Estimation of daily milk yield of Nellore cows grazing tropical pastures     

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   

Comparison of temperature shock timing to induced artificial mitotic gynogenesis and androgenesis in common tench     

Joanna Nowosad  Dariusz Kucharczyk  Tomasz Liszewski  Katarzyna Targońska  Roman Kujawa 《Aquaculture International》2015,23(1):45-53

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Invalidity of three Palaearctic species of Triaenophorus tapeworms (Cestoda: Pseudophyllidea): evidence from morphometric analysis of scolex hooks     

Kuchta R  Vlcková R  Poddubnaya LG  Gustinelli A  Dzika E  Scholz T 《Folia parasitologica》2007,54(1):34-42

A comparative study of the scolex hook morphology of five species of tapeworms of the genus Triaenophorus Rudolphi, 1793 (Cestoda: Pseudophyllidea), parasites of pikes (Esox lucius L. and E. reichertii Dybowski) in the Palaearctic Region, was carried out. Measurements of scolex hooks of 81 plerocercoids and 492 adults from different hosts and regions were compared using basic statistics and forward stepwise linear discriminant analysis. The shape of the scolex and that of tridental hooks were found to be suitable only for differentiation of the taxa with a similar shape of hooks, i.e. Triaenophorus nodulosus (Pallas, 1781) from T. amurensis Kuperman, 1968, and T. crassus Forel, 1868 from T. meridionalis Kuperman, 1968 and T. orientalis Kuperman, 1968, respectively. In contrast, discriminant analysis did not enable reliable separation of specimens of individual taxa of these two morphological groups due to high intraspecific variability and overlaps between species. This was reflected in low classification efficiencies (average 83%) of all species of the T. crassus group, whereas all T. amurensis specimens were misidentified as T. nodulosus. The new data also considerably enlarge (up to twofold) the size range of the species described by Kuperman in 1968, which invalidates suitability of the most important discriminant characteristic, the width of the basal plate, for delimitation of Triaenophorus species. Based on the present data, all Kuperman's taxa are considered to represent only distinct geographical populations of T. nodulosus and T. crassus. As a result, T. anmurensis is synonymized with T. nodulosus, whereas T. orientalis is considered to be a synonym of T. crassus. Previous synonymisation of T. ineridionalis with T. crassus, first proposed by Dubinina (1987), is also accepted.  相似文献   

Flowers and fungi use scents to mimic each other     

Kaiser R 《Science (New York, N.Y.)》2006,311(5762):806-807

Some flowering plants mimic the scent and appearance of mushroom fruiting bodies. Fungi may also mimic flowers. In addition, infection of plants by certain fungi can direct the plant to develop nonfunctional floral-like structures that nonetheless primarily serve the reproductive advantage of the fungus. These various mimicries may serve to attract insects that in turn spread fungal spores or plant pollen, thus facilitating sexual reproduction of the cryptic organism.  相似文献   

Growth and phenology variation in progeny of Scots pine seed orchards and commercial seed stands     

Daniel J. Chmura  Roman Rożkowski  Władysław Chałupka 《European Journal of Forest Research》2012,131(4):1229-1243

Tree improvement in Poland has been most advanced for Scots pine, but existing seed orchards have not been progeny-tested yet. We examined variation in growth traits—tree height at ages 4 and 8 years, and diameter at age 13 years—in the common garden experiment testing open-pollinated progenies of 31 seed orchards and 5 commercial seed stands (referred to as populations) at 5 locations. We also examined bud burst phenology at two to five sites at three growing seasons. At one experimental site during the 5th growing season, we measured shoot growth rhythm on all populations. Similar measurements of shoot growth were done on a subset of populations during the 6th growing season together with the analysis of needle growth and foliar chemistry. We found significant variation among populations in growth traits, but also significant population × site (G × E) interactions. We used the regression approach and ecovalence analysis to examine populations’ performance stability. Most populations had average responsiveness to environment, and a set of least-responsive poor-growing populations contributed the most to the G × E interaction. Variation in bud burst phenology was associated with geographical distribution of tested progenies. The early bud-bursting populations originated from the north-eastern to north-central Poland, and a group of late bud-bursting populations originated mainly from the south-eastern region. Correlations between bud burst and growth traits were weak to medium and varied by site, but early bud-bursting populations tended to show stronger growth on height and diameter. We found significant differences among populations in final leader length, shoot elongation time and relative growth rate (RGR). However, RGR and shoot elongation time explained less than 30% of variation in leader length and were weakly correlated with tree height. Populations varied in needle length, specific leaf area and foliar nitrogen concentration, but time trends in these traits did not vary among populations or predefined groups of populations. Therefore, the analysis of growth rhythm or needle traits did not help resolve variation in tree growth to support selection decisions. Contrary to our expectation, progeny of seed orchards did not perform significantly better than that of commercial seed stands. This finding, however, should not be extrapolated beyond our set of populations. Nonetheless, the local seed sources were not always the best. From a selection standpoint, our results help culling the worst populations rather than selecting the best ones. Therefore, testing individual family progeny and genetic roguing of existing seed orchards is highly recommended.  相似文献   

Wnt/β-catenin signaling regulates telomerase in stem cells and cancer cells     

Hoffmeyer K  Raggioli A  Rudloff S  Anton R  Hierholzer A  Del Valle I  Hein K  Vogt R  Kemler R 《Science (New York, N.Y.)》2012,336(6088):1549-1554

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Dead-end (dnd) protein in fish—a review     

Baloch  Abdul Rasheed  Franěk  Roman  Saito  Taiju  Pšenička  Martin 《Fish physiology and biochemistry》2021,47(3):777-784

Fish Physiology and Biochemistry - Dead end (dnd) is a germ plasm-specific maternal RNA discovered in zebrafish and then in other vertebrates. Dnd protein is essential for migration and motility of...  相似文献   

Brief communication: rapid elimination of egg stickiness using sodium hypochlorite in wels catfish Silurus glanis     

Pšenička  Martin  Franěk  Roman 《Fish physiology and biochemistry》2021,47(3):681-685

Fish Physiology and Biochemistry - The wels catfish Silurus glanis is valuable fish for aquaculture. Its production relies mainly on artificial reproduction. One of the crucial steps determining...  相似文献   

Eradication of Rinderpest from Ethiopia     

Abraham  G.  Roman  Z.  Berhan  A.  Huluagerish  A. 《Tropical animal health and production》1998,30(5):269-272

Tropical Animal Health and Production -  相似文献   

Plant growth regulating properties of 1-amino-1-methylethylphosphonic acid and its derivatives     

Barbara Lejczak  Pawel Kafarski  Roman Gancarz 《Pest management science》1988,22(3):263-275

Seventeen derivatives of 1-amino-1-methylethylphosphonic acid were synthesised and evaluated for plant-growth-regulating activity using Cucumis sativus and Triticum aestivum. The tested compounds exerted either moderate herbicidal action or stimulated plant growth. The structure-activity relationships were similar to those observed earlier for the derivatives of 9-aminofluoren-9-ylphosphonic acids (phosphonic analogues of morphactins).  相似文献