牛DES基因的SNPs检测

设计了6套引物对利木赞(Limousin)和娟姗(Jersey)两个牛品种杂交一代的3头公牛进行DES基因的PCR扩增和测序,除引物4外均获得扩增产物,并在引物1扩增产物的上、下游及引物2扩增产物的上游序列的非编码区中各发现一个SNP,分别为SNP1(A/G)、SNP2(C/T)和SNP3(T/G)。同时测得公牛1、2、3的SNP1、SNP2、SNP3的基因型分别为A/A、A/G、A/G,C/C、C/C、C/T,T/G、G/G、G/G。     

Myofibroblastic fibrosarcoma with multifocal osseous metaplasia at the site of equine influenza vaccination

We describe a fibrosarcoma in a 12-year-old Quarterhorse × Arabian gelding as a sequela to equine influenza vaccination. Shortly after the second vaccination, swelling at the site was noticed by the owner and it continued to increase in size over the following 6 months. Biopsy of the mass indicated a fibrosarcoma had developed at the vaccination site. It was approximately 20 cm in diameter and elevated well above the level of the skin. There was no clinical evidence of metastases to the lungs or local lymph nodes. Surgical resection of the mass was performed and the wound healed by first and second intention. Histopathological examination and immunohistochemical staining confirmed a myofibroblastic fibrosarcoma with multifocal osseous metaplasia. To the authors' knowledge, this is the first equine case of a vaccine-associated fibrosarcoma.     

Protection of sheep by vaccination against experimental challenge with Leptospira borgpetersenii serovar Hardjo and L. interrogans serovar Pomona

AIMS: To evaluate a multivalent leptospiral and clostridial vaccine for prevention of renal colonisation and urinary shedding in sheep, following experimental challenge with New Zealand strains of Leptospira borgpetersenii serovar Hardjo type Hardjobovis and L. interrogans serovar Pomona.

METHODS: Two separate but similarly designed studies were conducted. In both studies, Romney-cross lambs, aged 9–11 weeks, were randomly allocated to a vaccinated group and a control group. Vaccinated lambs each received two 1.5-mL S/C doses of a multivalent leptospiral and clostridial vaccine, 4 weeks apart, and animals in the control groups received the same dose of saline. Groups of 12 vaccinated and 12 control lambs were randomly selected in each study for challenge with serovars Hardjo or Pomona. Challenge was initiated 16 weeks following the second vaccination with three daily doses of live leptospires by intranasal and conjunctival routes. Following challenge, urine samples were collected weekly for 6 weeks, for dark field microscopy and leptospiral culture; 6 weeks after challenge the lambs were slaughtered and kidneys collected for leptospiral culture.

RESULTS: In lambs challenged with serovar Hardjo, 8/12 unvaccinated lambs had ≥1 urine or kidney sample that was positive for leptospires following culture, compared with 0/12 lambs in the vaccinated group (p=0.001). In lambs challenged with serovar Pomona, 9/12 unvaccinated lambs had ≥1 urine or kidney sample that was positive following culture, compared with 0/12 lambs in the vaccinated group (p<0.001). Prevention of renal colonisation and urinary shedding, expressed as the prevented fraction, was 100 (95% CI=61.7–100)% and 100 (95% CI=68.3–100)% against challenge with serovars Hardjo and Pomona, respectively, at 4 months after vaccination.

CONCLUSIONS AND CLINICAL RELEVANCE: Use of a multivalent leptospiral and clostridial vaccine demonstrated protection against challenge from New Zealand strains of serovars of Hardjo and Pomona 4 months after vaccination in lambs first vaccinated at 9–11 weeks of age. Further studies are required to assess the duration of immunity against challenge in sheep.     

Evidence that moxidectin is a greater risk factor than ivermectin in the development of resistance to macrocyclic lactones by Ostertagia spp in sheep in south eastern Australia

AIM: To determine associations between resistance of Ostertagia (= Teladorsagia) spp to macrocyclic lactone (ML) anthelmintics and history of use of anthelmintics, by type, on commercial sheep farms in temperate regions of southern South Australia and Victoria, Australia.

METHODS: Faecal egg count reduction tests (FECRTs) were conducted during a 2.5-year period (from August 2001 to January 2004) and records of the type of anthelmintic used in the 5 years preceding the FECRTs were collected from commercial sheep farms (n=103) in southern South Australia and Victoria, and data analysed retrospectively. ML resistance was defined as <95% reduction of Ostertagia spp 10–14 days after treatment with ivermectin (IVM), orally, at half the manufacturer's recommended dose rate. Use of anthelmintics in the preceding 5 and 10 years on each property was classified according to the nett number of years each of the following classes of drug had been used: IVM oral liquid (IVO), IVM controlled-release capsules (CRCs), abamectin (ABA), moxidectin (MOX) or a non-ML an- thelmintic. The prevalence of ML resistance, by property, was analysed for associations with prior use of anthelmintics.

RESULTS: Resistance by Ostertagia spp to ML anthelmintics was evident on 51/103 (49.5%) properties. The prevalence of resistance was lowest (23%) on properties on which MOX had not been used, and was significantly higher (64–77%) on properties on which MOX had been used for ≥2 of the preceding 5 years (p<0.001). In contrast, the prevalence of resistance was highest (70–74%) on the properties on which IVM, or IVM and/ or ABA, had not been used in the previous 5 years (on which the use of MOX was predominant), and was markedly lower (20– 42%) on properties that had used IVM or IVM and/or ABA for at least one of the preceding 5 years. Prevalence of resistance was higher for properties on which the only ML anthelmintic used was MOX (19/29=66%) than for those on which the only ML used was IVO (2/19=11%; p<0.001). Properties on which the only ML used was MOX were 2.72 times more likely to have resistance than properties on which the only ML used was IVO (95% confidence interval (CI) = 1.01–5.08).

CONCLUSION: Use of MOX for ≥2 of the preceding 5 years was associated with a higher prevalence of resistance to ML by Ostertagia spp on sheep farms in south eastern Australia than the use of IVO.     

Influence of Ovulation Status,Seasonality and Embryo Transfer Method on Development of Cloned Porcine Embryos

To improve pig cloning efficiency, the present study evaluated the effect of ovulation status, seasonality and embryo transfer (ET) method on in vivo development of cloned porcine embryos. Cloned embryos were transferred to surrogate mothers on the same day of somatic cell nuclear transfer. In pre‐ovulation stage (PO), pregnancy rate (PR) and delivery rate (DR) were 36.3% and 9.4%, respectively. In post‐ovulation stage, 22.7% PR and 2.1% DR were recorded (both PR and DR are significantly higher in PO). When ET was performed during winter (December–February), spring (March–May), summer (June–August) and autumn (September–November), the PRs were 13.4%, 37.3%, 24.6% and 51.0%, while DRs were 0%, 12.7%, 4.3% and 7.8%, respectively. The highest PRs were recorded in autumn groups. However, DRs were significantly lower in autumn (7.8%) group compared with spring (12.7%) group. The PR was the lowest and no piglets were born in winter group, which might be because of the effect of low temperature during ET. To overcome the low PR in winter group, 0.25 ml straws were used for ET to minimize exposure time of embryos to ambient temperature. The straw ET group showed significantly higher PR in the winter group (23. 9%) compared with the conventional catheter‐loading group (7.7%). We suggest that using PO recipient and ET in spring is the best condition for pig cloning. In addition, alternative method to reduce cold shock during ET in winter is necessary.     

Factors affecting dam passage and upstream distribution of adult Pacific lamprey in the interior Columbia River basin

Low dam passage rates of adult Pacific lamprey (Entosphenus tridentatus) during upstream spawning migration have been implicated in the species' steep decline in the interior Columbia River basin. In this 2000–2010 study, we used radiotelemetry to evaluate potential predictors of lamprey passage success at McNary Dam, located ~469 river kilometres (rkm) from the Pacific Ocean. The tagged population included 276 lampreys collected at McNary Dam and 53 collected at Bonneville Dam (rkm 235) that migrated to McNary Dam. McNary Dam passage efficiency was similar for the two samples, with multiyear estimates of 0.65 and 0.75, respectively. Larger‐bodied lampreys and those with earlier migration timing were more likely to return to McNary Dam after release, to pass the dam and to be detected upstream from McNary reservoir. Far more lampreys entered the upper Columbia River than the Snake River, suggesting that environmental cues (e.g., water discharge, temperature) or conspecific cues (e.g., pheromone concentrations) affect lamprey distribution above this large confluence. Overall, results indicate that Pacific lamprey passage success at barriers depends on a combination of individual lamprey traits plus seasonal and site‐specific effects on behaviour.     

Real-time landslide warning during heavy rainfall

A real-time system for issuing warnings of landslides during major storms is being developed for the San Francisco Bay region, California. The system is based on empirical and theoretical relations between rainfall and landslide initiation, geologic determination of areas susceptible to landslides, real-time monitoring of a regional network of telemetering rain gages, and National Weather Service precipitation forecasts. This system was used to issue warnings during the storms of 12 to 21 February 1986, which produced 800 millimeters of rainfall in the region. Although analysis after the storms suggests that modifications and additional development are needed, the system successfully predicted the times of major landslide events. It could be used as a prototype for systems in other landslide-prone regions.     

Early maritime economy and El Nino events at quebrada tacahuay, peru

The archaeological site of Quebrada Tacahuay, Peru, dates to 12,700 to 12,500 calibrated years before the present (10,770 to 10,530 carbon-14 years before the present). It contains some of the oldest evidence of maritime-based economic activity in the New World. Recovered materials include a hearth, lithic cutting tools and flakes, and abundant processed marine fauna, primarily seabirds and fish. Sediments below and above the occupation layer were probably generated by El Nino events, indicating that El Nino was active during the Pleistocene as well as during the early and middle Holocene.     

Monitoring the temporal changes in herbicide-resistant Amaranthus tuberculatus: a landscape-scale probability-based estimation in Iowa

Background

A landscape-scale probability-based sampling of Iowa soybean [Glycine max (L.) Merr.] fields was conducted in 2013 and 2019; Amaranthus tuberculatus [Moq.] J.D. Sauer seed was collected from 97 random geospatial selected fields. The objectives were to evaluate the prevalence and distribution of herbicide-resistant A. tuberculatus (waterhemp) in soybean fields and evaluate temporal changes over 6 years. Amaranthus tuberculatus seedlings were evaluated for resistance to imazethapyr, atrazine, glyphosate, lactofen and mesotrione at 1× and 4× label rates.

Results

Resistance to imazethapyr, glyphosate, lactofen and mesotrione at the 1× rate increased significantly from 2013 to 2019 and was found in 99%, 97%, 16% and 15% of Iowa A. tuberculatus populations in 2019, respectively. Resistance to atrazine at the 4× rate increased over time; atrazine resistance was found in 68% of populations in 2019. Three-way multiple herbicide-resistant A. tuberculatus was the most frequent and increased significantly to 4× rates from 16% in 2013 to 43% of populations in 2019. All A. tuberculatus populations resistant to HPPD-inhibitor herbicides also were resistant to atrazine.

Conclusion

To the best of our knowledge, this is the first probability-based study that presented evolution of A. tuberculatus herbicide resistance over time. The results demonstrated that imazethapyr, atrazine and glyphosate resistance in Iowa A. tuberculatus populations was frequent whereas resistance to lactofen and mesotrione was less frequent. Most Iowa A. tuberculatus populations evolved resistance to multiple sites of action over time. The results of our study are widely applicable given the similarities in weed management practices throughout the Midwest United States. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.