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ABSTRACT: The hypothesis tested was that the feeding of n-6 polyunsaturated fatty acids (PUFA) results in more whole-body fatty acid oxidation than the feeding of saturated fatty acids (SFA). It was reasoned that the increased fatty acid oxidation would be associated with enhanced whole-body energy expenditure and stimulated de novo fatty acid synthesis. To put the hypothesis to the test, broiler chickens were fed diets containing either beef tallow as source of SFA or an oil blend as source of n-6 PUFA. The broilers either had free access to their diet or were fed a restricted amount. Seven-day-old, male broiler chickens were used; they were kept individually in cages from 1 to 4 weeks of age. In the birds fed ad libitum, the n-6 PUFA diet reduced average daily feed intake (ADFI), but did not significantly affect average daily weight gain (ADG) and the feed:conversion ratio (FCR). The lower ADFI on the n-6 PUFA diet was associated with a higher apparent digestibility of total fatty acids. The ratio of deposition in the body to intake of digestible total PUFA, which reflected n-6 PUFA, was significantly decreased by the n-6 PUFA diet, pointing at preferentially increased n-6 PUFA oxidation on the n-6 PUFA diet. The ratio for n-9 monounsaturated fatty acids (MUFA) was higher than 1.0, which agrees with net de novo synthesis, but the n-6 PUFA diet induced a lower value than did the SFA diet. Feeding either the n-6 PUFA or SFA diet did not influence energy expenditure expressed as percentage of energy intake. This study supports the idea that dietary n-6 PUFA instead of SFA are preferentially oxidized, but no proof was obtained for enhanced energy expenditure and contrary to the hypothesis put forward, the n-6 PUFA diet depressed de-novo fatty acid synthesis.
J Anim Physiol a Anim Nutr 04/2011; 95(2):228-35. · 0.86 Impact Factor
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ABSTRACT: Isoenergetic substitution of dietary corn oil for dietary carbohydrates enhances growth in rabbits. It was hypothesized that identical amounts of metabolizable energy in the form of corn oil are more effective than those of carbohydrates in reducing protein catabolism and thus sparing it for growth, which would imply that the fat effect is greater on a marginal than normal protein diet. Young growing rabbits were fed semi-purified diets either relatively high (21.6 energy % protein) or low in casein (13.0 energy % protein) to which extra corn oil (21.1 instead of 5.3 energy %) was added at the expense of an isoenergetic amount of corn starch and dextrose. The addition of corn oil to the diet with 21.6 energy % protein indeed increased weight gain, but the addition to the diet with 13.0 energy % protein left weight gain unchanged. These results refute our hypothesis, because the low-protein intake was not limiting growth. The enrichment of the high-protein diet with extra corn oil did not affect nitrogen retention, whereas urinary nitrogen excretion was increased. These observations also are at variance with the idea that additional fat would spare nitrogen for growth.
J Anim Physiol a Anim Nutr 04/2011; 95(2):223-7. · 0.86 Impact Factor
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ABSTRACT: Problem statement: Based on earlier studies in veal calves and rats, the hypothesis tested was that high calcium intakes by ruminating dairy calves reduce fat digestibility, but do not affect growth performance due to enhanced colonization of the intestine with lactobacilli. Approach: In dairy calves that were fed on a combination of milk replacer, concentrate on grass hay, the effects of supplemental calcium on growth, nutrient digestibility and fecal lactobacilli were studied. Four concentrates with different levels of calcium were used. Results: Final body weight and weight gain were raised by the calcium level in the concentrate in a dose-dependent, linear fashion. Apparent digestibility of dry matter, organic matter, crude protein and crude fat were not influenced by the level of calcium in the concentrate. The number of fecal lactobacilli was significantly increased by higher dietary calcium levels, the effect having a linear trend. Calcium intake did not change the number of fecal E. coli . The apparent absorptions of calcium, phosphorus and magnesium were lowered in a linear, dose-dependent fashion by the calcium level in the concentrate. Conclusion: Increased calcium intakes stimulate weight gain in dairy calves fed a combination of milk replacer, concentrate and grass hay. This calcium effect may be related to an enhanced colonization of the intestine with lactobacilli.
American Journal of Animal and Veterinary Sciences. 01/2010;
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ABSTRACT: Problem statement: Different methods of experimental infection of broiler chickens with Eimeria species have been described in the literature. These methods had not been compared and contrasted so as to contribute to the selection of the most appropriate model of coccidiosis in broiler chickens. Identifying such a model was important to speed up the screening of potential coccidiostatics. Approach: In five different experiments with broiler chickens, we used different methods of infection with Eimeria species. In this paper the different methods and the results have been evaluated. Results: Administration through gavage into the crop of relatively low doses of either Eimeria tenella alone, or in combination with Eimeria acervulina and Eimeria maxima , did not influence body-weight gain and feed intake, but did induce intestinal lesions and faecal shedding of oocysts. The administration of an identically high number of sporulated oocysts in the form of a mixture of the three Eimeria species, either through a single dose by gavage or through the litter, produced similar lowering effects on body-weight gain or feed intake, similar degrees of severity of intestinal lesions and similar rates of faecal oocyst shedding. Conclusion: Depending on the variables considered of interest, the present data may indicate the most appropriate model. The model using infection with oocysts through the litter may optimally mimic the field situation in combination with controlled conditions and allowing experimental flexibility and a high number of experimental units within the research facility.
American Journal of Animal and Veterinary Sciences. 01/2010;
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ABSTRACT: Problem statement: Literature data on the effect of dietary fat on growth performance in rabbits are inconclusive. For commercial rabbit production it is relevant to know to what extent dietary fat level and type can be manipulated. In the present study serum cholesterol was also analyzed because its relation to the amount and type of dietary fat was not known for rabbits. Approach: Young growing rabbits were fed diets containing one of four different levels (5.2-41.8 energy %) of either coconut fat or corn oil. Fat was added to the diets at the expense of an isoenergetic amount of corn starch and dextrose in a 1:1 ratio. The diets were in pelleted form and supplied ad libitum . Results: Increasing fat intakes in the form of either coconut fat or corn oil enhanced weight gain and improved feed efficiency. The effect of coconut fat was maximal at 20.9 energy % (9.9%, w/w) and the greatest effect of corn oil was seen at an inclusion level of 41.8 energy % (20.2%, w/w). As would be expected, replacement of dietary corn oil by coconut fat significantly decreased serum cholesterol concentrations. The cholesterol-lowering effect of corn oil versus coconut fat increased markedly with higher dietary inclusion levels of fat. Conclusion: The addition of fat to the diet improved growth performance. It is suggested to find out whether the present observations can be applied in the formulation of diets for fryer rabbits. The new observation for rabbits is that the hypocholesterolemic response to corn oil increased with higher intake levels.
American Journal of Animal and Veterinary Sciences. 01/2010;
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ABSTRACT: Problem statement: In a previous study, the exposure of broiler chickens to a weak Electromagnetic Field (EMF) reduced the severity of a coccidiosis infection. The birds were infected by gavage into the crop which was not representative for the field situation. Approach: The possible anticoccidial activity of EMF was investigated in broiler chickens with a simulated, commercial coccidiosis infection. There was an uninfected and infected group not receiving further treatment. Another uninfected and infected group were subjected to EMF treatment. The infection was induced by adding to the litter a mixture of E. acervulina , E. maxima and E. tenella . EMF treatment lasted for 30 min day<SUP>-1</SUP>; the field strength within the cages was set to 5 μTesla rms. Results: Infection with Eimeria resulted in a transient reduction of growth performance in the control chickens. Exposure to EMF counteracted the effect of infection on growth performance. EMF treatment had no effect on oocyst shedding. In the infected birds exposed to EMF, the lesion scores related to the three Eimeria species were generally lower than in the infected controls. Due to cross-contamination, the uninfected birds also showed intestinal lesions, the severity being less than in the infected chickens. In the uninfected birds, EMF treatment also had reduced the severity of the lesions. Conclusion: In this study EMF exposure protected against coccidiosis in broiler chickens. Consequently, EMF was considered as a possible alternative to anticoccidial drugs.
American Journal of Animal and Veterinary Sciences. 01/2010;
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H. E. Mohamed
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ABSTRACT: The present study was conducted to examine urinary and plasma purine derivatives in light to different feeding protocol; to assess tissue xanthine oxidase activity in plasma, liver and intestine in relation to breed. Breed-related differences in tissue xanthine were observed. Arabi camels have higher figures compared to Anafi. Xanthine oxidase activities in Arabi plasma, liver and intestine were 0.9±0.1, 0.18±0.09 and 0.10±0.03, whereas in Anafi were 0.4±0.09 unit/L, 0.06±0.01 unit/gram wet tissue, 0.09±0.02 unit/gram wet tissue, respectively. Total urinary purine derivatives as a function of feed intake (11.43 vs. 15.09 mmol/d). Allantoin and uric acid compared 75.6 and 15.4% of total purine derivatives, in both fed and fasted camels, but hypoxanthine plus xanthine was 9%.
Journal of Animal and Veterinary Advances. 01/2006;
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H.E. Mohamed
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ABSTRACT: The aim of this study was to establish reference range for folate and vitamin B12 plasma levels in camels (Camelus dromedarius). No effect of sex on folate and vitamin B12 were observed. Folate levels were 9.9 ± 1.9 and 8.3 ± 1.4 μmol L 1 and B12 levels were 169 ± 11.8 and 173 ± 12.4 pmol L 1 for male and females, respectively. As for age, adult camels have significantly higher folate (9.4 ± 1.19 μmol L 1) and B12 (182 ± 13.8 pmol L 1) than yearling (8.7 ± 2.02 μmol L 1), (174 ± 9.11) and neonate (6.8 ± 1.00 μmol L 1), (166 ± 10.9 pmol L 1). Physiological status showed insignificant effect on folate and B12 plasma levels. Folate plasma levels in non-pregnant, pregnant and lactating were 7.9 ± 1.4; 8.2 ± 1.99 and 8.9 ± 2.01 μmol L 1, respectively. However, the corresponding levels for B12 were 177 ± 16.7; 182 ± 13.8 and 185 ±12.1 pmol L 1, respectively.
Journal of Animal and Veterinary Advances. 01/2006;
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H.E. Mohamed
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ABSTRACT: The objective of the present investigation was to evaluate the concentrations of cortisol in peripheral circulation around parturition and weaning in camels (Camelus dromedarius). Ten pregnant Arabi camels, of a mean age of 8.5 years and at 12 months of pregnancy were kept into shaded areas throughout the experimental period (45 days). Sampling intervals were 1 week before parturition, parturition, 1, 3, and 5 days post parturition. No effect of sex on cortisol plasma level was observed. Cortisol level was 121.6 ± 5.4 at day of parturition, and then decreased to 30.1 ± 1.9 and 21.9 ± 1.0ng/ml at day 3 and 5 post parturition, respectively. Cortisol serum level was 37.1 ± 1.4 ng/ml one day before weaning and then increased to 48.0 ±1.5 and 69.5 ± 1.9 ng/ml at weaning and 3rd day after weaning, respectively. The study revealed that following weaning and around parturition, cortisol status increased, which is regarded as an adaptive measure to harsh desert conditions.
Journal of Animal and Veterinary Advances. 01/2006;
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H. E. Mohamed
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ABSTRACT: The study was designed to investigate the effect of age, breed, sex, and breeding season on thiamine and ascorbic acid status (AA) in camels (Camelus dromedarius). A total of 375 camels were sampled over a one-year field survey in Butana area, Central Sudan. No effect of sex on thiamine and ascorbic acid levels was observed. The breeding male and female camels showed higher status of plasma thiamine and lower ascorbic acid as compared to non-breeding camels. Thiamine plasma contents showed variation with respect to age. The thiamine plasma levels for neonate, yearling, and adult were 59.9±4.4, 70.5±8.9 and 88.9±6.7 μg/L, respectively. The corresponding figures for AA were 6.2±1.0, 4.9±0.9, and 4.5±0.8 mg/L, respectively. The Arabi showed higher ascorbic acid (5.9±1.0) than Anafi (4.2±0.9 mg/L). However, no significant breed variation for thiamine status was indicated.
Journal of Animal and Veterinary Advances. 01/2006;
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ABSTRACT: The present study in Sudanese camels was done to describe the associations between vitamin C concentrations in milk, and either breed, stage of lactation, parity or the presence of mastitis. A total of 2586 camels were sampled. Arabi camels had higher ascorbic acid levels in milk than did either Anafi or Bishari camels. Milk ascorbic acid levels were higher for camels more than 180 days in lactation than for those earlier in lactation. Multiparous vs. primiparous camels had higher ascorbic acid concentrations in their milk. The ascorbic acid content of colostrum was higher than that of milk. Mastitis was associated with a decrease in the ascorbic acid content of both milk and blood plasma.
J Anim Physiol a Anim Nutr 03/2005; 89(1-2):35-7. · 0.86 Impact Factor
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H E Mohamed
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ABSTRACT: A study was undertaken to investigate the variations in the content of zinc and copper in the plasma of Sudanese camels (Camelus dromedarius). A total of 993 Arabi camels, aged 0.5-8 years, were used to assess the effect of season, age, sex and physiological status on the plasma concentrations of copper and zinc. There was an increase in the concentration of Cu and a decrease in the concentration of Zn in the plasma with age. The concentrations of both Cu and Zn in the plasma were higher in the rainy season than in the dry season. The plasma copper concentrations in pregnant, low-lactating and high-lactating camels were 81.3 +/- 4.7, 59.7 +/- 6.1 and 61.3 +/- 5.5 microg/100 ml, respectively. The corresponding values for zinc were 51.0 +/- 8.9, 53.4 +/- 6.4 and 67.1 +/- 5.5 microg/100 ml, respectively. However, there was no effect of sex on the content of these minerals in the plasma.
Veterinary Research Communications 08/2004; 28(5):359-63. · 0.82 Impact Factor
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H.E. Mohamed
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ABSTRACT: A study was undertaken to investigate the variations in the content of zinc and copper in the plasma of Sudanese camels (Camelus dromedarius). A total of 993 Arabi camels, aged 0.5–8 years, were used to assess the effect of season, age, sex and physiological status on the plasma concentrations of copper and zinc. There was an increase in the concentration of Cu and a decrease in the concentration of Zn in the plasma with age. The concentrations of both Cu and Zn in the plasma were higher in the rainy season than in the dry season. The plasma copper concentrations in pregnant, low-lactating and high-lactating camels were 81.34.7, 59.76.1 and 61.35.5 g/100 ml, respectively. The corresponding values for zinc were 51.08.9, 53.46.4 and 67.15.5 g/100 ml, respectively. However, there was no effect of sex on the content of these minerals in the plasma.
Veterinary Research Communications 06/2004; 28(5):359-363. · 0.82 Impact Factor
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ABSTRACT: Healthy camels (Camelus dromedaris) and those naturally infected with trypanosomiasis, sarcoptic mange, and helminthiasis were compared as to ascorbic acid (vitamin C) contents of red blood cells, white blood cells, whole blood, plasma, and liver. The camels were kept under natural grazing conditions in Sudan. Reduced levels of vitamin C were found in camels with parasite infections, especially in animals with trypanosomiasis. It is suggested that the low vitamin C status in infected camels is caused by increased utilization and/or decreased synthesis of vitamin C.
International Journal for Vitamin and Nutrition Research 01/2003; 72(6):369-71. · 0.88 Impact Factor
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ABSTRACT: There is suggestive evidence that a low status of ascorbic acid in ruminants is related with decreased disease resistance. In a first attempt to identify conditions in camels that could affect their health, an inventory was made of ascorbic acid (vitamin C) concentrations in plasma and tissues as related to breed, gender, sexual activity and season. A total of 3429 camels were studied and sub-samples were used for selected comparisons. The highest concentrations of ascorbic acid were found in adrenals (152 mg/100 g wet tissue) and the lowest in heart (8 mg/100 g), the levels being unrelated with season. Arabi camels had higher plasma concentrations of ascorbic acid (6.42 microg/ml) than did Anafi and Bishari camels, the latter breed showing the lowest concentrations (3.24 microg/ml). Female camels of the Anafi breed had higher concentrations urinary ascorbic acid than did their male counterparts. It is suggested that in camels the main elimination route of vitamin C is with urine. Female and male Arabi camels that were sexually active had 52 and 23% lower plasma ascorbic acid concentrations than did their sexually inactive counterparts. It is suggested that especially Bishari camels during the breeding season might be sensitive to disease.
J Anim Physiol a Anim Nutr 11/2002; 86(9-10):342-6. · 0.86 Impact Factor
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ABSTRACT: Interferon alpha (IFN-alpha) inhibits insulin release and may be cytotoxic to pancreatic islets. Increased free radical activity may be implicated in the cytotoxic action of IFN-alpha and development of diabetes mellitus. Therefore we measured markers of free radical activity (lipid peroxides and the non-peroxide-conjugated diene isomer of linoleic acid [PL-9,11-LA']) along with some pancreatic variables in male albino rats treated with IFN-alpha, as well as the possible protective effect of two antioxidants, vitamin C and mannitol. Compared to untreated rats, it was shown that IFN-alpha induced an increase in plasma glucose. Pancreatic and serum insulin, as well as serum C-peptide, were increased after 1 week, then their levels were reduced after 2 weeks. Plasma lipids peroxides and (PL-9,11-LA') were markedly elevated, while linoleic acid was reduced. These changes in the studied parameters were attributed, in part, to the superoxide and free radical generation during IFN-alpha treatment. Plasma glucagon was increased after 2 weeks. Administration of vitamin C along with IFN-alpha succeeded in modulating most of the altered parameters affected during IFN-alpha. The hyperglycaemic effect of IFN-alpha was greatly ameliorated and the negative effect on pancreatic and serum insulin and serum C-peptide were nearly abolished. The elevated levels of lipid peroxide and (PL-9,11-LA') and the reduction in linoleic acid being normalised. The only persistent effect was the increase in plasma glucagon. Concurrent administration of mannitol with IFN-alpha caused no changes in the parameters studied compared to that induced by treatment with IFN-alpha alone.
Pharmacological Research 08/1998; 38(1):59-64. · 4.44 Impact Factor
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