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51.
Daniel Mageste de Almeida Marcos Inácio Marcondes Luciana Navajas Rennó Lívia Vieira de Barros Carla Heloísa Avelino Cabral Leandro Soares Martins David Esteban Contreras Marquez Felipe Vélez Saldarriaga Faider Alberto Castaño Villadiego Manuela Acevedo Cardozo Roman Maza Ortega Javier Enrique Garces Cardenas Virginia Lucia Neves Brandão Mário Fonseca Paulino 《Tropical animal health and production》2018,50(8):1771-1777
Beef cows’ milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows. Eighty Nellore cows were used, with initial weight of 516.0?±?1.0 kg. The experiment was a completely randomized factorial scheme, with 20 replications and four treatments (i.e., +?or ??pre-partum supplementation in combination with +?or ??post-partum supplementation): PRMM—1 kg of supplement/cow/day for 90 days pre-partum; MMPS—1 kg of supplement/cow/day for 90 days post-partum; PRPS—1 kg of supplement/cow/day for 90 days pre-partum and 90 days post-partum; and MM—only mineral mix ad libitum during pre- and post-partum. Milk was sampled on days 45, 135, and 225 post-partum (early, middle, and late lactation, respectively). No effects were observed of pre- and post-partum supplementation on milk yield (P?>?0.05). The afternoon/morning proportion of 0.45 in the early third of lactation was higher than other stages, which had a proportion of 0.41 (P?<?0.05). Post-partum supplementation increased milk protein in the morning and afternoon milking (P?<?0.05). There was also no effect of pre- and post-partum supplementation on afternoon-morning proportion other milk components (P?>?0.05). We conclude that estimating daily milk production of grazing beef cattle by multiplying a once daily milking amount times two is not accurate. Under the conditions of this study, proportion of total daily production represented by the ratio of afternoon/morning milking was 0.45 in early lactation (first third) and 0.41 in mid- and late lactation. 相似文献
52.
Daniele Soares Barroso Neves Robério Rodrigues Silva Fabiano Ferreira da Silva Laize Vieira Santos George Abreu Filho Sinvaldo Oliveira de Souza Marceliana da C. Santos Weder Jansen Rocha Ana Paula Gomes da Silva Mateus de Melo Lisboa Maria Magna Silva Pereira Venício Macedo Carvalho 《Tropical animal health and production》2018,50(7):1411-1416
The aim of this study was to evaluate the effect of increasing concentrate supplementation levels on the intake, nutrient digestibility, and performance of crossbred steers during the dry period of the year. The experiment was developed on Princesa do Mateiro farm, in the municipality of Ribeirão do Largo, located in the southwest region of Bahia State, Brazil. Forty uncastrated male crossbred (½ Holstein-Zebu) steers with an average body weight (BW) of 232.55?±?24.97 kg were distributed into four treatments in a completely randomized design with ten replicates. The animals were managed in an experimental area formed by Brachiaria brizantha cv. Marandu, in an intermittent grazing system. Treatments consisted of the following supplementation levels: 0.2% BW, with 60% crude protein (CP); 0.3% BW, with 40% CP; 0.4% BW, with 30% CP; and 0.5% BW, with 24% CP. The intakes of forage dry matter in kg/day and %BW and neutral detergent fiber corrected for ash and protein (NDFap) in %BW decreased linearly, whereas the intake of non-fibrous carbohydrates corrected for ash and protein in kg/day and average daily gain increased linearly. Therefore, the use of supplementation at 0.5% BW (24% crude protein) to provide gains of up to 0.500 kg/day is recommended for grazing steers during the post-weaning period in the dry season of the year. 相似文献
53.
Effect of body condition score and reuse of progesterone‐releasing intravaginal devices on conception rate following timed artificial insemination in Nelore cows
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LL Pereira AP Ferreira WG Vale LR Serique KAL Neves AC Morini BM Monteiro AHH Minervino 《Reproduction in domestic animals》2018,53(3):624-628
This study had the aim of investigating the efficiency of timed artificial insemination (TAI) through the progesterone‐releasing intravaginal device (PRID), used in new condition and for the second and third times in Nelore cows. The effects of device reuse and body condition score (BCS) on the conception rate (CR) were evaluated in 1,122 multiparous Nelore cows (mean BCS of 2.7 ± 0.4), which were randomly distributed into three groups that received new (n = 330), once (n = 439) and twice used (n = 353) PRID. Among the 1,122 females that underwent TAI, 573 became pregnant, thus representing an overall CR of 51.06%. Cows with BCS between 2.75 and 4.0 had greater (p < .0001) CR (69.75%) than cows with BSC of 2.0–2.5 (32.98%). It was observed that the CR through using PRID was 60.00%, 51.71% and 41.93% for new, once and twice used PRID, respectively, with difference between all groups (p < .0001). Under tropical conditions, animals with BCS greater than 2.5 had a higher CR, and the CR decreased proportionally with the number of times that the PRID had been used. 相似文献
54.
Pulchellin E (1) and gaillardin (2) were isolated from the aerial parts of Inula oculus-christi, along with the flavone hispidulin. The 13C-NMR chemical shifts of 1 and 2 are reported. 相似文献
55.
Human visceral leishmaniasis is an emergent/re-emergent parasitic zoonotic disease in Europe caused by Leishmania infantum, with domestic dog as its main reservoir host. This study presents the results of a canine epidemiological survey in a mediterranean region where human and canine leishmaniasis (CanL) are endemic - Portugal. The main goal was to identify risk factors, which can be relevant for Leishmania infection control. The national survey was carried out in January 2009 with a screening of 3974 dogs from all 18 districts of mainland Portugal. Direct Agglutination Test was used for the detection of anti-Leishmania antibodies in canine blood. An overall CanL true prevalence of 6.31% was observed. Apparent prevalence at district level ranged from 0.88% to 16.16%, with the highest prevalence in the interior regions. Identified risk factors for positivity were: dogs of 2 years and older (adjusted odds ratio OR=5.39); spending exclusively/most of the time outdoors (OR=2.51); origin from the interior of Portugal in comparison to littoral/coast districts (OR=2.51); not having long fur (OR=2.03); and being pure exotic (OR=1.67). The results confirm the leishmaniasis endemicity in Portugal and the dynamic character of prevalence as new foci emerged and old foci lost their importance. The dog's age, fur size, district and living outdoors as opposed to indoors were more important than dog breeds and insecticide treatment in the transmission of Leishmania infection. The future of CanL prevention and control rely on an integrated approach involving veterinarians, dog owners and health authorities in order to reduce the canine infection risk and consequently, the human zoonotic visceral leishmaniasis. 相似文献
56.
Carlos G. das Neves Julien Thiry Eystein Skjerve Nigel G. Yoccoz Espen Rimstad Etienne Thiry Morten Tryland 《Veterinary microbiology》2009,139(3-4):262-269
Alphaherpesviruses infect a wide range of animal species and cause diseases. Cervid herpesvirus 2 (CvHV-2) was originally isolated from reindeer in Finland but the impact of CvHV-2 infections on reindeer remains unclear. CvHV-2 infection could be partly responsible for calf losses as there are indications that it is associated with abortions and neonatal diseases. Previous serosurveys of reindeer (Rangifer tarandus tarandus) have shown that an alphaherpesvirus is circulating among reindeer in Norway. The aim of the present study was to determine the prevalence of CvHV-2 infection among reindeer in various herding districts in Finnmark, the largest reindeer area in Norway, and to identify factors associated with becoming infected with CvHV-2. A total of 3062 serum samples were tested using an ELISA and a sub-set of samples was further tested using a seroneutralization test. The ELISA revealed that 49% of samples were positive. Extrapolation of the results to the total population (111,350 animals; 66% of the Finnmark reindeer population) showed that the seroprevalence in the population was 48%. Seroprevalence varied from 7.6% to 90.7% between districts and was affected by age, weight and population density. ELISA-positive samples neutralized CvHV-2 at serum dilutions greater than those required for neutralization of bovine herpesvirus type 1. It is concluded that CvHV-2 is endemic throughout the reindeer herding districts of northern Norway. 相似文献
57.
Horak IG Nyangiwe N De Matos C Neves L 《The Onderstepoort journal of veterinary research》2009,76(3):263-276
The species and distribution of ticks infesting cattle, goats and dogs in the eastern region of the Eastern Cape Province, South Africa and Maputo Province, Mozambique were determined from collections made from these animals at 72 localities in the former region and 30 in the latter. Eleven ixodid and one argasid species were recovered in the Eastern Cape Province and 15 ixodid species in Maputo Province. The most common ticks infesting cattle and goats in both provinces were Amblyomma hebraeum, Rhipicephalus (Boophilus) microplus, Rhipicephalus appendiculatus and Rhipicephalus evertsi evertsi. The dominant species on dogs were Haemaphysalis elliptica and Rhipicephalus simus. The geographic distributions of the major species and some of the minor species in both regions were plotted. The partial or complete displacement of the indigenous tick Rhipicephalus (Boophilus) decoloratus by the introduced species R. (B.) microplus was a major feature of both surveys. 相似文献
58.
Ana Rita Neves Daniela Pereira Catarina Gonalves Joana Cardoso Eugnia Pinto Vitor Vasconcelos Madalena Pinto Emília Sousa Joana R. Almeida Honorina Cidade Marta Correia-da-Silva 《Marine drugs》2021,19(12)
Marine biofouling is a natural process that represents major economic, environmental, and health concerns. Some booster biocides have been used in biofouling control, however, they were found to accumulate in environmental compartments, showing negative effects on marine organisms. Therefore, it is urgent to develop new eco-friendly alternatives. Phenyl ketones, such as benzophenones and acetophenones, have been described as modulators of several biological activities, including antifouling activity (AF). In this work, acetophenones were combined with other chemical substrates through a 1,2,3-triazole ring, a strategy commonly used in Medicinal Chemistry. In our approach, a library of 14 new acetophenone–triazole hybrids was obtained through the copper(I)-catalyzed alkyne-azide cycloaddition “click” reaction. All of the synthesized compounds were evaluated against the settlement of a representative macrofouling species, Mytilus galloprovincialis, as well as on biofilm-forming marine microorganisms, including bacteria and fungi. The growth of the microalgae Navicula sp. was also evaluated after exposure to the most promising compounds. While compounds 6a, 7a, and 9a caused significant inhibition of the settlement of mussel larvae, compounds 3b, 4b, and 7b were able to inhibit Roseobacter litoralis bacterial biofilm growth. Interestingly, acetophenone 7a displayed activity against both mussel larvae and the microalgae Navicula sp., suggesting a complementary action of this compound against macro- and microfouling species. The most potent compounds (6a, 7a, and 9a) also showed to be less toxic to the non-target species Artemia salina than the biocide Econea®. Regarding both AF potency and ecotoxicity activity evaluation, acetophenones 7a and 9a were put forward in this work as promising eco-friendly AF agents. 相似文献
59.
M D Gomes Da Silva H J Chaves Das Neves 《Journal of agricultural and food chemistry》1999,47(11):4568-4573
The aroma compositions of Fragaria ananassa varieties are assessed by purge-and-trap high-resolution gas chromatography. Gas chromatography/mass spectrometry and gas chromatography/Fourier transform infrared spectroscopy allow the identification of 93 components from which 21 are for the first time described as constituents of strawberry aroma. Despite the complexity of the aroma, sensory properties are assigned to 40 components as perceived by three independent testers by application of a sniffing technique to the chromatographic effluent. The data are used for comparative sensory characterization of strawberry varieties by means of principal component analysis. 相似文献
60.