Supplementing rumen‐protected methionine to lactating multiparous dairy cows did not improve reproductive performance

There is evidence that supplementing methionine has positive effects on uterine environment, oocyte quality and embryo development in cattle. Thus, the objective of this study was to evaluate reproductive traits of cows supplemented with rumen‐protected methionine (RPM) during early to mid‐lactation in comparison with an untreated control group (CON). An additional focus was on the effect of puerperal diseases on reproductive performance parameters in RPM‐supplemented group MET and in CON. A total of 1,709 multiparous Holstein‐Friesian cows were enrolled in this field trial conducted on a commercial dairy farm in Slovakia. Cows were allocated at approximately 12 days post‐partum (dpp) to either CON or MET, the latter supplemented with 25.0 g–27.2 g RPM per cow per day incorporated into the total mixed ration (TMR) until leaving the study pen at approximately 140 dpp. The amount of RPM was calculated based on individual feed ingredients analysis and adjusted during the study period when TMR changed. Cows were monitored during the post‐partum period by vaginal examination (day 5 pp), measuring of beta‐hydroxybutyrate in blood (3, 5, and 8 dpp) and by vaginal examination, uterine cytology and measuring of back fat thickness by ultrasound (all at 31 ± 3 dpp). Compared with CON, cows supplemented with RPM did not show better reproduction performance parameters (first service submission rate, days to first service, conception risk, days open 140). Results from binary logistic regression model for the risk of conception showed that metritis had a significant effect, but the supplementation of methionine had not. Results of Cox regression analysis for the odds of conception within 140 dpp revealed only metritis and clinical endometritis as significant factors. In conclusion, supplementation of RPM had no beneficial effect on reproductive performance in this study farm compared with an untreated control group.     

Cover Image,Volume 16, Issue 1

The cover image, by Alexandra Keller et al., is based on the Original Article The JAK2/STAT5 signaling pathway as a potential therapeutic target in canine mastocytoma, DOI: 10.1111/vco.12311

     

Plasma interleukin-6 response is predictive for severity and mortality in canine systemic inflammatory response syndrome and sepsis

BACKGROUND: Sepsis is still a major cause of death in both human and veterinary medicine. Early diagnosis is essential for appropriate treatment. Identification of patients at risk for developing sepsis is already possible in human medicine through the measurement of plasma interleukin-6 (IL-6) levels. In veterinary medicine, however, this has been investigated only in canine experimental models. OBJECTIVES: The purpose of this study was to measure IL-6 plasma levels in dogs with naturally occurring systemic inflammatory response syndrome (SIRS) and sepsis and to analyze the value of IL-6 as a predictive parameter for severity and mortality. METHODS: Included in the study were 79 dogs that had been admitted to the small animal clinics of Munich and Berlin from July 2004 to July 2005 and that satisfied the diagnostic criteria for SIRS and sepsis as defined using established parameters. Measurement of plasma IL-6 levels on days 0, 1, and 2 was performed by the use of a colorimetric bioassay based on IL-6-dependent cell growth. RESULTS: Septic foci were identified in 43 patients (septic group), and 36 patients were enrolled in the SIRS group. The frequency of positive blood cultures was 11%. The overall mortality rate was 48%. Higher plasma IL-6 levels on the day of admission were significantly correlated with a more severe degree of disease, increased mortality rate, and earlier fatality. CONCLUSIONS: Plasma IL-6 concentration is predictive of outcome in canine SIRS and sepsis and may be a valuable laboratory parameter for assessing critically ill dogs.     

Simultaneous application of the vascular endothelial growth factor (VEGF) receptor inhibitor PTK787/ZK 222584 and ionizing radiation does not further reduce the growth of canine oral melanoma xenografts in nude mice

PTK787/ZK 222584 is an inhibitor of the vascular endothelial growth factor (VEGF) receptor tyrosine kinases. In this study, the effectiveness of PTK787/ZK 222584 and radiation on canine oral melanoma xenografts was assessed. Xenografts were treated with radiotherapy (4x6Gy), or with PTK787/ZK 222584, or with a combination of both. Treatment efficacy was assessed using a tumour growth delay assay, serial power Doppler and pO(2) measurements during and after therapy. There was a significant growth delay for the group treated with radiation alone and for the combined treatment group. However, tumour growth delay was similar in both groups. Tumours were hypoxic before irradiation and no significant re-oxygenation occurred during therapy. In all tumours, vascularity and perfusion were significantly lower at the end of the study but no significant differences in perfusion, vascularity and oxygenation status were observed between and within treatment groups. The combination of PTK787/ZK 222584 and radiotherapy did not perform better than radiotherapy alone in this model.     

Estimating Rainy Season Nitrous Oxide and Methane Fluxes Across Forest and Pasture Landscapes in Costa Rica

The objectives of this research were to estimate exchanges of CH4 and N2O, both radiatively active gases, between soil and atmosphere on hilltop, slope and swale hillslope positions of northeastern Costa Rica; and to assess the importance of accounting for topography in making areal estimates across hilly terrain. Emission rates from soils were measured during the rainy season on three hillslope positions of both actively grazed pastures and primary forests. Emission rates from pasture and forest sites were significantly different for both gases. Differences between slope positions, though notable, were not significantly different for CH4, but were significantly different for N2O. The forest landscape was partitioned with GIS methods into hilltop, slope and swale topographic positions. The calculated areas for each of these were multiplied by their respective emission rates to calculate overall flux from the entire forested area of 618 ha. Nitrous oxide flux ranged from 16,181 to 17,100 g N d-1. Similarly, CH4 flux ranged from -6,201 to -6,658 g CH4d-1. Errors associated with both estimating mean emission rates for each hillslope position and judgmental errors in partitioning the landscape into hillslope positional classes are important to making landscape-scale estimates of flux.     

Horse vision and an explanation for the visual behaviour originally explained by the 'ramp retina'.

Here we provide confirmation that the 'ramp retina' of the horse, once thought to result in head rotating visual behaviour, does not exist. We found a 9% variation in axial length of the eye between the streak region and the dorsal periphery. However, the difference was in the opposite direction to that proposed for the 'ramp retina'. Furthermore, acuity in the narrow, intense visual streak in the inferior retina is 16.5 cycles per degree compared with 2.7 cycles per degree in the periphery. Therefore, it is improbable that the horse rotates its head to focus onto the peripheral retina. Rather, the horse rotates the nose up high to observe distant objects because binocular overlap is oriented down the nose, with a blind area directly in front of the forehead.     

The acquisition of cadmium by Lupinus albus L., Lupinus angustifolius L., and Lolium multiflorum Lam.

Das Cadmiumaneignungsvermögen von Lupinus albus L., Lupinus angustifolius L. und Lolium multiflorum Lam. Mehrere Pflanzenarten mobilisieren Bodenphosphate (P) und Kationen wie Fe und Al durch die Exsudation organischer Anionen und Protonen. Deshalb untersuchten wir das Cd‐Aneignungsver‐mögen von P‐, Fe‐, Al‐mobilisierenden Arten (Lupinus albus L., Lupinus angustifolius L.) im Vergleich zu einer nicht mobili‐sierenden Pflanzenart (Lolium multiflorum Lam.). Die Pflanzen wuchsen in zwei stark unterschiedlichen Böden (saurer Humuspodsol, karbonathaltiger Lössunterboden). Die Cd‐Aufnahme in die Sprosse war bei Weidelgras 5 bis 10 mal höher als bei Blauen bzw. Weißen Lupinen. Dieses Ergebnis hat mehrere Ursachen: 1. Das Wurzellängen/Sprossmasseverhältnis des Weidelgrases ist 2—3 mal größer als das der Lupinenpflanzen. 2. Bei Weidelgras wird ein größerer Teil des aufgenommenen Cd in die Sprosse verlagert. 3. Die Cd‐Aufnahme bei Lupinen ist im sauren Boden (Podsol) und bei P‐Mangel auch im Kalkboden niedriger als bei Weidelgras. Während im Podsol die Cd‐Konzentration der Bodenlösung unter Lupine geringer war als in der Kontrolle (Gefäße ohne Pflanzen), war sie im Kalkboden höher. Bei den Lupinen war der Efflux organischer Säureanionen, vor allem Citrat und Malat, um den Faktor 10—100 höher als bei Weidelgras. Diese Exsudation kann zu einer hohen Cd‐Komplexierung, insbesondere durch Citrat, in der Rhizosphärenbodenlösung führen (˜ 85%). Diese Ergebenisse deuten darauf hin, dass das komplexierte Cd von den Wurzeln schlechter aufgenommen wird als das freie Cd.     

Hygiene-Eliciting Brood Semiochemicals as a Tool for Assaying Honey Bee (Hymenoptera: Apidae) Colony Resistance to Varroa (Mesostigmata: Varroidae)

Despite numerous interventions, the ectoparasitic mite Varroa (Varroa destructor Anderson and Trueman [Mesostigmata: Varroidae]) and the pathogens it vectors remain a primary threat to honey bee (Apis mellifera Linnaeus [Hymenoptera: Apidae]) health. Hygienic behavior, the ability to detect, uncap, and remove unhealthy brood from the colony, has been bred for selectively for over two decades and continues to be a promising avenue for improved Varroa management. Although hygienic behavior is expressed more in Varroa-resistant colonies, hygiene does not always confer resistance to Varroa. Additionally, existing Varroa resistance selection methods trade efficacy for efficiency, because those achieving the highest levels of Varroa resistance can be time-consuming, and thus expensive and impractical for apicultural use. Here, we tested the hypothesis that hygienic response to a mixture of semiochemicals associated with Varroa-infested honey bee brood can serve as an improved tool for predicting colony-level Varroa resistance. In support of our hypothesis, we demonstrated that a mixture of the compounds (Z)-10-tritriacontene, (Z)-8-hentriacontene, (Z)-8-heptadecene, and (Z)-6-pentadecene triggers hygienic behavior in a two-hour assay, and that high-performing colonies (hygienic response to ≥60% of treated cells) have significantly lower Varroa infestations, remove significantly more introduced Varroa, and are significantly more likely to survive the winter compared to low-performing colonies (hygienic response to <60% of treated cells). We discuss the relative efficacy and efficiency of this assay for facilitating apiary management decisions and selection of Varroa-resistant honey bees, as well as the relevance of these findings to honey bee health, pollination services, and social insect communication.