scholarly journals Artificial rearing of pigs

1979 ◽  
Vol 41 (1) ◽  
pp. 85-93 ◽  
Author(s):  
M. J. Newport ◽  
J. E. Storry ◽  
B. Tuckley

1. Pigs were weaned at 2 d of age and fed on a milk substitute at hourly intervals. They were slaughtered at 28 d of age.2. The diets contained 730 g dried skim-milk and 270 g fat/kg dry matter (DM). Three diets were compared in which the fat was supplied as soya-bean oil (SO) (diet A), equal amounts of SO and medium-chain triglyceride (MCT) (diet H), or 246 g MCT and 24 g SO (diet I)/kg DM. In the latter diet, SO ensured that the diet had an adequate content of essential fatty acids.3. Growth rate (2–28 d of age) was reduced (P < 0.05) by the high-MCT diet (diet I) compared with the medium-MCT diet (diet H), but in comparison with diet A, the differences were not significant (P > 0.05). The feed: gain ratio (g DM consumed/g live-weight gain) was not affected by the type of dietary lipid.4. Diet I increased the proportion of crude protein (nitrogen × 6.25) (g/kg wet weight) in the carcass but did not increase N retention (g/d per kg live weight). The proportion of fat in the carcass was reduced, particularly by diet I (P < 0.001), and was inversely related to an increase mainly in the water content, and to a lesser extent, in the crude protein content of the carcass. The liver weight (g/kg live wt) was greatly increased by MCT (P < 0.01 or P < 0.001).5. Approximately 20, 44 and 80% of the fatty acids in the carcass of pigs on the SO, diet H and diet I respectively could not have been derived from direct deposition of the dietary fatty acids, but rather by de novo synthesis from carbohydrate or elongation of shorter-chain fatty acids.MCT increased the concentrations in the blood, taken 1 h after feeding, of total lipid, phospholipid, cholesterol and cholesterol ester, indicating incomplete oxidation of the caprylic and caprylic and capric acids in MCT by the liver, and their incorporation, after chain elongation, into plasma lipids.

1995 ◽  
Vol 269 (2) ◽  
pp. E247-E252 ◽  
Author(s):  
H. O. Ajie ◽  
M. J. Connor ◽  
W. N. Lee ◽  
S. Bassilian ◽  
E. A. Bergner ◽  
...  

To determine the contributions of preexisting fatty acid, de novo synthesis, and chain elongation in long-chain fatty acid (LCFA) synthesis, the synthesis of LCFAs, palmitate (16:0), stearate (18:0), arachidate (20:0), behenate (22:0), and lignocerate (24:0), in the epidermis, liver, and spinal cord was determined using deuterated water and mass isotopomer distribution analysis in hairless mice and Sprague-Dawley rats. Animals were given 4% deuterated water for 5 days or 8 wk in their drinking water. Blood was withdrawn at the end of these times for the determination of deuterium enrichment, and the animals were killed to isolate the various tissues for lipid extraction for the determination of the mass isotopomer distributions. The mass isotopomer distributions in LCFA were incompatible with synthesis from a single pool of primer. The synthesis of palmitate, stearate, arachidate, behenate, and lignocerate followed the expected biochemical pathways for the synthesis of LCFAs. On average, three deuterium atoms were incorporated for every addition of an acetyl unit. The isotopomer distribution resulting from chain elongation and de novo synthesis can be described by the linear combination of two binomial distributions. The proportions of preexisting, chain elongation, and de novo-synthesized fatty acids as a percentage of the total fatty acids were determined using multiple linear regression analysis. Fractional synthesis was found to vary, depending on the tissue type and the fatty acid, from 47 to 87%. A substantial fraction (24-40%) of the newly synthesized molecules was derived from chain elongation of unlabeled (recycled) palmitate.


1972 ◽  
Vol 50 (10) ◽  
pp. 1263-1267 ◽  
Author(s):  
K. R. Penner ◽  
J. S. Barlow

The fatty acid composition of newly emerged Ips paraconfusus Lanier shows no sexual dimorphism and is approximately as follows: C14:0, 0.5%; C16:0, 23.0%; C16:1, 6%; C18:0, 3%; C18:1, 55%; C18:2, 9%; C18:3, 2%. Both sexes, but particularly the female, use up fatty acids, particularly the monounsaturated acids, during reproduction. Isotope from 1-14C-acetate injected into newly emerged females appeared in all saturated and monounsaturated fatty acids within 30 min. There was evidence of de novo synthesis of C14:0 and C16:0, chain elongation of C16:0 to C18:0, and desaturation of C16:0 and C18:0 to yield C16:1 and C18:1 respectively.


1980 ◽  
Vol 44 (2) ◽  
pp. 161-170 ◽  
Author(s):  
M. J. Newport ◽  
H. D. Keal

1. Spray-dried diets were prepared containing (g/kg): dried skim-milk 665, dried whey 65, soya-bean oil 270 (diet U); or single-cell protein (Pruteen; SCP) 308, dried whey 440, soya-bean oil 252 (diet X). The diets had a crude protein (nitrogen × 6·25) content (g/kg) of 250 (diet U) and 240 (diet X), excluding nucleic acids (36 g/kg) in diet X.2. The diets were reconstituted (200 g dry matter/l) and mixtures of diets U and X prepared to give diets supplying 0 (diet U), and approximately 400 (diet V), 600 (diet W) and 800 (diet X) g crude protein from SCP/kg total protein. All diets were supplemented with vitamins, and minerals to equalize the calcium, phosphorous, sodium and potassium concentrations.3. Pigs weaned at 2 d of age were given the diets at hourly intervals on a scale based on live weight. At 28 d age the experiment was terminated and pigs killed 1 h after a feed for a study of protein digestion. Polyethylene glycol (PEG) was fed in the diets (0.5 g/l) for 24 h before slaughter.4. Performance of pigs fed on diet V was as good as on the all-milk diet U. Greater levels of replacement by SCP (diets W and X) reduced performance. Mortality was greater on the all-milk diet, but protein source had no effect on the incidence of scouring. N retention (g/d per kg live weight) was similar for all diets but declined with age.5. SCP appeared to stimulate secretion of pepsin and chymotrypsin, and reduced the pH value in digesta in the stomach. Enzyme adaptation may have been insufficient to digest high levels of SCP in the diet, and together with the decreased transit time observed using PEG as a marker, may account for the poorer performance when 600 or 800 g/kg milk protein was replaced.6. Nucleic acids from SCP were metabolized and not retained for tissue synthesis. Allantoin excretion accounted for 75% of the theoretical maximum for complete excretion of nucleic acids, and uric acid excretion was also increased.


2020 ◽  
Vol 375 (1804) ◽  
pp. 20200039 ◽  
Author(s):  
Laura Helenius ◽  
Suzanne M. Budge ◽  
Heather Nadeau ◽  
Catherine L. Johnson

The essential fatty acids (EFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are critical nutrients for all organisms, and the temperature sensitivity of their trophic transfer in marine systems is of concern because of rising ocean temperatures. Laboratory-reared copepodites of the marine calanoid Calanus finmarchicus were used to test the effects of temperature (at 6°C, 12°C and increasing temperature stress) and prey type (the dinoflagellate Heterocapsa triquetra and the diatom Thalassiosira weissflogii ) on the extent and efficiency of dietary EPA and DHA incorporation from phytoplankton to copepods in a set of feeding experiments using 13 C labelling. Temperature was a significant determinant of C . finmarchicus copepodites' EFA incorporation and gross growth efficiency, defined as the fraction of ingested EFA retained in copepod tissue. Ingestion and incorporation of both EFA were higher at warmer temperature, except in the case of DHA in copepods feeding on diatoms. DHA-associated growth efficiency was higher at the higher temperature for copepodites consuming the dinoflagellate, but temperature-related variation in algal EFA content was also a predictive factor. Moreover, our results strongly suggest that copepodites are capable of synthesizing EPA when consuming an EPA-depleted diet. Our study implies that the copepod link of marine food webs is resilient in terms of EFA transfer when confronted with alterations of ambient temperature and prey type availability. Measurements presented here are critical for estimating how EFA transfer dynamics respond to intra- and interannual environmental variability. This article is part of the theme issue ‘The next horizons for lipids as ‘trophic biomarkers’: evidence and significance of consumer modification of dietary fatty acids’.


2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Koju Bedekach Bayba ◽  
Amare Aregahegn Dubale ◽  
Bewketu Mehari ◽  
Minaleshewa Atlabachew

Leaf samples of Urtica simensis collected from different locations of Ethiopia were analyzed for their proximate compositions, total phenolic and flavonoid contents, antioxidant activities, and fatty acid profiles. The proximate analysis results revealed the presence of ash in the range 17.2–24.3%, crude fat 3.19–3.50%, crude protein 3.42–6.38%, crude fiber 9.37–14.0%, and carbohydrate 56.7–63.7%. The determined total polyphenols, flavonoids, and antioxidant activities ranged 2.18–4.84 mg gallic acid, 1.35–4.46 mg catechin, and 1.58–3.36 mg ascorbic acid, respectively, equivalents per gram of dry sample. High variability was observed for polyphenol and flavonoid contents while only random variation was observed for crude fat and carbohydrate among samples from different locations. In addition, the fatty acid profiles of the leaves were analyzed by using gas chromatography coupled with mass spectrometry. A total of 16 different fatty acids were detected in the samples. Linolenic, palmitic, and linoleic acids were the major fatty acids with average compositions of 36.6, 20.7, and 15.5%, respectively, of the total fatty acid. The result of this study revealed that the carbohydrate and ash contents of leaves of Urtica simensis are exceptionally high to make the leaves a significant source of the dietary important chemicals. Additionally, the lipid fraction of the leaves was found to be rich in essential fatty acids (α-linolenic and linoleic acids) that are critically required in the human diet.


1969 ◽  
Vol 23 (2) ◽  
pp. 421-427 ◽  
Author(s):  
G. A. Garton ◽  
W. R. H. Duncan

1. Samples of subcutaneous (inguinal) and perinephric adipose tissue were obtained, at slaughter, from each of twenty male calves. Three were neonatal animals, three were 3 days old and two were fed on reconstituted milk to appetite until they weighed 100 kg. The other twelve calves were given milk until they reached 50 kg live weight; concentrates were then included in the diet until, at 60 kg live weight, six calves were slaughtered. The remaining six calves were raised to 100 kg on concentrates alone. The weight of the empty reticulo-rumen of each slaughtered calf was recorded.2. The component fatty acids of the adipose tissue triglycerides of the neonatal and 3-day-old calves were very similar; about 80% consisted of oleic acid (18:1) and palmitic acid (16:0) and the remainder comprised stearic acid (18:0), palmitoleic acid (16:1) and myristic acid (14:0), together with very small amounts of other acids which, in the glycerides of the 3-day-old calves, included some evidently of colostral origin. The perinephric glycerides of both these groups of calves were somewhat more unsaturated than were those of subcutaneous adipose tissue.3. The continued consumption of milk by the calves slaughtered at 60 kg live weight was reflected in the presence of enhanced proportions of 14:0, 18:2, 17:0 and 17:1 in the depot triglycerides and, in addition, very small amounts of branched-chain acids and trans 18:1 were detected. A similar fatty acid pattern was observed in the triglycerides of the calves which were given milk only until they were 100 kg live weight. In all these calves only limited growth of the rumen took place.4. By contrast, the calves which were raised on solid feed from 60 kg to 100 kg and in which rumen development had taken place had depot triglycerides whose fatty acid composition resembled that found in adult animals. Increased proportions of stearic acid accompanied by relatively large amounts of trans 18:1 were present, evidently as a result of the assimilation of the products of bacterial modification of dietary fatty acids in the rumen.5. Regardless of the age of the calves and the over-all fatty acid composition of their tissue triglycerides, the intramolecular disposition of the fatty acids was similar in that saturated components were present esterified mainly in positions 1 and 3, and unsaturated acids for the most part in position 2; the only major exception to this distribution pattern was in respect of trans 18:1 which, when present, was preferentially esterified to the primary alcoholic groups of the glycerol moiety as if it were a saturated acid.


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