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1.
Plants (Basel) ; 13(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38732389

RESUMO

This study explores the impact of a novel phytogenic product containing citric acid, carvacrol, and cinnamaldehyde on buffel grass (Cenchrus ciliaris) seedling emergence. A dilution series of the phytogenic solution revealed a concentration range that promoted seedling emergence, with an optimal concentration of 0.5%. Transcriptomic analysis using RNA-seq was performed to investigate gene expression changes in seedlings under the influence of the phytogenic product. The results revealed that the phytogenic treatment significantly altered the gene expression, with a prevalent boost in transcriptional activity compared to the control. Functional analysis indicated the positive alteration of key metabolic pathways, including the tricarboxylic acid (TCA) cycle, glycolysis, and pentose phosphate pathways. Moreover, pathways related to amino acids, nucleotide biosynthesis, heme biosynthesis, and formyltetrahydrofolate biosynthesis showed substantial modulation. The study provides valuable insights into the molecular mechanisms underlying the phytogenic product's effects on grass seedling establishment and highlights its ability to promote energy metabolism and essential biosynthetic pathways for plant growth.

2.
Trop Anim Health Prod ; 56(3): 120, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607525

RESUMO

The current study evaluated the effects of supplementing cassava root silage (CRS) to dairy cows grazing on Megathyrsus maximus cv Mombasa on nutrient intake and digestibility, as well as on milk production and composition. Ten primiparous Girolando cows with average body weight ± (SEM) of 373.45 ± (63.55) kg were used in a replicated 5 × 5 Latin square. Animals were subjected to five treatments: (I) grazing cows without supplementation (WCS); (II) grazing cows provided with 5 kg DM of supplement without CRS (0 g/kg DM of CRS) or including (III) 260, (IV) 520, and (V) 780 g/kg DM of CRS. Statistical analyses were performed using the PROC MIXED of SAS with significance at P < 0.05. Intake of neutral detergent fiber (NDF) and ether extract decreased (P < 0.01), while intake of non-fiber carbohydrates increased (P < 0.01), with increased CRS in the diets. Total DM intake and digestibility of DM, and digestibility of nutritional components were lower (P < 0.03) in WCS animals compared to supplemented animals, except for intake and digestibility of NDF, which was the opposite. Milk yield (MY) and fat corrected milk (FCM), as well as all milk components were unaffected (P > 0.05) by CRS inclusion. In contrast, MY, FCM, protein, lactose, casein, and non-fat milk solids (NFMS) were greater for animals that received supplementation (P < 0.05), compared to animals WCS. Milk fat and total dry extract (TMS) did not differ (P > 0.11) between two groups. In conclusion, CRS may be a potential corn meal replacer in the supplement of dairy cows under tropical conditions.


Assuntos
Manihot , Feminino , Bovinos , Animais , Leite , Silagem , Quênia , Nutrientes , Extratos Vegetais
3.
Anim Welf ; 33: e18, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618293

RESUMO

The complexity experienced in early life can affect trait development of individuals, including sociability and fearfulness. The modern dairy calf's rearing environment often lacks environmental and social complexity. This study examined the effects of early-life, non-maternal adult contact and access to a physically complex environment on the responses of dairy heifers to several stressors, including restraint, social isolation, and novelty at 18 months of age. From the age of 2-13 weeks, 60 dairy heifers (Bos taurus) were reared according to one of three treatments applied to 20 calves each: (1) Hand-reared at pasture in groups of ten, with three unrelated dry cows (+S); (2) Hand-reared at pasture in groups of ten (-S); or (3) Hand-reared in sheds in groups of 10-12 as a commercial control (CC). At 13 weeks, all treatment groups were mixed and managed at pasture as a single herd. At 18 months, the responses of 50 heifers to restraint in a crush, social isolation and a novel object were observed (+S = 16, -S = 17, CC = 17). Treatment did not influence responses to restraint or social isolation, but influenced some indicators of fearfulness during exposure to a novel object. Six +S heifers interacted with the novel object compared to 0 -S and one CC, and CC heifers spent around 50% more time in vigilance than +S or -S heifers. Dairy heifers provided with early-life social enrichment in the form of non-maternal adult contact may have reduced fear of novelty. The implications for lifelong ability to adapt to novel situations, such as entry into the milking herd, should be assessed.

4.
Trop Anim Health Prod ; 56(4): 140, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656670

RESUMO

This study evaluated three continuous grazing systems: Brachiaria Brizantha, Clitoria ternatea and naturalized pastures, complemented with commercial concentrate and C. ternatea silage on milk yield, nutrient use and enteric methane (CH4) emissions. Nine multiparous cows of local Zebu breeds, with an average weight of 448 ± 87 kg, were used. The chemical composition of the food was determined. Live weight, milk production, and quality were assessed. Furthermore, serum urea, urea nitrogen, creatinine and glucose in blood were monitored, and nitrogen use efficiency were calculated. Enteric methane (CH4) emissions were estimated using Tier-2 methodology. A 3 × 3 latin square experimental design was applied. The grazing systems of B. brizantha and C. ternatea had the greater live weights of 465.8 and 453.3 kg/cow, although the latter is similar to naturalized pasture. Milk production and quality were not affected by grazing system, with the exception of the non-fat solids, where the C. ternatea system was lower (102.2 g/kg) than the other grazing systems. The crude protein and N intake, and N excretion in feces and urine were lower in naturalized pasture systems (1139.0 g/day). N outputs in milk was high in the C. ternatea system (56.3 g/cow/day). The naturalized pastures systems showed the better feed use efficiency (25.7%) compared to others. Serum urea and blood urea nitrogen were greater in B. brizantha followed by C. ternatea. Enteric CH4 emissions were indifferent among grazing systems when expressed as a percentage of greenhouse gases (7.1%). In conclusion, the grazing C. ternatea supplemented with commercial concentrate and C. ternatea silage maintains milk production and quality, reduced cow/day emissions (by 2.5%) and lowered energy losses as methane.


Assuntos
Ração Animal , Lactação , Metano , Leite , Animais , Bovinos/fisiologia , Metano/análise , Metano/metabolismo , Feminino , Lactação/fisiologia , Leite/química , Leite/metabolismo , Ração Animal/análise , Dieta/veterinária , Criação de Animais Domésticos/métodos , Silagem/análise , Fenômenos Fisiológicos da Nutrição Animal , Brachiaria , Nitrogênio/metabolismo , Nitrogênio/análise , Nutrientes/análise , Nutrientes/metabolismo , Fabaceae/química
5.
Sensors (Basel) ; 24(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38610536

RESUMO

Rising platemeters are commonly used in Ireland and New Zealand for managing intensive pastures. To assess the applicability of a commercial rising platemeter operating with a microsonic sensor to estimate herbage mass with its own equation, the objectives were (i) to validate the original equation; (ii) to identify possible factors hampering its accuracy and precision; and (iii) to develop a new equation for heterogeneous swards. A comprehensive dataset (n = 1511) was compiled on the pastures of dairy farms. Compressed sward heights were measured by the rising platemeter. Herbage mass was harvested to determine reference herbage availability. The adequacy of estimating herbage mass was assessed using root mean squared error (RMSE) and mean bias. As the adequacy of the original equation was low, a new equation was developed using multiple regression models. The mean bias and the RMSE for the new equation were overall low with 201 kg dry matter/ha and 34.6%, but it tended to overestimate herbage availability at herbage mass < 500 kg dry matter/ha and underestimate it at >2500 kg dry matter/ha. Still, the newly developed equation for the microsonic sensor-based rising platemeter allows for accurate and precise estimation of available herbage mass on pastures.


Assuntos
Calibragem , Fazendas , Irlanda
6.
Trop Anim Health Prod ; 56(3): 111, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520485

RESUMO

This study evaluated levels of replacement of soybean meal by castor bean meal in the finishing crossbred steers on Brachiaria brizantha cv. Marandu pasture during the rainy-dry transition period. Forty Holstein-Zebu crossbred steers with an average initial weight of 395.93 ± 10 kg were randomly allocated to four treatment groups that were supplemented with concentrate levels of replacing (0, 290, 613, and 903 g/kg DM of the supplement; at 0.4% body weight [BW]). The experimental period was 120 days. A completely randomized experimental design was adopted; with regression analysis using the computational software package (SAS 9.2, USA). Intake and digestibility of dry matter (DM) and nutrients and animal performance were evaluated. The replacement levels did not influence (P > 0.05) the intakes of DM (kg/day), organic matter (OM, kg/day), neutral detergent fiber (NDF, kg/day and %BW), non-fibrous carbohydrates (NFC, kg/day), or total digestible nutrients (kg/day). However, the intake of crude protein (CP) and ether extract (EE, kg/day) decreased as the replacement levels were increased (P < 0.05). The digestibility of DM, OM, NDF, and EE did not change, whereas CP digestibility decreased linearly and NFC digestibility increased linearly (P < 0.05). The replacement levels did not affect (P > 0.05) final body weight, average daily gain, feed conversion, and carcass yield. Castor bean meal can replace up to 903 g/kg DM of soybean meal in the composition of the supplement without compromising the performance of steers on Marandu pasture during the rainy-dry transition period.


Assuntos
Ricinus communis , Animais , Digestão , Suplementos Nutricionais/análise , Carboidratos , Proteínas , Peso Corporal , Ração Animal/análise , Dieta/veterinária
7.
Animal ; 18(4): 101117, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520773

RESUMO

Environmental conditions and available forage on pastures greatly differ between different farming systems, which can affect the behaviour of grazing cattle. The interplay between environment-, forage-, and animal-related variables may affect the use of feed and water resources in grazing-based systems. Hence, our objectives were (i) to study the differences between grazing-based systems and seasons in environment- and pasture-related variables as well as the behaviour, feed intake, performance, and water productivity of Nellore heifers, and (ii) to understand the interrelationships between these variables. The measurements were performed in a conventional grazing system (CON), an integrated crop-livestock (ICL), and a crop-livestock-forestry (ICLF) systems in the Brazilian Cerrado during the rainy and dry seasons. Ambient temperature and relative air humidity were hourly measured in both seasons. Forage biomass and sward height were determined every month. Forage samples were taken to determine the proportions of alive leaves, alive stems, and dead plant material and to analyse their nutritive value. Forage intake, drinking water intake, and liveweight changes were quantified in 12 Nellore heifers per system and season. Feeding behaviour was recorded by chewing sensors on nine continuous days in each season. Drinking water intake was measured by water meters attached to drinking water troughs, whereby trial cameras at the troughs recorded the frequency of drinking events of individual animals. Feed conversion efficiency and water productivity were estimated. The ICLF reduced the exposure time to high ambient temperatures so that heifers even grazed during the hottest hours. Forage biomass in ICL and CON had greater proportions of stem and dead plant material than in ICLF. Forage intake rate was greater and grazing events were longer for animals in ICLF than those in CON, whereas the daily number of grazing events was greater in CON. Feed conversion efficiency and water productivity were greater in integrated systems than in CON. Amongst studied variables, thermal environment and forage canopy structure with its proportions of dead plant material are the main driving factors for animal behaviour, forage intake rate, and animal performance. These variables reduce feed conversion efficiency and water productivity in grazing cattle. Further research should analyse strategies for promoting thermal comfort for the animals, increasing the proportions of alive biomass, and enhancing the nutritional value of pastures for more efficient use of forage and water resources in grazing-based systems.


Assuntos
Dieta , Água Potável , Bovinos , Animais , Feminino , Dieta/veterinária , Gado , Água Potável/análise , Ingestão de Alimentos , Comportamento Alimentar , Estações do Ano , Ração Animal/análise , Poaceae
8.
Chem Biodivers ; 21(5): e202301880, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38494456

RESUMO

This paper reports on some physicochemical and phytochemical characteristics (i. e. pH, electrical conductivity, colour, moisture content, total phenolic content, sugar profile) and in vitro antioxidant activity of honeys harvested from five legume species, red clover (Trifolium pratense), balansa clover (T. michelianum), Persian clover (T. resupinatum), purple clover (T. purpureum) and sanfoin, also known as holy clover (Onobrychis viciifolia), that were grown in enclosed shade houses to ensure that the honeys' characteristics are reflective of a truly monofloral honey. Glucose and fructose, determined via High-Performance Thin-Layer Chromatography (HPTLC) analysis, were found as the main sugars in all investigated honeys with the ratio of fructose to glucose ranging from 1 : 1.2 to 1 : 1.6. The honeys' pH values ranged from 3.9 to 4.6 which met Codes Alimentarius (CA) requirements. The moisture content was found to be between 17.6 and 22.2 % which in some cases was slightly higher than CA requirements (≤20 %). The honeys' colour values, prior and after filtration, were between 825.5-1149.5 mAU and 532.4-824.8 mAU respectively, illustrating golden yellow to deep yellow hues. The total phenolic content (TPC) of the honeys was determined using a modified Folin-Ciocalteu assay. Their antioxidant activity was captured by the Ferric Reducing-Antioxidant Power (FRAP) assay as well as HPTLC analysis coupled with 2,2-diphenyl-1-picrylhydrazyl (DPPH) derivatisation. The highest total phenolic content was found in red clover honey (45.4 mg GAE/100 g) whereas purple clover honey showed the highest level of activity in the FRAP assay (7.3 mmol Fe2+/kg). HPTLC-DPPH analysis of the honeys' organic extracts demonstrated the presence of various bioactive compounds that contribute to their overall antioxidant activity. This study developed a methodology for producing monofloral clover honeys in a space limited, enclosed production system, which allowed to collate important baseline data for these honeys that can serve as the foundation for their potential future development into commercial honeys, including honeys that can be used for medicinal purposes.


Assuntos
Antioxidantes , Mel , Compostos Fitoquímicos , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/análise , Mel/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Fenóis/análise , Fenóis/química , Concentração de Íons de Hidrogênio , Trifolium/química , Picratos/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Cromatografia em Camada Fina
9.
Animals (Basel) ; 14(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38539977

RESUMO

The objective was to characterize the pastures by grazing cycle, as well as to evaluate the performance of buffaloes in intensive rotational grazing in a silvopastoral system in the eastern Amazon supplemented with agro-industry co-products in order to characterize the grazing cycles, the composition of the fractions, and the carcass yield. Fifteen non-castrated, crossbred water buffaloes (Murrah × Mediterranean) were used. All animals used in the study were clinically healthy and weighed approximately 458 kg. The animals were grazed in a single group, and supplementation (1% of live weight-LW/day) was divided into three treatments: control (control-conventional ingredients); Cocos nucifera coconut cake (Cocos nucifera) (coconut cake-70%); and palm kernel cake (Guinean elaeis) (palm kernel cake-70% palm kernel cake). The chemical composition of the forage is different in each part of the plant, with higher protein values in the leaves (11.40%) and higher acid detergent fiber (ADF) values in the stems (50.03%). Among the ingredients of the supplement, corn has the highest percentage of indigestible protein (35.57%), most of the protein in palm kernel cake is B3 (49.11%), and in Coco, B2 (51.52%). Mombasa grass has a higher percentage of B3 and B2 proteins; the indigestible fraction is lower in the leaves (17.16%). The leaf/stem ratio also varied between grazing cycles, being better in the second cycle (2.11%) and with an overall average of 1.71. Supplement consumption varied between cycles and was higher in the control treatment, with an overall mean of 4.74. There was no difference in daily weight gain and carcass yield, with an average of 1 kg/day and 49.23%, respectively. Therefore, it can be concluded that including supplements based on by-products from the coconut and palm oil agro-industries promotes performance and carcass yields compatible with conventional supplements. Their use reduces production costs, optimizes the utilization of forage mass, enhances the sustainability of the production chain, and, therefore, is recommended.

10.
J Environ Manage ; 356: 120564, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479283

RESUMO

Robust quantification of vegetative biomass using satellite imagery using one or more forms of machine learning (ML) has hitherto been hindered by the extent and quality of training data. Here, we showcase how ML predictive demonstrably improves when additional training data is used. We collated field datasets of pasture biomass obtained via destructive sampling, 'C-Dax' reflective measurements and rising plate meters (RPM) from ten livestock farms across four States in Australia. Remotely sensed data from the Sentinel-2 constellation was used to retrieve aboveground biomass using a novel machine learning paradigm hereafter termed "SPECTRA-FOR" (Spectral Pasture Estimation using Combined Techniques of Random-forest Algorithm for Features Optimisation and Retrieval). Using this framework, we show that the low temporal resolution of Sentinel-2 in high latitude regions with persistent cloud cover leads to extensive gaps between cloud-free images, hindering model performance and, thus, contemporaneous ability to forecast real-time pasture biomass. By leveraging the spectral consistency between Sentinel-2 and Planet Lab SuperDove to overcome this limitation, we used ten spectral bands of Sentinel-2, four bands of Sentinel-2 as a proxy for pre-2022 SuperDove (referred to as synthetic SuperDove or SSD), and the actual SuperDove (ASD), given that SuperDove imagery has a higher resolution and more frequent passage compared with Sentinel-2. Using their respective bands as input features to SPECRA-FOR, model performance for the ten bands of Sentinel-2 were R2 = 0.87, root mean squared error (RMSE) of 439 kg DM/ha and mean absolute error (MAE) of 255 kg DM/ha, while that for SSD increased to an R2 of 0.92, RMSE of 346 kg DM/ha and MAE = 208 kg DM/ha. The study revealed the importance of robust data mining, imagery harmonisation and model validation for accurate real-time modelling of pasture biomass with ML.


Assuntos
Aprendizado de Máquina , Imagens de Satélites , Imagens de Satélites/métodos , Biomassa , Fazendas , Austrália
11.
J Therm Biol ; 121: 103833, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38527387

RESUMO

Dairy cows in pasture-based systems are more susceptible to heat stress. Holstein cows have the black or red phenotypes, the latter having lower absorbance of solar radiation. Therefore, the study's objective was to evaluate whether cows with red (R) coats are more resistant than black (B) cows to hot weather in a subtropical climate. R and B lactating Holstein cows were evaluated during the cold and hot seasons for internal and surface temperature and sweating rate. In the cold season, body temperature (n = 9/group) did not differ between groups, but the average superficial temperature (n = 13/group) was lower in R cows (B: 30.9 ± 0.3 °C; RW: 29.6 ± 0.3 °C; p = 0.02). In the hot season, under mild to moderate heat stress, mean body temperature (n = 9/group) of R cows was lower (B: 38.75 ± 0.01 °C; R: 38.62 ± 0.1 °C; p=<0.0001), whereas no difference was observed in superficial temperature (n = 17/group). The maximum internal temperature and sweating rate (n = 11/group), measured in the hot season, and the number of evaluations in hyperthermia in both seasons did not differ. Therefore, there were differences in thermoregulation between phenotypes under mild to moderate heat stress conditions. However, considering that only discrete differences were observed, the red and white coat is unlikely to benefit the Holstein cow's welfare under mild to moderate thermal stress.

12.
Vet Med Sci ; 10(3): e1415, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38504663

RESUMO

BACKGROUND: Feed is a major input in the livestock industry and covers about 60%-70% of the total cost of producing meat, milk and eggs. Inadequate feed supply in terms of quality and quantity leads to lower production performance in livestock. However, the development of an appropriate livestock production strategy through efficient utilization of existing feed resources could raise the production and per capita consumption of livestock products. Efficiency of feed resource utilization can be measured as the ratio between input to production activities and output (e.g. kg of protein used per unit of meat, milk and eggs produced or hectare of land used per unit of milk produced). METHODOLOGY: This study was designed with the objective of evaluating the livestock population and national feed security to enhance livestock productivity in Ethiopia. To achieve this objective, data were collected from the websites of the Ethiopian Central Statistical Agency from 2007 to 2021, FAO publications and websites, books and journals. The data obtained on different feed resources, livestock population and livestock feed requirement and balance were entered into an MS Excel spread sheet (Excel, 2010) and analysed using the general linear model (PRO GLM) procedure of SAS (2014) and multivariate analysis of covariance. RESULTS: The study results revealed that the livestock population had increased from 58.31 million tropical livestock units (TLU) to 81.10 million tropical livestock units (TLU), and the emission of entericCH4 had increased from 2511.08 Gg/year to 3661.74 Gg/year from 2008 to 2021. The study results also showed that the major available feed resources for ruminants are natural pasture and crop residues, which account for 56.83% (87.56 × 106 ) and 37.37% (57.57 × 106 ) of total feed production in the country, respectively. The contribution of concentrate and improved cultivated pasture and feed from permanent crops used as feed sources is very insignificant (3.05% and 1.96%, respectively). The estimated quantity of these feed resources was sufficient to meet the livestock feed requirement in the country in terms of dry matter (DM), digestible crude protein (DCP) and MEJ, which estimated about 153.31 × 106  t, 4.56 × 106  t and 1203.97 × 109  MJ DM, DCP and MEJ, respectively. The estimated livestock feed requirements were 134.62 × 106 , 4.52 × 106 , and 918.83 × 109 in DM, DCP and MEJ, respectively. The supply covered about 114.33, 100.04 and 131.33% of the DM, DCP and MEJ total annual feed requirements of livestock in the country. Hence, the current feed surplus obtained on feed requirements of ruminants and equines can support the nutrient requirements of 500 × 106 broilers, about 5 × 106 bulls, about 50 × 106 small ruminants or 3 × 106 crossbred lactating dairy cows, yielding 10 L of milk per day. CONCLUSIONS: The findings of study indicated that natural pasture and crop residues cover a major proportion of the annual feed supply in the country. Therefore, proper grazing management, feed conservation practices, improving grazing land vegetation through clearing invasive species, replacing the grazing land with an improved grass and legume mixture, effective collection, conservation and proper utilization of crop residues, and other alternative options such as the use of chemical, physical and biological treatments to improve the nutritive value of fibrous feed should be practiced. More effective extension services and farmer training are also required to increase feed productivity and, hence, human development.


Assuntos
Dieta , Lactação , Humanos , Feminino , Masculino , Bovinos , Animais , Cavalos , Dieta/veterinária , Gado , Ração Animal/análise , Etiópia , Galinhas , Estações do Ano , Indústria de Laticínios/métodos , Ruminantes
13.
Ying Yong Sheng Tai Xue Bao ; 35(1): 17-24, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511435

RESUMO

We established the systematic concept framework of shelterbelt construction, with "shelterbelts" as the core concern in the construction of integrated ecosystems including mountain, river, forest, farmland, lake, grassland and sandy-land in semi-arid wind-sand areas. In the construction of shelterbelts, it is necessary to adhere to the principles of scientific coordination and systematic management, considering the carrying capacity of water resources, the demand for dust control, the greening and beautification effects, as well as the principle of improving economic benefits. In practice, the construction methods should base on the types and temporal-spatial distribution of shelterbelts, following the shelterbelts construction theory and technology to form different structure and service functions, achieving the functional goals of shelterbelts. By focusing on the key elements including people, forests, grass, fields, water, and sand, we put forward the timeliness, practicality, and scientificity of shelterbelt construction, proposing construction methods for farmland shelterbelts, pastureland shelterbelts, windbreak and sand-fixing forests and protective forest around village (city), which might provide production technical support for the high-quality construction of green ecological barrier in northern China.


Assuntos
Ecossistema , Vento , Humanos , Fazendas , Pradaria , Rios , Lagos , Florestas , Conservação dos Recursos Naturais , China
14.
Plants (Basel) ; 13(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38498419

RESUMO

Effects of rising atmospheric CO2 concentration [CO2] on pastures and grazing lands are beginning to be researched, but these important systems remain understudied compared to other agronomic and forest ecosystems. Therefore, we conducted a long-term (2005-2015) study of bahiagrass (Paspalum notatum Flüggé) response to elevated [CO2] and fertility management. The study was conducted at the USDA-ARS, National Soil Dynamics Laboratory open-top field chamber facility, Auburn, AL. A newly established bahiagrass pasture was exposed to either ambient or elevated (ambient + 200 µmol mol-1) [CO2]. Following one year of pasture establishment, half the plots received a fertilizer treatment [N at 90 kg ha-1 three times yearly plus P, K, and lime as recommended by soil testing]; the remaining plots received no fertilization. These treatments were implemented to represent managed (M) and unmanaged (U) pastures; both are common in the southeastern US. Root cores (0-60 cm depth) were collected annually in October and processed using standard procedures. Fertility additions consistently increased both root length density (53.8%) and root dry weight density (68.2%) compared to unmanaged plots, but these root variables were generally unaffected by either [CO2] or its interaction with management. The results suggest that southern bahiagrass pastures could benefit greatly from fertilizer additions. However, bahiagrass pasture root growth is unlikely to be greatly affected by rising atmospheric [CO2], at least by those levels expected during this century.

15.
Front Microbiol ; 15: 1132151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468851

RESUMO

Introduction: The variation in bacterial communities among breeds has been previously reported and may be one of the reasons why Holstein × Gyr dairy heifers have better development in grazing systems in tropical conditions. This study aimed to explore the ruminal microbiota composition, the IL-1ß gene variation, tick incidence, and blood parameters of Holstein × Gyr (½ Holstein × ½ Gyr) and Holstein heifers grazing intensely managed Guinea grass (Panicum maximum Jacq. cv. Mombaça). Methods: Sixteen heifers were divided into two groups consisting of 8 Holstein × Gyr and 8 Holstein heifers. The experimental period was comprised of 3 periods of 21 days. Ruminal samples were taken via the stomach tube technique. The sequencing of the V4 hypervariable region of the 16S rRNA gene was performed using the Illumina MiSeq platform. Counting and collection of ticks were conducted each 21 days. Blood and skeletal muscle tissue biopsies were performed at the end of the experiment. Results: Firmicutes were the most abundant phyla present in both breed rumen samples and Bacteroidota showed differences in relative abundance between breed groups, with greater values for Holstein heifers (p < 0.05 with FDR correction). The 10 most abundant unique OTUs identified in each breed included several OTUs of the genus Prevotella. Holstein heifers had a greater tick count and weight (9.8 ticks/animal and 1.6 g/animal, respectively) than Holstein × Gyr (2.56 ticks/animal and 0.4 g/animal, respectively). We found nucleotide substitutions in the IL-1ß gene that might be related to adaptation and resistance phenotypes to tick infestation in Holstein × Gyr heifers. Blood concentrations of urea, albumin, insulin-like growth factor 1, triiodothyronine, and thyroxine were greater in Holstein × Gyr than in Holstein heifers. Conclusion: Adaptations in Holstein × Gyr heifers such as ruminal microbiota, tick resistance, nucleotide substitutions in IL-1ß gene, and hormone concentration suggest a better energy metabolism and thermoregulation resulting in better performance in tropical grazing systems.

16.
Animals (Basel) ; 14(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38473131

RESUMO

Studies have been carried out on the effect of large-volume blood harvesting from horses, but they were performed on nonpregnant horses of various breeds other than Icelandic horses. This study aimed to investigate the effect on the haematological variables indicating erythropoiesis of repeated blood harvesting from pregnant mares. To account for regional variation, two herds of mares were chosen, both kept under free-range conditions. Sequential EDTA blood samples were collected weekly from 160 mares and analysed for haematological variables in an automated analyser. Serum samples from 115 mares were analysed for total protein. In both herds, after three harvests, mares began to measure below the minimum value for erythrocyte numbers, and mild anaemia was present in up to 37% at one time. Mares in only one herd had moderate or marked anaemia, 14.3% of the herd. Both herds showed evidence of increased erythropoiesis, but there was a difference between the herds in the intensity of the response. In both herds, however, all mares had reached the minimum normal haematocrit value three weeks after the last harvest. It is important to investigate the causes for the differences between these herds, which might be addressed to reduce the risk of anaemia.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38367244

RESUMO

This study's objective was to compare two options of pasture supplementation: corn silage (CS) alone or corn silage mixed with protein concentrate. The experiment was conducted with 18 lactating Holstein cows in mid-lactation in a crossover design that included three treatments and three data collection periods. All cows had access to pasture for 17 h/day with an average herbage allowance of 16 kg dry matter (DM)/cow/day and were offered in-barn corn silage, corn silage mixed with protein concentrate, or no supplementation. Cows were equipped with pH sensors residing in the reticulum and, during the 7-day data collection periods, with a jaw movement recorder. Nonsupplemented cows produced 21.3 kg energy-corrected milk (ECM) and ate 13.3 kg DM herbage at pasture. Cows supplemented with corn silage and corn silage plus protein produced 2.5 and 4.5 kg/day more ECM, respectively, consumed 3.4 and 3.3 kg/day more DM in total, respectively, ate for a shorter period of time, and ruminated longer than their nonsupplemented peers. Supplemented cows were almost able to cover their energy requirements and mobilised less body mass in contrast to the nonsupplemented cows. Cows offered corn silage plus protein showed increased ECM production, increased milk urea content and lower nitrogen use efficiency (NUE) compared to cows supplemented with corn silage only. Nonsupplemented dairy cows had the highest milk urea content and performed worst in terms of NUE. The best feed conversion efficiency resulted from the nonsupplemented dairy cows and those supplemented with corn silage plus protein. In nonsupplemented cows, the high feed conversion efficiency seemed to be due to the increased mobilisation of body mass. As a result of the starch-rich supplementations, the ruminal acetic:propionic acid ratio became smaller, and the proportions of n-butyric acid increased. The mean reticular pH values did not substantially vary across the three feeding treatments. For the choice of a supplementation option, herbage allowance and cost of supplement will have to be considered, but aspects of feed-food competition as well as animal welfare should not be ignored.

18.
Sci Total Environ ; 918: 170798, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38336055

RESUMO

The production of beef carries significant environmental repercussions on a worldwide level. Considering that the production of beef in Alpine mountainous regions, such as South Tyrol (Italy), constitutes a modest yet progressively growing segment within the local agricultural sector focus must be put on minimizing the environmental impact of producing one kilogram of meat, while also accounting for the carbon sequestered by Alpine pastures in such marginal areas. To this end 20 beef farms distributed in the South Tyrolean region (Italy) were divided based on the age at slaughter of the beef cattle: 10 farms with a slaughter age of 12 months (SA12) and 10 farms with a slaughter age of 24 months (SA24). Live cycle assessment (LCA) approach was used, and the impact was estimated using two functional units (FU): 1 kg of live weight (LW) and 1 kg of carcass weight (CW). Global warming potential (GWP100, kg CO2-eq), acidification potential (AP, g SO2-eq), and eutrophication potential (EP, g PO4-eq) were investigated. Furthermore, within the account, the carbon sequestered by pastures and permanent grassland has been included for estimated the overall carbon footprint. In terms of GWP100, the SA12 system proved to be significantly lower for both two functional units under studies, with reductions of 8.5 % and 7.4 % in terms of LW and CW, respectively, compared to the SA24 system, specifically, the SA12 system showed an environmental impact in terms of GWP100 of 19.5 ± 1.1 kg CO2-eq/kg LW, which was significantly lower than the SA24 system that exhibited a value of 22.9 ± 1.1 kg CO2-eq/kg LW (P < 0.05). When accounting for the carbon sequestered within the system, the observed values in terms of GWP100 are significantly lower for SA12 compared to SA24, 17.6 ± 1.5 vs. 20.9 ± 1.5 kg CO2-eq/Kg LW (P < 0.05), and 29.2 ± 2.5 vs. 38.7 ± 2.5 kg CO2-eq/Kg CW (P < 0.01). These differences are due to less purchase of concentrated feed and greater use of natural resources such as pastures and permanent grasslands. The research indicated that the production of beef in the Alpine region of South Tyrol predominantly occurs within extensive parameters, leading to a satisfactory environmental profile, also including the C sequestration.


Assuntos
Efeito Estufa , Solo , Animais , Bovinos , Sequestro de Carbono , Dióxido de Carbono , Pegada de Carbono , Itália , Carbono
19.
Appl Environ Microbiol ; 90(3): e0175023, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38349147

RESUMO

Phyllosphere microbial communities are increasingly experiencing intense pulse disturbance events such as drought. It is currently unknown how phyllosphere communities respond to such disturbances and if they are able to recover. We explored the stability of phyllosphere communities over time, in response to drought stress, and under recovery from drought on temperate forage grasses. Compositional or functional changes were observed during the disturbance period and whether communities returned to non-stressed levels following recovery. Here, we found that phyllosphere community composition shifts as a result of simulated drought but does not fully recover after irrigation is resumed and that the degree of community response to drought is host species dependent. However, while community composition had changed, we found a high level of functional stability (resistance) over time and in the water deficit treatment. Ecological modeling enabled us to understand community assembly processes over a growing season and to determine if they were disrupted during a disturbance event. Phyllosphere community succession was characterized by a strong level of ecological drift, but drought disturbance resulted in variable selection, or, in other words, communities were diverging due to differences in selective pressures. This successional divergence of communities with drought was unique for each host species. Understanding phyllosphere responses to environmental stresses is important as climate change-induced stresses are expected to reduce crop productivity and phyllosphere functioning. IMPORTANCE: Leaf surface microbiomes have the potential to influence agricultural and ecosystem productivity. We assessed their stability by determining composition, functional resistance, and resilience. Resistance is the degree to which communities remain unchanged as a result of disturbance, and resilience is the ability of a community to recover to pre-disturbance conditions. By understanding the mechanisms of community assembly and how they relate to the resistance and resilience of microbial communities under common environmental stresses such as drought, we can better understand how communities will adapt to a changing environment and how we can promote healthy agricultural microbiomes. In this study, phyllosphere compositional stability was highly related to plant host species phylogeny and, to a lesser extent, known stress tolerances. Phyllosphere community assembly and stability are a result of complex interactions of ecological processes that are differentially imposed by host species.


Assuntos
Bactérias , Microbiota , Bactérias/genética , Plantas , Folhas de Planta/microbiologia , Especificidade de Hospedeiro
20.
Animal ; 18(3): 101084, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367312

RESUMO

Procedures such as transport and marketing can subject animals to water and feed deprivation and impair animal health and performance. Maintaining the mineral status of animals under these conditions can bring benefits to health and performance. The use of hydroxychloride mineral sources can improve mineral status, nutrient digestibility and performance. Two studies were conducted to investigate how the supplementation of 02 trace mineral sources of Cu and Zn and 48-hour water/feed deprivation would affect the performance and metabolism of grass-fed beef cattle. In the first study, 20 castrated and rumen-canulated Nellore steers (BW = 350 ±â€¯132 kg; 20 m) were distributed in individual pens, in a 2 × 2 factorial arrangement: supplemental Cu and Zn sources from inorganic vs hydroxychloride (HTM) and 48-hours deprivation (WFD) vs unrestricted (WFU) access to water and feed. The 57d of study was divided into two periods: (1) Adaptation from -21d to -1d and (2) evaluation from 0d to 36d. Interaction between deprivation × period was detected (P < 0.05) for digestibility of DM (DMD), organic matter (OMD), neutral detergent fiber (NDFD), and acid detergent fiber (ADFD). Deprivation increased DMD, OMD, NDFD, and ADFD immediately after the deprivation period (3-5d), but impaired digestibility at longer periods such as 11-13d and 32-34d. DM (DMI) and nutrient intake (P = 0.075), as well as NDFD were higher in HTM. Several ruminal parameters were affected by deprivation: short-chain fatty acids concentration decreased, while rumen pH increased (deprivation × time; P < 0.05); decreased propionate, butyrate and increased isobutyrate, isovalerate, and valerate in WFD (deprivation × time; P < 0.05), respectively. In the second study, eighty-four intact Nellore males (BW = 260 ±â€¯35 kg) were blocked by BW and randomly assigned to Urochloa brizantha cv. Marandu paddocks for 131d in a 2 × 2 factorial arrangement. Liver Cu was higher in WFU/HTM animals (mineral × deprivation; P < 0.05). Interaction between deprivation × period (P < 0.05) was detected for BW and average daily gain (ADG). On 2d and 12d after deprivation, WFD increased ADG and recovered the BW lost. In conclusion, water and feed deprivation imposed in these trials were able to impact several nutrient digestibility and ruminal fermentation parameters in short- and long-term. Performance was not affected by the studied factors. Furthermore, supplementation with sources of Cu and Zn hydroxychloride increased Cu in the liver and tended to increase DMI and NDFD.


Assuntos
Cobre , Zinco , Masculino , Bovinos , Animais , Suplementos Nutricionais , Dieta/veterinária , Água/metabolismo , Detergentes/metabolismo , Digestão , Minerais/metabolismo , Fermentação , Ração Animal/análise , Rúmen/metabolismo
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