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961.
M W Verstegen D Zwart W van der Hel B O Brouwer T Wensing 《Journal of animal science》1991,69(4):1667-1677
A study was conducted using 32 mature 22-kg West African Dwarf Goats to measure the effect of Trypanosoma vivax infection on energy and nitrogen metabolism. Sixteen goats were infected intravenously with 14 X 10(6) T. vivax. Sixteen control goats were sham-injected. Digestibility and metabolizability of energy and N balance were measured for each goat. Heat production and energy balances were measured per treatment group from 1 wk before infection to 6 wk after infection. Goats were fed alfalfa pellets (10% above maintenance). Treated goats had a reduced (P less than .05) packed cell volume (38 to 40% before infection vs 20 to 25% 6 wk after infection) and an increased (P less than .05) rectal temperature. Log parasitemia/ml was about 6.0 to 6.2. Parasitized goats showed increased urine creatinine excretion at wk 2 postinfection. After infection, feed intake was reduced (about 15%; P less than .05) and greater variability in intake was noted. Treated and control goats had similar N output and energy output in urine. Metabolizability of energy intake was similar at 42.7 vs 42.1% in treated vs control goats, respectively. Heat production in infected goats was increased by about 15%. Treated goats lost more weight and had a lower N balance than control goats (P less than .05). The calculated maintenance energy requirement for infected goats (464 kJ ME/kg.75) was 25% greater than for control goats (375 kJ ME/kg.75). 相似文献
962.
The purpose of this study was to compare the sexual performance of rams that differed in age (maturation) and sexual experience. Twenty-four ram lambs (8 mo of age) and 21 rams (20 mo of age) were individually exposed to four females in hormonally induced estrus for 30 min on five occasions, 7 d apart. Half (12) the ram lambs and nine of the yearlings were sexually naive at the start of testing (had been denied access to females since weaning); the remaining males were sexually experienced. The sexual performance of the virgin rams was poorer during the initial exposure to females than in subsequent tests, whereas the sexual behavior of the sexually experienced males did not change over the days of testing. Sexually naive ram lambs and rams exhibited an improvement in sexual performance between Tests 1 and 2; during Test 3 to 5 the sexual performance (ejaculations per test) of sexually naive and experienced rams was similar. The only effects of age (maturation) on sexual performance during the last three test days were a higher frequency of mounts without ejaculation plus mount attempts (P less than .03) and a greater number of mount interactions per ejaculation (P less than .02) by ram lambs. In conclusion, one or two relatively brief exposures to estrous females can bring the sexual performance of virgin rams up to levels comparable to that of experienced males. Also, ram lambs in good condition exhibit acceptable levels of sexual performance. 相似文献
963.
The objective of this experiment was to identify relationships among reproductive and uterine traits in mice having normal or crowded uterine conditions. Littermate females were randomly assigned to be either unilaterally ovariectomized (ULO) or to remain intact (C) and to be killed either 3 d after mating (PM) or 4 d after parturition (PP) in a 2 x 2 factorial design. Measurements taken were ovulation rate (OR) and uterine length (UL), wet weight (UWW), dry weight (UDW) and displacement (UDP) in PM females and number born (NB) and implantation rate (IMP) in PP females. Heritability estimates from full-sib correlations were .18, .01, .33, .04, .14, .47 and .06 for OR, IMP, NB, UL, UWW, UDW and UDP, respectively. Phenotypic correlations among uterine measurements were moderate to high and positive. Genetic correlations for C and ULO females for OR with NB were .62 and .73, respectively. Genetic correlations between C and ULO females were .53 for NB and 1.05 for OR. Genetic correlations of UL and UWW with NB were high for C (.70 and .59, respectively) and moderate for ULO (.47 and .36, respectively). Genetic correlations between NB and other uterine dimensions were lower. 相似文献
964.
Three rapid agglutination assays for the identification of Staphylococcus aureus Monostaph (Bionor A/S, Skien, Norway), Staphyslide-Test (BioMerieux, Lyon, France) and Staph-Rapid-Test (Roche, Basel, Switzerland), were compared. A total of 104 Gram-positive, catalase positive cocci were tested: Nineteen Staphylococcus reference strains comprising 15 spp. (4 strains were coagulase positive), and 7 Micrococcus reference strains comprising 4 spp.; 22 food isolates comprising 13 S. aureus, 8 coagulase positive Staphylococcus spp., and 1 Micrococcus sp.; 56 animal isolates comprising 11 S. aureus, 9 S. hyicus subsp. hyicus, 2 S. intermedius, 15 coagulase positive and 19 coagulase negative Staphylococcus spp. Totally 54 strains were coagulase positive. Considering agglutination of a coagulase positive strain as a correct identification, Monostaph, Staph-Rapid-Test, and Staphyslide-Test correctly identified 52 (96.3%), 47 (87.0%) and 48 (89.0%) of the coagulase positive staphylococci, respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test showed 1 (2.0%), 4 (8.0%) and 4 (8.0%) false positive reactions respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test gave 0 (0.0%), 6 (5.8%) and 7 (6.7%) non-interpretable reactions, respectively. Monostaph may be a good alternative to the tube-coagulase test for rapid and reliable identification of coagulase positive staphylococci from both food and veterinary sources. However, false negative reactions may occur with coagulase positive strains of S. hyicus subsp. hyicus and S. intermedius. 相似文献
965.
O Stigen 《Acta veterinaria Scandinavica》1991,32(2):197-203
The vertebral columns of 327 clinically normal, 12 to 18 months old dachshunds, were x-rayed. This sample represented 16.1% of all dachshunds registered with the Norwegian Kennel Club in the period 1986-1988. Calcified intervertebral discs were identified in 79 (24.2%) of the dogs and the number of calcified discs in each individual varied from 1 to 11 with a mean of 2.3. Calcified discs were estimated to occur in 23.5% of Norwegian dachshunds. The occurrence of calcified discs in standard-sized dachshunds was higher in the wirehaired variety (27.1%) than in the smoothcoated (16.4%) or longhaired (9.1%) varieties. However, within the longhaired variety the occurrence was higher in dwarfs and kaninchens (36.0%) than in standard-sized dachshunds (9.1%). Calcification was identified in all cervical, thoracic and lumbar intervertebral discs other than T1-2, and was found to be most frequent in the caudal thoracic vertebral column. 相似文献
966.
The post-thaw motility and the acrosome integrity of semen from 4 boars frozen with a programmable freezing machine, in mini (0.25 ml) and maxi (5 ml) plastic straws and in 10 x 5 cm Teflon FEP-plastic bags (0.12 mm thick, 5 ml), were compared. The freezing of the semen was monitored by way of thermo-couples placed in the straws and the bags. Three freezing programmes were used, namely A: from +5 degrees C, at a rate of 3 degrees C/min, to -6 degrees C, held for 1 min at -6 degrees C, and followed by a cooling rate of 20 degrees C/min to -100 degrees C; B: a similar curve except that there was no holding time at -6 degrees C and that the cooling rate was 30 degrees C/min, and C: from +5 degrees C to -100 degrees C, with a cooling rate of 35 degrees C/min, followed by storage in liquid N2. Despite the freezing curve assayed, both the mini-straws and the bags depicted much shorter freezing point plateaus as compared to the maxi-straws. Post-thaw sperm motility as well as the amount of normal apical ridges were equally significantly higher when semen was frozen in mini-straws or in bags than in maxi-straws. Significant differences in these post-thawing parameters were obtained between the freezing curves used. The stepwise freezing procedure A appeared as the best alternative for boar semen, considering this in vitro evaluation. 相似文献
967.
W O Nelson 《Journal of the American Veterinary Medical Association》1991,199(6):696-701
968.
Amantadine resistance among hemagglutinin subtype 5 strains of avian influenza virus 总被引:3,自引:0,他引:3
Several avian influenza virus strains of hemagglutinin subtype 5 were assayed for sensitivity to the antiviral drug amantadine. Most strains exhibited little sensitivity to the drug as measured by plaque reduction. The A/Chicken/Scotland/59 (CS59), however, was highly sensitive, making it easily distinguishable from the other H5 strains. Drug sensitivity of the viruses was also assayed in chicken embryos. The in ovo patterns of amantadine sensitivity differed from those detected in cell culture. The CS59 isolate could not be distinguished from all the other strains on the basis of its response to amantadine in ovo. Although amantadine protected chickens inoculated with CS59 from morbidity and mortality, drug-resistant viruses were readily isolated from the infected birds. As found with other amantadine-resistant variants, the structure of the matrix gene was altered in the resistant isolates. These results demonstrate that amantadine resistance is widespread among avian influenza viruses of the H5 subtype, that drug sensitivity in cell culture does not necessarily reflect responses to amantadine in ovo and in vivo, and, as previously found, amantadine-resistant derivatives of H5 strains may be isolated from birds protected by the drug. 相似文献
969.
O Distl 《Berliner und Münchener tier?rztliche Wochenschrift》1991,104(11):375-383
In totally 3740 cows of the breed German Brown Swiss distributed over 115 herds risk factors for the occurrence of diseases were analysed using a threshold model. Disease data were recorded by ten practitioners in southern Bavaria. The most frequent diseases were fertility disorders, followed by metabolic, udder and calving disorders. The influence of the herds could demonstrated clearly for all diseases analysed. The effect of the lactation number contributed significantly to the frequency of milk fever, mastitis, retained placenta, endometritis/metritis and ovary cysts. Heritability estimates vary between h2 = 0.5% and h2 = 4.2% with exception of anestrus/acyclia (h2 = 8.8%). With higher milk yield of cows the disease frequencies increase, especially fertility diseases. However, increasing herd milk yield is associated with decreasing disease frequencies. A depression of A.I.-parameters and an increase of culling rate caused by diseases could be observed. In the case of the occurrence of uterus- and ovary disorders days open are elongated by 58 days in comparison to cows without diseases. Recording of disease data for use in electronic data processing seems necessary, in order to diminish production diseases by breeding and herd control programmes. An important prerequisite in organization of disease data recording is an efficient cooperation between the veterinary practitioner, farmer, inseminator and the official milk recording organisation. 相似文献
970.
Silvio Peixoto Wilson Wasielesky Jr Fernando D'Incao Ronaldo O. Cavalli 《Journal of the World Aquaculture Society》2003,34(1):50-56
The reproduction of wild-caught Farfantepenaeus paulensis in captivity has been successfully achieved since 1983. However, year-round supply of wild broodstock is costly and unpredictable. This study compares the reproductive performance of animals of similar size (females from 32–33 g and males from 19–21 g) but from different sources: estuary-caught juveniles reared indoors for 9 mo and wild-caught adults from shallow coastal waters. Groups of 20 males and 30 unilaterally eyestalk-ablated females were maintained for 60 d in four maturation tanks under controlled environmental conditions. A higher number of eggs per spawning event (78,414 ± 34,491) and total egg production (4,469,600) were observed for the wild females. Nevertheless, captive females produced a higher number of nauplii (1,788,259) due to their higher percentage of fertilized spawns. Therefore, within the size range of this study, the reproductive performance of estuary-caught F. paulensis juveniles over-wintered indoors was found to be equivalent to that of wild-caught females from shallow coastal waters. 相似文献