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101.
SUMMARY The paper describes a program to import and breed black rhinoceros ex situ at Western Plains Zoo in Australia. Nine rhinoceros (7 females and 2 males) captured in 1992 in Chete National Park, Zimbabwe, were transported to Australia via Cocos Island. The veterinary treatment of the animals before and during quarantine in Zimbabwe and on Cocos (Keeling) Islands is described. Three animals died; an adult male on Cocos Islands and a juvenile male and an adult female at Western Plains Zoo, Dubbo, New South Wales. The juvenile male died as a result of trauma sustained shortly after arrival and the two adults after developing a severe hepatopathy. The group of 6 females and an additional 4 males imported from the USA in 1994 have adapted well to captivity and to the climate and environment of central west New South Wales.  相似文献   
102.
ABSTRACT A toxin, designated SnTox1, was partially purified from culture filtrates of isolate Sn2000 of Stagonospora nodorum, the causal agent of wheat leaf and glume blotch. The toxin showed selective action on several different wheat genotypes, indicating that it is a host-selective toxin (HST). The toxic activity was reduced when incubated at 50 degrees C and activity was eliminated when treated with proteinase K, suggesting that the HST is a protein. The synthetic hexaploid wheat W-7984 and hard red spring wheat Opata 85, the parents of the International Triticeae Mapping Initiative (ITMI) mapping population, were found to be sensitive and insensitive, respectively, to SnTox1. The ITMI mapping population was evaluated for toxin reaction and used to map the gene conditioning sensitivity. This gene, designated Snn1, mapped to the distal end of the short arm of chromosome 1B. The wheat cv. Chinese Spring (CS) and all CS nullisomic-tetrasomic lines were sensitive to the toxin, with the exception of N1BT1D. Insensitivity also was observed when the 1B chromosome of CS was substituted with the 1B chromosome of an insensitive accession of Triticum dicoccoides. In addition, a series of 1BS chromosome deletion lines were used to physically localize the sensitivity gene. Physical mapping indicated that Snn1 lies within a major gene-rich region on 1BS. This is the first report identifying a putative proteinaceous HST from S. nodorum and the chromosomal location of a host gene conferring sensitivity.  相似文献   
103.
The wheat disease tan (or yellow leaf) spot, caused by Pyrenophora tritici-repentis, was first described in the period 1934 to 1941 in Canada, India, and the United States. It was first noted in Australia in 1953 and only became a serious disease in the 1970s. The emergence of this disease has recently been linked to the acquisition by P. tritici-repentis of the ToxA gene from the wheat leaf and glume blotch pathogen, Stagonospora nodorum. ToxA encodes a host-specific toxin that interacts with the product of the wheat gene Tsn1. Interaction of ToxA with the dominant allele of Tsn1 causes host necrosis. P. tritici-repentis races lacking ToxA give minor indistinct lesions on wheat lines, whereas wheat lines expressing the recessive tsn1 are significantly less susceptible to the disease. Although the emergence and spread of tan spot had been attributed to the adoption of minimum tillage practices, we wished to test the alternative idea that the planting of Tsn1 wheat lines may have contributed to the establishment of the pathogen in Australia. To do this, wheat cultivars released in Australia from 1911 to 1986 were tested for their sensitivity to ToxA. Prior to 1941, 16% of wheat cultivars were ToxA-insensitive and hence, all other factors being equal, would be more resistant to the disease. Surprisingly, only one of the cultivars released since 1940 was ToxA insensitive, and the area planted to ToxA-insensitive cultivars varied from 0 to a maximum of only 14% in New South Wales. Thus, the majority of the cultivars were ToxA-sensitive both before and during the period of emergence and spread of the disease. We therefore conclude that the spread of P. tritici-repentis in Australia cannot be causally linked to the deployment of ToxA-sensitive cultivars.  相似文献   
104.
Twelve cats were vaccinated at 8 and 11 weeks of age with a commercially available inactivated FeLV vaccine (Nobivac FeLV, Intervet/Schering-Plough Animal Health). Eleven cats served as age-matched, placebo-vaccinated controls. All cats were kept in isolation for 2 years after vaccination and were then challenged with virulent FeLV to evaluate vaccine efficacy and duration of immunity. Cats were monitored for 12 weeks after challenge for development of persistent viremia using a commercial FeLV p27 ELISA. Persistent viremia developed in all 11 (100%) of the control cats, whereas 10 of 12 (83%) vaccinated cats were fully protected from persistent viremia following challenge. The results demonstrate that the vaccine used in this study protects cats from persistent FeLV viremia for at least 2 years after vaccination.  相似文献   
105.
Ten released varieties and one hundred and eleven tetraploid (2n = 4x = 28, AABB) wheat accessions collected from different major wheat producing regions, consisting of totally 2904 entries were characterized for content of yellow pigment, gluten strength, thousand kernel weights, grain yield, percent of yellow berry, glumes color, awn color, seed color, beak shape and spike density. The objectives were to assess variation with respect to regions of origin, species and altitudinal classes and to study the interrelationships of the qualitative traits used for the study. The accessions and/or released varieties showed significant regional variation for all the traits used in the study, but clinal variation among altitudinal classes and species were significant (P ≤ 0.01) in 6 (60%) and 9 (90%) of the studied traits, respectively. The accessions revealed consistent variation (P ≤ 0.001) within both regions and altitudinal classes for all the traits used in the study. The sedimentation volume was positively correlated with content of yellow pigment, percent of yellow berry, thousand kernel weights, glumes color, awn color, beak shape, seed color and grain yield. The contents of yellow pigment was positively correlated with awn color, beak shape and grain yield, but negatively correlated with seed color and spike density. Generally wide variation was found in the germplasm. Particularly variation was high for the content of the yellow pigment as well as the gluten strength, which provides opportunities to be utilized for genetic improvement.  相似文献   
106.
This study compared incisional complications after ventral midline laparotomy using 2 absorbable suture materials for apposition of the linea alba in sheep. The linea alba of 93 yearling sheep was sutured by 3 veterinarians in a simple continuous pattern using either polyglactin 910 (PG910; group PG) or polydioxanone (PDS; group PD). A blinded observer assessed surgical sites at the time of suture removal. Multivariate logistic regression was used to assess the association between incisional complications and variables (suture material used, veterinarian, skin suture removal time). The odds of incisional complications did not vary significantly with the type of suture material used (P = 0.11), veterinarian (P = 0.61) or skin suture removal time (P = 0.36). Most incisional complications were cutaneous suture sinus formation. Either PG910 or PDS may be used for linea alba closure in sheep.  相似文献   
107.
Investigations conducted in the laboratory for comparing the efficacy of phosphine with that of mixtures of the gas plus carbon dioxide against diapause larvae ofTrogoderma granarium showed that addition of varying concentrations of CO2 (20, 50, 75 and 100%) to fixed PH3-concentrations had a negative influence on phosphine efficacy against diapause larvae of Khapra Beetle at 30°C for short exposure periods of 18 and 24 hours. On the other hand, it was found that for longer exposure periods of 48 and 72 hours, the addition of CO2 to phosphine induced significantly higher larval mortality than that by PH3 alone, whereby an additive effect was proved for mixtures contained PH3+75% and 100% CO2. The addition of 20% and 50% CO2 to PH3 at 20°C did not show any increase in larval mortalities of the mixtures for exposure periods between 24–96 hours. The larval mortalities obtained for an atmosphere contained 20 and 50% CO2 alone at 20 and 30°C was (0–6%) and (10–40%), respectively, after 10 days exposure period.  相似文献   
108.
Summary The wrapped flower character has been reported to inhibit out-crossing in pigeonpea in Australia. However, one of the wrapped flower lines gave an average of about 16% out-crossing at ICRISAT Center near Hyderabad, India. This level of out-crossing was not different from that in cultivars having normal (unwrapped) flowers. This suggests that the wrapped flower trait is not a dependable character for reducing out-crossing in pigeonpea.ICRISAT Journal Article No. 578.  相似文献   
109.
The objective of this study is to evaluate the reproductive efficiency in donors and recipient Mangalarga Marchador mares in commercial programmes of embryo transfer (ET) and the effects of some reproductive characteristics and ET methodology on conception rates in the recipient mares. A total of 1140 flushing procedures were performed and 830 embryos (72.8%) were recovered. There were no differences between the rates of embryonic recovery in the different breeding seasons (p > 0.05) and 92.8% of the recovered embryos were 8–9 days old. There was no difference in the embryonic recovery regarding the collection order from the first to the ninth embryo collection along the breeding season, as well as among mares inseminated during the foal heat or subsequent cycles (p > 0.05). Pregnancy rates observed in the total period of all reproductive seasons at 15, 30, 45 and 60 days of pregnancy were 73.4, 69.9, 66.7 and 64.5%, respectively. Differences in pregnancy rate and early embryonic loss rates were not observed between embryos transferred immediately after collection (66.8% and 13.5%) and embryos transported at room temperature for periods of <1 h (62.9% and 14.4%; p > 0.05). Pregnancy rates were higher when the interval between ovulations of donor and recipient mares remained between ?3 and ?2 days (p < 0.05), and the lowest rates were observed for intervals of ?6 days (p < 0.05) with intermediary values for intervals of ?1, 0 and +1 (p > 0.05). Embryonic loss rates, however, did not differ between intervals of ovulation’s synchronism between donor and recipient mares (p > 0.05). This flexibilization in the ovulatory synchronism between donor and recipient mares optimizes the use of recipient mares, thus reducing costs and facilitating management of horse breeding farms.  相似文献   
110.
Three experiments were conducted to evaluate oil source and peroxidation status (experiment 1) or peroxidized soybean oil (SO; experiments 2 and 3) on growth performance, oxidative stress, and digestibility of dietary ether extract (EE). In experiment 1, palm oil (PO), poultry fat (PF), canola oil (CO), and SO were evaluated, while in experiments 2 and 3, only SO was evaluated. Lipids were either an unheated control (CNT) or thermally processed at 90 °C for 72 hr, being added at 10%, 7.5%, or 3% of the diet in experiments 1, 2, and 3, respectively. In experiment 1, 288 pigs (body weight, BW, 6.1 kg) were fed 1 of 8 factorially arranged treatments with the first factor being lipid source (PO, PF, CO, and SO) and the second factor being peroxidation status (CNT or peroxidized). In experiment 2, 216 pigs (BW 5.8 kg) were fed 1 of 6 treatments consisting of 100%, 90%, 80%, 60%, 20%, and 0% CNT SO blended with 0%, 10%, 20%, 40%, 80%, and 100% peroxidized SO, respectively. In experiment 3, 72 pigs (BW 5.8 kg) were fed either CNT or peroxidized SO. Pigs were fed 21 d with feces collected on day 12 or 14 and pigs bled on day 12 blood collection. In experiment 1, an interaction between oil source and peroxidation status was observed for averaged daily gain (ADG) and average daily feed intake (ADFI; P = 0.10) which was due to no impact of feeding pigs peroxidized PO, PF, or SO on ADG or ADFI compared with feeding pigs CNT PO, PF, or SO, respectively; while pigs fed peroxidized CO resulted in reduced ADG and ADFI compared with pigs fed CNT CO. There was no interaction between oil source and peroxidation status, and no lipid source effect on gain to feed ratio (GF; P ≥ 0.84), but pigs fed the peroxidized lipids had a lower GF compared with pigs fed the CNT lipids (P = 0.09). In experiment 2, feeding pigs diets containing increasing levels of peroxidized SO resulted in reduced ADG (quadratic, P = 0.03), ADFI (linear, P = 0.01), and GF (quadratic, P = 0.01). In experiment 3, feeding peroxidized SO at 3% of the diet reduced ADG (P = 0.11) and ADFI (P = 0.13), with no observed change in GF (P = 0.62). Differences in plasma protein carbonyls, glutathione peroxidase, and vitamin E due to feeding peroxidized lipids were inconsistent across the 3 experiments. Digestibility of dietary EE was reduced in pigs fed peroxidized PO or SO (P = 0.01, experiment 1) and peroxidized SO in experiments 2 and 3 (P ≤ 0.02). In conclusion, the peroxidation status of dietary lipids consistently affects growth performance and EE digestibility but has a variable effect on measures of oxidative stress.  相似文献   
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