New indicator for classification of agroclimatic conditions for the cultivation of catch crops     

Vít Květoň  Michal Žák 《Archives of Agronomy and Soil Science》2017,63(2):250-260

The realization of the benefits of stubble catch crops (CC) cultivated after the harvest of the main crop requires the ability to produce substantial amounts of biomass before the onset of winter. The growth and biomass production of CC is primarily determined by the time period of sowing and weather conditions of the site. The construction of a new indicator of agroclimatic conditions for the cultivation of CC is described. This indicator includes the possible time period for CC sowing according to the harvest time of the preceding main crop, temperature, and water conditions for emergence and growth. The termination of growth due to low temperatures is considered. The assumptions used for the construction of the indicator, and the relationships to CC biomass were validated with data from field experiments. The resulting maps of regions in the Czech Republic with similar indicator values for three groups of CC differing in temperature demands are shown.  相似文献   

Supplementary feeding with thermally treated cereals in common carp (<Emphasis Type="Italic">Cyprinus carpio</Emphasis> L.) pond farming and its effects on water quality,nutrient budget and zooplankton and zoobenthos assemblages     

David Hlaváč  Maria Anton-Pardo  Jan Másílko  Pavel Hartman  Ján Regenda  Pavel Vejsada  Marek Baxa  Libor Pechar  Olga Valentová  Lucie Všetičková  Bořek Drozd  Zdeněk Adámek 《Aquaculture International》2016,24(6):1681-1697

To test the influence of supplementary feeding with thermally treated cereals on nutrient budget and environmental and biotic variables, three different treatments were applied in four experimental ponds: two with thermally treated cereals, one with raw cereal and a control with no supplementary feeding. Water parameters, zooplankton and zoobenthos were analysed from May to October over two consecutive years (2012 and 2013). In addition, nitrogen and phosphorus budgets were calculated as the difference between input (feed, stocked fish) and output (harvested fish). The results showed that type of supplementary feed had no influence on water quality, aside from water transparency. Ponds with added thermally treated cereal had significantly (P < 0.05) lower turbidity and suspended solids (and increased Secchi depth) compared with control. While no significant differences were observed in zooplankton assemblages between the experimental ponds and the control, macrozoobenthos density and biomass were considerably lower in the control pond. High seasonal fluctuations resulted in significant differences in density in 2012 only. The use of thermally treated cereal led to improved carp growth and nutrient budget, with an increase in carp yield and nutrient removal per hectare of pond surface. This result is a win–win situation with 10 % lower feed conversion ratio, increased profits and lower environmental impact.  相似文献   

Evaluation of the maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) diversity on the Archipelago of Madeira     

Miguel Ângelo A. Pinheiro de Carvalho  José Filipe Teixeira Ganança  Ivo Abreu  Nélia F. Sousa  Teresa M. Marques dos Santos  Maria Rita Clemente Vieira  Mario Motto 《Genetic Resources and Crop Evolution》2008,55(2):221-233

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Consumer interest in social sustainability issues of whitefish from capture fisheries in the north‐east Atlantic          下载免费PDF全文

Linda J L Veldhuizen  Ivo A van der Lans  Paul BM Berentsen  Imke J M de Boer  Eddie A M Bokkers 《Fish and Fisheries》2017,18(3):527-542

Capture fisheries in the north‐east Atlantic account for approximately 10% of all fish consumed from capture fisheries globally. The literature shows that consumers show considerable interest in social sustainability of products in general and of fish specifically. This interest, however, has not yet been investigated for fish from the north‐east Atlantic. The first objective of this study, therefore, was to investigate whether consumers are interested in social sustainability issues of whitefish from the north‐east Atlantic by determining preferences for four social sustainability issues with distinct benefits in relation to a known reference point (i.e. approach to overfishing). The second objective of this study was to determine to what degree case‐specific and general psychographic consumer characteristics explain preferences for these issues. Choice modelling results from an online survey among 457 Dutch consumers show that consumers have the strongest preference for the environmental sustainability issue approach to overfishing. In addition, results on the social sustainability issues showed that consumers prefer fish welfare over product quality, worker safety and local employment, indicating that in this case, consumers place animal benefits over personal, worker and community benefits. The case‐specific psychographic characteristic concern contributed most to explaining preferences for the environmental sustainability issue, whereas the general psychographic characteristic personal relevance contributed most to explaining preferences for the social sustainability issues. This result is likely explained by the principal focus on MSC certification in markets for fish products, which caused consumers to form opinions (e.g. concern) on overfishing, but not on social sustainability.  相似文献   

Half a century of genetic interaction between farmed and wild Atlantic salmon: Status of knowledge and unanswered questions          下载免费PDF全文

Kevin A Glover  Monica F Solberg  Phil McGinnity  Kjetil Hindar  Eric Verspoor  Mark W Coulson  Michael M Hansen  Hitoshi Araki  Øystein Skaala  Terje Svåsand 《Fish and Fisheries》2017,18(5):890-927

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Über die Kompostdüngung der Fichte in Waldbaumschulen     

Antonín Němec 《European Journal of Forest Research》1939,61(13):406-421

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快速生长小母猪较早进行人工授精后对繁殖性能的影响     

Rafael Kummer  Ivo Wentz  于古月  舒畅 《国外畜牧学(猪与禽)》2007,27(4):30-33

本试验的目的是研究提早具有较快生长速度(GR)的小母猪的配种时间,是否会降低其头3胎的繁殖性能、提高其1～3胎的淘汰率。试验选用568头Camborough 22小母猪,按配种时的体重和年龄分成3组:第一组(G1组)164头,生长速度高于等于700g/d,配种年龄低于210d;第二组(G2)165头,生长速度高于等于700g/d,配种年龄高于210d;第三组(G3)239头,生长速度低于700g/d,配种年龄高于210d。所有试验小母猪从150d起采取自由采食,并于其第二个或随后的发情期配种。第一胎,G2组小母猪的平均产仔数多于其它组(P<0.05)。然而,在对三胎产仔数进行分析后表明,各组小母猪在总产仔数(分别为11.6、12.3和11.7头)、分娩率(分别为87.1%、88.7%和和89.8%)和淘汰率(分别为30.2%、25.3%和28.2%)上没有显著差异(P>0.05)。因此,日龄在185～210d、体重为127kg的小母猪,可以在其第二个或随后的发情期中给予配种,且配种不会影响其头3胎的生产性能。  相似文献   

Risk factors for stillbirth and foetal mummification in four Brazilian swine herds   总被引：3，自引：0，他引：3  

Borges VF  Bernardi ML  Bortolozzo FP  Wentz I 《Preventive veterinary medicine》2005,70(3-4):165-176

The objective of this study was to identify the risk factors of stillbirth and foetal mummification in 565 farrowings of four commercial pig farms in Brazil. Stillborn piglets were observed in 31.3% of the litters and the stillborn risk was 5.6%. Mummified foetuses occurred in 42.1% of the litters and the mummification risk was 3.4%. The potential risk factors were included in multivariable logistic regression models as categories: herd (1–4); parity (1, 2–5 and >5); litter size (<10, 10–12 and >12 piglets); farrowing length (≤3 or >3 h); presence of mummified foetuses (yes or no); farrowing induction (yes or no); use of oxytocin (yes or no); use of vaginal palpation (yes or no); body condition score (<3, 3 and ≥4), and placental production index (PPI) (≤5 or >5) which was measured as the ratio of total foetal weight to total placental weight. Duration of farrowing and use of farrowing induction, oxytocin or vaginal palpation were not included in the model that investigated the risk factors of foetal mummification. Two models were used to investigate the risk factors of stillbirth, one with and the other without the inclusion of farrowing length. When compared to sows of parity 2–5, sows of parity >5 had 1.7- and 1.6-times higher odds (P < 0.05) for stillbirth in the models with and without the inclusion of farrowing length, respectively. In both models, sows with more than 12 piglets/litter had 3.6-times higher odds of stillbirth occurrence compared to sows with less than 10 piglets (P < 0.05). Sows with prolonged farrowing (>3 h) had 2.0-times higher odds of stillbirth occurrence than sows with short farrowing (P < 0.05). Sows with more than 12 piglets/litter had 14.5-times higher odds of mummification compared to sows with less than 10 piglets (P < 0.05). Sows of parities 1 and >5 had 3.5- and 2.0-times, respectively, higher odds of mummification in comparison to sows of parity 2–5 (P < 0.05). Sows with low PPI had 1.7-times higher odds of mummification compared to those with high PPI (P < 0.05). A large litter, a high-parity and a prolonged farrowing increased the risk of stillbirth. The probability of having a mummified foetus was increased in very young and older sows, when having a large litter and a litter with a less efficient placenta.  相似文献   

Economic aspects of the hybridisation programme in pig breeding in Czechoslovakia     

R. Šiler  Z. Poděbradský  O. Kvapil 《Livestock Production Science》1977,4(3):217-224

For the production of slaughter pigs under large-scale conditions, it is important to know the basic economic features of all links in the whole production chain and also the distribution of the total profit in relation to the amount of work involved in individual production sections. The economic evaluation of the production of the final hybrids through the various stages of the hybridisation programme is very valuable. This type of detailed economic examination has shown substantial room for improvement in the process and a large return on investment put into this area. This follows from the number of final hybrids (729) and from the total weight of slaughter pigs (80 190 kg) produced per sow in an elite herd.For example, under Czechoslovakian conditions, doubling the investments of sow breeding in elite herds (the increased initial price of sows, the increased intensity of breeding work connected with higher selection intensity, etc.) is fully compensated by an increase in the growth rate of hybrids during fattening of about 5 grams per pig per day (e.g. from 600 g to 605 g) without regard to changes in other performance characters.For the evaluation of individual performance characters, the profit functions were constructed and their use in the selection of possible combinations of crossing for final hybrid production was also shown.The objective knowledge of economic relations and functions in the production of slaughter pigs is thus becoming essential for the management of the whole pig industry.  相似文献   

A Study on the Predilection Sites of Trichinella spiralis Muscle Larvae in Experimentally Infected Foxes (Alopex lagopus,Vulpes vulpes)     

Chr. M. Kapel  Sv. Aa. Henriksen  H. H. Dietz  P. Henriksen  P. Nansen 《Acta veterinaria Scandinavica》1994,35(2):125

Kapel, Chr. M., Sv. Aa. Henriksen, H. H. Dietz, P. Henriksen, P. Nansen: A study on the predilection sites of Trichinella spiralis muscle larvae in experimentally infected foxes (Alopex lagopus, Vulpes vulpes). Acta vet. scand. 1994, 35, 125-132.–Studies were carried out on the predilection sites of Trichinella spiralis muscle larvae in experimentally infected arctic foxes (Alopex lagopus) and silver foxes (Vulpes vulpes) reared in cages. The highest number of larvae per gramme tissue was found in the muscles of the legs, eyes, diaphragm, and tongue. The 2 fox species showed no significant differences with regard to predilection sites.  相似文献