Relationships between body weight and milk yield during the early postpartum period and bull and technician and the reproductive performance of high producing dairy cows     

Santolaria P  López-Gatius F  Sánchez-Nadal JA  Yániz J 《The Journal of reproduction and development》2012,58(3):366-370

The aim of this study was to evaluate the effect of body weight (BW) change during the early postpartum period and BW on day 50 post partum on the subsequent expression of estrus and fertility at first insemination before day 90 post partum. The data were derived from 1036 postpartum cows reaching 90 days in milk. The following data were recorded for each animal: lactation number, daily milk production at day 50 post partum, calving date, days in milk at estrus and at AI, insemination date, insemination number, inseminating bull, AI technician and body weight at calving, at day 50 post partum and at AI. Of the 1036 cows registered, 817 (78.9%) showed first estrus before day 90 post partum and were inseminated. Using logistic regression procedures and based on the odds ratio a one unit (kg) increase in the daily milk production at day 50 post partum and a one unit (kg) decrease in the BW between calving and day 50 post partum were related to a 1.03-fold increase and a 0.97-fold decrease in the estrus expression rate before day 90 post partum, respectively. Of the 817 cows inseminated before day 90 post partum, 437 became pregnant (53.5%). A one unit increase in the BW at day 50 post partum produced a 1.003-fold increase in the early fertility rate. Pregnancy rate before day 90 was also influenced by the season at calving, bull providing semen and technician. In conclusion, the register of BW during the postpartum period may be a useful tool for evaluating the nutritional status and its relationship with the subsequent reproductive efficiency in dairy cows.  相似文献   

Post-fire salvage logging increases restoration costs in a Mediterranean mountain ecosystem     

Alexandro B. Leverkus  Carolina Puerta-Pi?ero  José Ramón Guzmán-álvarez  Javier Navarro  Jorge Castro 《New Forests》2012,43(5-6):601-613

Post-fire salvage logging (i.e. felling and removing burnt trees, often eliminating the remaining woody debris) is a practice routinely performed by forest managers worldwide. In Mediterranean-type ecosystems, salvage logging is considered a measure to reduce future reforestation costs, but this assumption remains largely untested. We made a cost analysis of different management schemes, addressing the immediate post-fire burnt-wood management as well as the costs and success of subsequent reforestation efforts. Two experimental 25-ha plots were established in a burnt pine reforestation of SE Spain, in which three replicates of three post-fire treatments were applied: non-intervention (NI), partial cut plus lopping (PCL; felling and lopping off the branches from most of the trees, leaving all biomass in situ), and salvage logging (SL). After 4?years, a mechanised reforestation was undertaken, and seedling mortality was monitored for 2?years. The cost of all management operations was recorded in situ, and the cost of re-planting the dead seedlings was estimated according to the expenses of previous reforestation. Initial cost of wood management was greatest in SL and zero in NI. Reforestation cost was highest in NI and lowest in SL, and seedling-mortality rates proved lowest in PCL (43?% vs. 51?% and 52?% in SL and NI, respectively). Considering all the post-fire management operations, salvage logging did not provide particular economic advantages for forest restoration, and had an overall cost of 3,436?±?340?€/ha. By contrast, NI and PCL reduced total restoration costs by 50 and 35?%, respectively, and PCL indeed promoted restoration success. We suggest that the full cost of management operations needs to be considered when evaluating the economic implications of post-fire salvage logging.  相似文献   

Increase in size and nitrogen concentration enhances seedling survival in Mediterranean plantations. Insights from an ecophysiological conceptual model of plant survival   总被引：3，自引：2，他引：1  

Pedro Villar-Salvador  Jaime Puértolas  Bárbara Cuesta  Juan L. Pe?uelas  Mercedes Uscola  Norberto Heredia-Guerrero  José M. Rey Benayas 《New Forests》2012,43(5-6):755-770

Reduction in size and tissue nutrient concentration is widely considered to increase seedling drought resistance in dry and oligotrophic plantation sites. However, much evidence indicates that increase in size and tissue nutrient concentration improves seedling survival in Mediterranean forest plantations. This suggests that the ecophysiological processes and functional attributes relevant for early seedling survival in Mediterranean climate must be reconsidered. We propose a ecophysiological conceptual model for seedling survival in Mediterranean-climate plantations to provide a physiological explanation of the frequent positive relationship between outplanting performance and seedling size and nutrient concentration. The model considers the physiological processes outlined in the plantation establishment model of Burdett (Can J For Res 20:415–427, 1990), but incorporates other physiological processes that drive seedling survival, such as N remobilization, carbohydrate storage and plant hydraulics. The model considers that seedling survival in Mediterranean climates is linked to high growth capacity during the wet season. The model is for container plants and is based on three main principles, (1) Mediterranean climates are not dry the entire year but usually have two seasons of contrasting water availability; (2) summer drought is the main cause of seedling mortality; in this context, deep and large roots is a key trait for avoiding lethal water stress; (3) attainment of large root systems in the dry season is promoted when seedlings have high growth during the wet season. High growth is achieved when seedlings can divert large amount of resources to support new root and shoot growth. Functional traits that confer high photosynthesis, nutrient remobilization capacity, and non-structural carbohydrate storage promote high growth. Increases in seedling size and nutrient concentration strongly affect these physiological processes. Traits that confer high drought resistance are of low value during the wet season because hinder growth capacity. We provide specific evidence to support the model and finally we discuss its implications and the factors that may alter the frequent increase in performance with increase in seedling size and tissue nutrient concentration.  相似文献   

Echinococcus multilocularis in dogs from two French endemic areas: no evidence of infection but hazardous deworming practices     

Umhang G  Raton V  Comte S  Hormaz V  Boucher JM  Combes B  Boué F 《Veterinary parasitology》2012,188(3-4):301-305

The life cycle of the zoonotic parasite Echinococcus multilocularis is predominantly sylvatic, involving foxes as definitive hosts infected by predation of rodents, the intermediate hosts. The North-Eastern French departments of Meuse and Haute-Sa?ne are highly endemic, with an estimated fox prevalence of 41% and 36% respectively. Although most of the parasites' biomass occurs in foxes, domestic dogs can also be infected, leading to a major risk of human infection due to the close proximity of dogs and owners. In the present study, dog faeces were collected after praziquantel treatment provided by veterinarians. In all, 860 faecal samples were collected throughout Meuse (n=493) and Haute-Sa?ne (n=367). Intestinal helminth eggs were isolated from the faeces using a flotation technique and observed by microscopy. Parasite species were identified in samples positive for taeniid eggs by sequence analysis after PCR amplification. To study the factors associated with infestation, each sample was linked to a questionnaire filled in by the dog owners. Taeniid eggs were observed in seven faecal samples (0.8%) but none of them were positive for E. multilocularis. Thus, the apparent prevalence of E. multilocularis in dog populations is lower than 1.00% for Haute-Sa?ne and lower than 0.75% for Meuse. In Haute-Sa?ne, a high proportion of dogs observed suspected preying on rodents were not dewormed monthly. In endemic areas, these dogs must be considered at risk of transmitting E. multilocularis to humans.  相似文献   

Ecological preferences of exophilic and endophilic ticks (Acari: Ixodidae) parasitizing wild carnivores in the Iberian Peninsula     

Sobrino R  Millán J  Oleaga A  Gortázar C  de la Fuente J  Ruiz-Fons F 《Veterinary parasitology》2012,184(2-4):248-257

Ticks parasitizing wild carnivores and the tick-borne pathogens (TBPs) that they transmit may affect domestic carnivores and humans. Thus, investigating the role of wild carnivores as tick hosts is of relevance for understanding the life cycle of ticks in natural foci and the epidemiology of TBPs shared with domestic animals and humans. Therefore, the main objective of this study was to determine the ixodid tick fauna of wild carnivores in Peninsular Spain and the environmental factors driving the risk of wild carnivores to be parasitized by ixodid ticks. We hypothesized that the adaptation of tick species to differing climatic conditions may be reflected in a similar parasitization risk of wild carnivores by ticks between bioclimatic regions in our study area. To test this, we surveyed ixodid ticks in wild carnivores in oceanic, continental-Mediterranean, and thermo-Mediterranean bioclimatic regions of Peninsular Spain. We analyzed the influence of environmental factors on the risk of wild carnivores to be parasitized by ticks by performing logistic regression models. Models were separately performed for exophilic and endophilic ticks under the expected differing influence of environmental conditions on their life cycle. We found differences in the composition of the tick community parasitizing wild carnivores from different bioclimatic regions. Modelling results partially confirmed our null hypothesis because bioclimatic region was not a relevant factor influencing the risk of wild carnivores to be parasitized by exophilic ticks. Bioclimatic region was however a factor driving the risk of wild carnivores to be parasitized by endophilic ticks. Spanish wild carnivores are hosts to a relevant number of tick species, some of them being potential vectors of pathogens causing serious animal and human diseases. Information provided herein can be of help to understand tick ecology in Spanish wildlife, the epidemiology of tick-borne diseases, and to prevent the risks of TBPs for wildlife, domestic animals, and humans.  相似文献   

Molecular and serological detection of Theileria equi and Babesia caballi in donkeys (Equus asinus) in Brazil     

Machado RZ  Toledo CZ  Teixeira MC  André MR  Freschi CR  Sampaio PH 《Veterinary parasitology》2012,186(3-4):461-465

Piroplasmosis in donkeys has been recognized as a serious problem of major economic importance, since the affected animals manifest loss of appetite and decreased working capacity. The present work is aimed at detecting infection or exposure of donkeys in S?o Paulo, Brazil to Theileria (T.) equi and Babesia (B.) caballi using molecular and serological approaches. EDTA-blood and serum samples were collected from 88 donkeys (Equus asinus). From 88 sampled donkeys, 65 (73.86%; 95% confidence interval, PI=63.41, 82.65) and 82 (93.2%; 95% confidence interval, PI=85.75, 97.46) animals showed IgG antibodies to T. equi (by ELISA) and B. caballi (by IFAT), respectively. Twenty-eight (31.81%; 95% confidence interval, PI=22.3, 42.61) and 18 (20.45%; 95% confidence interval, PI=12.6, 30.39) donkeys were positive to T. equi and B. caballi nested PCR assays, respectively. The results indicated that T. equi and B. caballi are prevalent among donkeys in Brazil.  相似文献   

A new type of pterocarpanquinone that affects Toxoplasma gondii tachyzoites in vitro     

Portes Jde A  Netto CD  da Silva AJ  Costa PR  DaMatta RA  dos Santos TA  De Souza W  Seabra SH 《Veterinary parasitology》2012,186(3-4):261-269

Toxoplasma gondii, the agent of Toxoplasmosis, is an obligate intracellular protozoan able to infect a wide range of vertebrate cells, including nonprofessional and professional phagocytes. Therefore, drugs must have intracellular activities in order to control this parasite. The most common therapy for Toxoplasmosis is the combination of sulfadiazine and pyrimethamine. This treatment is associated with adverse reactions, thus, the development of new drugs is necessary. In previous studies, naphthoquinone derivatives showed anti-cancer activity functioning as agents capable of acting on groups of DNA, preventing cancer cells duplication. These derivatives also display anti-parasitic activity against Plasmodium falciparum and Leishmania amazonensis. The derivative pterocarpanquinone tested in this work resulted from the molecular hybridization between pterocarpans and naphtoquinone that presents anti-tumoral and anti-parasitic activities of lapachol. The aim of this work was to determine if this derivative is able to change T. gondii growth within LLC-MK2 cells. The drug did not arrest host cell growth, but was able to decrease the infection index of T. gondii with an IC(50) of 2.5 μM. Scanning and transmission electron microscopy analysis showed morphological changes of parasites including membrane damage. The parasite that survived tended to encyst as seen by Dolichos biflorus lectin staining and Bag-1 expression. These results suggest that pterocarpanquinones are drugs potentially important for the killing and encystment of T. gondii.  相似文献   

Enrofloxacin is able to control Toxoplasma gondii infection in both in vitro and in vivo experimental models     

Barbosa BF  Gomes AO  Ferro EA  Napolitano DR  Mineo JR  Silva NM 《Veterinary parasitology》2012,187(1-2):44-52

Currently, toxoplasmosis is treated with sulfadiazine and pyrimethamine. However, this treatment presents several adverse side effects; thus, there is a critical need for the development and evaluation of new drugs, which do not present the same problems of the standard therapy. Enrofloxacin is a fluoroquinolone antibiotic known to control infection against several bacteria in veterinary medicine. Recently, this drug has demonstrated protective effects against protozoan parasites such as Neospora caninum. The present study aimed to determine the effect of enrofloxacin in the control of Toxoplasma gondii infection. For this purpose, human foreskin fibroblast (HFF) cells were infected with T. gondii RH strain and treated with sulfadiazine, penicillin/streptomycin, pyrimethamine, or enrofloxacin. Following treatment, we analyzed the infection index, parasite intracellular proliferation and the number of plaques. Additionally, tissue parasitism and histological changes were investigated in the brain of Calomys callosus that were infected with T. gondii (ME49 strain) and treated with either sulfadiazine or enrofloxacin. Enrofloxacin was able to reduce the infection index, intracellular proliferation and the number of plaques in HFF cells infected by T. gondii in comparison with untreated or penicillin/streptomycin-treated ones. Enrofloxacin was more protective against T. gondii in HFF infected cells than sulfadiazine treatment (P<0.001). In addition, pyrimethamine, enrofloxacin or the associations of sulfadiazine plus pyrimethamine, enrofloxacin plus sulfadiazine or enrofloxacin plus pyrimethamine-treatments were able to reduce the plaque numbers in HFF cells infected by T. gondii when compared to medium, penicillin/streptomycin or sulfadiazine alone. In vivo experiments demonstrated that enrofloxacin diminished significantly the tissue parasitism as well as the inflammatory alterations in the brain of C. callosus infected with T. gondii when compared with untreated animals. Based on our findings, it can be concluded that enrofloxacin is a potential alternative drug for the treatment of toxoplasmosis.  相似文献   

Thymomas in rabbits: clinical evaluation, diagnosis, and treatment     

Künzel F  Hittmair KM  Hassan J  Dupré G  Russold E  Guija de Arespachochaga A  Fuchs-Baumgartinger A  Bilek A 《Journal of the American Animal Hospital Association》2012,48(2):97-104

Thymomas are rarely recorded in rabbits, and the literature includes comparatively few cases. Medical records were reviewed to identify all pet rabbits in which a mediastinal mass was diagnosed between Feb 2007 and Jan 2010. Signalment, history, clinical signs, diagnostic work-up (including laboratory data, diagnostic imaging, and ultrasound-guided fine-needle aspiration of the mediastinal mass), treatment modalities, survival time, and histologic findings were evaluated. Cytologic and/or histopathologic examinations revealed thymomas in all rabbits with mediastinal masses (n=13). Rabbits with thymomas showed clinical signs of dyspnea (76.9%), exercise intolerance (53.9%), and bilateral exophthalmos (46.2%). In seven rabbits the thymoma was removed surgically. Two rabbits were treated conservatively, and four rabbits were euthanized because of their poor clinical condition. The two rabbits that underwent surgery were euthanized 6 mo and 34 mo later. Mediastinal masses in rabbits appear to be more common than previously believed and consist primarily of thymomas rather than thymic lymphomas. Cytology of samples collected by ultrasound-guided fine-needle aspiration is an accurate diagnostic tool for the identification of thymomas in rabbits. Due to a high rate of perioperative mortality, intensive perioperative care and the provision of a low-stress environment are recommended for a successful thoracotomy.  相似文献   

Accuracy assessment and screening of a dairy herd with paratuberculosis by three different ELISAs     

Costanzo G  Pinedo FA  Mon ML  Viale M  Gil A  Illia MC  Gioffré A  Arese A  Travería G  Romano MI 《Veterinary microbiology》2012,156(1-2):183-188

Although the culture of Mycobacterium avium subsp. paratuberculosisis is the gold standard for the diagnosis of paratuberculosis, this bacterium is difficult to grow. In contrast, serological tests like ELISAs are inexpensive, rapid, and easy to perform. The aims of this study were to evaluate the accuracy of three different ELISAs: one with the commercial antigen PPA-3, another one with L5P (a recently described lipopentapeptide), and a third one with an in-house antigen whole cell lysates (WCL) of M. avium (MAA) strain D4ER (Study 1), and to compare them with other tests for paratuberculosis (PTB) diagnosis (Study 2). In Study 1, the sensitivities of the three ELISAs tested were 74.1%, 37% and 74.1%, respectively, whereas their specificities were 98.9%, 100% and 100%, respectively. In Study 2, we compared the three above-mentioned ELISAs with the intradermal reaction test using Avian PPD (PPDa) and fecal culture associated with Ziehl-Neelsen stain and PCR tests, in a dairy herd with 4.6% of cows with clinical signs of PTB. The results showed that fecal samples from 14 cows (16%) were culture-positive and that fecal samples from nine cows (10%) were PPDa-positive. Most of these animals (culture-positive and PPDa-positive) were detected as positive with any of the three ELISAs tested. Serological results showed that 31% of the animals were positive to ELISA-PPA-3, 17% to ELISA-L5P and 42.5% to ELISA-WCL. The combination of these three ELISAs identified 50.6% of the animals as positive in the infected herd. In particular, the results show that the locally developed ELISA seems to be useful for identifying many infected animals in a herd.  相似文献