1,721,067 research outputs found
Fattori che influenzano le caratteristiche chimiche e nutrizionali dei prodotti lattiero-caseari
No full textNeutral Detergent Fibre (NDF) and Non Structural Carbohydrate (NSC) requirements in the nutrition of dairy ewes
No full textThe aim of this review was to contribute to the knowledge of neutral detergent fibre (NDF) and non structural carbohydrate
(NSC) requirements in the nutrition of dairy ewes. NDF and NSC requirements were evaluated by analysing a
dataset that involved 30 experimental trials carried out from 1985 to 2003. The dataset included chemical composition
of the experimental diets, individual milk yield, body weight, milk protein and fat content. These selected papers regard
10 different dairy ewe breeds (Valle del Belice, Bergamasca, Comisana, Delle Langhe, Massese, Sarda, Chios,
Manchega, Lacaune and Friesian) and lactating ewes in mid lactation, kept under non homogeneous environmental and
feeding conditions. Results substantially confirmed that which was recently reported in literature: NDF requirements are
higher in late lactation than during early lactation and they vary between 33-38% on DM, while NSC requirements are
higher during early lactation than in late lactation when the energy from NSC promotes an increase in fat deposits
Strategie nutrizionali per il miglioramento della frazione lipidica degli alimenti di origine animale
No full textLipid requirements in the nutrition of dairy ewes
No full textThe aim of this review was to contribute to the knowledge of lipid requirements in dairy ewes, by reviewing experimental
papers about lipid supplementation in dairy ewe feeding. The number of trials in ewe feeding is lower than that
in dairy cow feeding and, leaving calcium soap of palm oil out of consideration, there is a lack of knowledge regarding
the effects of protected and unprotected lipid sources on milk yield and quality from dairy ewes. On the basis of data
reported in the literature, the optimal dose of calcium soap of palm oil resulted to be 100-120 g/d. Also, milk fatty acid
composition may be improved by adding calcium soap of fatty acids to ewe diets. The general effect of calcium salt supplementation
is an increase in milk unsaturated fatty acids and a decrease in saturated ones. However, more research
is needed in order to explain the effect of different fat sources (protected and unprotected) on milk yield and quality
from dairy ewes
Effects of omega-3 and CLA on nutritional traits of foods of animal origin
No full textThe major components of the fatty fraction of foods of animal origin are reviewed: saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), ω-3 and ω-6 polyunsaturated fatty acids (n-3 and n-6 PUFA), conjugated linoleic acid isomers (CLA). The biological and/or pathological actions of each component are synthetically described and the following indications are given: i) SFA should not be higher than 10% of total energy intake; ii) trans MUFA from hydrogenation processing must be avoided because harmful, whereas vaccenic acid (C18:1 t11), which is naturally formed within the rumen and is consequently present in dairy products doesn’t seem to be of harm; iii) n-3 PUFA are preventing factors of either coronary heart disease or some kinds of tumours; iv) n-6 PUFA are modulators of vascular functions and precursors of some isomers of prostaglandins; v) n-6/n-3 ratio must be as close to 1 as possible; vi) CLA exerts several functions essential for preventing disorders of lipid metabolism, of coronary heart disease, of some tumours and of diabetes. It is concluded that the diet of the average Western citizen is quite often unbalanced and must be re-conducted to the recommended allowances, even by means of animal nutrition
Effect of chestnut and quebracho tannins on fatty acid profile in rumen liquid- and solid-associated bacteria: an in vitro study
No full textTannins are phenolic compounds that interfere with biohydrogenation (BH) of polyunsaturated fatty acids (FAs). The aim of the present in vitro study was to investigate the effects of two different sources of tannins on FA profiles of rumen bacteria, with particular reference to rumenic and vaccenic acid. A control diet (C; composed of 300 g/kg of wheat straw, 132 g/kg of soyabean meal, 96 g/kg of barley meal, 152 g/kg of maize meal, 300 g/kg of maize gluten and 20 g/kg of mineral vitamin premix, all expressed on dry matter (DM)) and four diets, obtained by adding to C two different types of tannins from chestnut (TC) and from quebracho (TQ) at two concentration levels (49 and 82 g/kg DM), were compared. The content of the main unsaturated FAs (C18:1 cis9, C18:1 trans11, C18:2 cis9, cis12 and C18:3 cis9, cis12, cis15) from solid-associated bacteria (SAB) and liquid- associated bacteria (LAB) was affected by the presence of tannins in the diets. In particular, C18:1 trans11 content was significantly increased, especially with TC1, whereas the decreasing of C18:1 cis9 was unaffected, regardless of the presence or the kind of tannins added to feeds. SAB contained higher amounts of intermediates of polyunsaturated FA BH (as C18:1 trans11 and C18:2 cis9, trans11) than LAB that were characterized by a higher amount of C18:0. In the concentration range adopted in this study, the effect of TC and TQ on changes of bacterial FA profile was comparable. Tannins seem to be a good means to modulate the FA profile of rumen bacteria, favouring the accumulation of C18:1 trans11 during in vitro rumen fermentation
Effect of dried or green forage on vaccenic and conjugated linoleic acid production during in vitro rumen fermentation
No full textEffect of dried or green forage on vaccenic and conjugated linoleic acid production during in vitro rumen fermentatio
Repeatability and reproducibility of the Cornell Net Carbohydrate and Protein System analytical determinations
No full textThe increasing use in Italy of the Cornell Net Carbohydrate and Protein System (CNCPS) led researchers of five Italianuniversities to carry out a collaborative study to evaluate the precision of the CNCPS chemical analysis and derivate fractions.Each laboratory conducted in duplicate the chemical analyses according to the Weende (dry matter; crude protein;ether extract; crude fibre; ash), Van Soest (neutral and acid detergent fibre, NDF and ADF; acid detergent lignin; ADL)and CNCPS (soluble proteins, SP; non-protein nitrogen, NPN; neutral and acid detergent insoluble protein, NDIP andADIP; starch, ST) schemes on the same five feeds (barley meal, wheat straw, maize silage, dried lucerne and fieldbeans). Anomalous analytical data were identified and corrected by the "box-plot" graphic tool before the calculation ofthe CNCPS protein (B 1, B 2, and B 3,) and carbohydrate (A, B 2 and C) fractions. Finally, repeatability (chemical analysis) andreproducibility (chemical analysis and fractions) were calculated and expressed as relative values (repeatability andreproducibility standard deviation as percentage of the corresponding mean, RSDr and RSDR, respectively). Chemicalanalyses of the Weende scheme, together with NDF, ADF and ST analyses, have satisfactory repeatability (0.3-6.2%) andreproducibility (0.3-11.2%) values. On the contrary the ADL, NPN, NDIP and ADIP analyses showed high variability, bothwithin and between laboratories (RSD r and RSD R between 20 and 45%). The SP analysis had an intermediate value ofprecision (RSD r=10.6%; RSDR=16.4%).Finally, since different combinations of several chemical analyses with scarce (ADL, NPN, NDIP, ADIP, SP) or average precision(e.g. NDF and starch) are used to calculate CNCPS fractions (excluding B 2 protein fraction), also the reproducibilitiesof these fractions are poor and range from 10 to 20%
Effetto della somministrazione orale di tannini di castagno sulla risoluzione della diarrea nel vitello lattante
No full textLa diarrea neonatale è una delle principali cause di perdite economiche nell’allevamento bovino da latte. I tannini di castagno hanno un effetto astringente e antinfiammatorio sul tratto gastro-enterico e sono comunemente utilizzati come fitoterapici per questi scopi in alcune specie. Lo scopo del presente lavoro è stato quello di valutare l’effetto della somministrazione orale di tannini di castagno (Castanea sativa) sulla risoluzione della diarrea nel vitello lattante.
Sono stati inclusi 24 vitelli di razza Frisona Italiana e età compresa fra 0 e 60 giorni che presentassero diarrea con fecal score ≥1. I soggetti sono stati suddivisi in due gruppi e la durata della diarrea è stata registrata: gruppo A ha ricevuto Effydral® in 2 L di acqua tiepida; gruppo B ha ricevuto Effydral® in 2 L di acqua tiepida + 10 g di estratto di tannini di castagno in polvere. E’ stato eseguito T-test di Student per verificare differenze tra i due gruppi relative alla durata della diarrea. Sono stati considerati statisticamente significativi valori di p<0.05.
La durata della diarrea è stata di 10.1±3.2 giorni nel gruppo A e 6.6±3.8 giorni nel gruppo B, con una differenza statisticamente significativa tra i due gruppi (p=0.02).
La durata inferiore della diarrea nel gruppo B rispetto al gruppo A fa ipotizzare un’effettiva azione astringente di questi fitoterapici nel vitello, come già riportato nell’uomo. L’utilizzo dei tannini di castagno nella diarrea del vitello lattante sembra abbreviarne la durata di quasi 4 giorni e potrebbero rappresentare un ausilio a basso impatto economico ed ambientale nel trattamento delle diarree neonatali.
Parole chiave: vitello, diarrea neonatale, tannin
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