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51.
The digestive capacity of the Portuguese native breed of Barrosão cattle and the Holstein–Friesian breed was measured when fed meadow hay (72–74 g CP and 641–671 g NDF/kg dry matter), offered either alone or supplemented with soya bean meal (150 g/kg dry matter), at maintenance level. Four mature cows of each breed were used. Average initial live weight (LW) was 457 and 635 kg for the Barrosão and the Holstein–Friesian cows respectively. The organic matter digestibility (OMD) of the meadow hay was higher in Holstein–Friesian than in Barrosão cows (p < 0.08) whether supplemented or not. The neutral detergent fibre digestibility of the hay was also higher in Holstein–Frisian when the hay was fed alone (p < 0.08). The soya bean meal supplementation increased the OMD and the NDFD digestibility of the total diet (p < 0.05), but not the OMD digestibility of the hay (p > 0.05). The results obtained in this study suggest a higher ability to digest fibre in the large dairy breed than in the small native breed. This suggestion is also supported by previous findings with sheep breeds largely differing in mature live weight.  相似文献   
52.
The objective of this study was to evaluate the effect of three sources of glycerine (crude glycerine from soya bean oil – CGSO, mixed crude glycerine from frying oil and lard – MCG, and a semipurified glycerine from soya bean oil – SPGSO) in four concentrations in the diet (17.5, 35.0, 52.5 and 70.0 g of each type of glycerine per kg of feed) on the levels of plasmatic glycerol and the activity of the hepatic enzyme glycerol kinase in broilers of 22–35 days old (experiment I) and 33–42 days old (experiment II). The highest (p < 0.05) plasmatic glycerol level was detected in broilers fed diet containing CGSO. Independent of the source, increasing the concentration of glycerine led to a linear increase (p < 0.05) in the plasmatic glycerol concentration. In experiment I, all the diets containing glycerine resulted in increased concentrations of plasmatic glycerol, in relation to the control diet without glycerine. However, in experiment II, only the diet containing 17.5 g of CGSO per kg of feed and the diets formulated with any of the three types of glycerine in the inclusion concentrations of 35, 52.5 and 70 g/kg of feed resulted in higher plasmatic glycerol levels than those observed in the control broilers. The source of glycerine influenced the glycerol kinase activity only in experiment II, where the use of CGSO in the diet increased the enzyme activity. For both experiments, the glycerol kinase activity increased with the inclusion of glycerine in the diet. In conclusion, based on the absence of saturation of the glycerol kinase activity for the three glycerine sources and for both rearing periods evaluated, the broilers can metabolize the glycerol (at the level of the phosphorylation of the glycerol to glycerol‐3‐phosphate in the liver) present in the glycerine when the diet is supplemented with up to 70 g of glycerine per kg of feed.  相似文献   
53.
The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.  相似文献   
54.
ABSTRACT:   Seawater fishes are affected by a pathology commonly called 'myxobacteriosis', caused by Tenacibaculum maritimum (formerly Flexibacter maritimus ). The disease is characterized by fin erosion and necrotic ulcers of skin and muscle, and by low but constant mortality in cultured marine fish; in Italy is one of the most important and widely spread diseases affecting sea bass Dicentrarchus labrax , gilthead seabream Sparus aurata , sharp-snouted bream Diplodus puntazzo , white bream Diplodus sargus , and six-tooted bream Dentex dentex . In order to obtain an effective vaccine against the disease, formalin killed cells (FKC), extracellular products (ECPs) and crude lipopolysaccharide (LPS) preparations were obtained from the T. maritimum strain SPVId and injected intraperitoneally twice into the sea bass. The fish immune response to the preparations was studied: agglutinating antibody titer and in vitro phagocytosis were determined after the first and second injection in order to evaluate whether the preparations are immunogenic or not and if the booster effect took place. The results show that FKC and LPS preparations increased the antibody titer after the first injection when compared to the control sea bass. Moreover, all the preparations stimulated a secondary (booster) response. In vitro phagocytosis of the total blood was significantly higher for all the preparations when compared to the controls, but the crude LPS immunized sea bass showed the highest activity.  相似文献   
55.
56.
  1. Detailed knowledge about the distribution of species in need of protection is required for the management of Marine Protected Areas, a major tool to reduce marine biodiversity loss. Such knowledge is deficient for most marine invertebrates.
  2. Axinella polypoides is a marine sponge included on the list of protected species by the Barcelona Convention (1976) and the Bern Convention (1987). This large and erect species has an important ecological role in habitat forming and benthic–pelagic coupling.
  3. Bathymetrical, geographical and ecological data over the last 60 years were collated from publications and reports, together with new surveys to assess the distribution and protection status in Liguria of A. polypoides. It identified a more widespread distribution than previously thought, which points at a general need for dedicated investigations on the occurrence of species that require protection.
  4. Bathymetrical distribution was trimodal, with peaks corresponding to different geomorphological settings: coastal cliff bases (around 38 m depth), inner shelf shoals (52 m) and rocks amidst coarse sediment on the outer shelf (79 m). Density was significantly greater at the shallowest depths. The species was mostly found in the coralligenous biocoenosis, in association with other characteristic species or forming a monospecific facies.
  5. On (sub)vertical cliffs, A. polypoides often exhibited an unusual cane shape, rather than the typical bushy morphology, thus causing confusion with the congeneric A. cannabina, a more southern species. Records of the latter in the Ligurian Sea therefore need confirmation.
  6. Only a minority (22.6%) of A. polypoides records were in Marine Protected Areas, the remainder being located in areas with no current environmental protection plans in place. While the occurrence of this species in MPAs remained stable over the decades, the only quantitative historical data available indicated that populations in non-protected areas were declining owing to anthropogenic impacts (fishing and anchoring).
  相似文献   
57.
58.
Surface-associated marine bacteria are an interesting source of new secondary metabolites. The aim of this study was the isolation and identification of epiphytic bacteria from the marine brown alga, Bifurcaria bifurcata, and the evaluation of the antioxidant and antimicrobial activity of bacteria extracts. The identification of epiphytic bacteria was determined by 16S rRNA gene sequencing. Bacteria extracts were obtained with methanol and dichloromethane (1:1) extraction. The antioxidant activity of extracts was performed by quantification of total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC). Antimicrobial activities were evaluated against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae and Candida albicans. A total of 39 Bifurcaria bifurcata-associated bacteria were isolated and 33 were identified as Vibrio sp. (48.72%), Alteromonas sp. (12.82%), Shewanella sp. (12.26%), Serratia sp. (2.56%), Citricoccus sp. (2.56%), Cellulophaga sp. (2.56%), Ruegeria sp. (2.56%) and Staphylococcus sp. (2.56%). Six (15.38%) of the 39 bacteria Bifurcaria bifurcata-associated bacteria presented less than a 90% Basic Local Alignment Search Tool (BLAST) match, and some of those could be new. The highest antioxidant activity and antimicrobial activity (against B. subtilis) was exhibited by strain 16 (Shewanella sp.). Several strains also presented high antimicrobial activity against S. aureus, mainly belonging to Alteromonas sp. and Vibrio sp. There were no positive results against fungi and Gram-negative bacteria. Bifurcaria bifurcata epiphytic bacteria were revealed to be excellent sources of natural antioxidant and antimicrobial compounds.  相似文献   
59.
Extracts of five halophytes from southern Portugal (Arthrocnemum macrostachyum, Mesembryanthemum edule, Juncus acutus, Plantago coronopus and Halimione portulacoides), were studied for antioxidant, anti-inflammatory and in vitro antitumor properties. The most active extracts towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were the methanol extracts of M. edule (IC50 = 0.1 mg/mL) and J. acutus (IC50 = 0.4 mg/mL), and the ether extracts of J. acutus (IC50 = 0.2 mg/mL) and A. macrostachyum (IC50 = 0.3 mg/mL). The highest radical scavenging activity (RSA) against the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical was obtained in the ether extract of J. acutus (IC50 = 0.4 mg/mL) and H. portulacoides (IC50 = 0.9 mg/mL). The maximum total phenolic content (TPC) was found in the methanol extract of M. edule (147 mg gallic acid equivalents (GAE)/g) and in the ether extract of J. acutus (94 mg GAE/g). Significant decreases in nitric oxide (NO) production were observed after incubation of macrophages with lipopolysaccharide (LPS) and the chloroform extract of H. portulacoides (IC50 = 109 µg/mL) and the hexane extract of P. coronopus (IC50 = 98.0 µg/mL). High in vitro cytotoxic activity and selectivity was obtained with the ether extract of J. acutus. Juncunol was identified as the active compound and for the first time was shown to display selective in vitro cytotoxicity towards various human cancer cells.  相似文献   
60.
Agroforestry has been suggested to produce an array of ecological and socio-economic benefits that not only reach their adopters, but society as a whole. In spite of strong evidence of the benefits of agroforestry, there is a lack of understanding of the public perceptions of those benefits, which prevents the development of benefit-based promotion strategies of agroforestry products. Thus, this study examines the awareness of these benefits among residents and explores whether perceptions vary across individuals with different socio-demographic characteristics. An on-line platform was used to survey three panels of residents from Missouri, Pennsylvania and Texas. Overall, respondents had a neutral perception of the importance of the ecological and socio-economic benefits that agroforestry farms provide to society when compared to farms employing conventional agricultural practices. These results stress the need to increase public awareness of agroforestry practices and their benefits to more strategically position their products among the final consumer. Gender, education level, and residence location were significantly associated with the perceived ecological benefits produced by agroforestry farms and to a lesser extent with the socio-economic benefits. Results also showed that females and young individuals have a greater awareness of several benefits produced by agroforestry farms. Critical marketing implications to stimulate the purchase of agroforestry products (e.g., berries, nuts) among specific groups of consumers are discussed.  相似文献   
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