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Productive performance and composition of milk protein fraction in dairy cows supplemented with fat sources
Freitas Júnior, José Esler de;Rennó, Francisco Palma;Santos, Marcos Veiga dos;Gandra, Jefferson Rodrigues;Maturana Filho, Milton;Venturelli, Beatriz Conte;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000400021
Abstract: the objective of this study was to evaluate the use of fat sources in rations for lactating cows on the productive performance and composition of milk protein fraction. twelve holstein cows were used, grouped in three balanced 4 × 4 latin squares, fed with the following rations: control; refined soybean oil; whole raw soybean; and calcium salts of unsaturated fatty acid (megalac-e). dry matter and nutrient intake, and daily milk production were evaluated. the samples used to analyze milk composition were collected in two alternate days and were obtained from two daily milking. milk composition and total nitrogen, non-protein nitrogen and non-casein nitrogen ratios were analyzed. the casein, serum protein and true protein ratios were obtained by difference. dry matter and nutrient intakes were lower when cows received the diet containing calcium salts of fatty acids, in relation to the control diet. among the diets with fat sources, the one with whole raw soybean and calcium salts decreased milk production. there was no effect of fat sources added to the diet on crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/milk true protein ratio and serum protein. similarly, the experimental diets did not influence the protein fractions when expressed in percentage of milk crude protein. the utilization of fat sources in diets changes milk production and composition of lactating cows, but does not influence the composition of milk protein fractions.
Productive performance and milk protein fraction composition of dairy cows supplemented with sodium monensin
Gandra, Jefferson Rodrigues;Rennó, Francisco Palma;Freitas Júnior, José Esler de;Santos, Marcos Veiga dos;Silva, Luís Felipe Prada e;Araújo, Ana Paula Chaves de;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000800025
Abstract: the objective of this work was to evaluate the levels of sodium monensin on lactating cows and their effects on productive performance and milk protein fraction composition. it was used 12 holstein cows, distributed in four balanced 3 × 3 latin squares, and fed three diets: one control without monensin, and two diets with monensin at the levels of 24 or 48 mg/kg dm added to the concentrate. milk production was daily measured throughout the entire experimental period. the samples used for analysis of milk composition were collected on two alternated days from the two daily milking. non-protein nitrogen, total nitrogen and non-casein nitrogen contents were directly evaluated in the milk, and casein, whey protein and true protein contents were indirectly determined. the use of monensin in the rations reduced dry matter and nutrient intake, especially when diet with 48 mg/kg of dry matter was given. the ration with 24 mg/kg of dm increased milk production, with or without correction, and also fat and lactose yield, and it improved productive efficiency. the levels of monensin in the ratios did not influence contents of milk crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/true protein ratio, whey protein, and of all those fractions expressed as percentage of crude protein. the utilization of monensin in the ratio at the dose of 24 mg/kg of dm influences positively the productive performance of lactating cows, and it does not influence the composition of milk protein fractions.
Comparison of fatty acid composition in conventional and organic milk  [cached]
Anka Popovi? Vranje?,Milan Krajinovi?,Jelena Kecman,Sne?ana Trivunovi?
Mljekarstvo , 2010,
Abstract: The goal of the scientific research was to establish the differences between fatty acid composition in conventional milk and milk produced according to the organic production principles. In the period between February and December in 2009, the samples of raw conventional milk were analysed using the gas chromographic method to determine the fatty acid composition. Conventional milk was produced at the farm with around 700 dairy cows of Holstein breed. The farm is located in the Vrbas municipality. Organic milk was sampled from ten smaller farms with 12 dairy cows of Simmental breed on the average, located in clean environment of Fru ka Gora slopes (Grabovo settlement). The results of fatty acids content were processed with the statistical package (Statistica 9), and a significant differences were determined with t-test and shown as statistically significant (p<0.05) and highly statistically significant (p<0.01). Conventional milk had a higher content of the monounsaturated fatty acids in comparison with organic milk (p<0.05). In terms of polyunsaturated and omega-3 fatty acids content, organic milk was richer in comparison with conventional milk and these differences were statistically highly significant (p<0.01). The differences in the content of saturated and omega-6 fatty acids were not shown as statistically significant (p>0.05). The ratio of omega-6 to omega-3 in organic milk was lower than in conventional milk, which is crucial to human health. The differences in fatty acid composition between conventional and organic milk may result from different feeding practices, because the organic breeding of cows is primarily based on grazing, while the conventional breeding implies mixed ration.
Comparison of the milk composition of free-ranging indigenous African cattle breeds
J Myburgh, G Osthoff, A Hugo, M de Wit, K Nel, D Fourie
South African Journal of Animal Science , 2012,
Abstract: The milk composition of free-ranging indigenous African cattle breeds was analysed. These breeds were chosen because they have not been bred specifically for milk production and might be considered the closest to a “natural” or “wild type” of the Bos species. It was found that the nutrient composition of the milk of these cattle, in particular the dry matter, is as low as that of European beef breeds. The content of whey proteins and NPN is also lower than that of dairy breeds. Statistically significant differences in milk fatty acid composition between the Sanga-type cattle and the Afrikaner and its derivatives were observed for the content of lactose, whey protein and non-protein nitrogen, as well as fatty acid composition regarding medium long chain and long chain fatty acids. A genetic relationship is evident and suggests the preference of certain fatty acid synthesis pathways.
Brown Midrib forage sorghum silage for the dairy cow: nutritive value and comparison with corn silage in the diet  [cached]
Stefania Colombini,Luca Rapetti,Daniele Colombo,Gianluca Galassi
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2010.e53
Abstract: Rumen dry matter and fibre digestibility of brown midrib (BMR) sorghum forage silage (SF) in comparison to corn silage (CS) was determined in situ using 3 fistulated dry cows. The effect of replacing CS with SF on milk production was studied in a change-over design with 58 lactating Italian Friesian cows fed two diets with similar composition. CS had a higher (P<0.001) rapidly degradable dry matter (DM) fraction than SF (33.1 vs. 23.7, respectively), whilst the slowly degradable fraction was not different (46.3 vs. 48.7). Overall, the extent of DM rumen degradability was higher for CS. Rumen digestion rate of neutral detergent fibre (aNDFom) tended to be higher (P=0.06) for SF than CS (3.08 vs. 2.49 %/h, respectively); however, effective rumen degradability of fibre was not different between silages. Neither milk yield (kg/d) and 4%-fat corrected milk nor milk protein and fat contents were affected by treatment. Cows fed CS diet had lower (P<0.05) milk urea content compared with their SF counterparts (19.9 vs. 21.5 mg/dL,) suggesting a better nitrogen utilization at the rumen level. In conclusion, feeding a BMR sorghum forage resulted in milk yield and quality similar to corn silage. However, to obtain comparable milk production as corn silage, the SF-based diet had to be supplemented with more starch from corn meal.
Yoghurt fermentation trials utilizing mare milk: comparison with cow milk
G. Civardi,T.M.P. Cattaneo,M. Orlandi,M.C. Curadi
Italian Journal of Animal Science , 2011, DOI: 10.4081/ijas.2003.s1.598
Abstract: Mare milk shows a very interesting nutritional composition, similar to human milk. Whey protein fraction represents about 50% of total proteins, with a good amount of essential amino acids, and high lysozyme concentration (Jauregui-Adell, 1975). Mare milk contains essential fatty acids, progenitors of ω3 and ω6, higher than cow milk (Csapò et al., 1995; Curadi et al., 2002). In east european countries mare milk is utilized in dietetics and therapeutics for gastroenteric and cardiac pathologies (Sharmanov et al., 1982; Mirrakimov et al., 1986), or as a drink obtained from lactic and alcoholic fermentation (Koumiss)...
Protein fraction heterogeneity in donkey’s milk analysed by proteomic methods
D. Marletta,A. Criscione,V. Cunsolo,A. Zuccaro
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.1s.650
Abstract: Donkey’s milk is often well tolerate by patients affected by cow’s milk protein allergy, probably thanks to its protein composition. This empiric evidence, confirmed by some clinical trials, needs to be better investigated. A preliminary survey on the protein fraction of donkey’s milk was carried out: fifty-six individual milk samples have been collected and analysed by IEF and SDS-PAGE. Five different IEF patterns have been identified, showing a marked heterogeneity both in casein and whey protein fractions. A single IEF pattern showed an apparent reduced amount of casein fraction highlighted by SDS. Three of the five IEF patterns have been further investigated by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS).
Chemical composition of the essential oil and hexanic fraction of Lippia and Lantana species
Silva, Pamela S.;Viccini, Lyderson F.;Singulani, Junya L.;Siqueira, Ezequias Pessoa de;Zani, Carlos L.;Alves, Tania M. A.;
Revista Brasileira de Farmacognosia , 2010, DOI: 10.1590/S0102-695X2010005000040
Abstract: a comparison between two extraction approaches of volatiles compounds from six species of verbenaceae collected at serra do cipó, minas gerais, brazil was done. the essential oil and hexanic fraction of leaves from two lantana and four lippia species collected in two different seasons were analyzed by gc/ms. among various identified compounds from both extraction methods the majority of species showed major amounts of β-caryophyllene followed by germacrene d, bicyclogermacrene and α-pinene. few differences were observed between the composition of essential oil and the hexanic fraction regarding the two studied genera. these results suggest that the analysis of hexanic fraction can be used, as an alternative way, to analyze the volatile compounds of the essential oil.
Comparative Protein Composition Analysis of Goat Milk Produced by the Alpine and Saanen Breeds in Northeastern Brazil and Related Antibacterial Activities  [PDF]
Whyara Karoline Almeida da Costa, Evandro Leite de Souza, Edvaldo Mesquita Beltr?o-Filho, Gracy Kelly Vieira Vasconcelos, Tatiane Santi-Gadelha, Carlos Alberto de Almeida Gadelha, Octavio Luiz Franco, Rita de Cássia Ramos do Egypto Queiroga , Marciane Magnani
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093361
Abstract: The protein composition of goat milk differs between goat breeds and could present regional trends. The aim of this study was to comparatively analyze the protein composition of goat milk produced by the Alpine and Saanen breeds in northeastern Brazil and to evaluate the antibacterial activity of its protein fractions. SDS-PAGE, 2-DE electrophoresis and RP-HPLC analyses revealed the absence of αs1-casein in the milk of both breeds and no differences between the αs2-casein, β-casein, β-lactoglobulin and α-lactalbumin profiles. The amounts of soluble proteins and β-casein hydrolysis residues were higher in Saanen milk. Only the protein fraction containing the largest amounts of casein (F60–90%) inhibited bacterial growth, with MIC values between 50 and 100 mg/mL. This study describe for the first time three important points about the goat milk protein of two Brazilian goat breeders: absence of α-s1 casein in the protein profile, differences between the milk protein composition produced by goats of Alpine and Saanen breeders and antibacterial activity of unbroken proteins (casein-rich fraction) present in these milk.
A comparison between single and composite milk samples for the genetic evaluation of milk composition in dairy cattle
R Van Dyk, FWC Neser, FH Kanfer
South African Journal of Animal Science , 2002,
Abstract: A simulation study was carried out to compare the use of single and composite milk samples for the evaluation of milk composition in dairy cattle. The genetic correlation between the two sampling methods was estimated. Results showed a high genetic correlation between the breeding values arrived from composite and single samples. This indicates that the same genes are possibly responsible for both traits, which makes it possible to use a single sample, instead of a composite sample, in predicting breeding values. South African Journal of Animal Science Vol.32(1) 2002: 44-49
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