628 research outputs found
Use of re-esterified palm oils, differing in their acylglycerol structure, in weaning-piglet diets
Re-esterified oils are new fat sources obtained from chemical esterification of acid oils with glycerol (both economically interesting by-products from oil refining and biodiesel industries, respectively). The different fatty acid (FA) positional distribution and acylglycerol composition of re-esterified oils may enhance the apparent absorption of saturated fatty acids (SFA) and, thus, their overall nutritive value. The aim of the present study was to investigate the potential use of re-esterified palm oils, in comparison with their corresponding acid and native oils, and also with an unsaturated fat source in weaning-piglet diets. The parameters assessed were: FA apparent absorption, acylglycerol and free fatty acid (FFA) composition of feces, and growth performance. One-hundred and twenty weaning piglets (average weight of 8.50 ± 1.778 kg) were blocked by initial BW (six blocks) and randomly assigned to five dietary treatments, resulting in four piglets per pen and six replicates per treatment. Dietary treatments were a basal diet supplemented with 10% (as-fed basis) of native soybean oil (SN), native palm oil (PN), acid palm oil (PA), re-esterified palm oil low in mono- (MAG) and diacylglycerols (DAG) (PEL), or re-esterified palm oil high in MAG and DAG (PEH). Results from the digestibility balance showed that SN reached the greatest total FA apparent absorption, and statistically different from PN, PA and PEL ( P 0.05), but PEH achieved the greatest total FA apparent absorption. Animals fed PEL, despite the fact that PEL oil contained more sn-2 SFA, did not show an improved absorption of SFA ( P > 0.05). Animals fed PA and PN showed similar apparent absorption coefficients ( P > 0.05), despite the high FFA content of PA oil. The acylglycerol and FFA composition of feces was mainly composed of FFA. There were no significant differences in growth performance ( P > 0.05). Results of the present study suggest that, despite the different acylglycerol structure of re-esterified oils, there were no significant differences in digestibility or performance with respect to their corresponding PN and PA oils in weaning-piglet diets.info:eu-repo/semantics/publishedVersio
Use of re-esterified palm oils, differing in their acylglycerol structure, in fattening pig diets
Re-esterified oils are new fat sources obtained from the chemical esterification of acid oils with glycerol (both economically interesting by-products from oil refining and biodiesel industries, respectively). The different fatty acid (FA) positional distribution and acylglycerol composition of re-esterified oils may enhance the apparent absorption of saturated fatty acids (SFA) and, therefore, their overall nutritive value, which might lead to an increased deposition of SFA. The aim of the present study was to investigate the potential use of re-esterified palm oils, in comparison with their corresponding acid and native oils in fattening pig diets, studying their effects on fatty acid apparent absorption, acylglycerol and free fatty acid (FFA) composition of feces, growth performance, carcass-fat depots and fatty acid composition of backfat. Seventy-two crossbred boars and gilts (average weight of 24.7 ± 2.55 kg) were blocked by initial BW (nine blocks of BW for each gender), housed in adjacent individual boxes, and fed one of the four dietary treatments, which were the result of a basal diet supplemented with 4% (as-fed basis) of native palm oil (PN), acid palm oil (PA), re-esterified palm oil low in mono- and diacylglycerols (PEL), or re-esterified palm oil high in mono- and diacylglycerols (PEH). Regarding results from the digestibility balance, PA and PN showed similar apparent absorption coefficients ( P > 0.05), despite the high, FFA content of the former. However, re-esterified palm oils (both PEL and PEH) showed a higher
apparent absorption of total FA than did their corresponding native and acid oils ( P 0.05). We conclude that re-esterified oils are interesting fat sources to be considered in fattening pigs.info:eu-repo/semantics/publishedVersio
Use of combinations of re-esterified oils, differing in their degree of saturation, in broiler chicken diets
Re-esterified oils contain higher proportions of mono- and diacylglycerols, and also higher proportions of saturated fatty acids (SFA) at the sn-2 position of acylglycerol molecules than does a native oil with the same degree of saturation, which enhances the apparent absorption of SFA. Moreover, as happens with native oils, their nutritive value could be further improved by blending re-esterified oils of extreme degrees of saturation. Therefore, the aim of the current study was to assess the effect of increasing the dietary unsaturated-to-saturated fatty acid ratio (UFA:SFA) by adding re-esterified soybean oil in replacement of re-esterified palm oil, on fatty acid (FA) apparent absorption and its consequences on growth performance, carcass fat depots, and FA composition of abdominal adipose tissue. For this purpose, one hundred twenty 1-day-old female broiler chickens were randomly distributed in 30 cages. The 2 pure re-esterified oils, together with 3 re-esterified oil blends, were included in the basal diet at 6%. The increasing dietary UFA:SFA ratio resulted in an improved total FA apparent absorption (linear effect for the starter period, P = 0.001; quadratic effect for the growerfinisher period, P = 0.006) and, therefore, an improved feed conversion ratio (FCR) for the overall period (linear effect, P = 0.003). In the starter period, the improved fat absorption was due to the growing presence of linoleic acid and the enhanced absorption of SFA, mono- and polyunsaturated FA (associative effects among FA; P 0.05). The UFA:SFA ratio of the abdominal adipose tissue varied in the same direction, but to a lesser extent than that of the diet. Whilst the deposited-to-absorbed ratio of polyunsaturated FA remained relatively constant as the dietary UFA:SFA ratio increased, the deposited-to-absorbed ratio of SFA increased, and that of monounsaturated FA decreased. Taken together, the addition of re-esterified
soybean oil in replacement of re-esterified palm oil improved fat absorption, but no synergism was observed between re-esterified oils.info:eu-repo/semantics/publishedVersio
Cyanobacterial calcification in modern microbialites at the submicrometer scale
International audienceThe search for microfossils in the geological record has been a long-term challenge. Part of the problem comes from the difficulty of identifying such microfossils unambiguously, since they can be morphologically confused with abiotic biomorphs. One route to improve our ability to correctly identify microfossils involves studying fossilization processes affecting bacteria in modern settings. We studied the initial stages of fossilization of cyanobacterial cells in modern microbialites from Lake Alchichica (Mexico), a Mg-rich hyperalkaline crater lake (pH 8.9) hosting currently growing stromatolites composed of aragonite [CaCO3] and hydromagnesite [Mg5(CO3)4(OH)2 * 4(H2O)]. Most of the biomass associated with the microbialites is composed of cyanobacteria. Scanning electron microscopy analyses coupled with confocal laser scanning microscopy observations were conducted to co-localize cyanobacterial cells and associated minerals. These observations showed that cyanobacterial cells affiliated with the order Pleurocapsales become specifically encrusted within aragonite with an apparent preservation of cell morphology. Encrustation gradients from non-encrusted to totally encrusted cells spanning distances of a few hundred micrometers were observed. Cells exhibiting increased levels of encrustation along this gradient were studied down to the nm scale using a combination of focused ion beam (FIB) milling, transmission electron microscopy (TEM) and scanning transmission x-ray microscopy (STXM) at the C, O and N K-edges. Two different types of aragonite crystals were observed: one type was composed of needle-shaped nano-crystals growing outward from the cell body with a crystallographic orientation perpendicular to the cell wall, and another type was composed of larger crystals that progressively filled the cell interior. Exopolymeric substances (EPS), initially co-localized with the cells, decreased in concentration and dispersed away from the cells while crystal growth occurred. As encrustation developed, EPS progressively disappeared, but remaining EPS showed the same spectroscopic signature. In the most advanced stages of fossilization, only the textural organization of the two types of aragonite recorded the initial cell morphology and spatial distribution
Fish oil rich in eicosapentaenoic acid and docosahexaenoic acid in sow diets modifies oxylipins and immune indicators in colostrum and milk
Colostrum and milk are the first nutrient sources for newborn piglets. In addition, n-3 fatty acids (FAs) and their oxygenated derivatives (oxylipins) have the capacity to modulate immune components. The aim of the current study was to include a fish oil rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in sow diets to promote an increase of anti-inflammatory molecules in colostrum and milk to benefit piglets. Thirty-six sows were randomly assigned from insemination to the end of lactation to either a control diet with animal fat (15 g/kg in gestation and 30 g/kg in lactation) or an n-3 diet in which animal fat was totally (gestation) or half (lactation) replaced by an equivalent amount of solid fish oil. Performance of sows and piglets was monitored during the study. Colostrum and milk samples were obtained after the birth of the first piglet and at weaning, respectively. From all samples (n = 18 per treatment), FAs were quantified by gas chromatography and immunoglobulins and cytokines by ELISA. Three samples per treatment were randomly selected to analyse oxylipin composition by liquid chromatography-tandem mass spectrometry. In colostrum and in milk, the n-3 FA (P = 0.020 and P < 0.001), particularly EPA (P < 0.001 and P < 0.001) and DHA (P < 0.001 and P < 0.001), and also their oxygenated derivatives were increased in samples from sows fed n-3 diet. Fish oil had no effect on immunoglobulin concentrations, but reduced tumour necrosis factor α (TNFα) (P = 0.011) and a tendency to reduce interleukin 10 (IL10) (P = 0.059) were observed in milk. In conclusion, fish oil in sow diets increased n-3 FA, particularly EPA and DHA, and their oxygenated derivatives in colostrum and milk, reducing TNFα and IL10 in milk.info:eu-repo/semantics/publishedVersio
Computed tomography evaluation of gilt growth performance and carcass quality under feeding restrictions and compensatory growth effects on the sensory quality of pork
Restricted feed can affect the body composition of pigs. Body composition can be studied non-destructively in live pigs using computed tomography (CT). The objective was to investigate the effect of different feeding restriction strategies on the productive and carcass quality parameters of gilts during growth via CT images and the effects of such strategies on meat quality, sensory properties and consumer preferences. Moreover, we sought to determine whether CT is a suitable tool for this purpose in this type of study. Thus, 36 Pietrain x (Large White x Landrace) gilts were assigned to the following three feeding strategies: 1) ad libitum feeding (AL) during all fattening periods (AL-AL); 2) AL feeding between 30 and 70 kg target body weight (TBW) followed by restriction (84% of AL) until 120 kg TBW (AL-RV); and 3) restriction feeding (78% of AL) between 30 and 70 kg TBW followed by AL until 120 kg TBW (RV-AL). When the pigs reached 30, 70, 100 and 120 kg, they were CT scanned to obtain the carcass composition parameters. At 120 kg TBW, the pigs were slaughtered, and the carcass and meat quality was determined. The loins were collected for trained panel evaluation and consumer tests. The panellists evaluated the odour, flavour and texture attributes of cooked loins. A total of 120 consumers scored the overall acceptability, tenderness, odour and flavour. The results showed a decrease of 76% and 80% in the average daily gain and average daily feed intake during the restriction period compared with the ad libitum in the growth phase, respectively, and a decrease of 89% and 87% in these parameters during the fattening phase, respectively. A restriction reduces the body fat content during the period of the restriction. Differences in the carcass and cut composition and meat quality were not observed at the end of the experiment among the treatments. Regarding sensory quality, meat from the animals in the AL-AL treatment was tougher than that from animals in the RV-AL and AL-RV treatments. Nevertheless, these differences were not detected by consumers, who did not provide significantly different scores for acceptability. Thus, when preparing feeding strategies, these results should be considered to optimize costs and increase benefits. Furthermore, computed tomography represents a non-destructive technology suitable for determining carcass composition before slaughter.info:eu-repo/semantics/acceptedVersio
Re-esterified Palm Oils, Compared to Native Palm Oil, do not Alter Fat Absorption, Postprandial Lipemia or Growth Performance in Broiler Chicks
Re-esterified palm oils are obtained from the chemical esterification of palm acid oils (rich in free fatty acids) with glycerol, both economically interesting by-products from oil refining and biodiesel industries, respectively. Thus, re-esterified palm oils could be an economically interesting alternative to native palm oil in broiler chick diets. However, because they may have different physicochemical properties than have their corresponding native oil, we assessed the effect of fatty acid (FA) positional distribution within acylglycerol molecules and the effect of acylglycerol composition on FA apparent absorption, and their possible consequences on the evolution of postprandial lipemia and growth performance in broiler chicks. Seventy-two 1-day-old female broiler chicks were randomly distributed into 18 cages. The three treatments used were the result of a basal diet supplemented with 6 wt% of native palm oil (N-TAG), re-esterified palm oil (E-TAG), or re-esterified palm oil high in mono- and diacylglycerols (E-MDAG). Chemical esterification raised the fraction of palmitic acid at the sn -2 position from 9.63 mol% in N-TAG oil to 17.9 mol% in E-TAG oil. Furthermore, E-MDAG oil presented a high proportion of mono- (23.1 wt%) and diacylglycerols (51.2 wt%), with FA mainly located at the sn -1,3 positions, which resulted in a lower gross-energy content and an increased solid-fat index at the chicken's body temperature. However, re-esterified palm oils did not alter fat absorption, postprandial lipemia, or growth performance, compared to native palm oil, so they can be used as alternative fat sources in broiler chick diets
One-pot growth of metal-organic frameworks on polymers for catalytic performance enhancement in the CO2 cycloaddition to epoxides
A novel approach is reported to prepare 3D-printed polymers that incorporate metal-organic frameworks (MOFs) through a one-pot growth process, involving covalent grafting and growth onto 3D polymeric surfaces. The resulting hybrid materials were subjected to comprehensive characterization using techniques such as SEM, XRD, FTIR, Raman, and XPS. The findings demonstrated an excellent dispersion of the inorganic units on the polymer matrix while preserving their metal-organic structure. The hybrid materials exhibited the presence of Lewis acid and basic groups within the MOF. The catalytic performance of these hybrid materials was evaluated in the mild cycloaddition reaction of carbon dioxide (CO2) to epoxides. Notably, the polymers incorporating UiO-67 MOFs displayed remarkable activity, even at low CO2 pressures and in the absence of auxiliary co-catalysts or additives. The catalytic activity of these hybrid materials exhibited a significant improvement, up to two orders of magnitude higher than analogous bulk MOFs. This observation highlights the superior performance of the 3D-printed polymer/MOF hybrids in this catalytic transformation
The effect of feeder system and diet on welfare, performance and meat quality, of growing-finishing Iberian × Duroc pigs under high environmental temperatures
The present study investigated the replacement of 5% of starch (ST) by 5% of sunflower oil (SO), with or without feed restriction, in the diet of growing-finishing Iberian × Duroc pigs exposed to heat stress conditions. The effects of these strategies on the welfare, performance and meat quality of the animals were evaluated. Seventy-two crossbred males [51.00 ± 6.29 kg body weight (BW)] were housed in collective pens and randomly distributed according to their initial BW in climate-controlled rooms under heat stress conditions (30–32 °C; 35%–50% humidity). The experiment was carried out in a randomized block design, in a 2 × 2 factorial design composed of two diets (control or oil) and two feed management (ad-libitum and restriction) types. The investigated treatments were: 1) control diet (5% ST × 0% SO) with ad-libitum feed intake, 2) oil diet (replacement of 5% of ST by 5% SO) with ad-libitum feed intake, 3) control diet with restriction feed intake, and 4) oil diet with restriction feed intake. The pigs’ behavior and dirtiness score were observed daily, and their performance was assessed weekly. Furthermore, three blood samples were collected from each animal for hemogram analysis during the period of study. The analysis of meat and carcass quality was performed 24 h post-mortem once the animals had reached an average BW of 130–140 kg. Statistical analyses were performed using the PROC MIXED and PROC GENMOD procedures of the Statistical Analysis System (SAS). The diet-regimen interaction produced no effects (P > 0.05) on the analyzed variables, except for behavior. Animals on the control diet associated with ad-libitum feed management spent more time in the lateral decubitus position and showed reduced activity. In addition, pigs fed ad-libitum and those that received the control diet displayed the highest level of dirtiness during the experiment. Evaluation of performance revealed that pigs receiving the oil diet showed reduced feed intake (P < 0.05) with no difference in average daily gain and consequently presented better feed conversion values compared to animals on the control diet. Furthermore, the oil diet resulted in a higher (P < 0.05) carcass yield as well as a higher oleic fat content in the meat. Pigs on restricted feeding management with lower body and carcass weights produced higher values of leanness percentage and carcass compared to animals in the ad-libitum group. In conclusion, the replacement of 5% of starch by 5% of sunflower oil in the pigs’ diet during high ambient temperatures improved the animals’ welfare, feed efficiency, and carcass characteristics.info:eu-repo/semantics/acceptedVersio
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