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1.
Antibiotics (Basel) ; 10(1)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435299

RESUMO

The aim of this study was to investigate the opinions of meat consumers (n = 1780) on on-farm management of unhealthy pigs, whether support for treatment with antibiotics varies according with chance of recovery, and the effect of knowledge on the use of antibiotics on these opinions. Most participants believed that the use of antibiotics was the best solution for unhealthy pigs, and this was associated with a low level of knowledge about antibiotics. Increasing the probability of recovery after treatment increased support for treating pigs with antibiotics. However, the majority of participants rejected the consumption of meat from animals housed in "hospital pens". After price, concern with food safety was the second main factor that influenced participants' choice when buying meat. Support for the use of antibiotics to deal with unhealthy pigs in "hospital pens", as well as for consumption of the meat from these animals, was higher among participants involved in agriculture. This shows that consumers are unaware of the potential negative repercussions for animal welfare associated with banning or reducing the use of antibiotics in livestock production, which is an important concern for the industry.

2.
Polymers (Basel) ; 12(8)2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823714

RESUMO

The poultry industry, highly prevalent worldwide, generates approximately 7.7 × 106 metric tons of chicken feathers (CFs), which become a major environmental challenge due to their disposal when considered waste or due to their energy transformation consumption when considered by-products. CFs are mainly composed of keratin (approximately 90%), which is one of the most important biopolymers whose inherent characteristics make CFs suitable as biopolymer fibers (BPFs). This paper first assesses the morphological and chemical characteristics of these BPFs, through scanning electron microscopy and energy dispersive X-ray spectroscopy, and then evaluates the waste valorization of these BPFs as a sustainable alternative for fiber-reinforcement of earthen mixes intended for earthen construction, such as adobe masonry, rammed earth, and earthen plasters. In particular, four earthen mixes with increasing doses of BPFs (i.e., 0%, 0.25%, 0.5%, and 1% of BPFs by weight of soil) were developed to evaluate the impact of BPF-reinforcement on the capillary, mechanical, impact, and abrasion performance of these earthen mixes. The addition of BPFs did not significantly affect the mechanical performance of earthen mixes, and their incorporation had a statistically significant positive effect on the impact performance and abrasion resistance of earthen mixes as the BPF dose increased. On the other hand, the addition of BPFs increased the capillary water absorption rate, possibly due to a detected increment in porosity, which might reduce the durability of water-exposed BPF-reinforced earthen mixes, but a statistically significant increment only occurred when the highest BPF dose was used (1%).

3.
Animals (Basel) ; 9(12)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842505

RESUMO

The present study used surveys of the cattle sector over the period of 2009-2015 to develop a typology of cattle farms to evaluate their evolution over time and to identify variables that may be associated with systems' adaptive changes and continuance. Four groups of farms were defined using multivariate analyses as follows: Group I are small calf-cow operations using non-specialized beef breeds; Group II is similar to Group I but employs specialized beef breeds; Group III is dedicated to finishing cattle, and Group IV are larger farms (>1000 animals) with a complete cycle of breeding and fattening. In general, beef cattle production in the temperate-Mediterranean Southern Zone of Chile is declining in response to the opening up of the economy that allows for ample imports, the high opportunity cost of land, and recurrent droughts associated with climate change. Current policies and regulations have modified farms' businesses models depending on their ease of access to markets, farm size and financial capacity. The defined groups require different development paths and strategies. Sustainable intensification is an alternative strategy for farms in Group I and II, particularly if they were to contract the finishing stage of their cattle with Group III farms. In contrast, it is suggested that Group IV farms concentrate on pastoral production using low external inputs to enhance the production of "natural" beef for high-value niche markets, with positive externalities.

4.
Animals (Basel) ; 9(9)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533372

RESUMO

The aim of this study was to characterize the routine care, training, feeding, and nutritional management of Chilean corralero horses that participated in the rodeos of the Chilean Rodeo Federation. Forty-nine horse farms between the Metropolitan (33°26'16″ south (S) 70°39'01″ west (W)) and Los Lagos Regions (41°28'18″ S 72°56'12″ W), were visited and a survey was conducted on the management and feeding of the Chilean horse. Of the horses which participated in at least one official rodeo in the 2014-2015 season, 275 horses were included in the study. The survey consisted of five questions about general data on the property and the respondent, four questions on the animal characteristics, five questions about where the horses were kept during the day, seven questions to characterize the amount of exercise done by the horse, and 18 questions about feeding practices; additionally, the amount of feed offered was weighed. All horses in this study were in training and kept in their stall for at least 12 h and remained tied or loose for the rest of the day. The intensity of daily exercise of the rodeo Chilean horse could be classified as moderate to heavy and consisted of being worked six days/week and participating in two rodeos/month. Ninety-eight percent of respondents had watering devices in the stables. The diet of the Chilean corralero horse during the training season is based on forages, mainly alfalfa hay, plus oats as an additional energy source. Protein supplements such as oil seed by-products are used less frequently. A wide variation was observed in the diets and quantities of feed offered, which suggests that the feeding management of these individuals is not formulated according to their requirements.

5.
J Environ Qual ; 48(2): 430-438, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30951109

RESUMO

There is high demand for identifying socio-environmentally sound ways to dispose of large quantities of offensive odor-generating organic residues produced by intensive livestock farming. The use of these residues as amendments at large-scale mine tailings storage facilities for in situ plant-based reclamation may be a useful alternative. We performed a greenhouse assay to evaluate effectiveness of pig slurries and the solid organic fraction of aerobic-aerated pig slurries, both treated and not treated for odor emission, as amendments for copper tailings. Different doses of slurries or the solid organic fraction of the slurries, untreated and treated with either ozone or a commercial product used to manage strong odors (Just a Drop), were incorporated into tailings and stabilized (15 d) under greenhouse conditions. L. (ryegrass) was used as bioindicator for Cu and Zn toxicity. Plant performance (shoot and root dry biomass, Cu and Zn content in leaves) and general physicochemical characteristics of substrates were evaluated. Our results showed that odor management of pig residues was possible with commercial products, and their incorporation into tailings rapidly and effectively reduced odor emission. The solid organic fraction of the slurries neutralized acidic tailings, and both pig residues increased organic matter and nutrient content in tailings while reducing extractable Cu. As a result, ryegrass productivity was significantly improved by incorporation of either slurries or their solid organic fraction into tailings in a dose-dependent form. Foliar Cu content in ryegrass was not affected but foliar Zn content increased; however, Zn remained within acceptable ranges. Both the pig slurries and their soil organic fractions proved to be valuable residues for tailings reclamation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Esterco , Mineração , Poluentes do Solo/química , Biodegradação Ambiental , Cobre
6.
J Environ Manage ; 230: 311-318, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30292019

RESUMO

The present study assesses the effect of tailing texture (loamy sand (LT) and sandy loam (ST)), dose of pig sludge (0, 50, 100 and 200 t ha-1) and amendment-contact time (14, 28 and 42 days) on physicochemical quality of amended substrate using Lolium perenne var Nui as a bioindicator. The main properties of LT differed of ST in levels of total organic carbon (0.19 and 0.58%), in pH (4.6 and 8.5), total Cu (202 and 1647 mg kg-1) and Zn content (31 and 137 mg kg-1). Soil pore water of experimental substrates was characterized for pH, electrical conductivity (EC) and Cu2+ ion activity (pCu2+) while ammonium nitrogen (NH4+-N), infiltration rate and general physicochemical characteristics were measured in substrates. Shoot biomass (SB), root biomass (RB) and the RB:SB ratio was calculated for L. perenne. The results showed there to be a significant interaction (p < 0.05) between tailing texture, sludge dose and amendment-contact time for pCu2+, infiltration rate, SB, RB, and RB: SB ratio, but not for pH, EC, or NH4+-N. However, sludge dose and amendment-contact time significantly affected all variables. By increasing dosages of pig sludge, pore water pH increased, and this was associated with decreases in pCu2+ and the infiltration rate. High doses of pig sludge (100 and 200 t ha-1) impaired growth of L. perenne irrespective of tailing texture and amendment-contact time, likely because of the rise of EC (up to 14 mS cm-1). For both tailing textures, the highest biomass was obtained after incorporation of 50 t ha-1 of pig sludge, with increasing values as amendment-contact time rose. In conclusion, effective management of pig sludge for tailing reclamation should guarantee doses <50 t ha-1 and amendment-contact time >28 days, irrespective of tailing texture.


Assuntos
Esgotos/química , Animais , Biomassa , Lolium/química , Nitrogênio/química , Solo/química , Suínos , Fatores de Tempo
7.
Exp Biol Med (Maywood) ; 240(9): 1158-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25711878

RESUMO

Morbid obesity is a worldwide health concern that compromises life quality and health status of obese human subjects. Bariatric surgery for treating morbid obesity remains as one of the best alternatives to promote excess weight loss and to reduce co-morbidities. We have not found studies reporting nutrients and energy balance considering digestibility trials in humans following surgery. The purpose of this study was to determine protein, lipid, fiber, energy, calcium, and phosphorous digestibility in a swine model that underwent ileal transposition (IT), sleeve gastrectomy with ileal transposition (SGIT), Roux-en-Y gastric bypass (RYGBP), and with sham operated animals (SHAM). Thirty-two pigs were randomly assigned to four laparoscopic procedures: IT (n = 8), RYGBP (n = 8), SGIT (n = 8), and Sham-operated pigs (n = 8). From day 0 postsurgery to 130, pigs were weighed monthly to determine live weight and weight gain was calculated for each month postsurgery until day 130. Food intake in a metabolic weight basis was calculated by measuring ad libitum food intake at day 130. Swine were fitted into metabolic crates to determine digestibility coefficients of dry matter, protein, fat, fiber, ash, energy, calcium, and phosphorous from day 130. A one-way ANOVA and Student-Newman-Keuls were used to detect differences in weight, food intake, and digestibility coefficients. Digestibility values for dry matter, fiber, phosphorus, and energy showed no differences among groups (P > 0.05). However, significant differences (P ≤ 0.05) were encountered among groups for fat, protein, ash, and calcium digestibilities. The RYGBP procedure, when applied to the pig model, significantly reduced calcium, fat, and ash digestibility, which did not occur with SGIT or IT procedure, when compared with Sham-operated animals.


Assuntos
Cirurgia Bariátrica/métodos , Digestão , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cirurgia Bariátrica/efeitos adversos , Ingestão de Alimentos , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Derivação Gástrica/efeitos adversos , Derivação Gástrica/métodos , Humanos , Derivação Jejunoileal/efeitos adversos , Derivação Jejunoileal/métodos , Síndromes de Malabsorção/fisiopatologia , Masculino , Modelos Animais , Obesidade Mórbida/patologia , Obesidade Mórbida/fisiopatologia , Obesidade Mórbida/cirurgia , Sus scrofa/fisiologia , Sus scrofa/cirurgia
8.
Anim Reprod Sci ; 116(3-4): 318-25, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19304413

RESUMO

Plasma concentrations of progesterone (P4), estradiol-17beta (E2), estrone (E1) and estrone sulfate (E1S) were measured during gestation in eight guanacos kept in captivity. Gestational length was 346.1+/-9.8 days. P4 plasma concentrations increased after ovulation and remained elevated until parturition. However, during the last 4 weeks of gestation, a gradual decrease from 4.17x1.17(+/-1)nmol/L to 2.02x1.95(+/-1)nmol/L on day 5 before parturition was observed, followed by a more abrupt final decline to baseline concentrations which were reached on the day after parturition. Mean E2 plasma concentrations started to increase during the eighth month of gestation, and were significantly elevated up to maximum concentrations of 484.7x1.21(+/-1)pmol/L during the last 2 months of pregnancy. Concentrations returned to baseline during the last 2 days of gestation. An increase of E1S concentrations (p<0.01) was observed in the eleventh month of gestation. Mean E1S concentrations remained rather constant during the last 3 weeks of gestation between 4 to 8nmol/L until parturition, when a steep precipitous decline was observed. E1 concentrations were slightly elevated during the last 4 weeks of gestation, however, maximum concentrations did not exceed 1.5nmol/L. The results show distinct species specific features of gestational steroid hormone profiles in the guanaco in comparison to domestic South American camelids, such as a more pronounced gradual prepartal decrease of P4 concentrations prior to the final decline to baseline, and clearly lesser E1S concentrations during the last 4 weeks of gestation, which lack a continuous prepartal increase.


Assuntos
Camelídeos Americanos/fisiologia , Sistema Endócrino/fisiologia , Hormônios/sangue , Parto/sangue , Período Pós-Parto/sangue , Prenhez , Animais , Camelídeos Americanos/sangue , Sistema Endócrino/metabolismo , Estradiol/sangue , Feminino , Masculino , Gravidez , Prenhez/sangue , Progesterona/sangue
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