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1.
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of...  相似文献   
2.
Integrated crop–livestock–forest is a promising strategy to improve soil quality. It comprises four different integrated farming systems: crop–livestock, crop–forest, forest–livestock and crop–livestock–forest. This work systematically reviewed studies about integrated crop–livestock–forest systems and soil quality. A total of 92 papers were retrieved from the Web of Science—Clarivate Analytics platform, and the following information was analysed: publication year, institution, region of the studied site, type of integrated system, soil type, tillage system, maximum soil depth and the soil quality indicators assessed. Most studies were published in the second half of the 2010s. Brazil is a prominent focus of research about soil quality and integrated crop–livestock–forest systems, with significant contribution from its central and southern regions. The Embrapa was the main publishing institution, present in over one‐third of the studies. Crop–livestock was the most common integrated system, Ferralsols was the most common soil group, and most of the studied soils were clayey. No tillage was the main tillage system. Most studies focused on the topsoil, assessing physical and/or chemical soil quality indicators. More emphasis on biological indicators of soil quality is required, as well as assessments integrating biological, physical and chemical indicators of soil quality. Future works should compare different integrated systems, including assessments deeper in the soil profile, especially in systems with the forest component, and also in sandy and silty soils. Soil quality indicators that have been rarely used should be further tested. Novel indicators should be added to better understand the promotion of soil quality by integrated crop–livestock–forest systems.  相似文献   
3.
SUMMARY: The activity of enzyme aldolase (ALD) was determined in the sera of Simmental young bulls, with the purpose to see whether there exists a relationship between the enzyme activity and fattening capacity and whether the ALD could be an indicator of the muscle quantity and protein content. Early ALD activity was correlated with slaughter weight and ADG in the last fattening month. The regression analysis suggests that young bulls with higher serum ALD acitivity at the start of the experiment had more total muscles and less bone in the analysed rib part. On the basis of ALD activity in the first fattening month it was possible to estimate protein and fat content in the MLD. ZUSAMMENFASSUNG: Fructose-1,6-biphosphat Aldolase beim Serum Simmentaler Jungbullen. Beziehung zwischen Mastf?higkeit, Muskelmenge und Proteingehalt Aldolase (ALD) Enzymt?tigkeit im Serum von Simmentaler Jungbullen wurden in Hinblick auf eine Beziehung mit Mastf?higkeit, Muskelmenge und Proteingehalt untersucht. Es zeigt sich eine Korrelation zwischen früher ALD Aktivit?t und Schlachtgewicht und Tageszuwachs im Endmastmonat. Regressionsanalyse ergab, da? Jungbullen mit h?herer ALD Aktivit?t bei Mastbeginn mehr Muskelanteil im m. longissimus dorsi und weniger Knochen besitzen. ALD Aktivit?t im ersten Mastmonat erlaubt Sch?tzung des Protein- und Fettgehalts im m. long, dorsi. RESUMEN: Fructosa 1,6-bifosfato aldolasa en el suero de los terneros simentales. Relatión con sus capacidades de ser cebados, su cantidad de músculos y el contenido de proteínas Con el fin de establecer la relación entre la actividad de enzimas y las capacidades durante el proceso de la ceba, asf como para precisar si el ALD puede servir como indicador de la cantidad de músculos y el contenido de proteinas, intentaba determinarse la actividad de los enzimas de aldolasa (ALD) en el suero de los terneros simentales. A base de la actividad indicial del ALD, es posible estimar el peso final de matadero y la crecencia diaria media durante el último mes de la ceba. Tras una análisis regresiva se ha probado que los terneros con una actividad mayor del ALD en el suero a principios del proceso de su ceba tienen más músculos en total en la parte de costillas y m. longissimus dorsi mientras que tienen menos huesos. A base de la actividad del ALD durante el primer mes de la ceba es posible estimar el contenido de proteinas y grasa en m. long, dorsi. RéSUMé: Fructose 1.6-biphosphate aldolase dans le sérum des taurillons de Simmental. Le rapport entre l'aptitude à l'angraissement, la proportion des muscles et la teneur en protéines On a déterminé l'activité de l'enzyme aldolase (ALD) dans le sérum des taurillons de Simmental afin de vérifier s'il existait un rapport entre l'activité des enzymes et l'aptitude à l'engraissement et si l'ALD pouvait être indicatrice de la proportion de muscles et de la teneur en protéines. A la base de l'activité initiale de l'ALD, il est possible d'évaluer le poids de la carcasse et le gain quotidien moyen au cours du dernier mois d'engrais. Par analyse régressive, il a été établi que les taurillons à l'activité supérieure de l'ALD dans le sérum avaient au début de l'engrais plus de muscles au total dans la région costale et le m. longissimus dorsi et moins d'os. A la base de l'activité de l'ALD au cours du premier mois d'engrais il est possible d'évaluer la teneur en protéines et en graisse dans le muscle longissimus dorsi.  相似文献   
4.
Two experiments were conducted to evaluate reduced supplementation frequencies for grazing beef cattle in rainy season. In experiment 1, evaluating the nutritional parameters, four rumen-cannulated Nellore bulls (BW = 410 kg) were used. In experiment 2, evaluating animal performance, 48 Nellore bulls (BW = 358 kg) were used. The treatments were as follows: mineral supplement (MS) alone and MS plus protein-energy supplement provided 3×, 5× and 7×/week. Supplementation frequency did not affect (P > 0.05) intake and digestibility. Average daily gain was greater (P < 0.001) to supplementation compared with MS. The supplementation 5×/week resulted in greater weight gain per hectare (9.24) and higher economic returns during the study period (1.64%) compared to other supplementations. Supplementation 5×/week increased animal performance and positively influenced economic returns.  相似文献   
5.
6.
Maize is arguably the most widely grown crop in the world, but it is often associated with one of its major insect pests, the European corn borer (ECB). The damage caused by this species to maize production is generally variable, but in many cases it is economically significant. This review paper provides an overview of the research findings on the natural plant defence mechanisms against ECB larvae published till now. What is resistance and how it is achieved, what is the chemical response of maize plants to insect feeding and how tolerance can be increased. A short introduction in breeding for resistance and a discussion if the mentioned traits can be used in conventional breeding in order to create maize hybrids less affected by ECB are given.  相似文献   
7.
The use of live animals for educational purposes is an old practice that is still employed in teaching and research institutions. However, there are several objections to this practice, whether for ethical or humanitarian reasons. Surgical techniques teaching using anatomical pieces and/or preserved cadavers promotes greater learning efficiency, provides exercise repetition and increases the confidence and satisfaction of the students when compared to the use of live animals. The current work aimed to analyse the feasibility of using fresh swine urinary bladder and small intestines (jejunum), obtained from slaughterhouses, fixed in 99.8% ethyl alcohol (EA) and preserved in sodium chloride hypersaturated solution (SCHS) at 30%, for 7, 14 and 21 days, as an alternative method for surgical skills training (SST). Swine viscera, fixed in EA and preserved in SCHS, presented a realistic appearance, absence of odour and maintained the viable morphological characteristics during the performance of the operative techniques. Preservation solutions had low cost, were easy to acquire and did not offers risks to human health. Therefore, urinary bladders and small intestines fixed in 99.8% EA for 30 days and maintained in 30% SCHS at different periods were demonstrated as a good viable option as a preservation method for surgical skills training.  相似文献   
8.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   
9.
Dehorning adult cattle is a surgical procedure causing distress of varying intensities that can be reflected in behavioural changes and alterations in plasma cortisol levels. Stress responses during the dehorning process were evaluated in 18 Red Pied cows. The cows were divided into 3 groups of six and kept in tie-stall housing. Those in the first group were dehorned under general anaesthesia (GA) induced by intravenous administration of xylazine and ketamine. The second group was dehorned under sedation and local anaesthesia (SLA) induced by intramuscular administration of xylazine and local anaesthesia with lidocaine. The third group was dehorned under local anaesthesia (LA) with lidocaine. Dehorning was performed with a foetotomy wire. Blood samples were taken 0.5 h before dehorning to determine cortisol levels, and, by means of a central venous catheter inserted into the jugular vein, during surgery at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7 and 8 h post-surgery. Concurrently, occurrence of stress behaviours was assessed. Cortisol levels were measured by enzyme immunoassay (EIA). The lowest mean peak levels of plasma cortisol (82.53 +/- 6.04 nmol l(-1)), the most rapid return of plasma cortisol levels to baseline values (1.92 +/- 1.11 h), and the lowest occurrence of stress behaviours (2.38 +/- 5.83%) were noted in the SLA group. The highest mean peak levels plasma cortisol (113.86 +/- 25.65 nmol l(-1)), the slowest return of plasma cortisol levels to baseline values (3.83 +/- 2.18 h) and the most frequent occurrence of stress behaviours (65.48 +/- 28.72%) were observed in the LA group. There were significant differences between the SLA and LA groups in peak plasma cortisol levels (p = 0.011) and in occurrence of stress behaviours (p = 0.003). Sedation induced by intramuscular administration of xylazine in conjunction with local anaesthesia with lidocaine is considered the most suitable method of anaesthesia when dehorning adult cattle. Local anaesthesia with lidocaine alone was least suitable.  相似文献   
10.
Surprisingly few commercial ELISAs are available for the detection of Toxoplasma gondii infection in animals, and none for use in sheep have been evaluated. We thus compared the Bommeli Diagnostics ELISA Toxotest for the detection of T. gondii antibodies in ruminants with the reference modified agglutination test (MAT) in a series of 180 sheep sera. ELISA results were analysed at two cut-off levels (30%, comprising both weakly positive and positive results, and 100%, comprising only positive results), and compared with MAT at three cut-off levels (titre of 1 : 25, 1 : 50 and 1 : 100). The results showed a moderate agreement of ELISA at both cut-offs (kappa = 0.46 and 0.51) with MAT at a cut-off titre of 1 : 100. However, the specificity and positive predictive value were above 95% only at an ELISA cut-off of 100%, indicating its potential as a diagnostic test, particularly in areas with a high prevalence of infection. On the other hand, lower sensitivity and negative predictive value limit its value as a screening test. Thus, the ELISA Toxotest may be used for quick diagnosis of T. gondii infection in sheep in the field, i.e. for the differential diagnosis of ovine abortion storms.  相似文献   
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