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PubMed2006

[Examination of the density of the brain parenchyma in different dog breeds using quantitative computed tomography].

In the present study quantitative computed tomography was used to analyze the absorption density in different localisations of the brain parenchyma comparatively in five different dog breeds. The breeds German Shepherd Dog, Dachshund, Boxer, Labrador Retriever and Miniature Poodle were chosen as representatives of different skull shapes and sizes. The mean absorption density for the German Shepherd Dog was 35.8 HU in the cerebellum, 28.5 - 34.8 HU in several locations of the cerebrum, 39.6 HU in the brain stem and 40.8 HU in the hypophyseal region. In the Dachshund, the mean density was 33.8 HU (cerebellum), 34.3 - 44.2 HU (several locations of the cerebrum), 33.3 HU (brain stem) and 38.6 HU (hypophyseal region). The Boxer showed a mean density of 38.7 HU in the cerebellum, 30.2 - 40.8 HU in several locations of the cerebrum, 35.6 HU in the brain stem and 33.1 HU in the hypophyseal region. The mean absorption density in the Labrador Retriever was 37.2 HU in the cerebellum, 29.4 - 32.9 HU (several locations of the cerebrum), 34.7 HU in the brain stem and 47.5 HU in the hypophyseal region. In the Miniature Poodle the mean density was 33.6 HU (cerebellum), 34.9 - 45.5 HU (several locations of the cerebrum), 32.7 HU (brain stem) and 32.4 HU (hypophyseal region). The study showed that the absorption density of the cerebrum, the brain stem and of the hypophyseal region partly were influenced by the different dog breeds. In the cerebellum no difference of density could be seen in the different breeds. The standardised values for the data of absorption densities of the brain parenchyma are the base for further examinations of dogs with clinical CNS diseases.

Animals↗

PubMed1993

Adjusted 200-day scrotal size as a predictor of 365-day scrotal circumference.

Data collected from 264 bulls of 13 beef breeds at the Michigan Bull Test Station was evaluated to determine if scrotal circumference (SC) adjusted to 200 d of age could be used to predict scrotal circumference at 1 yr of age. Scrotal circumference of each bull was recorded on arrival at the test station and at the time of breeding soundness examination (BSE) and was adjusted to 200 and 365 d of age, respectively. Bulls with adjusted SC>34.0 cm by 365 d of age averaged a larger SC at 200 d (P < 0.0001) and faster scrotal growth (P < 0.0001) than bulls with a 365 d adjusted SC </= 34.0 cm. For all bulls evaluated, mean values differed among breeds for the 200-d SC (P < 0.0001) and the 365-d SC (P < 0.0001) but not for scrotal growth over the test period (P = 0.0773). When only bulls with an SC exceeding 34.0 cm by 365 d were considered, differences among breeds were not significant for the 200-d SC (P = 0.3067), the 365-d SC (P = 0.4083), or scrotal growth (P = 0.9248). The adjusted 200-d SC was positively correlated (partial correlation coefficient = 0.6398) with the adjusted 365-d SC. Least squares linear regression suggests that the 200-d SC accounts for nearly half the variation in scrotal size at 1 yr of age (R(2) = 0.4553). Data from this study suggests that among the bulls evaluated, 200 d old calves with SC >/= 23.0 cm had a 95% probability of achieving SC > 34.0 cm by one year of age. Calves measuring < 23 cm at 200 d had a 54% probability of achieving > 34.0 cm scrotal size by one year. This information can contribute to the selection of breeding bulls that will achieve desirable scrotal size by one year of age.

Journal Article↗

PubMed1998

A deterministic model for the economic evaluation of broiler production systems.

A deterministic model for the economic evaluation of broiler production and the derivation of economic values in broiler breeding was developed and tested. The model distinguishes four production stages: multiplier breeder, hatchery, commercial grower, and processor. The processor is included to determine relationships for the price per kilogram of live weight and the quality of the carcass, either on a "whole sale" or "further processed" base. Quantity of product output for the system is fixed by a predetermined amount of kilogram carcass of final product broilers finished by the commercial grower. Profitability of production and cost prices per unit product for subsequent stages can be calculated. Exogenous parameters are easily changeable in order to calculate profitability and cost prices for different production levels or production circumstances. Economic values can be derived considering influences of changes in genetic merit for performance traits on profitability or cost price, for integrated and nonintegrated production systems. By changing exogenous parameters, the model can also be used to analyze profitability or derive economic values for other meat-type poultry, such as turkey.

Agriculture↗

PubMed1981

Development, validation, and application of a rapid method for detection of ovulation in great apes and in women.

A rapid hemagglutination inhibition test for detection of pregnancy in nonhuman primates has been modified to permit detection of the midcycle luteinizing hormone (LH) peak in hominid species. The test has been validated by correlation with immunoassayable LH activity in serum and urine. It has been used by the authors and others from prediction of ovulation in the gorilla, orangutan, chimpanzee, and human. This predictive capacity has been of value to experiments in natural breeding, artificial breeding, and ovum recovery. The test has potential value for monitoring of the normal menstrual cycle, enhancement of breeding efficiency, and identification of anovulatory cycles.

Animals↗

PubMed1983

[Role of genetic factors in the occurrence of umbilical hernias in cattle. II. Heredity and the incidence of umbilical hernia in various crossing variants].

To determine ethyology of Hernia umbilicalis in black-spotted cattle stock, a check crossing was carried out. The incidence of anomalia in the bull progeny of Zakaznik 82 (black-spotted breed) was 44%, this value being 107 in the progeny of Block 107 (holsteinfrisish breed) and 0% in the progeny of Vyaz 338 (holmogorsky breed). The data obtained indicate that Hernia umbilicalis is a hereditary anomaly in cattle.

Animals↗

PubMed1996

Association of somatotropin (BST) gene polymorphism at the 5th exon with selection for milk yield in Holstein cows.

A selection project produced control cows from continuous matings with breed average bulls for predicted transmitting ability for milk (PTA-milk) in 1964 and select cows from matings to four of the highest PTA-milk bulls each year since 1964. Blood samples were collected in 1992 when milk yield difference of select and control line cows exceeded 3,800 kg of milk/305-day lactation. Genomic DNA from control (n = 49) and select (n = 101) cows was analyzed for the presence of variants associated with amino acid position 127 (leucine, AluI[+]; valine, AluI[-]) of bovine somatotropin (bST). Amplification of a 428 base-pair fragment of the bST gene from individual cows, subsequent restriction enzyme (AluI) digestion, and separation resulting fragments indicated three genotypes AluI(+/+), AluI(+/-), and AluI(-/-) in 110, 39, and 1 animal(s), respectively. Gene frequencies of leucine127 and valine 127 alleles were similar for control (0.867m 0.133) and select (0.861, 0.139) animals. United States Department of Agriculture-PTA values were compared between the two genotypes, AluI(+/+) and AluI(+/-). Estimated breeding value for milk (EBV-milk) and average yield deviation for milk (AYD-milk) were not associated with genotype for control animals. However, presence of the valine allele was correlated with decreased EBV-milk (P = 0.03) and AYD-milk (P = 0.16) in select animals and accounted for a decrease of approximately 170 kg of EBV-milk and 240 kg of AYD-milk.

Animals↗

PubMed2005

Serotonin transporter kinetics in rats selected for extreme values of platelet serotonin level.

By selective breeding of Wistar rats for the extreme values of platelet serotonin (5HT) level (PSL), we have developed earlier two sublines of animals differing markedly in this parameter. Further studies, performed on the protein and mRNA levels, revealed platelet serotonin transporter (5HTt) as parameter underlying mentioned differences in PSL between sublines. In this work, we have performed full-kinetic analysis of platelet serotonin uptake (PSU) in animals from the genetically selected sublines. The results demonstrated marked differences in maximal velocity (V(max)) of the 5HT transporter, as contrasted to the lack of any difference in the Michaelis constant (K(m)). High correlation between PSL and V(max) of PSU was demonstrated, revealing that the number of membrane 5HT transporter sites is under genetic control and responsible for marked differences in PSL between high- and low-5HT sublines. These results enabled further selective breeding of animals for the extremes of V(max) of platelet 5HT transporter, and so the development of more specific model "Wistar-Zagreb 5HT rats".

Animals↗

PubMed2000

Relationships between the endangered Pustertaler-Sprinzen and three related European cattle breeds as analysed with 20 microsatellite loci.

We estimated the genetic relationships between the endangered German Pustertaler-Sprinzen cattle breed and the Pinzgauer, Vosges and Simmental breeds--decided upon after consultation of the available historical literature. Within-breed diversity of the four breeds was also assessed. Twenty microsatellite markers were amplified in 27-50 unrelated individuals from populations of each breed. Within-breed variation was estimated from average heterozygosity values and mean number of alleles. Breed relationships were evaluated by genetic distance and a neighbour-joining tree was calculated from these estimates. Bootstrap resampling of loci tested the robustness of the tree topology obtained. A tree was also constructed from distance matrices using individual animals as operational taxonomic units. From both the average heterozygosity values and mean number of alleles calculated, the Pustertaler breed appears to be no more genetically impoverished than the other breeds analysed. The breed tree showed an 85% support for the Pustertaler-Pinzgauer grouping, and this result is echoed in the genetic distance values and allele-sharing individual tree.

Animals↗

PubMed2004

Relationships between sexual behaviour, dominant follicle area, uterus ultrasonic image and pregnancy rate in mares of two breeds differing in reproductive efficiency.

Weak or equivocal expression of oestrous behaviour, related to different level of mares' reactivity, may cause problems in oestrus detection and thus influence the reproductive efficiency. The aim of the study was to test whether a breed characterised by low pregnancy rate and high emotional reactivity (Thoroughbreds) differs in oestrous behaviour from a primitive breed with higher reproductive efficiency (Koniks). Additionally, the follicle size was examined to determine how it influences the intensity of oestrus and uterine ultrasonic image and whether the pregnancy rate differs in relation to the intensity of oestrous behaviour and the size of the dominant follicle(s) area on day preceding ovulation in both breeds. During four reproductive seasons the behaviour of 20 Konik polski (K) and 37 Thoroughbred (T) was observed during daily teasing. Simultaneously, the ultrasonic examinations of the reproductive system were carried out. The behaviour of mares was quantified by scoring on an 8-point scale (behavioural score, BS), according to increasing sexual receptivity. Cross-sectional follicular area (FA) was taken as a product of the two largest perpendicular follicular diameters and mean values for each breed were estimated on 1693 and 1982 mm2 for K and T mares, respectively (P < 0.05). Mares were classified according to the pooled area of dominant follicle (FA) during the preovulatory period: group A (FA < or = breed mean) and group B (FA > breed mean). Uterus image (UI) was scored (1-5) according to the increasing uterine echogenicity. The BS was higher (P < 0.01) in K mares (BS = 5.19) than in T mares (BS = 4.04). The BS was significantly related to increasing follicular area (FA). There was no breed difference in uterus image (UI) score. However, significant regression of UI on FA was found in K mares. The intensity of oestrus was positively related with UI (r = 0.29; P < 0.01) only in K mares, no such relationship was found in T mares. The pregnancy rate was significantly higher for K mares (88.5%) than for T mares (46.0%) and lower for T mares with less intense oestrous behaviour (29.4%) as compared to T mares with more intense oestrus (60.0%). No differences in pregnancy rate was found in mares belonging to A or B group of follicular area. The ascertained weaker oestrous behaviour in Thoroughbred was related to lower pregnancy rate. It is hypothesised that oestrus intensity may be the result of breed differences in the response of the neural system to follicular secretions, or may be an effect of higher incidence of multiple non-synchronic ovulation and/or higher sensitivity to stress in Thoroughbred mares.

Animals↗

PubMed2003

Body condition, migration, and timing of reproduction in snow geese: a test of the condition-dependent model of optimal clutch size.

The seasonal decline of avian clutch size may result from the conflict between the advantage of early breeding (greater offspring value) and the advantage of a delay in lay date (improved body condition and hence clutch size). We tested predictions of a condition-dependent individual optimization model based on this trade-off (Rowe et al. 1994) in a long-distance migrant, the greater snow goose (Chen caerulescens atlantica), using data on condition, migration, and reproductive decisions of individuals. We closely tracked radio-marked females at their main spring staging area and on their breeding grounds. Our results were consistent with predictions of the model. Early-arriving females had a longer prelaying period and initiated their nests earlier than late arrivals. After controlling statistically for arrival date, we determined that females with high premigration condition had an earlier lay date than those in low condition. After controlling for the seasonal decline (i.e., lay date), we observed that clutch size was not related to premigration condition. Moreover, we took advantage of an unplanned manipulation of the prebreeding condition that occurred during our long-term study. We found that a reduction in condition caused a delay in lay date. However, after controlling for the seasonal decline, it did not affect clutch size. Our study indicates that geese simultaneously adjust their lay date and clutch size according to their premigration condition and migratory behavior as predicted by the condition-dependent optimization model.

Animals↗

PubMed2004

Urinary glucocorticoid excretion in the diagnosis of hyperadrenocorticism in ferrets.

Hyperadrenocorticism in ferrets is usually associated with unaltered plasma concentrations of cortisol and adrenocorticotropic hormone (ACTH), although the urinary corticoid/creatinine ratio (UCCR) is commonly elevated. In this study the urinary glucocorticoid excretion was investigated in healthy ferrets and in ferrets with hyperadrenocorticism under different circumstances. In healthy ferrets and in one ferret with hyperadrenocorticism, approximately 10% of plasma cortisol and its metabolites was excreted in the urine. High-performance liquid chromatography (HPLC) revealed one third of the urinary corticoids to be unconjugated cortisol; the other peaks mainly represented cortisol conjugates and metabolites. In 21 healthy sexually intact ferrets, the UCCR started to increase by the end of March and declined to initial values halfway the breeding season (June). In healthy neutered ferrets there was no significant seasonal influence on the UCCR. In two neutered ferrets with hyperadrenocorticism the UCCR was increased, primarily during the breeding season. In 27 of 31 privately owned ferrets with hyperadrenocorticism, the UCCR was higher than the upper limit of the reference range (2.1 x 10(-6)). In 12 of 14 healthy neutered ferrets dexamethasone administration decreased the UCCR by more than 50%, whereas in only 1 of the 28 hyperadrenocorticoid ferrets did the UCCR decrease by more than 50%. We conclude that the UCCR in ferrets primarily reflects cortisol excretion. In healthy sexually intact ferrets and in ferrets with hyperadrenocorticism the UCCR increases during the breeding season. The increased UCCR in hyperadrenocorticoid ferrets is resistant to suppression by dexamethasone, indicating ACTH-independent cortisol production.

Adrenocortical Hyperfunction↗

PubMed1999

Osteochondrosis in cattle.

Osteochondrosis is a poorly understood condition that affects many species, including cattle. Its incidence is not fully appreciated in the cattle industry for many reasons. Most of the reports show a male, purebred predilection, but this may simply be a result of the typical population for which medical attention is sought. With the increasing value of female breeding stock, a less skewed distribution of the disease will most likely result. Distribution of lesions is similar to that in the horse, with the stifle and tarsus most commonly affected. Treatment is divided into medical and surgical options, but neither seem to be strikingly effective as of yet. Surgical techniques include arthroscopy and arthrotomy, and both have their complicating factors. How osteochondrosis as a disease will affect the cattle industry is still to be decided. If the incidence rate does increase with more animals being valued for their economic potential, then treatment options will surely be reevaluated and refined.

Animals↗

PubMed1993

Effects of formaldehyde fumigation of housing on carotenoid pigmentation in three breeds of chickens.

Three breeds of chickens (two broiler breeds, A and B, and one layer breed, C) were raised from 1 day to 3 wk of age in either standard housing or housing additionally fumigated with formaldehyde. Groups of chicks from each breed in both housings received either regular poultry starter ration or this ration supplemented with marigold meal. At 3 wk of age, chicks of all three breeds had higher (111, 113, and 115%) mean body weights when raised in fumigated housing. There was no significant effect of supplemental carotenoids on body weight. Chicks of all three breeds raised in fumigated housing had significantly higher plasma carotenoid concentrations when fed either regular or supplemented feed, and, with the exception of Breed A on regular feed, also had significantly increased skin carotenoid values. No significant differences among breeds in plasma or skin carotenoid values were seen in chicks fed regular ration. However, significant differences were seen among groups of chicks fed supplemental carotenoids. The layer breed, C, had the highest percentage increase in carotenoid pigmentation when fed the carotenoid-supplemented diet in fumigated housing.

Animal Feed↗

PubMed2006

Financial analysis of various strategies for the control of Neospora caninum in dairy cattle in Switzerland.

The present study was conducted to estimate the direct losses due to Neospora caninum in Swiss dairy cattle and to assess the costs and benefits of different potential control strategies. A Monte Carlo simulation spreadsheet module was developed to estimate the direct costs caused by N. caninum, with and without control strategies, and to estimate the costs of these control strategies in a financial analysis. The control strategies considered were "testing and culling of seropositive female cattle", "discontinued breeding with offspring from seropositive cows", "chemotherapeutical treatment of female offspring" and "vaccination of all female cattle". Each parameter in the module that was considered to be uncertain, was described using probability distributions. The simulations were run with 20,000 iterations over a time period of 25 years. The median annual losses due to N. caninum in the Swiss dairy cow population were estimated to be euro 9.7 million euros. All control strategies that required yearly serological testing of all cattle in the population produced high costs and thus were not financially profitable. Among the other control strategies, two showed benefit-cost ratios (BCR) >1 and positive net present values (NPV): "Discontinued breeding with offspring from seropositive cows" (BCR=1.29, NPV=25 million euros ) and "chemotherapeutical treatment of all female offspring" (BCR=2.95, NPV=59 million euros). In economic terms, the best control strategy currently available would therefore be "discontinued breeding with offspring from seropositive cows".

Animals↗

PubMed2001

Large body size in the dog is associated with transient GH excess at a young age.

The main determinants of body size are GH and IGFs. The aim of this study was to investigate whether differences in adult body size of medium-sized and giant dog breeds can be explained by differences in GH release and/or in plasma IGF-I and IGF-II concentrations at a young age. The basal plasma concentrations of GH, IGF-I and IGF-II were determined once weekly in six Great Danes and six beagles from the age of 6 weeks until the age of 24 weeks. In addition, the 6 h secretory profile of GH was determined every 2 weeks. Basal plasma GH concentrations as well as the total area under the curve (AUC) and the AUC above the baseline for GH were significantly higher in Great Danes than in beagles of the same age. In contrast, plasma IGF-I and IGF-II concentrations did not differ significantly between the two breeds. Compared with values in adults, the basal plasma GH concentrations were high until the age of 7 weeks in the beagles, whereas in the Great Danes the basal plasma GH levels remained high during the entire observation period, albeit with a gradual decline. The mean frequency and the mean amplitude of GH pulses tended to be higher in Great Danes than in beagles, although a significant difference was only reached at the age of 19 and 23 weeks for the frequency and at the ages of 9, 11 and 13 weeks for the amplitude. An age-dependent decrease in pulse frequency occurred in the Great Danes. The results of this study demonstrate that differences in adult body size of medium-sized and giant dog breeds are preceded by differences in GH release and not by differences in circulating IGF-I or IGF-II concentrations. Both young Great Danes and young beagles experience a period of high GH release, but this period persists much longer in Great Danes. It is discussed that this difference may be due to delayed maturation of the inhibitory influences of somatostatin on pituitary GH release in the latter dogs.

Animals↗

PubMed2004

Genetic characterization of the Indian cattle breeds, Ongole and Deoni (Bos indicus), using microsatellite markers - a preliminary study.

BACKGROUND: Molecular characterization of cattle breeds is important for the prevention of germplasm erosion by cross breeding. The Indian zebu cattle have their significant role in evolution of present day cattle breeds and development of some of the exotic breeds. Microsatellites are the best available molecular tools for characterization of cattle breeds. The present study was carried out to characterize two Indian cattle breeds, Ongole and Deoni, using microsatellite markers. RESULTS: Using 5 di- and 5 tri-nucleotide repeat loci, 17 Ongole and 13 Deoni unrelated individuals were studied. Of the ten loci, eight revealed polymorphism in both the breeds. The di-nucleotide repeat loci were found to be more polymorphic (100%) than tri-nucleotide repeat loci (60%). A total of 39 polymorphic alleles were obtained at 4.5 alleles per locus in Ongole and 4.1 in Deoni. The average expected heterozygosity was 0.46 (+/-0.1) and 0.50 (+/-0.1) in Ongole and Deoni breeds, respectively. The PIC values of the polymorphic loci ranged from 0.15 to 0.79 in Ongole and 0.13 to 0.80 in Deoni breeds. Six Ongole specific and three Deoni specific alleles were identified. The two breeds showed a moderate genetic relationship between themselves with a FST value of 0.117 (P = 0.01). CONCLUSIONS: This preliminary study shows that microsatellite markers are useful in distinguishing the two zebu breeds namely, Ongole and Deoni. Further studies of other zebu breeds using many microsatellite loci with larger sample sizes can reveal the genetic relationships of Indian breeds.

Animals↗

PubMed1978

Pregnancy rates and non-return rates following artificial and natural breeding in dairy herds.

Information routinely supplied during the conduct of a dairy herd health program was analysed to evaluate the performance of artificial breeding in Victoria. A comparison was made between 60 to 90-day non-return rates (supplied by artificial breeding centres) and pregnancy rates (determined by manual pregnancy diagnosis) for first artificial inseminations in 108 herd years in which both items were available in the 1973 and 1974 breeding seasons. The values were 69.3% and 58.2% respectively (P less than 0.001). Non-return rates and conception rates were found to decline as herd size increased. Pregnancy rates to first artificial and natural services did not differ significantly from each other but pregnancy rates were significantly more variable to natural than artificial service (P less than 0.001). The mean pregnancy rate to artificial insemination for all herd years studied was 57.5% and the pregnancy rate to natural service was 58.0%.

Animals↗

PubMed1996

M-mode echocardiographic diagnosis of dilated cardiomyopathy in giant breed dogs.

M-mode echocardiograms were recorded from 62 giant breed dogs without historical, clinical, electrocardiographic and roentgenologic signs of heart disease, from six dogs with asymptomatic dilated cardiomyopathy (DCM, NYHA class I), and 13 dogs with symptomatic DCM (NYHA class III-IV). There was a general trend that several echocardiographic parameters were significantly in control Great Danes as compared to Newfoundlands and Irish Wolfhounds. There were substantial differences in left ventricular size both in systole and diastole and in systolic indices of the left ventricle between the control group, the asymptomatic dogs and symptomatic dogs with DCM (P = 0.0001). There was also a significant decreased in the interventricular septum thickness (P = 0.0001) and left ventricular free wall thickness in systole (P = 0.002) and diastole (P = 0.005) between the three groups. Furthermore, the left atrial/aortic ratio was significantly different between the three groups (P = 0.0001). It was concluded that this study established echocardiographic reference values in giant breed dogs which may be useful in the study of heart diseases in giant breed dogs.

Animals↗