were micro-Bondapak-C18 column, 30:70 (V/V) MeOH/H2O eluent and UV detector. The method is more rapid, accurate and sensitive. The correlation coefficient of the calibration curve is 0.9995 in the range of 1-50 mg/L.

Animals↗

PubMed2005

A PCR multiplex and database for forensic DNA identification of dogs.

Animal-derived trace evidence is a common finding at crime scenes and may provide an important link between victim(s) and suspect(s). A database of 558 dogs of pure and mixed breeds is described and analyzed with two PCR multiplexes of 17 microsatellites. Summary statistics (number of alleles, expected and observed heterozygosity and power of exclusion) are compared between breeds. Marked population substructure in dog breeds indicates significant inbreeding, and the use of a conservative theta value is recommended in likelihood calculations for determining the significance of a DNA match. Evidence is presented that the informativeness of the canine microsatellites, despite inbreeding, is comparable to the human CODIS loci. Two cases utilizing canine DNA typing, State of Washington v. Kenneth Leuluaialii and George Tuilefano and Crown v. Daniel McGowan, illustrate the potential of canine microsatellite markers for forensic investigations.

Animals↗

PubMed1985

Progeny testing with auxiliary traits.

The problem of determining the breeding worth of a male on the basis of the phenotypic values of his female progeny is discussed. The use of one or more auxiliary traits in conjunction with the main trait for progeny testing seems to have an edge over the conventional method in which no auxiliary traits are used. A general expression for the accuracy of selection based on the progeny test is derived and a generalised sire index is proposed. Detailed numerical investigation with one auxiliary trait reveals that the accuracy of the progeny test in such a case is always increased. The maximum gain in accuracy is found when the phenotypic and additive genetic correlations between the main and the auxiliary traits are of opposite signs. The number of progeny required to attain a pre-assigned value of accuracy is determined for several cases. It is found that the use of auxiliary trait reduces this number resulting in decreased cost of the progeny testing programme. The effect of the number of auxiliary traits on the gain in accuracy is also studied under some simplified situations.

Animals↗

PubMed1976

Changes in the blood parameters of an air-breathing fish during different respiratory conditions.

Some of the blood parameters recorded in an air-breathing eel, Amphipnous cuchia under normal respiratory condition during non-breeding period (September-April) are haemoglobin (Hb) concentration 19.26%, haematocrit value 56.16%, RBC number 1.71 million/mm3, RBC size 18.86 X 9.70 mum, mean corpuscular haemoglobin (MCH) 113.4 ng, mean corpuscular haemoglobin concentration (MCHC) 34.2%, blood sugar 77 mg% and ascorbic acid 0.435 mg%. The higher concentration of haemoglobin (19.26%) appears to be related to its obligatory air breathing habit and habitat in a water of low oxygen content. Though a definite trend of increase in the haemoglobin and haematocrit concentration with an increase in the body weight of the fish was lacking, variations were clearly marked related to intrinsic activity of the fish connected with different respiratory conditions. Asphyxiation in a submerged but continuous flow of water (liter/h) for 5 1/2 h resulted in an increase in the above-mentioned parameters to an appreciable extent. These increases were 0.23 million/mm3 in the number of erythrocytes, 6.16% in haemoglobin concentration, 10% in haematocrit value, 20% in blood sugar and 35% in ascorbic acid content. The mean corpuscular haemoglobin showed a decline of 6.2%. Exclusive aerial breathing for 5 1/2 h also caused 7.4% increase in haemoglobin concentration, 9.4% in haematocrit value, 0.14 million/mm3 in RBC number, 20% in blood sugar level, 9% in ascorbic acid content but almost no change in mean corpuscular haemoglobin. The average surface area for diffusion of gases appeared to have reduced by 6.8 mum2 per RBC.

Animals↗

PubMed1997

[Mineral composition of milk from the State of Mérida, Venezuela].

The main mineral components were measured on 132 composite raw milk samples collected in the low and high zones of Mérida State, located in the Venezuelan Andes, by spectrophotometric and atomic absorption methods. The results were grouped to evaluate the effect of the zone (low vs. high) breed (hybred vs. Holstein) and season (dry vs. rain). The mean values and standard deviations (mg/L) were: sodium, 537.0 +/- 143.05; potassium, 1327.9 +/- 133.84; calcium, 952.4 +/- 118.67, phosphorous, 739.2 +/- 97.9; iron, 0.397 +/- 0.1549; magnesium, 82.4 +/- 10.40; copper, 0.589 +/- 0.340; zinc, 7.95 +/- 1.737. These values were higher for the low zones due probably to differences in the production systems. Significant high concentration of iron and copper were obtained which could result in milks susceptible to oxidative rancidity.

Animals↗