RESUMO
One of the main challenges in the livestock sector is the need to increase sustainability and production efficiency. In pig production, feed is the main production cost. High moisture grains (HMGs) have recently emerged as an interesting alternative to conventional feedstuffs. In this study, the nutritional value for pigs of eight HMGs was determined considering the chemical composition and the in vitro digestibility. We have used four seeds (lupine, barley, wheat, and corn) and two substrates (water and whey). Lupine HMG showed higher values of crude fat (2.12%) and crude protein (8.59%). Within cereal HMGs, corn HMG showed higher DM (34.37%), OM (36.27%), and starch (27.17%) values; wheat HMG stood out for crude protein content (4.23%) and barley for NDF (5.68%). The pH values were low for all HMG, with lupine having the highest value (4.39). Ammoniacal nitrogen had the highest value for wheat HMG (6.10%). When whey was used as substrate, it improved the characteristics of the HMG. Regarding in vitro digestibility, of the four HMGs studied, wheat showed the highest value for DM (89.93%), while lupine showed the highest value for crude protein (96.12%). When considering the substrates, whey showed better results for all in vitro digestibility's parameters (87.48%, 90.95%, and 90.59%, for DM, OM, and crude protein, respectively). Overall, all HMGs showed good conservation of nutritional value and high in vitro digestibility. The use of whey as a substrate was beneficial for HMG quality. Results show that the analyzed HMG can be efficiently used in the framework of swine production.
Assuntos
Ração Animal , Hordeum , Ração Animal/análise , Animais , Digestão , Grão Comestível/química , Suínos , Triticum/metabolismoRESUMO
The aim of this study was to assess the nutritional effect of tomato pomace, in combination with two distinct fat sources (lard or soya bean oil), on longissimus lumborum muscle, subcutaneous fat and liver of young pigs. Forty male pigs of 4 weeks old were randomly assigned to four dietary treatments using two fibre sources (wheat bran or 5.0% tomato pomace) and two fat sources (lard or soya bean oil), in a 2 × 2 factorial design for a 5-week trial. Tomato pomace did not improve colour, fatty acid profile, cholesterol content or lipid oxidation, nor did it yield detectable levels in lycopene or ß-carotene in the meat (p > 0.05). However, a positive increase in α-tocopherol content of meat and liver was observed in pigs fed tomato pomace (p < 0.05). Compared with lard, soya bean oil increased MUFA and PUFA proportions and decreased the percentage of SFA (p < 0.05). Our results indicate that 5.0% of tomato pomace increases pork oxidative stability and that 5.0% of soya bean oil, compared with lard, improves its nutritional quality.
Assuntos
Ração Animal/análise , Dieta/veterinária , Carne/análise , Solanum lycopersicum , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ácidos Graxos/química , Peroxidação de Lipídeos , Oxirredução , Suínos/fisiologiaRESUMO
Laminaria digitata is a brown seaweed rich in prebiotic polysaccharides, mainly laminarin, but its alginate-rich cell wall could compromise nutrient access. Carbohydrase supplementation, such as individual alginate lyase and carbohydrases mixture (Rovabio® Excel AP), could enhance nutrient digestibility and prebiotic potential. This study aimed to evaluate the effect of these enzymes on nutrient digestibility and gut health of weaned piglets fed with 10% L. digitata. Diets did not affect growth performance (P > 0.05). The majority of the feed fractions had similar digestibility across all diets, but the supplementation of alginate lyase increased hemicellulose digestibility by 3.3% compared to the control group (P = 0.047). Additionally, we observed that algal zinc was more readily available compared to the control group, even without enzymatic supplementation (P < 0.001). However, the increased digestibility of some minerals, such as potassium, raises concerns about potential mineral imbalance. Seaweed groups had a higher abundance of beneficial bacteria in colon contents, such as Prevotella, Oscillospira and Catenisphaera. Furthermore, the addition of alginate lyase led to a lower pH in the colon (P < 0.001) and caecum (P < 0.001) of piglets, which is possibly a result of released fermentable laminarin, and is consistent with the higher proportion of butyric acid found in these intestinal compartments. L. digitata is a putative supplement to enhance piglet gut health due to its prebiotic polysaccharides. Alginate lyase supplementation further improves nutrient digestibility and prebiotic potential. These results suggest the potential use of L. digitata and these enzymatic supplements in commercial piglet-feeding practices.
Assuntos
Ração Animal , Suplementos Nutricionais , Digestão , Glicosídeo Hidrolases , Polissacarídeo-Liases , Animais , Masculino , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão/efeitos dos fármacos , Algas Comestíveis , Microbioma Gastrointestinal/efeitos dos fármacos , Glicosídeo Hidrolases/metabolismo , Laminaria/química , Nutrientes/metabolismo , Polissacarídeo-Liases/metabolismo , Prebióticos , Suínos , DesmameRESUMO
1. Microbial ß-1,3-1,4-glucanases improve the nutritive value of barley-based diets for poultry by effectively decreasing the degree of polymerisation of the anti-nutritive soluble ß-glucans. Glycoside hydrolases (GHs) acting on recalcitrant polysaccharides display a modular architecture comprising a catalytic domain linked to one or more non-catalytic Carbohydrate-Binding Modules (CBMs). 2. GHs and CBMs have been classified in different families based on primary structure similarity (see CAZy webpage at http://www.cazy.org ). The role of CBMs is to anchor the appended GHs into their target substrates, therefore eliciting the efficient hydrolysis of structural carbohydrates. 3. Here we describe the biochemical properties of the family 16 GH from Clostridium thermocellum, termed CtGlc16A. CtGlc16A is a thermostable enzyme that specifically acts on ß-1,3-1,4-glucans with a remarkable catalytic activity (38000 U/mg protein). 4. CtGlc16A, individually or fused to the family 11 ß-glucan-binding domain of cellulase CtLic26A-Cel5E of C. thermocellum, was used to supplement a highly viscous barley-based diet for broilers. 5. The data showed that birds fed on diets supplemented with the recombinant enzymes displayed an improved performance when compared with birds given diets not supplemented with exogenous enzymes. However, inclusion of the non-catalytic CBMs had no influence on the capacity of CtGlc16A to reduce the anti-nutritive effects of soluble ß-1,3-1,4-glucans. 6. The data suggest that at elevated dosage rates, CBMs might be unable to potentiate the catalytic activity of appended catalytic domains; this effect may only be revealed when feed enzymes are incorporated at low levels.
Assuntos
Galinhas/fisiologia , Clostridium thermocellum/enzimologia , Dieta/veterinária , Glicosídeo Hidrolases/administração & dosagem , Hordeum , Valor Nutritivo , Animais , Celulase/administração & dosagem , Celulase/genética , Clonagem Molecular , Suplementos Nutricionais , Estabilidade Enzimática , Expressão Gênica , Glicosídeo Hidrolases/genética , Temperatura Alta , Proteínas Recombinantes de Fusão/administração & dosagemRESUMO
To improve the nutritive value of barley-based diet for broilers, 2 experiments using 2 different barley lots were performed to evaluate the capacity of a mesophilic cellulase when fused to a ß-glucan specific family 11 carbohydrate-binding module. The data revealed that the recombinant ß-glucanase derivatives were not appropriate for feed supplementation because of a lack of stability at acidic pH levels. However, under the same experimental conditions, a commercial enzyme mixture improved the nutritive value of 1 of the cereal lots used. Analysis of the nutritive value of the 2 barleys revealed intrinsic differences in the levels of endogenous ß-glucanase activity. These differences were extensively evident when the studies were expanded to a range of 64 barley lots. Thus, to clarify the effect of endogenous cellulases on the efficacy of exogenous ß-glucanases used to supplement barley-based diets for poultry, 2 barley lots presenting low and high levels of endogenous plant cell wall-degrading enzymes were selected. These lots were used to prepare 2 barley-based diets, which were supplemented with or without a commercial enzyme product and fed to broiler chicks. The data revealed that the exogenous enzymes were effective when the basal diet presented low levels of endogenous ß-glucanases but were unable to improve the nutritive value of the barley lot displaying higher ß-glucanase activity. Thus, these studies suggest that levels of endogenous ß-glucanases may affect the efficacy of exogenous enzymes used to improve the nutritive value of barley-based diets for broilers. The development of a quick ß-glucanase assay that could be applied for cereal-based feeds may help identify those barley-based diets that are more responsive to the action of feed enzymes.
Assuntos
Ração Animal/análise , Celulase/farmacologia , Dieta/veterinária , Glicosídeo Hidrolases/metabolismo , Hordeum/enzimologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Glucanos/metabolismo , Valor Nutritivo , Proteínas RecombinantesRESUMO
1. Exogenous microbial beta-1,3-1,4-glucanases and hemicellulases contribute to improving the nutritive value of cereals rich in soluble non-starch polysaccharides for poultry. 2. In general, plant cell wall hydrolases display a modular structure comprising a catalytic module linked to one or more non-catalytic carbohydrate-binding modules (CBMs). Based on primary structure similarity, CBMs have been classified in 50 different families. CBMs anchor cellulases and hemicellulases into their target substrates, therefore eliciting efficient hydrolysis of recalcitrant polysaccharides. 3. A study was undertaken to investigate the effects of a family 11 beta-glucan-binding domain in the function of recombinant derivatives of cellulase CtLic26A-Cel5E of Clostridium thermocellum that were used to supplement a barley-based diet at lower dosage rates. 4. The results showed that birds fed on diets supplemented with the recombinant CtLic26A-Cel5E modular derivative containing the family 11 CBM or the commercial enzyme mixture Rovabio Excel AP tended to display improved performance when compared to birds fed diets not supplemented with exogenous enzymes. 5. It is suggested that at lower than previously reported enzyme dosage (10 U/kg vs 30 U/kg of basal diet), the beta-glucan-binding domain also elicits the function of the recombinant CtLic26A-Cel5E derivatives. 6. Finally, the data suggest that exogenous enzymes added to barley-based diets act primarily in the proximal section of the gastrointestinal tract.
Assuntos
Celulase/farmacologia , Galinhas/metabolismo , Dieta/veterinária , Hordeum , Receptores de Superfície Celular/metabolismo , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Celulase/administração & dosagem , Relação Dose-Resposta a Droga , Complexos Multienzimáticos/administração & dosagem , Receptores de Superfície Celular/administração & dosagem , Proteínas Recombinantes , Aumento de PesoRESUMO
1. Cellulases and xylanases display a modular architecture that comprises a catalytic module linked to one or more non-catalytic carbohydrate-binding modules (CBMs). CBMs have been classified into 52 different families, based on primary structure similarity. These non-catalytic modules mediate a prolonged and intimate contact of the enzyme with the target substrate eliciting efficient hydrolysis of the target polysaccharides. 2. A study was undertaken to investigate the importance of a family 11 CBM, displaying high affinities for barley beta-glucans, in the function of recombinant derivatives of cellulase CtLic26A-Cel5E of Clostridium thermocellum used to supplement a barley-based diet for broiler chicken. 3. The results showed that birds fed on diets containing the recombinant CtLic26A-Cel5E modular derivatives or the commercial enzyme mixture Rovabio Excel AP displayed improved performance when compared with birds fed on diets not supplemented with exogenous enzymes. 4. It is suggested that the enzyme dosage used in this study (30 U/kg of basal diet), was probably too high for the efficacy of the family 11 CBM to be noticed. It remains to be established if the targeting effect resulting from the incorporation of CBMs in plant cell wall hydrolases may be effective at lower exogenous enzyme dosages.
Assuntos
Celulases/metabolismo , Galinhas/fisiologia , Dieta/veterinária , Hordeum , Receptores de Superfície Celular/metabolismo , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Celulases/química , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Comportamento Alimentar , Receptores de Superfície Celular/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Aumento de PesoRESUMO
A permanent supraventricular tachycardia (SVT) was diagnosed in a 54-year-old hypertensive but cardiologically asymptomatic female patient, admitted to a surgery department for biliary lithiasis and hepatic echinococcosis. Heart rate was about 130 bpm and ECGs showed negative P waves in leads I, II, III, aVF, and precordial leads V2 to V6, being the RP' interval longer than P'R interval. Pharmacological intervention during Holter monitoring (20 hours) was instituted: following i.v. propranolol (4 mg), heart rate progressively decreased (to 112 bpm), mainly due to an increase in SVT RP' interval, and brief, spontaneous SVT interruptions occurred, preceded by P'R interval prolongation; SVT stopped after P' recording, and resumed after 2 sinus beats, (showing enlarged P waves and slightly prolonged PR interval), induced by cycle length shortening; later on, under i.v. amiodarone infusion (100 mg/hour) and coincident with the sleeping period, SVT cycle length progressively increased (to 600 msec), due to equivalent increases in P'R and R'P intervals. Two premature ventricular contractions (PVC) occurred during Holter monitoring at a coupling interval of 80-85% of SVT cycle length (480 msec): one PVC apparently originated in left ventricle lateral wall, captured the atria, which were activated 75 msec earlier than expected; the other PVC, apparently originated in left ventricle septoapical region, did not interfere with SVT cycle length. Before these data, a diagnosis of circus movement tachycardia, incorporating a concealed accessory pathway with slow retrograde conduction and ventricular insertion in the postoroseptal or left posterior paraseptal region, and showing minor impairment of antegrade AV nodal conduction, was made. Invasive electrophysiological study was then discarded. With combined oral antiarrhythmic therapy (amiodarone, 600 mg/d), plus propafenone, 450 mg/d), sinus rhythm was permanently restored, with evidence of intraatrial block, slightly prolonged PR interval and no preexcitation. Transesophageal echocardiography revealed a small atrial septal aneurysm associated with a small atrial septal defect; echocardiographic features were consistent with the hypothesis of incomplete regression of the atrial septal aneurysm after partial closure of the atrial septal defect. Abdominal surgery (cholecystectomy plus partial hepatic pericystectomy) was performed without any complications or SVT recurrences. During a 6-month follow-up period, maintaining amiodarone (200 mg/d) and propafenone (450 mg/d), the patient remained SVT-free, and Holter monitoring performed at 3 and 5 months showed permanent sinus rhythm and 1:1 AV conduction with slightly prolonged PR interval (less than 0.29 sec and shortening at faster heart rates). This case documents Holter monitoring capability for the evaluation of tachycardia mechanisms in patients with permanent SVT.
Assuntos
Eletrocardiografia , Aneurisma Cardíaco/complicações , Septos Cardíacos , Taquicardia Supraventricular/fisiopatologia , Amiodarona/uso terapêutico , Equinococose Hepática/diagnóstico , Equinococose Hepática/cirurgia , Ecocardiografia , Feminino , Seguimentos , Aneurisma Cardíaco/fisiopatologia , Humanos , Pessoa de Meia-Idade , Taquicardia Supraventricular/tratamento farmacológicoRESUMO
Occlusive disease involving the renal arteries represent a major cause of curable hypertension and improvement of renal dysfunction. Angiography is still the major diagnostic procedure. Isotopic methods with Captopril and split-function studies have shown high incidence of false-positive and false-negative results. Colour flow Duplex-Scan renders possible the visualization of the aorta and renal arteries, is noninvasive and combines morphologic and hemodynamic evaluation. To assess its efficacy in the diagnosis of renal artery occlusive disease, a prospective blind study was undertaken in 24 patients, 48 renal arteries, 15 women and 9 men, with mean age of 44 years. Scans of the aorta and renal arteries at the origin, along its extension and at the renal hilum were obtained using and ATL Ultrmark 9 with 3.0 MHZ probe Velocity measurements were obtained at the aorta and along the renal arteries. Criteria for a positive examination were: focal acceleration with a reduction of the flow velocity at the hilum. Absence of flow in a properly visualized renal artery was considered as occlusion. All patients had digital subtraction arteriography. In 1 patient the non-invasive examination was inadequate. In the remain 23 patients the exam was considered adequate. False-positives were 4.8%; false-negatives 8.7%. Sensitivity, specificity and accuracy were respectively 91.7%, and 95.7% and 93.5%. These results suggest that non-invasive assessment of renal artery occlusive disease is feasible and accurate when compared to angiography, thus providing a useful tool for screening hypertensive patients.
Assuntos
Obstrução da Artéria Renal/diagnóstico por imagem , Adolescente , Adulto , Idoso , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , UltrassonografiaRESUMO
Endovascular treatment of aneurysmal disease of descending thoracic aorta and infra-renal abdominal aorta, has become an accepted technique, in selected cases due to the reduction of neurological morbidity, paraparesis or paraplegic and renal ischemia, associated with conventional surgery. The authors describe the first case performed in Portugal of a 75-year-old female with an expanding thoracic aneurysm managed by endovascular exclusion of the aneurysm with an EXCLUDER endoprosthesis, without any complications or evidence of endoleak, achieving complete exclusion of the aneurysm.
Assuntos
Aneurisma da Aorta Torácica/terapia , Dissecção Aórtica/terapia , Stents , Idoso , Dissecção Aórtica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Implante de Prótese Vascular/métodos , Cateterismo Periférico/métodos , Feminino , Humanos , Radiografia Intervencionista , Tomografia Computadorizada por Raios XRESUMO
Failure of the guide-wire to recanalize some arterial total occlusion does not preclude balloon angioplasty. Nowadays there are recanalization devices such as the mechanical atherectomy and Lasers. The following report describes the successful use of the Nd: YG Laser in the recanalization of a common iliac artery total occlusion in a patient with claudication, rendering possible balloon angioplasty and a Palmaz Stent implantation, which is the first case performed in our country.
Assuntos
Arteriopatias Oclusivas/cirurgia , Artéria Ilíaca/cirurgia , Terapia a Laser , Idoso , Humanos , MasculinoRESUMO
Carotid artery surgery became an established procedure for the treatment of cerebrovascular insufficiency associated with carotid artery stenosis and for the prevention of Stroke. 180 patients were consecutively treated because of occlusive disease of the carotid arteries: 152 (84%) had TIA's or reversible deficits, 11 (6.1%) had strokes with partial recovery, 16 (8.8%) asymptomatic carotid disease and 1 patient (0.5%) had global cerebral ischemia. The severity of occlusive disease was assessed by ECHO-DOPPLER, with or without colour mapping and by angiography: 21 had minimal lesions (less than 20%), 58 stenosis between 21-75%, 92 stenosis between 76-99% and 7 had complete occlusion of the carotid artery; 2 patients had aneurysmal disease 196 operations were performed; early mortality (less than 30 days) was 2.2% (4/180) and neurological morbidity 1.6% (3/180), the operative risk being 3.8%. Longterm results were assessed during a follow-up period extending to 132 months and were assessed by life-table analysis. Survival was 52.5%, 79.3% of the patients were fully asymptomatic during the follow-up but 89.2% were stroke-free, the incidence of stroke being 0.97%/year. These results compare favorably with data available from the natural history and confirm the efficacy of carotid artery reconstructive surgery for the prevention of stroke.
Assuntos
Arteriopatias Oclusivas/cirurgia , Isquemia Encefálica/cirurgia , Doenças das Artérias Carótidas/cirurgia , Adulto , Idoso , Arteriopatias Oclusivas/mortalidade , Isquemia Encefálica/mortalidade , Doenças das Artérias Carótidas/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida , Fatores de TempoRESUMO
Cerebrovascular disease is the most important cause of mortality and morbility in some European Countries, but the prevalence of carotid occlusive disease has not been adequately assessed. From 1985 to 1987, 1,143 patients were consecutively evaluated in the Vascular Laboratory in order to determine the presence of extracranial carotid occlusive disease. 638 (55.8%) were males and 505 (44.2%) females and mean age was 58 years (16-87). 509 had previously focal brain ischemia, ocular and/or hemispheric (Group I), 78 had assymptomatic cervical bruit (Group II), 55 non-hemispheric neurologic dysfunction (Group III) and 501 had atypical symptoms for cerebrovascular disease (Group IV). Diagnostic criteria for carotid disease: were peak frequency greater than 4.0 KHz; spectral broadening greater than 40% and late sysstolic turbulence. Global prevalence of carotid disease was 31.8% and the results in each group were: Gr. I-37.2%; Gr. II-57.7%; Gr. III-43.6%; Gr. IV-21.2%. 49% of the patients had hypertension, 22.8% dyslipidemia, 22.4% evidence of coronary disease and 13.6% had diabetes. Hypertension, diabetes, coronary disease and the coexistence of two risk factors were significantly more prevalent in the group of patients with carotid disease. These results confirm a high prevalence of carotid disease in this population, which is comparable to the one is northern european populations.
Assuntos
Arteriopatias Oclusivas/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/epidemiologia , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de RiscoRESUMO
The effects of Ile and Val supplementation of a low-CP, corn-wheat-soybean meal-based piglet diet on growth performance, incidence of diarrhea, and N balance were studied using 60 Landrace x Duroc male piglets in a 4-wk experiment. The 60 individually caged piglets were divided into 5 dietary treatments, each consisting of 12 piglets. Diet 1 was a positive control diet (20% CP); diet 2 was a low-CP negative control diet (17% CP); diets 3, 4, and 5 were low-CP diets to which Ile, Val, or the combination of Ile and Val were added, respectively. All diets were supplemented with Lys, Met, Thr, and Trp to provide the required concentrations of these AA according to the 1998 NRC. Average daily gain and ADFI were similar among pigs fed the positive control, Val-added, and the Val plus Ile-added diets. On wk-2 and wk-4, fecal score was greater (softer feces) in piglets fed the 20% CP level compared with the remaining treatments (P < 0.01). Nitrogen intake was decreased (P < 0.0001) in pigs fed diets containing low levels of CP compared with pigs fed the 20% CP diet. Fecal N excretion (g/d) was decreased (P < 0.05) in piglets fed low-CP diets at wk 1 and wk 4 of feeding, and in urine at wk 4 of feeding. Crude protein levels or AA supplementation had no effect on N retention efficiencies. These results indicate that the supplementation of Val alone, or in combination with Ile, to a low-CP piglet diet with adequate levels of Lys, Met, Thr, and Trp is necessary to achieve maximum performance in pigs consuming corn-wheat-soybean meal-based diets.
Assuntos
Ração Animal , Dieta com Restrição de Proteínas/veterinária , Suplementos Nutricionais , Isoleucina/administração & dosagem , Nitrogênio/metabolismo , Suínos , Valina/administração & dosagem , Animais , Ingestão de Alimentos/fisiologia , Masculino , Distribuição Aleatória , Suínos/crescimento & desenvolvimento , Suínos/metabolismoRESUMO
We present a case of benign acquired tracheo-esophageal fistula caused by cuffed tracheal tube. The patient was septic and weaning from the mechanical ventilation was unlikely, so immediate repair of the tracheal and esophageal lesions was imperative. A silicone endoprosthesis was inserted in the tracheal lumen and the esophageal lesion was repaired with direct suture. After weaning from mechanical ventilation and recovery, the patient was discharged with a silicone tracheal stent. Three months later the stent was removed without complications or need for further treatment. This combined approach as never been published before, and can be a very useful alternative for the treatment of this rare but taxing complication.
Assuntos
Broncoscopia , Intubação Intratraqueal/efeitos adversos , Implantação de Prótese/métodos , Stents , Traqueia/cirurgia , Fístula Traqueoesofágica/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Silicones , Fístula Traqueoesofágica/diagnóstico , Fístula Traqueoesofágica/etiologia , Resultado do Tratamento , Desmame do RespiradorRESUMO
Twenty-four male piglets weaned after 21 days, 12 of the Large White lean breed (LW) and 12 of the Alentejano fat breed (AL), have been used to compare the effects of genotype and source of dietary fat on the activities of enzymes involved in lipogenesis and on the composition of selected fatty tissues. During 4 weeks the piglets were fed isoenergetic and isonitrogenous experimental diets, containing 5 % of either olive oil or tallow. In AL piglets the acetylcoenzyme A carboxylase activity was three- and ninefold higher, the malic enzyme activity six- and fivefold, and the glucose-6-phosphate dehydrogenase activity was four- and fivefold higher in the dorsal subcutaneous and in the perirenal fat, respectively, than in LW piglets. In general, fatty tissues of the AL piglets contained a higher proportion of saturated fatty acids. Olive oil induced a significant increase in the activities of malic enzyme and glucose-6-phosphate dehydrogenase in both tissues, but only slightly increased the acetylcoenzyme A carboxylase activity in perirenal fatty tissues (p < 0.05). The fatty acid profile of the subcutaneous and of the perirenal fat was strongly affected by the composition of dietary fat. These observations showed that the source of dietary fat influenced markedly lipid metabolism and body composition since a very early age.