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O objetivo da revisão foi descrever as características físicas e químicas do caulim, a fim de se conhecer a substância e propor como opção de marcador externo de consumo de matéria seca e excreção fecal de bovinos de corte em pastejo. Um marcador é considerado ideal quando apresenta características como ser inerte, não ser tóxico, não ter funçã o fisiológica, não ser metabolizado, entre outras. Atualmente todos os marcadores possuem limitações, com isso pesquisas têm sido realizadas com intuito de descobrir um marcador que apresente todas esses atributos. Assim, o caulim destaca-se como interessante alternativa, pois além de fazer parte da nutriçã o dos animais, trata-se de um mineral cujas características evidenciam possível aplicaçã o, como ser inerte em ampla faixa de pH (3 a 9), fácil dispersão, baixa condutividade térmica e elétrica, baixo custo e boa resistência ao ataque químico por ácidos ou álcalis. Para a mensuração da substância via fezes, é preciso determinar a concentração de algum de seus elementos, ou seja, pelo fato do Al de estar presente nas forrageiras em concentração muito pequena, e metodologia analítica mais prática, leva a acreditar que este elemento é a escolha mais coerente. Conclui-se que o caulim características de um potencial marcador externo e pode ser quantificado com precisão nas fezes por meio do elemento alumínio.

Wetland grasslands are important ecosystems for raising beef cattle, because they are highly productive and present forages with high quality. Most of these ecosystems are threatened by overgrazing or by being replaced by exotic pastures. Emergy synthesis approach was used to assess and value the services provided by native pastures wetland under three conservation status and also to compare them to exotic pastures on wetlands. The ecosystem service that was assessed included forage provision for calves production estimated from grazing capacity of cow with calf at the foot. Habitat maintenance to plant diversity and wild herbivores were also evaluated. The results showed that natural wetland pastures with better conservation status provided valuable ecosystem services and are highly renewable. Data envelopment analysis (DEA) showed that regardless of the conservation state of the natural pastures, wet native grasslands were more efficient than wet exotic grasslands. Replacing native pastures by exotic ones may reduce plant diversity and the renewability of the system. The proposed method has a holistic approach to pasture ecosystems and is able to help decision-makers to define sustainable management practices and to subsidise public policies when it comes to payments regarding ecosystem services.

Early weaning (EW) has been adopted in cattle breeding farms in Pantanal as a strategy to increase the rate of pregnancy in cows. The primary income of these properties is the production of beef calves, and the price of these animals depends on their weight. Therefore, the calves subjected to EW should present weight similar to or higher than those of calves subjected to conventional weaning (CW). This study aimed to evaluate the productive performance of pure (Nellore) calves and crossbred (Nellore/Angus) calves reared in the Pantanal and subjected to either EW or CW. After EW, the calves were supplemented with concentrate at 1 kg/animal/day (low-energy diet) or 1% of live weight (high-energy diet). The weights adjusted to 300 days of age were higher for EW calves fed the high-energy diet (p0.01), and animal weight was 241.17 and 236.27 kg in crossbred calves and 184.44 and 189.78 in Nellore calves, respectively. The EW adopted in this experimental model did not affect the productive performance of calves raised in the Pantanal.

Bovine livestock is a major anthropogenic greenhouse gas source via entericmethane. Brazilian bovine livestock is also responsible for emissions from land-use changes. In contrast, enteric emissions from extensive cattle systems in wetlands might have been overestimated.We provide scientific evidences that the human footprint of bovine products delivered by the Pantanal can be much lower. To assess this, a historical cloud-free imagery of the Landsat-5, spanning 26 years, were processed for mapping spatiotemporal landscapes in a Pantanal farm under cattle intensification studies. Eight landscape categories were identified according to spatiotemporal dynamics of interannual floods. The spatiotemporal map allowed in the field the adoption of stratified randomsamplings of chamber gas fluxes. The combination of stratified sampled landscapes with Monte Carlo simulations of measured methane emissions in wet and dry soils permitted to integrate landscapes emissions at annual basis with biased uncertainties. Assuming enteric emissions obtained for the Pantanal region, our results suggest that the landscapes methane emissions are 10- to 23-fold superior than the enteric emissions of traditional bovine systems. While enteric emissions seem negligible with respect to net farmland emissions, cattle livestock provide important environmental services like carbon recycling through non-competing herbivory. Moreover, cattlemight be making use of a biomass thatwould undergo decomposition during the flooding phase. Our analysis thus indicate that enteric emissions from traditional bovine systems in flooding farmlands could be considered neutral. By contrast, intensification to improve the stocking rate should be accounted as net anthropogenic emissions. A case study of intensification allowed an increase of 48% in the stocking rate,which is associatedwith net anthropogenic emissions from534 bovine animals or about 27 to 63Mg of enteric CH4 per year. In short, the competition between traditional and distinct levels of cattle intensification will result from a trade-off between public policies and strategic market niches (organic, sustainable) for the optimal landscape management of the Pantanal. Made available in DSpace on 2018-12-27T23:38:50Z (GMT). No. of bitstreams: 1 Couldbovinelivestockintensification.pdf: 3043879 bytes, checksum: c72ee9f22cf657e2539cc7582797a1a2 (MD5) Previous issue date: 2018-12-27

The objective of this trial was to evaluate different post-timed artificial insemination (TAI) reproductive managements in postpartum beef cows to produce crossbred calves from artificial insemination (AI). Nellore cows (n = 607), with 45 days postpartum, were inseminated at a fixed time, using a protocol that included an intravaginal progesterone-releasing device along with oestradiol benzoate, prostaglandin, equine chorionic gonadotropin, and oestradiol cypionate, followed TAI 48 h post-device removal. Four post-TAI treatments were evaluated: in CONTROL (T1, n = 161), cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). In OBSERVATION (T2, n = 132), heat detection was performed for 15–25 days post-TAI, followed by AI. In RESYNC22 (T3, n = 157) and RESYNC30 (T4, n = 157), resynchronisation started after 22 or 30 days, following second TAI at Day 32 or 40 days after first TAI. In T2, T3 and T4, after the second AI, cows were exposed to Nellore clean-up bulls until the end of the breeding season (75 days). The pregnancy rate (PR) for the first TAI did not differ (54.6%, 53.0%, 59.2%, and 51.6% for CONTROL, OBSERVATION, RESYNC 22, and RESYNC 30, respectively; P = 0.66), and no difference was observed for the second TAI (RESYNC 22 = 45.31% and RESYNC30 = 46.05%; P = 0.137), in the PR at the end of the breeding season (86.33%, 86.36%, 78.98%, and 81.52%, P = 0.43), or embryonic losses (4.54%, 2.85%, 6.45% and 7.40%, respectively; P = 0.61), but the percentage of crossbred pregnancy was higher in groups with resynchronisation (RESYNC22 and RESYNC30) than CONTROL and OBSERVATION (98.38%, 90.62%, 63.30%, 78.95%, P < 0.001). In conclusion, resynchronisation programs of 22 or 30 days are more efficient to produce AI products, and the final pregnancy rate is similar among the treatments, differing only in the amount of calves produced by AI.

A nutricao animal necessita de metodologias simples que possam ser aplicadas em condicoes de campo, que sejam capazes de fornecer estimativas validas de consumo e digestibilidade e que possam ser utilizadas tanto pelos produtores rurais quanto pela industria produtora de insumos para animais. Assim a busca por novas substâncias, fornecidas de forma pratica, quantificadas por metodologias analiticas simples e de baixo custo em substituicao aos indicadores externos (oxido cromico usado como referencia) seriam bem aceitas pela comunidade cientifica. Neste contexto objetivou-se avaliar o fornecimento do oxido cromico via esofagica ou misturado na racao, e o uso do caulim como indicador, sob as mesmas formas de fornecimento, para estimar a producao fecal e digestibilidade, utilizando quatro bovinos machos castrados da raca Holandesa. Foram testados quatro tratamentos, distribuidos aos animais segundo um delineamento quadrado latino 4x4, sendo o primeiro aquele em que os animais foram submetidos ao fornecimento de oxido cromico fornecido via esofagica (OCesof), no segundo tratamento os animais receberam o caulim via esofagica (Caulesof), no terceiro o fornecimento do oxido cromico aos animais foi misturado a racao (OCrac) e no quarto tratamento o caulim foi administrado misturado a racao (Caulrac), em quatro periodos experimentais de 12 dias, com intervalos de seis dias entre os periodos. O tratamento Caulrac permitiu obter estimativas de producao fecal semelhante ao tratamento OCesof. O tratamento OCrac nao diferiu do tratamento OCesof (p > 0,05) em nenhum dos parâmetros avaliados, evidenciando que o indicador oxido cromico pode ser fornecido misturado diretamente na racao sem prejudicar as estimativas de producao fecal e digestibilidade.

One of the most relevant issues in discussion worldwide nowadays is the concept of sustainability. However, sustainability assessment is a difficult task due to the complexity of factors involved in the natural world added to the human interference. In order to assess the sustainability of beef ranching in complex and uncertain tropical environment systems this paper describes a decision support system based on fuzzy rule-approach, the Sustainable Pantanal Ranch (SPR). This tool was built by a set of measurements and indicators integrated by fuzzy logic to evaluate the attributes of the three dimensions of sustainability. Indicators and decision rules, as well as scenario evaluations, were obtained from workshops involving multi-disciplinary team of experts. A Fuzzy Rule-Based System (FRBS) was developed to each attribute, dimension and general index. The essential parts of the FRBS are the knowledge database, rules and the inference engine. The FuzzyGen and WebFuzzy tools were developed to support the FRBS and both showed efficiency and low cost for digital applications. The results of each attribute, dimension and index were presented as radar graphs, showing the individual value (0–10) of each indicator. In the validation process using the WebFuzzy, different combinations of indicators were made for each attribute index to show the corresponding output, and which confirm the feasibility and usability of the tool.

Objetivou-se avaliar a eficiência de dietas contendo diferentes aditivos sobre o desempenho, características qualitativas da carcaça e da carne de 150 novilhas Brangus suplementadas a pasto diariamente com 0,32% do peso vivo. Os tratamentos foram: suplemento base (sem aditivos); farinha de algas calcárias (Lithothamnium calcareum) adicionada ao suplemento base; vitamina E e selênio orgânico adicionados ao suplemento base; gordura protegida adicionada ao suplemento base; uma aplicação por via subcutânea de vitamina D 7 dias antes do abate + suplemento base; e uma associação de vitamina E, selênio orgânico e gordura protegida adicionados ao suplemento base + uma aplicação por via subcutânea de vitamina D 7 dias antes do abate. Os animais foram suplementados por 109,80 ± 11,71 dias, quando foram abatidos ao alcançarem 337,95 ± 20,56kg de PV. O delineamento experimental foi inteiramente casualizado, com seis tratamentos e 25 repetições. O desempenho, as características de carcaça e da carne não foram afetados pelos aditivos utilizados. A média da área de olho de lombo de 52,00 cm² e a média da espessura de gordura subcutânea de 3,58mm dos animais que receberam a associação de aditivos não diferiram dos valores dos animais do tratamento controle. A adição de vitamina D3 não teve efeito sobre a força de cisalhamento da carne. O uso de aditivos conforme os protocolos adotados não foi eficiente para melhorar o desempenho, as características de carcaça e as características físicas da carne de novilhas suplementadas a pasto. Aimed with this study to evaluate the efficiency of diets with different additives on the performance, carcass and meat traits of 150 Brangus heifers supplemented on pasture daily with 0,32% of live weight. The treatments were: supplement (no additives); seaweed flour (Lithothamnium calcareum) added to the supplement; vitamin E and organic selenium added to the supplement; protected fat added to the supplement; an application subcutaneously of vitamin D seven days before slaughter + supplement; and the association of vitamin E, organic selenium and protected fat added to the supplement + one dose of vitamin D seven days before slaughter. The animals were supplemented by 109,80 ± 11,71 days, when they were slaughtered when reached 337,95 ± 20,56kg. The experimental design was completely randomized with six treatments and 25 repetitions. The performance, the carcass and meat characteristics were not affected by the additives used. The average ribeye area of 52,00cm² and the average fat thickness of 3,58 mm in the animals receiving the combination of additives did not differ from the values of the control treatment. The addition of vitamin D3 had no effect on shear force of Longissimus dorsi samples. The use of additives according to the protocols used did not improve the performance, the carcass and meat characteristics of cattle supplemented on pasture.

This study evaluated the use of cooled semen in a fixed-time artificial insemination (FTAI) program compared with frozen–thawed semen to improve pregnancy rates in beef cattle. Ejaculates of three bulls were collected and divided into two treatments: (1) frozen–thawed semen and (2) cooled semen. Egg-yolk extender without glycerol was used for the cooled semen treatment. Straws (25 × 106 spermatozoa) were submitted to cooling for preservation at 5°C for 24 h, after which FTAI was performed. Nelore cows (n = 838) submitted to FTAI were randomly inseminated using frozen–thawed semen or cooled semen. There was a 20% increase in the pregnancy per AI (P AI–1) using cooled semen compared with frozen–thawed semen (59.9 ± 4.7 vs 49.4 ± 5.0%; P 0.05). Because there was less damage to spermatozoa and improvement in P AI–1, the use of cooled semen instead of frozen–thawed semen is an interesting approach to increase reproductive efficiency in cattle submitted to a FTAI protocol.

Use of eCG as an inducer of follicular growth has improved the efficacy of fixed-time artificial insemination (FTAI) protocols and increased the ovulatory responses and pregnancy rates in beef cattle with low body condition scores (BCS) or are recently postpartum and anestrous. However, there are other gonadotropins such as FSH in different commercial applications (Pluset® – FSH : LH proportion ~50.0%) that could be potentially used to increase follicular growth but with controversial results. The goal of this trial was to evaluate the effects of replacing eCG with FSH/LH in two moments on the pregnancy rates (PR) of lactating Bos indicus cows raised in native grassland at Pantanal. The cows were subjected to a synchronization-of-ovulation protocol and FTAI based on progesterone, oestradiol benzoate (EB), and prostaglandin F2α. On Day 0, Nellore multiparous cows (n = 352) at 42 days postpartum with BCS = 4.9 (1–9) were evaluated by transrectal ultrasonography and received progesterone implant (DIB 1.0 g of progesterone) plus 2 mg of EB IM. Devices were removed and prostaglandin F2α was injected on Day 8 with 1 mg of EB. At the time of implant removal, the animals received T1 – 1 mL of saline solution IM (control; n = 80); T2 – 300 IU IM of eCG (Novormon®; ECG; n = 92); T3 – 40 IU IM of FSH/LH (Pluset®; Pluset; n = 98). The T4-group cows received 40 IU IM of FSH/LH (Pluset®) at FTAI time (Pluset-FTAI; n = 82); cows were timed-AI on Day 10 (44–48 h after implant removal) and evaluated by transrectal ultrasonography to measure the preovulatory follicle (POF) at FTAI and to estimate the pregnancy rate on Day 45. The effects of the treatment, sire, and BCS on pregnancy rate were evaluated using PROC GLIMMIX (SAS Institute Inc., Cary, NC). Because there was no difference between BCS, sire, and PR, they were removed from model. Pregnancy rate was not different between the treatment groups (control: 38.70%; ECG: 51.08%; Pluset: 45.91%, and Pluset-FTAI: 39.02%; P > 0.05), but the difference was found in POF, higher in ECG group – 13.53 mm compared with others (Pluset: 12.79 mm; control: 11.73 mm, and Pluset-FTAI: 12.01 mm; P