Comparative analysis of buffalo, local and continental cattle carcasses with the European Union classification system in Greece.

The carcasses produced in Greece from Greek Buffalo, indigenous and local crossbred cattle were evaluated using the European Union (EU) bovine classification system and compared with carcasses of continental breeds reared in the country. The main carcass production (67.8%) came from animals born in Greece with a relatively low percentage from local breeds (17%). The lightest carcass weight was found in Greek Brachyceros [145.2 ± 2.3 kg (males); 146.0 ± 3.1 kg (females)], while among locals the Greek Blonde rendered the heaviest carcass weights [303.2 ± 2.9 kg (males); 265.3 ± 3.5 kg (females)]. Muscle conformation scoring was the lowest in Buffalo [4.1 ± 0.1 (males); 4.9 ± 0.0 (females)] and the highest for males of Charolais and Blonde d'Aquitaine (11.2 ± 0.0 and 10.7 ± 0.0, respectively). The meat-purposed breeds produced carcasses of higher quality than dual-purposed, local breeds and dairy Holstein-Friesian. With the discriminant analysis, the correct classification of carcasses varied from 53.4% (males) to 47.8% (females) with high assignment percentage of Greek Buffalo males (81.6%), Simmental males (80.7%) and Holstein-Friesian females (98.5%).

Effects of caponization on fat metabolism-related biochemical characteristics of broilers.

A two-trial experiment was conducted to evaluate the effects of caponization on fat metabolism-related biochemical characteristics of broilers. Male Redbro broilers were purchased, caponized at 3 weeks and reared until either the 18th (Trial 1) or the 24th (Trial 2) week. In Trial 1, five slaughters were performed at 6, 9, 12, 15 and 18 weeks of age while in Trial 2 one slaughter at the end of the experiment (24 weeks). In each slaughter, the abdominal adipose tissue cellularity, the NADP dehydrogenase activity in the liver and some serum lipoproteins concentrations were assessed. Caponization had a marked effect on the adipocyte volume and NADP-malate dehydrogenase activity in the liver at 24 weeks but it did not affect adipocyte number or the activity of NADP-isocitrate dehydrogenase activity at any age (p < 0.05). Regarding the lipoproteins, cholesterol and HDL-cholesterol were elevated in capon serum at 18 weeks of age while no difference was detected in the triglyceride concentration at any age. In conclusion, a relationship between fat deposition at the phenotypic level and the level of lipogenic enzymes and lipoproteins capons was established but not as pronounced as expected as some parameters displayed a constant increasing pattern while others did not.

Effects of caponization on growth performance, carcass composition and meat quality of males of a layer line.

The present experiment was conducted in order to evaluate the effects of caponization on growth, carcass composition and meat quality of males of a layer line reared until the 34th week of age. Two hundred and fifty males of a layer line were purchased and randomly divided in two equal groups: intact males and capons. Caponization was conducted at 45 days of age. Three slaughters were performed at the ages of 26, 30 and 34 weeks of age. Caponization did not affect feed intake and final live weight. Capons had a heavier breast and lighter leg than intact males. Lipid accumulation was enhanced by the caponization and fat was stored mainly at the fat pad and the skin of the commercial parts excluding the drumstick. The Pectoralis major muscle of capons had higher intramuscular fat content, lightness (L) and yellowness (b*) values and lower redness values (a*). In conclusion, caponization could be applied to a layer genotype in order to produce commercial chicken meat.

Expression of plasminogen activator-related genes in the adipose tissue of lactating dairy sheep in the early post-weaning period.

There is growing evidence that plasminogen activator inhibitor type 1 (PAI-1) is expressed in adipose tissue and its expression is implicated in inflammation that accompanies obesity-associated diseases. The physiological role of other genes implicated in the plasminogen-activating cascade such as urokinase-type plasminogen activator (u-PA), u-PA receptor (u-PAR) and plasminogen activator inhibitor type 2 (PAI-2) in ovine adipose tissue remains unknown. The objective of this study was to examine the changes in the expression of four plasminogen activator (PA)-related genes during the early post-weaning period in dairy ewes. A total of 21 subcutaneous adipose tissue samples were obtained from seven lactating dairy ewes of the Chios breed at weeks 1, 2 and 4 after weaning. Results indicated that expression of all PA-related genes was detected in most of the samples examined. Greatest expression of u-PAR corresponded to highest (week 1), while greatest expression of PAI-2 corresponded to lowest (week 4) rate of lipolysis, as indicated by the expression of hormone-sensitive lipase, in the ovine adipose tissue. There were no significant differences in the expression of the other two PA-related genes (u-PA, PAI-1) throughout the experimental period. Plasminogen activator-related genes are not expressed in a coordinated manner in the adipose tissue of lactating dairy sheep in the early post-weaning period. In conclusion, adipose tissue mobilization is correlated with highest expression of u-PAR and lowest expression of PAI-2.

Effects of caponisation on lipid and fatty acid composition of intramuscular and abdominal fat of medium-growth broilers.

1. Capons and intact male broilers were used to investigate the effects of caponisation on intramuscular fat and abdominal adipose tissue lipid content and fatty acid profile. 2. Capons had significantly higher total lipid content (P<0·05). 3. Neutral lipids were the major fractions in intramuscular and abdominal fat but their proportions differed significantly among groups and tissues (P<0·05). 4. The predominant saturated, monounsaturated and polyunsaturated fatty acids in all samples were C16:0, C16:1 ω-9, C18:0, C18:1 ω-9, C18:1 ω-7, C18:2 ω-6 and C20:4 ω-6. 5. Caponisation resulted in a significant ω-6/ω-3, PUFA and PUFA/SFA ratio reduction as well as a significant increase in atherogenic and thrombogenic indices increase in intramuscular fat (P<0·05) without affecting their appropriate value for a healthy diet.

Comparative Approach of the de novo Fatty Acid Synthesis (Lipogenesis) between Ruminant and Non Ruminant Mammalian Species: From Biochemical Level to the Main Regulatory Lipogenic Genes.

Over the second half of 20(th) century much research on lipogenesis has been conducted, especially focused on increasing the production efficiency and improving the quality of animal derived products. However, many diferences are observed in the physiology of lipogenesis between species. Recently, many studies have also elucidated the involvement of numerous genes in this procedure, highlighting diferences not only at physiology but also at the molecular level. The main scope of this review is to point out the major differences between ruminant and non ruminant species, that are observed in key regulatory genes involved in lipogenesis. Human is used as a central reference and according to the findinggs, main differences are analysed. These findings could serve not only as basis for understanding the main physiology of lipogenesis and further basic research, but also as a basis for any animal scientist to develop new concepts and methods for use in improving animal production and modern genetic improvement.

Effects of caponization on growth performance, carcass composition, and meat quality of medium growth broilers.

A 2-trial experiment was conducted to evaluate the effects of caponization on growth performance, carcass composition, and meat quality of medium growing broilers. Male chicks were caponized at 3 wk of age and reared until either 18 (trial 1) or 24 (trial 2) wk of age. In trial 1, the experimental groups included intact males, sham-operated chickens, and capons, whereas trial 2 comprised only intact males and capons. The concentration of testosterone was drastically reduced by caponization but remained detectable (trial 1). In both trials, BW was lower for capons during 4 to 9 or 10 wk of age when contrasted to intact males (P < 0.05). In trial 1, capons had heavier livers than intact males and sham-operated chickens. In addition, they had lighter hearts than sham-operated chicks (P < 0.05). In trial 2, capons displayed smaller drumstick and heart weights (P < 0.05). There was a tendency for increased fat pad weight in capons (P < 0.10). Caponization resulted in increased skin-fat weights of the thigh and the breast of 24 wk of age. This was also valid for carcass fat, when expressed as a percentage of the cold carcass weight, and intramuscular fat. Caponization had no effect on pH 24 h postmortem and cooking loss. Capons' breasts had lower shear values and displayed lighter, more yellow, and less red meat than that of intact males. Conclusively, caponization, without affecting growth performance, altered meat quality characteristics, resulting in special quality chicken meat.

The effect of various vitamin E derivatives on the urokinase-plasminogen activator system of ovine macrophages and neutrophils.

The effect of vitamin E derivatives on the urokinase-plasminogen activator (u-PA) system of resting and phorbol myristate acetate (PMA)-activated ovine macrophages and neutrophils were investigated. Blood monocyte-macrophages and neutrophils were isolated from twenty-four animals. Macrophages or neutrophils were cultured in vitro for 3 or 24 h with or without various vitamin E derivatives: free alpha-tocopherol (alpha-T), alpha-tocopheryl acetate (alpha-TA), or alpha-tocopheryl succinate (alpha-TS). Following incubation, cells were stimulated with 80 microm-PMA. Total cell-associated u-PA, membrane-bound u-PA and free u-PA binding sites were determined before and after stimulation with PMA. Results showed that none of the vitamin E derivatives had any effect (P>0.05) on the u-PA system of resting monocyte-macrophages or neutrophils. In contrast, alpha-TS, but not alpha-TA or alpha-T, increased (P<0.01) total cell-associated u-PA and membrane-bound u-PA of PMA-stimulated macrophages and neutrophils. alpha-TS had no effect (P>0.05) on total u-PA and membrane-bound u-PA activities of macrophages and neutrophils cultured in the presence of 4-phorbol 12,13 didecanoate, a phorbol ester that does not activate protein kinase (PK) C. Addition of H7 (1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride), which is a potent inhibitor of both PK A and C, completely abolished the effect of alpha-TS on total cell-associated u-PA and membrane-bound u-PA of PMA-activated macrophages and neutrophils. Addition of HA1004 (N-(2-quanidinoethyl)-5-isoquinoline sulfonamide hydrochloride), which is a potent PK A but a weak PK C inhibitor, had no effect (P>0.05) on total cell-associated u-PA and membrane-bound u-PA of PMA-activated macrophages and neutrophils cultured in the presence of alpha-TS. Thus, PK C modulates the effect of alpha-TS on the u-PA system of ovine macrophages and neutrophils.

Cellularity and enzymatic activity of adipose tissue in the Karagouniko dairy breed of sheep from birth to maturity.

SUMMARY: The cellular and enzymatic characteristics of dissected subcutaneous and perirenal adipose tissues were examined in a total of 102 male and female animals from commerical flocks of the Karagouniko dairy sheep. The animals were slaughtered in groups of three males and three females at 45-day intervals from birth to 720 days of age. The following determinations were made on each animal: (1) subcutaneous and perirenal chemical fat, (2) fat cell size and number and (3) the activities of NADP-isocitrate dehydrogenase and 6-phosphogluconate dehydrogenase in subcutaneous and perirenal adipose tissues. Subcutaneous adipose tissue expanded by a combination of fat cell hypertrophy and hyperplasia during the accelerating phase of the growth curve of chemical fat, after which the fat expansion was accomplished primarily by hyperplasia. The changes in perirenal chemical fat weight with increasing age were primarily due to hypertrophy of fat cells during the accelerating phase of the curve of chemical fat growth and due to a combination of hypertrophy and hyperplasia during the diminishing phase of the curve. The enzyme activities were higher in subcutaneous than in perirenal adipose tissue, with the NADP-isocitrate dehydrogenase being the most active enzyme in both tissues and sexes. The changes in enzyme activities in subcutaneous adipose tissue with increasing age were parallel to the changes in the rate of chemical fat weight during growth. ZUSAMMENFASSUNG: Zellularitaet und enzymatische Aktivitaet des Fettgewebes beim Karagouniko Milchschaf von der Geburt bis zur Reife. Es wurden die Anzahl und die Groesse der Fettzellen sowie die Aktivitaeten der NADP-Isocitrat-Dehydrogenase und der 6-Phosphogluconat Dehydrogenase in subcutanen und perirenalen Fettgewebe des Schafes waehrend des Wachstums undersucht. Das Tiermaterial bestand aus 51 maennlichen und 51 weiblichen Schafen der Karogouniko Milchrasse. Die Schafe wurden in Gruppen bestehend aus 3 maennlichen und 3 weiblichen Tieren in 45-taegigen Abstaenden von der Geburt bis zum Alter von 720 Tagen geschlachtet. Es wurden die folgenden Merkmale erfasst: Chemisches Fett, Anzahl and Groesse der Fettzellen, Aktivitaeten der gennanten Enzyme. Das subcutane Fettgewebe wuchs durch eine Kombination von Hypertrophie und Hyperplasia waehrend der beschleunigten Phase der Wachstumskurve fuer das chemische Fett. Nach dieser Wachstumsphase, das weitere Wachstum des subcutanen Fettgewebes kam vorwiegend durch Hyperplasia der Fettzellen zustande. Das perirenale Fettgewebe wuchs zunaechst durch Hypertrophie der Fettzellen und anschliessend durch eine Kombinationn von Hypertrophie und Hyperplasia. Die Aktivitaet der NADP-Isocitrat-Dehydrogenase war hoeher als die Aktivitaet der 6-Phosphogluconat-Dehydronase in beiden Geweben und Geschlechtern waehrend der gesamten Versuchsdauer. Die Aenderungen der Enzymaktivitaet waehrend des Wachstums stimmten gut ueberein mit den entsprechenden Aenderungen der taeglichen Wachstumstrate der subcutanen Fettgewebes.