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PubMed1986

Effect of nutrition, age and size on compensatory growth in two breeds of steers.

Compensatory gain in cattle was studied to determine if age, previous rate of gain or size were factors of importance. A factorial experiment was conducted with growing diet regimen (control vs restricted), age [spring-born (older) vs fall-born (younger)] and breed (Angus vs Charolais) as the factors. During a growing phase, the two diets, (control = dehydrated alfalfa pellets; restricted = cubed grass-alfalfa hay, cottonseed hulls and soybean meal) were fed to both the older and younger steers of each breed to provide groups of similar age but different weights (growing regimen within age) and groups of similar weights but different ages (older-restricted vs younger-controls) at the time at which the steers were switched to a high concentrate diet. Interactions of breed with age and previous growing regimen diet on digestibility of some nutrients in the finishing diet were evident. During the growing phase, control steers averaged .72 kg/d gain, whereas the restricted steers averaged .25 kg/d. The older-restricted steers compensated (P less than .05) from 30 to 120 d after the beginning of the feedlot phase compared with older-control steers. Rates of gain of younger steers were intermediate to those of the older steers throughout the finish phase and were not influenced by growing diet, except on d 30. Rate of gain during the growing phase was negatively correlated (P less than .05) with rate of gain during the finishing phase (60 to 120 d). Within breed, weight at the beginning of the feedlot phase also was negatively correlated with gain during the finishing phase. Skeletal growth was reduced (P less than.05) by the restricted diet during the growing phase, and small compensation (P greater than .05) was observed during the finishing phase. Feed/gain for restricted steers was slightly lower (P greater than .05) than control steers. Younger steers were more efficient (P less than .05) overall in converting dry matter to gain, due to the relatively shorter growing phase when compared with the older steers. These data indicate that both previous gain and weight upon realimentation are influential on compensatory growth.

Aging↗

PubMed1987

Reproductive rates, birth weight, calving ease and 24-h calf survival in a four-breed diallel among Simmental, Limousin, Polled Hereford and Brahman beef cattle.

Calving and weaning rates, birth weight, calving ease, and 24-h calf survival were evaluated in a four-breed diallel of Simmental (S), Limousin (L), Polled Hereford (H) and Brahman (B) beef cattle in five calf crops. Limousin dams tended to have the highest calving and weaning rates because they were able to have heavier calves with less calving difficulty and higher survival rates. Brahman-sired calves were the heaviest at birth (P less than .05) and B dams produced the lightest calves (P less than .001). Lower birth weights tended to be the limiting factor on survival of these calves. A linear comparison among means to evaluate purebred, additive, maternal and specific combining ability effects showed most of the reduction in birth weight from B dams was due to maternal effects. Breed of dam accounted for a higher proportion of variation in calving ease than did sire breed. Simmental sires had significantly heavier calves at birth and S and H dams tended to have more calving difficulty and lower survival rates. Heterosis for these traits was generally not significant. Correlations were generally positive and significant for birth weight and calving ease, but were more variable for birth weight and survival. Linear regressions of calving ease on birth weight both within years and within dam-breed-year subclasses were very similar in that the association of these two traits was reduced as dam age increased.

Animals↗

PubMed1987

Breed differences in uterine and ovarian measurements in gestating swine.

Ovulation rate, ovary weight, corpora lutea weight and uterine length were measured at 10 or 35 d of gestation in Duroc (199) and Yorkshire gilts (114). Embryos were counted at d 35. Yorkshires had significantly more corpora lutea than Durocs (13.6 vs 12.3 at d 10; 13.9 vs 12.4 at d 35). At d 10 breeds did not differ in uterine length, but by d 35 Duroc uteri were longer (P less than .01) than Yorkshire uteri (411 vs 375 cm) despite having fewer (P greater than .05) embryos (9.9 vs 10.5). Ovary weight did not differ between breeds at 10 or 35 d. Homogeneity analyses showed that the correlation matrices were significantly different between breeds at d 35 but not at d 10. In Durocs, high positive correlations existed between total embryo number and corpora lutea number (.57), ovary weight (.53) and corpora lutea weight (.25), whereas corresponding correlations were small in Yorkshires (.21, -.02 and -.03, respectively). In Yorkshires, strong negative correlations existed between total embryo survival and corpora lutea number (-.55), ovary weight (-.30) and corpora lutea weight (-.55), but in Durocs corresponding correlations were small (-.12, .14 and -.10, respectively). These results suggest that animal scientists should consider breed differences in levels of performance and its relationships among traits when designing or interpreting experiments.

Animals↗

PubMed2005

Estimation of extinction probabilities of five german cattle breeds by population viability analysis.

The estimation of the expected loss of genetic diversity and marginal diversities in a set of breeds within a defined future time horizon requires initial estimates of breed extinction probabilities. In this study, the extinction probabilities of 5 German dual-purpose cattle breeds were estimated by population viability analysis. Regression was used to estimate the infinitesimal mean and variance of the population growth and this was based on the diffusion approximation of the density independent population growth (also known as the Dennis regression model). The annual number of milk-recorded cows in each breed was used as census data. Based on the regression results, the extinction probabilities and their confidence intervals were estimated for a wide variety of future time horizons using Monte Carlo time series simulations. The estimates of extinction probabilities were sensible, but in 2 cases they depended heavily on the time horizon considered. Additionally, the confidence intervals became very wide with an increased time horizon. We recommend the estimation of extinction probabilities for a set of future time horizons rather than for a single future time and the selection of an upper bound for this set that is not too large to be meaningful. The validity of the use of the number of milk-recorded cows as census data and of the model assumptions is discussed in detail.

Animals↗

PubMed1981

Colostral immunoglobulin concentrations among breeds of dairy cattle.

Colostral immunoglobulin concentrations were compared among five breeds of dairy cows. Colostrum samples (3 to 4 kg) were obtained immediately after parturition from 19 Ayrshire, 17 Brown Swiss, 12 Guernsey, 19 Holstein, and 5 Jersey cows. Average total colostral immunoglobulin was 8.1, 6.6, 6.3, 5.6, and 9.0% for them. Colostrum from Jerseys had the highest immunoglobulin G (6.65%), immunoglobulin A (1.86%), and immunoglobulin M (.53%) of all breeds. Colostrum from Holsteins was lowest in immunoglobulin G (4.12%) whereas that from Guernseys was lowest in immunoglobulin A (.90%) and immunoglobulin M (.39%). Breeds may differ, and the high calf mortality and health problems frequently reported for Guernseys may be related to the low immunoglobulins A and M in colostrum. Concentration of colostral immunoglobulin by calving number was examined over breeds for 23, 16, 17, and 14 cows by first, second, third, and fourth or later calvings. Colostral immunoglobulin was lower from first-calf heifers (5.68%) than from third (7.91%) and fourth (7.53%) parity cows. Colostral immunoglobulins A and G tended to be lower in first lactations.

Animals↗

PubMed1985

Differences in modified contemporary comparison sire evaluations from first and later lactations by breed.

Sire evaluations from three sets of daughter records, first records only (first), later records after firsts (later), and all records (all) by Modified Contemporary Comparison procedures were used to examine differences in first and later lactation evaluations by breed. January 1984 evaluations for milk for 767 Ayrshires, 3,175 Guernsey, 29,498 Holstein, 3,530 Jersey, and 984 Brown Swiss bulls with 10 or more daughters in each set were used. Average differences between evaluations (later minus first) were 36, 0, 6, 35, and 35 kg milk for Ayrshire, Guernsey, Holstein, Jersey, and Brown Swiss bulls. Standard deviations of the difference were 114, 94, 142, 91, and 134 kg, showing considerable sire-to-sire variation in difference. Correlations between evaluations based on first and later records were .84 to .86 for all breeds except .92 for Jerseys. Percent of first lactations culled was correlated .20, .18, .16, .16, and .19 with difference for Ayrshire, Guernsey, Holstein, Jersey, and Brown Swiss, indicating that culling produced larger differences between evaluations for first and later lactations in favor of later evaluations. Prediction of sire evaluation from later records was enhanced by knowledge of sire's age in addition to first evaluation for Guernsey, Holstein and Jersey sires. In these breeds, for a constant first evaluation, and percent culled in first lactation, younger bulls had higher evaluations from later records. This study showed important differences between evaluations from first and later records for all breeds.

Animals↗

PubMed1982

Crop volume of chickens as affected by body size, sex, and breed.

Single Comb White leghorn (SCWL) hens, broiler cockerels, and two weight classes of SCWL roosters were utilized to determine the relationships of breed, sex, and body size to crop volume. Crop volume was significantly different (P less than .05) among all types of birds examined. Significant differences (P less than .05) of crop volume per kilogram body weight occurred between birds of opposite sex within a breed and between birds of identical sex but differing breed. However, within a breed, birds of identical sex but differing body size exhibited similar crop volume (cc/kg body weight).

Animals↗

PubMed1986

Hepatic mitochondrial activity in two breeds of chicken.

Respiration rates and efficiencies of oxidative phosphorylation of hepatic mitochondria from mature Hubbard White Mountain Cross broiler and White Leghorn layer hens were compared. Broiler hen mitochondria consistently tended to exhibit higher succinate-supported State 3 respiration rate, respiratory control ratio, and ratio of adenosine diphosphate to oxygen, although breed differences were not statistically significant. Within-breed variation in mitochondrial activity was not associated with body weight or egg production. Hepatic tissue of broiler hens yielded significantly more protein in the mitochondrial fraction than tissue of layer hens. In vitro mitochondrial mixtures representing equal wet tissue weights from each breed showed mitochondrial activity intermediate between the two breeds.

Animals↗

PubMed2005

Prevalence of porcine endogenous retrovirus in Chinese pig breeds and in patients treated with a porcine liver cell-based bioreactor.

AIM: To determine the prevalence of porcine endogenous retrovirus (PERV) in various pig breeds raised in China including Chinese experimental mini-pigs by PERV-reverse transcriptase (PERV-RT enzyme). Moreover, the potential for infection of PERV was investigated in patients treated with a bioreactor based on porcine liver cells (n = 3). METHODS: Pig serum, liver and muscle cell-free supernatants were collected from various Chinese pig breeds. Porcine hepatocytes were isolated with a two-step perfusion method. Three patients with acute or chronic liver failure were treated with a bioartificial liver support system (BALSS) for 8-12 h and serum samples were collected from the patients before, immediately after and 30 d after treatment. RESULTS: The activities of PERV-RT enzyme in pig liver and muscle cell-free supernatants were higher than in normal human controls. PERV-TR enzyme activity did not increase in patients before and after 1 mo of treatment. PERV-RT activities were not significantly different when compared with pre-treatment group (1.544+/-0.155576), the post-treatment groups (1.501+/-0.053507, 1.461+/-0.033808 and 1.6006667+/-0.01963 for 0, 14 and 30 d post-treatment, respectively, P>0.05), and normal control group (1.440+/- 1.0641, P>0.05). RT enzyme activity in Chinese experimental mini-pigs was higher than in normal human control group (1.440+/-1.0641 U/mL, P<0.05), and not significantly different (P>0.05) when compared with the pig breeds except in the muscle supernatants. All the samples including muscle and liver cell supernatants from the Chinese mini-experimental pigs and the four domestic Chinese pig breeds contained PERVs. CONCLUSION: These results suggest that the risk of PERV infection through BALSS containing porcine liver cells without immunosuppressants may be quite low. Although there were PERVs in Chinese experimental mini-pigs and porcine liver cell culture suspensions, we did not find any evidence of persistent PERV infection in patients treated with this porcine hepatocyte-based bioartificial liver.

Adult↗

PubMed1999

A comparison of serum biochemical changes in two breeds of sheep (Red Masai and Dorper) experimentally infected with Fasciola gigantica.

Twelve Red Masai and 12 Dorper sheep aged between 6 and 9 months, were acquired from a fluke-free area and sheep of each breed divided into two equal groups of six. Each animal in one group of each breed was experimentally infected with 400 viable metacercariae of Fasciola gigantica. The other groups acted as uninfected controls. Blood samples were taken at weekly intervals for the determination of serum bilirubin, albumin, and gamma glutamyl transferase levels. Following the establishment of infection, albumin levels declined in both breeds of infected animals without any significant difference between the two breeds. However, serum bilirubin and gamma glutamyl transferase (GGT) in the infected animals were elevated significantly more in the Dorper than in the Red Masai sheep. Based on these findings, it would appear that Dorper sheep are more susceptible to the infection than Red Masai sheep.

Animals↗

PubMed1999

Androgen-metabolizing enzymes show region-specific changes across the breeding season in the brain of a wild songbird.

The Lapland longspur (Calcarius lapponicus) is an arctic-breeding songbird that shows rapid behavioral changes during a short breeding season. Changes in plasma testosterone (T) in the spring are correlated with singing but not territorial aggression in males. Also, T treatment increases song but not aggression in this species. In contrast, in temperate-zone breeders, song and aggression are highly correlated, and both increase after T treatment. We asked whether regional or temporal differences in androgen-metabolizing enzymes in the longspur brain explain hormone-behavior patterns in this species. We measured the activities of aromatase, 5alpha-reductase and 5beta-reductase in free-living longspur males. Aromatase and 5alpha-reductase convert T into the active steroids 17beta-estradiol (E(2)) and 5alpha-dihydrotestosterone (5alpha-DHT), respectively. 5beta-Reductase deactivates T via conversion to 5beta-DHT, an inactive steroid. We examined seven brain regions at three stages in the breeding season. Overall, aromatase activity was high in the hypothalamus, hippocampus, and ventromedial telencephalon (containing nucleus taeniae, the avian homologue to the amygdala). 5beta-Reductase activity was high throughout the telencephalon. Activities of all three enzymes changed over time in a region-specific manner. In particular, aromatase activity in the rostral hypothalamus was decreased late in the breeding season, which may explain why T treatment at this time does not increase aggression. Changes in 5beta-reductase do not explain the effects of plasma T on aggressive behavior.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

PubMed1996

[The state of in vitro breeding of lice and fleas]

Laboratory breeding of lice, fleas and other bloodsucking arthropods is necessary for developing and testing the efficacy of new drugs and alternative arthropod control methods. They are necessary to investigate their role as vectors of pathogens and to develop methods for diagnosis and therapy of arthropod caused or transmitted diseases. To date, it is not possible to replace rabbits as natural blood sources for breeding lice colonies (Pediculus spp.). But on the base of the knowledge about lice feeding and about in vitro-breeding of other arthropods it would be possible to develop an in vitro-feeding method for lice. For about three years an equipment is available in the USA for in vitro-breeding of cat fleas (Ctenocephalides felis). Using this so called "Artificial dog" it would be possible to replace numerous of cats used as hosts of laboratory flea colonies in pharmaceutical companies and other research laboratories

Journal Article↗

PubMed1975

[A.I. in pigs: breeding efficiency of one and two inseminations per heat (author's transl.)].

Breeding efficiency as expressed by the 30-60 days non-return percentage by one and two inseminations per heat was compared. Sows and gilts in a good heat (heat detection by stockmen) received only one insemination per heat, whereas females with a moderate/weal heat received two inseminations with an interval of approx. 24 hours, provided they were still in heat at the 2nd visit. The results have been set out in the tables I and II. A total of 89.1 and 90.8 percent non-returns by one and two inseminations per heat have been obtained (table I). The difference of 1.7 percentage units in favour of two inseminations is significant, (P less than 0.001). A variation within technicians of percentage of one insemination per heat from 10-97 was found, table II. 11 technicians had significant better results with two inseminations, one technician with one insemination, and by the rest of technicians no significant differences were found between one and two inseminations per heat. It is concluded that: 1) By effective heat detection, the breeding efficiency which can be obtained by one insemination per heat, is only two percentage lower than the breeding efficiency obtained by two inseminations per heat. 2) This loss in breeding efficiency is probably compensated by the economical advantage of one insemination per heat.

Animals↗

PubMed1999

[Preliminary evaluation of xenotransplantation and utilization of native pig breeds in China].

OBJECTIVE: To evaluate the general situation of the native pig breeds and the relative present study conditions for better development of xenotransplantation in China. METHODS: By comparing the profits between the pigs and the non-human primates as the potential donors for xenotransplantation and emphasizing the source of the pigs as the organ donors from the transplantation studies, we analyzed the possible values of the native pig breeds as the donors. RESULTS: As one of the richest resources in the world, the species variation and relative genetic stability of Chinese native pig breeds could be the very valuable resources for xenotransplantation study and utilization. As a reverse, the xenotransplantation could provide opportunity for more economically and environmentally utilization of the pigs besides as the meat supply. CONCLUSION: As a very valuable and potential resource of organ donor, the native pig breeds of China might be noticed by the xenotransplantation colleagues in the world. It is necessary, to keep the balance among the risk vs. benefit and the protection vs. utilization of this valuable resource.

Animals↗

PubMed2002

Physico-chemical characteristics of breeding habitats of Anopheles dirus (Diptera:Culicidae) in Assam, India.

Larval ecology of Anopheles dirus, the main vector of forest malaria in north-eastern region of India, was studied in relation to physico-chemical characteristics of its breeding habitats in a rain forest area of Assam, India. Shady stream side pools, positive for the breeding of An. dirus, had significantly higher amounts of total hardness (P < 0.024) in comparison to negative pools of similar type. When compared with An. dirus negative breeding habitats, in hot-wet as well as in cool-dry seasons, An. dirus positive shady ground pools showed higher mean values of total alkalinity, hardness and chloride content, whereas lower pH, dissolved oxygen along with higher total alkalinity and hardness were possessed by An. dirus positive stream side pools. Specificity of breeding habitats of An. dirus in relation to its ecology has been discussed.

Animals↗

PubMed2003

[Genetic mechanisms of resistance and susceptibility to leukemia in Ayrshire and black pied cattle breeds determined by allelic distribution of gene Bola-DRB3].

In the herds of Ayrshire and Black Pied cattle breeds of Russian selection, comparative analysis of allelic distribution of BoLA-DRB3 was performed in animal groups with different status of persistent lymphocytosis (PL) caused by the bovine leukemia virus (BLV). Alleles were typed by PCR-RFLP. Different spectra of BoLA-DRB3 alleles mediating susceptibility and resistance to leukemia were detected in the studied breeds. The role of amino acid motives in beta 1 domain of BoLA-DRB3 antigens was confirmed: ER (in positions 70-71), in resistance to leukemia and VDTY and VDTV (75-78), in susceptibility to leukemia. The nucleotide sequence of allele BoLA-DRB3.2*7 with deletion of codon 65, which resulted in the changed conformation of the corresponding antigen molecule, was associated with resistance to PL. Cows of Black Pied and Ayrshire breeds with genotypes coding VDTY/VDTV (RR = 11.67, P = 0.014) and VDTY/VDTY (RR = 4.71, P = 0.022), respectively, were shown to be susceptible to PL. The role of heterozygosity level was demonstrated (estimated by BoLA-DRB3 alleles and by amino acid motives in positions 75-78 of the antigen) as an unspecific factor of resistance to PL. The lowest heterozygosity level by amino acid motives (75-78) was revealed in PL animals, for which sample inbreeding coefficients were detected: F = 0.324 and F = 0.084 in Ayrshire and Black Pied breeds, respectively.

Alleles↗

PubMed2003

Breeding performance of great tits (Parus major) along a gradient of heavy metal pollution.

The possible effects of heavy metal pollution on various breeding parameters of the great tit (Parus major) were studied at four study sites in a pollution gradient near a large nonferrous smelter in Belgium during three consecutive breeding seasons. Significantly more females interrupted their laying period near the pollution source than did females farther away. At the two most polluted sites, hatching success was significantly reduced compared to two lesser-polluted study sites. Overall breeding success was also significantly lower toward the factory complex. This lowered breeding success was caused not only by the decreased hatching success toward the pollution source but also by the significant difference in fledging success among sites. Although a clear relationship was observed between the exposure to heavy metal pollution and an impaired reproduction, not all reproductive parameters were affected. We found no significant differences in the onset of laying, clutch size, length of the incubation period, and the proportion of nests with low-quality eggs among sites. Although nest box occupancy was every year slightly lower toward the smelter compared to farther away, differences among study sites were never significant.

Animals↗

PubMed1975

Studies on the mucosubstances elaborated by female duct of a land pulmonate Semperula maculata in seasonal breeding-aestivation cycle.

With a view to augmenting the understanding of the mucosubstances elaborated by the epithelial gland cells in the female duct of stylommatophoran pulmonate snail in general and finding out the seasonal variations in them during the breeding seasonal cycle of the snails in particular, the female duct mucosubstances were investigated in detail employing recent well-established histochemical techniques. The results showed that the gland cells in the female duct elaborated mucosubstances consisting of neutral mucins, glycogen, weakly sulfated sulfomucins, strongly sulfated sulfomucins and sialomucins. The study of cellular sites of mucosubstance elaboration showed that there are five different types of cells, the first type elaborated neutral mucins, the second weakly sulfated sulfomucins, the third strongly sulfated sulfomucins, the fourth sialomucins and the fifth glycogen. The seasonal variations in the mucosubstances showed that the acidic mucosubstance elaboration begins just before the post-breeding period and reaches a maximum in the pre-breeding season. Cyclic variations not only in the amount of the different mucosubstances but also in the number of cells elaborating them were witnessed in seasonal breeding-aestivation cycle. Since the results appear to indicate that the stages in the maturation of female sex cells in the ovotestis and uterus are closely related to the secretory process of the glandular cells in the female duct in the seasonal reproductive cycle of these snails, the importance of the mucosubstances secreted by the gland cells in the female duct is discussed with reference to the reproductive physiology of the snails.

Animals↗