Zinc deficiency in sheep and goats: three field cases     

D R Nelson  W A Wolff  D J Blodgett  B Luecke  R W Ely  J F Zachary 《Journal of the American Veterinary Medical Association》1984,184(12):1480-1485

Zinc deficiency was diagnosed in 2 flocks of sheep and a herd of goats. Alopecia and eating of wool were observed. Skin lesions were hyperkeratosis and parakeratosis. Abnormal hoof growth and a closed stance with arched back and bowed hindlimbs were seen. Anorexia, depression, and foot soreness diminished quickly after zinc supplementation. Skin lesions healed and hair and wool growth resumed. A cause for the deficiency could not be established.  相似文献   

Summer heat stress and reduced fertility in Holstein- Friesian cows in Arizona   总被引：1，自引：0，他引：1  

D E Monty  L K Wolff 《American journal of veterinary research》1974,35(12):1495-1500

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Variant serotypes of infectious bronchitis virus isolated from commercial layer and broiler chickens.   总被引：11，自引：0，他引：11  

J Gelb  J B Wolff  C A Moran 《Avian diseases》1991,35(1):82-87

Twenty infectious bronchitis virus (IBV) field isolates obtained from commercial layer and broiler chickens in 1987 and 1988 were serotyped using the virus-neutralization (VN) test. Six different previously unrecognized variant serotypes were identified from a total of seven isolates from layer chickens. Only two isolates, both from Maine, were the same variant serotype. Variant serotypes also were recovered from layer flocks in Illinois and Washington and the province of Ontario, Canada. Two different variants were isolated from the same multi-age layer complex in Connecticut. Only one of 13 broiler chicken isolates was found to be a new variant serotype, that being from birds reared in Delaware. Cross-protection studies in specific-pathogen-free chickens indicated that vaccines containing the Holland, L-1, or Connaught strains of Massachusetts (Mass) combined with Arkansas produced a broader spectrum of immunity against challenge with the layer variants than Mass (Holland) alone or Mass (L-1) + Connecticut. All vaccines tested produced solid immunity (greater than or equal to 80% protection) against the broiler variant virus.  相似文献   

Detection of embryonic mortality in cattle using sonography]     

N Wolff 《Tier?rztliche Praxis》1992,20(4):373-380

In 70 pregnant cattle the diameter of conceptus, the size of embryo and corpus luteum were estimated with a 5 MHz-linear array scanner on days 22, 25, 28, 35 and 42 (+/- 1 day) after insemination. Additionally, the milk progesterone level was determined. Embryonic mortality was found in 7 cases, in 3 cows on day 35, in 4 cows on day 42. The lack of embryonic heart beat was the first sign; later in pregnancy significant differences in sizes of conceptus and embryo compared with physiological pregnancies occurred. Membranes and bubble-like structures became visible in the lumen of the conceptus. The conceptus could be detected until the following oestrus, which began 8 to 42 days after embryonic death. The corpus luteum remained until proestrus. This correlated positively with the progesterone levels.  相似文献   

AAAS Popularization of Science Delegation Visits China     

Wolff K 《Science (New York, N.Y.)》1980,209(4453):264

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Bovine respiratory syncytial virus and bovine coronavirus in Swedish organic and conventional dairy herds     

Cecilia Wolff  Ulf Emanuelson  Anna Ohlson  Stefan Alenius  Nils Fall 《Acta veterinaria Scandinavica》2015,57(1)

Background

Infections with bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BoCV) are endemic to the cattle populations in most countries, causing respiratory and/or enteric disease. It has been demonstrated that herds can remain free from these infections for several years also in high prevalence areas. Organically managed (OM) dairy herds have been shown to have lower seroprevalence of both viruses compared to conventionally managed (CM) herds. The objective of this study was to challenge the hypothesis of a lower occurrence of BRSV and BoCV in OM compared to CM dairy herds.In November 2011, May 2012 and May 2013 milk samples from four homebred primiparous cows were collected in 75 to 65 OM and 69 to 62 CM herds. The antibody status regarding BRSV and BoCV was analysed with commercial indirect ELISAs. Herds were classified as positive if at least one individual sample was positive.

Results

The prevalence of positive herds ranged from 73.4% to 82.3% for BRSV and from 76.8% to 85.3% for BoCV among OM and CM herds, over the three sampling occasions. There was no statistically significant difference between OM and CM herds at any sampling occasion. The incidence risk of newly infected herds did not differ statistically between OM and CM herds at any sampling occasion, neither for BRSV nor for BoCV. The incidence of herds turning sero-negative between samplings corresponded to the incidence of newly infected. Bulk tank milk (BTM) samples were also sampled in the herds and analysed. Several herds were negative on individual samples but positive in BTM. Herd-level data on production, health and reproduction were retrieved from VÄXA Sweden and the study herds were representative of the source population.

Conclusion

There was no difference in prevalence of or incidence risk for BRSV or BoCV between Swedish OM and CM herds. Because the incidence of herds becoming seropositive was balanced by herds becoming seronegative it should be possible to lower the prevalence of these two infections among Swedish dairy cattle herds if biosecurity is improved.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-014-0091-x) contains supplementary material, which is available to authorized users.  相似文献   

Sulfated Steroid–Amino Acid Conjugates from the Irish Marine Sponge Polymastia boletiformis     

Vangelis Smyrniotopoulos  Margaret Rae  Sylvia Soldatou  Yuanqing Ding  Carsten W. Wolff  Grace McCormack  Christina M. Coleman  Daneel Ferreira  Deniz Tasdemir 《Marine drugs》2015,13(4):1632-1646

Antifungal bioactivity-guided fractionation of the organic extract of the sponge Polymastia boletiformis, collected from the west coast of Ireland, led to the isolation of two new sulfated steroid-amino acid conjugates (1 and 2). Extensive 1D and 2D NMR analyses in combination with quantum mechanical calculations of the electronic circular dichroism (ECD) spectra, optical rotation, and ¹³C chemical shifts were used to establish the chemical structures of 1 and 2. Both compounds exhibited moderate antifungal activity against Cladosporium cucumerinum, while compound 2 was also active against Candida albicans. Marine natural products containing steroidal and amino acid constituents are extremely rare in nature.  相似文献   

An assessment of the aquaculture potential of the tropical sponges Rhopaloeides odorabile and Coscinoderma sp.     

D. Louden  S. Whalan  E. Evans-Illidge  C. Wolff  R. de Nys   《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):57-67

Sponge aquaculture offers the opportunity to provide a sustainable supply of bath and industrial sponges and mitigate the environmental effects of over-harvesting. The potential to develop sponge aquaculture is diverse given the variety of sponge species. However, amenability to culture and the selection of appropriate culture methods are species specific and need to be determined to provide the platform for commercial success. In this study the survival (in situ and ex situ), growth rates (in situ), and recovery processes (ex situ) were measured for explants of two sponge aquaculture candidates, Rhopaloeides odorabile Thompson et al. and Coscinoderma sp. [Phylum Porifera: Order Dictyoceratida: Family Spongiidae], cultured in the Palm Islands Group of the central Great Barrier Reef. Sponge survival was dependent on the species, experiment duration, and method of culture. For both species the highest mortality occurred within days of excision of sponge material from parent stock, and mortalities were negligible after 78 days. After 78 days, R. odorabile had highest survival ex situ (75%) and lowest in situ (60%). In contrast, Coscinoderma sp. had the lowest survival ex situ (30%) and highest in situ (90%). The total growth of R. odorabile (146.0 ± 40.3%) and Coscinoderma sp. (195.9 ± 39.8%) was not significantly different over the 21 month experimental period, but was highly variable between explants from the same individual. Both species demonstrated initial size dependent growth rates with smaller explants growing fastest over the first 78 days. Explant recovery rates were rapid for both species with a protective layer of collagen forming over the surface within 24 h. This layer was replaced by pinacoderm between 3 and 41 days after excision as the subsurface tissue reorganised to recreate a functional surface for each species, including redevelopment of the aquiferous system within 41 days for R. odorabile. R. odorabile and Coscinoderma sp. both show potential for commercial aquaculture, however, further research is required to reduce initial mortality rates and the high variability in growth rates between explants.  相似文献   

Einige Bemerkungen zu dem Aufsatze „Über die Methoden neuzeitlicher Maßregeln gegen Insektenschäden im Walde”     

Prof. Dr. Wolff 《Journal of pest science》1926,2(5):60-61

Ohne Zusammenfassung  相似文献   

Reduced interannual rainfall variability in East Africa during the last ice age   总被引：1，自引：0，他引：1  

Wolff C  Haug GH  Timmermann A  Sinninghe Damsté JS  Brauer A  Sigman DM  Cane MA  Verschuren D 《Science (New York, N.Y.)》2011,333(6043):743-747

Interannual rainfall variations in equatorial East Africa are tightly linked to the El Ni?o Southern Oscillation (ENSO), with more rain and flooding during El Ni?o and droughts in La Ni?a years, both having severe impacts on human habitation and food security. Here we report evidence from an annually laminated lake sediment record from southeastern Kenya for interannual to centennial-scale changes in ENSO-related rainfall variability during the last three millennia and for reductions in both the mean rate and the variability of rainfall in East Africa during the Last Glacial period. Climate model simulations support forward extrapolation from these lake sediment data that future warming will intensify the interannual variability of East Africa's rainfall.  相似文献