The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Nina Aagaard Poulsen - One of the best experts on this subject based on the ideXlab platform.
-
Mineral and fatty acid composition of milk from native Jutland and Danish Red 1970 cattle Breeds
Acta Agriculturae Scandinavica Section A-animal Science, 2019Co-Authors: Nina Aagaard Poulsen, B D Szekeres, Morten Kargo, Lotte Bach LarsenAbstract:ABSTRACTMineral and fatty acid composition in milk from two minor native Dairy Breeds in Denmark; Danish Red 1970 (RDM-1970) and Jutland cows were analyzed. Results showed that for most composition...
-
protein heterogeneity of bovine β casein in danish Dairy Breeds and association of rare β casein f with milk coagulation properties
Acta Agriculturae Scandinavica Section A-animal Science, 2016Co-Authors: Nina Aagaard Poulsen, A K Rosengaard, B D Szekeres, Vivi Raundahl Gregersen, Hanne Bak Jensen, Lotte Bach LarsenAbstract:ABSTRACTA proteomic approach was applied to characterize genetic variation and relative protein content of β-casein (β-CN) in milk from two minor native Dairy Breeds in Denmark; Red Danish 1970 and Jutland cows in comparison to the major Dairy Breeds; Danish Holstein and Danish Jersey. Genetic β-CN variants were related to the relative concentration of β-CN. Furthermore, a very high frequency of variant F in the native Breeds was found. This was remarkable as this variant is only found in a very low frequency in the major Danish Breeds. Novel associations were found between β-CN variant F and milk coagulation properties in the native Breeds, which is an important finding for understanding the genetic background for non- and poor coagulating milk and potential exploitation of β-CN variants in selective breeding programs. Furthermore, in Red Danish 1970 a very high prevalence of non-coagulating milk was found (18%).
-
the occurrence of noncoagulating milk and the association of bovine milk coagulation properties with genetic variants of the caseins in 3 scandinavian Dairy Breeds
Journal of Dairy Science, 2013Co-Authors: Nina Aagaard Poulsen, Hanne Bak Jensen, F Gustavsson, Maria Glantz, Marie Paulsson, H P Bertelsen, Lindmark H Mansson, Anders Andren, Christian Bendixen, A J BuitenhuisAbstract:Abstract Substantial variation in milk coagulation properties has been observed among Dairy cows. Consequently, raw milk from individual cows and Breeds exhibits distinct coagulation capacities that potentially affect the technological properties and milk processing into cheese. This variation is largely influenced by protein composition, which is in turn affected by underlying genetic polymorphisms in the major milk proteins. In this study, we conducted a large screening on 3 major Scandinavian Breeds to resolve the variation in milk coagulation traits and the frequency of milk with impaired coagulation properties (noncoagulation). In total, individual coagulation properties were measured on morning milk collected from 1,299 Danish Holstein (DH), Danish Jersey (DJ), and Swedish Red (SR) cows. The 3 Breeds demonstrated notable interbreed differences in coagulation properties, with DJ cows exhibiting superior coagulation compared with the other 2 Breeds. In addition, milk samples from 2% of DH and 16% of SR cows were classified as noncoagulating. Furthermore, the cows were genotyped for major genetic variants in the α S1 - ( CSN1S1 ), β- ( CSN2 ), and κ-casein ( CSN3 ) genes, revealing distinct differences in variant frequencies among Breeds. Allele I of CSN2 , which had not formerly been screened in such a high number of cows in these Scandinavian Breeds, showed a frequency around 7% in DH and DJ, but was not detected in SR. Genetic polymorphisms were significantly associated with curd firming rate and rennet coagulation time. Thus, CSN1S1 C , CSN2 B , and CSN3 B positively affected milk coagulation, whereas CSN2 A 2 , in particular, had a negative effect. In addition to the influence of individual casein genes, the effects of CSN1S1 - CSN2 - CSN3 composite genotypes were also examined, and revealed strong associations in all Breeds, which more or less reflected the single gene results. Overall, milk coagulation is under the influence of additive genetic variation. Optimal milk for future cheese production can be ensured by monitoring the frequency of unfavorable variants and thus preventing an increase in the number of cows producing milk with impaired coagulation. Selective breeding for variants associated with superior milk coagulation can potentially increase raw milk quality and cheese yield in all 3 Scandinavian Breeds.
-
the influence of feed and herd on fatty acid composition in 3 Dairy Breeds danish holstein danish jersey and swedish red
Journal of Dairy Science, 2012Co-Authors: Nina Aagaard Poulsen, Lotte Bach Larsen, F Gustavsson, Maria Glantz, Marie Paulsson, M LarsenAbstract:Abstract The composition of milk fat from Dairy cows is related to both genetic and environmental factors. Here, the effect of feed and herd was examined in 3 Scandinavian Breeds, namely Danish Holstein-Friesian (DH), Danish Jersey (DJ), and Swedish Red (SR). In total, milk samples from 1,298 cows kept in indoor housing systems were collected from 61 conventional Dairy herds in Denmark and Sweden. The fatty acid (FA) composition of milk was determined by gas chromatography and the content of α-tocopherol by HPLC. Based on the 17 individual FA determined, distinct FA profiles were observed for all Breeds using univariate and multivariate statistics. The DJ cows were characterized by higher levels of saturated short-chain FA; in contrast, DH cows had higher content of unsaturated C18 FA, whereas higher levels of primarily C14:0, C14:1, C18:1 cis -9, and C18:3n-3 were evident in SR cows. This variation in milk fat composition across Breeds was further reflected in different desaturase indices, which were generally higher in SR cows. In addition, α-tocopherol differed significantly among Breeds, with DJ cows having the highest content. Herd-specific feeding plans were collected, and different feed items were separated into 4 broad feed categories, including grass products, maize silage, grain, and concentrate. The pronounced differences in overall feed composition among Breeds were, to a large extent, due to regional differences between countries, with SR receiving higher levels of grain and grass silage compared with the Danish Breeds. Within Breeds, differences in feeding regimens among herds were furthermore higher in SR. Significant correlations between feed category and individual FA were observed in all Breeds. Furthermore, variance components were estimated and used to determine the proportion of phenotypic variation that could be explained by herd. The herd effect for individual FA was generally lower for DH compared with the 2 other Breeds. In addition, very low herd effects were shown for C14:1 and C16:1 in all Breeds, suggesting that the content of these FA is mainly genetically regulated.
Lotte Bach Larsen - One of the best experts on this subject based on the ideXlab platform.
-
Mineral and fatty acid composition of milk from native Jutland and Danish Red 1970 cattle Breeds
Acta Agriculturae Scandinavica Section A-animal Science, 2019Co-Authors: Nina Aagaard Poulsen, B D Szekeres, Morten Kargo, Lotte Bach LarsenAbstract:ABSTRACTMineral and fatty acid composition in milk from two minor native Dairy Breeds in Denmark; Danish Red 1970 (RDM-1970) and Jutland cows were analyzed. Results showed that for most composition...
-
protein heterogeneity of bovine β casein in danish Dairy Breeds and association of rare β casein f with milk coagulation properties
Acta Agriculturae Scandinavica Section A-animal Science, 2016Co-Authors: Nina Aagaard Poulsen, A K Rosengaard, B D Szekeres, Vivi Raundahl Gregersen, Hanne Bak Jensen, Lotte Bach LarsenAbstract:ABSTRACTA proteomic approach was applied to characterize genetic variation and relative protein content of β-casein (β-CN) in milk from two minor native Dairy Breeds in Denmark; Red Danish 1970 and Jutland cows in comparison to the major Dairy Breeds; Danish Holstein and Danish Jersey. Genetic β-CN variants were related to the relative concentration of β-CN. Furthermore, a very high frequency of variant F in the native Breeds was found. This was remarkable as this variant is only found in a very low frequency in the major Danish Breeds. Novel associations were found between β-CN variant F and milk coagulation properties in the native Breeds, which is an important finding for understanding the genetic background for non- and poor coagulating milk and potential exploitation of β-CN variants in selective breeding programs. Furthermore, in Red Danish 1970 a very high prevalence of non-coagulating milk was found (18%).
-
the influence of feed and herd on fatty acid composition in 3 Dairy Breeds danish holstein danish jersey and swedish red
Journal of Dairy Science, 2012Co-Authors: Nina Aagaard Poulsen, Lotte Bach Larsen, F Gustavsson, Maria Glantz, Marie Paulsson, M LarsenAbstract:Abstract The composition of milk fat from Dairy cows is related to both genetic and environmental factors. Here, the effect of feed and herd was examined in 3 Scandinavian Breeds, namely Danish Holstein-Friesian (DH), Danish Jersey (DJ), and Swedish Red (SR). In total, milk samples from 1,298 cows kept in indoor housing systems were collected from 61 conventional Dairy herds in Denmark and Sweden. The fatty acid (FA) composition of milk was determined by gas chromatography and the content of α-tocopherol by HPLC. Based on the 17 individual FA determined, distinct FA profiles were observed for all Breeds using univariate and multivariate statistics. The DJ cows were characterized by higher levels of saturated short-chain FA; in contrast, DH cows had higher content of unsaturated C18 FA, whereas higher levels of primarily C14:0, C14:1, C18:1 cis -9, and C18:3n-3 were evident in SR cows. This variation in milk fat composition across Breeds was further reflected in different desaturase indices, which were generally higher in SR cows. In addition, α-tocopherol differed significantly among Breeds, with DJ cows having the highest content. Herd-specific feeding plans were collected, and different feed items were separated into 4 broad feed categories, including grass products, maize silage, grain, and concentrate. The pronounced differences in overall feed composition among Breeds were, to a large extent, due to regional differences between countries, with SR receiving higher levels of grain and grass silage compared with the Danish Breeds. Within Breeds, differences in feeding regimens among herds were furthermore higher in SR. Significant correlations between feed category and individual FA were observed in all Breeds. Furthermore, variance components were estimated and used to determine the proportion of phenotypic variation that could be explained by herd. The herd effect for individual FA was generally lower for DH compared with the 2 other Breeds. In addition, very low herd effects were shown for C14:1 and C16:1 in all Breeds, suggesting that the content of these FA is mainly genetically regulated.
-
relationship between the metabolite profile and technological properties of bovine milk from two Dairy Breeds elucidated by nmr based metabolomics
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Ulrik K Sundekilde, Lotte Bach Larsen, Pernille Dorthea Frederiksen, Morten Rahr Clausen, Hanne Christine BertramAbstract:The aim of the present study was to investigate the relationship between the metabolite profile of milk and important technological properties by using nuclear magnetic resonance (NMR)-based metabolomics. The metabolomics approach was introduced for the metabolic profiling of a set of milk samples from two Dairy Breeds representing a wide span in coagulation properties. The milk metabolite profiles obtained by proton and carbon NMR spectroscopy could be correlated to breed and, more interestingly, also with the coagulation profile, as established by traditional methods by using principal component analysis (PCA). The metabolites responsible for the separation into breed could mainly be ascribed to carnitine and lactose, whereas the metabolites varying in the samples with respect to coagulation properties included citrate, choline, carnitine, and lactose. The results found in the present study demonstrated a promising potential of NMR-based metabolomics for a rapid analysis and classification of milk sampl...
-
Variations in coagulation properties of cheese milk from three Danish Dairy Breeds as determined by a new free oscillation rheometry-based method
Dairy Science & Technology, 2011Co-Authors: Pernille D Frederiksen, Mette Bakman, Per Nyegaard Andersen, Jens Bech Andersen, Karsten Bruun Qvist, Marianne Hammershoj, Lotte Bach LarsenAbstract:摘要 - 新型振荡流变法测定源于丹麦三个品种奶牛的干酪用乳的凝乳特性大量文献报道过丹麦的泽西种、丹麦红 (RDM) 种和丹麦荷尔斯坦因-弗里斯兰 (SDM) 种奶牛所产乳的凝乳特性非常差, 甚至不能够凝乳, 本项研究是针对大量的关于这方面的文献报道, 采用新型的自由振荡流变法测定了不同品种干酪用乳凝固特性的变化。以自动挤奶机挤出的牛奶为测定样品, 测定了样品的凝乳酶凝乳时间以及基于储存模量 G’和新鲜脱脂乳的凝块硬化速率所确定的凝块硬度。根据凝固标准, 20%牛奶样品的凝乳特性差, 17%样品加入凝乳酶后能形成较软的凝块, 而3%的样品由于是非凝固的牛奶, 所以在40 min的测定时间内不能够形成凝块。源于泽西奶牛的牛乳的凝固性优于其他两个品种牛乳的凝固性。研究了凝块硬化速率与蛋白质浓度之间的关系, 研究发现 3 种牛乳的凝块硬化速率与蛋白质浓度相关, 这种相关性不仅仅与蛋白质浓度的变化有关, 而是由于蛋白质之间的相互作用。本项研究仅仅是对这类非凝固牛奶的凝乳特性进行了探讨, 为今后进一步研究非凝固牛乳现象产生的原因奠定了基础。AbstractThe paper describes a study on the variation of coagulation properties in individual cow’s milk measured by a novel free oscillation rheometry-based method. The work is part of a study on the occurrence and underlying causes of poorly and even non-coagulating (NC) milk in Denmark, and based on that, the paper reports on the frequency of non- and poorly coagulating milk in a herd of the three main Danish Dairy Breeds, Jersey, Danish red (RDM), and Danish Holstein-Friesian (SDM). The cows were milked by automatic milking. The rennet coagulation time, the coagulum firmness by storage modulus G′, and the curd firming rate of fresh skimmed milk were determined. More than 20% of the milk samples exhibited poor coagulation properties by the criteria set. Of these, the 17% resulted in a weak coagulum after addition of rennet, while another 3% were due to NC milk that did not aggregate to form a curd within the 40 min of measurement. Milk from Jersey cows exhibited superior coagulation properties when compared to milk from SDM and RDM cows. The dependence of curd firming rate on protein concentration was investigated, and found to depend on milk protein concentration to the power of three, emphasizing the importance of protein interactions, and not just the protein concentration itself. The paper gives a basis for the subsequent selection of NC milk samples with the aim to look in more detail for the underlying reasons for the phenomenon of NC milk.
D. Zygoyiannis - One of the best experts on this subject based on the ideXlab platform.
-
fatty acid composition of lambs of indigenous Dairy greek Breeds of sheep as affected by post weaning nutritional management and weight at slaughter
Meat Science, 2006Co-Authors: G Arsenos, D. Zygoyiannis, N Katsaounis, D Kufidis, C. StamatarisAbstract:Abstract The objective was to assess the effect of breed, sex, post-weaning nutrition and weight at slaughter on the fatty acids (FA) composition in carcass fat of lambs of indigenous Greek Dairy Breeds of sheep, the Boutsko (B), Serres (S) and Karagouniko (K) breed. The lambs (weaned at approximately 42 days) had been reared under different conditions of housing and feeding in three consecutive experiments (Experiment). In Experiment 1, lambs ( n = 120) were individually penned and fed ad libitum on a concentrate feed (11.3 MJ metabolisable energy (ME)/kg DM and 192 g crude protein (CP)/kg DM) together with 100 g/day of Lucerne hay (8.3 MJ ME/kg DM and 182 g CP/kg DM). In Experiment 2, lambs ( n = 108) were fed the same concentrate on 3 different levels: High (H), Medium (M) and Low (L) and ad libitum on Lucerne hay. In Experiment 3, lambs ( n = 108) were initially group fed indoors for 63 days on 3 different levels of concentrate (H, M and L) together with ad libitum Lucerne hay. Thereafter they were finished on irrigated, sown pasture. Lambs were slaughtered at one of 5 standard proportions of mature weight (PMW) for each breed in Experiment 1 (i.e. 0.20, 0.30, 0.45, 0.60 and 0.90); at 3 fixed live weights in Experiment 2 (TSLW; i.e. 23, 28 and 33 kg) and at 3 fixed PMW in Experiment 3 (PMW; i.e. 0.20, 0.48 and 0.54). The right hand side of their carcasses was minced and a random sample, around 200 g, was taken. It was freeze-dried and then grounded to obtain a quantity of 2 g for lipid extraction and preparation of fatty acid methyl esters, which were assayed by gas-liquid chromatography to identify. Results were analysed separately for each experiment by analysis of variance. In Experiment 1, breed of lambs had significant effects ( P P P P P P P P
-
The epizootiology of gastrointestinal nematode parasites in Greek Dairy Breeds of sheep and goats
Small Ruminant Research, 2003Co-Authors: Elias Papadopoulos, Georgios Arsenos, Smaragda Sotiraki, C. Deligiannis, T. Lainas, D. ZygoyiannisAbstract:Gastrointestinal (GI) parasitism represents a severe health problem in small ruminant production systems world-wide. The objective of the present study was three-fold: (i) to assess the prevalence of GI parasitism in Dairy Breeds of sheep and goats in selected areas of Greece; (ii) to determine the species of existing gastrointestinal parasites; and (iii) to investigate the effect of climatic factors on the seasonal variation of parasite population dynamics in Dairy sheep and goats reared in two different geographical areas of Greece. The study was conducted in four flocks of either sheep or goats that were equally allocated in northern and central Greece. In each flock, faecal samples were randomly collected from 30 animals at monthly intervals and were used for nematode egg counts and coprocultures. Two animals from each flock were slaughtered monthly and their GI tract were examined for adult worm population and identification. The study revealed that the parasitic burdens in sheep were significantly (P
-
the epizootiology of gastrointestinal nematode parasites in greek Dairy Breeds of sheep and goats
Small Ruminant Research, 2003Co-Authors: Elias Papadopoulos, Georgios Arsenos, Smaragda Sotiraki, C. Deligiannis, T. Lainas, D. ZygoyiannisAbstract:Gastrointestinal (GI) parasitism represents a severe health problem in small ruminant production systems world-wide. The objective of the present study was three-fold: (i) to assess the prevalence of GI parasitism in Dairy Breeds of sheep and goats in selected areas of Greece; (ii) to determine the species of existing gastrointestinal parasites; and (iii) to investigate the effect of climatic factors on the seasonal variation of parasite population dynamics in Dairy sheep and goats reared in two different geographical areas of Greece. The study was conducted in four flocks of either sheep or goats that were equally allocated in northern and central Greece. In each flock, faecal samples were randomly collected from 30 animals at monthly intervals and were used for nematode egg counts and coprocultures. Two animals from each flock were slaughtered monthly and their GI tract were examined for adult worm population and identification. The study revealed that the parasitic burdens in sheep were significantly (P<0.05) higher than those in goats. Faecal egg counts for both sheep and goats were significantly (P<0.01) affected by the month of the year and there was also a significant interaction between month of the year and area of study (P<0.01). Teladorsagia, Haemonchus, Trichostrongylus and Chabertia were the most prevalent nematode genera in both sheep and goats. Such information could be useful for the development of strategic treatments when sheep and goats are reared under systems similar to those described in this study.
-
The use of nutritional management after weaning for the production of heavier lamb carcasses from Greek Dairy Breeds
Livestock Production Science, 1999Co-Authors: D. Zygoyiannis, Georgios Arsenos, N Katsaounis, C. Stamataris, Ln Tsaras, J. M. DoneyAbstract:The present study was conducted to investigate whether nutritional treatments can influence the carcass composition, potential consumer acceptability and cost of rearing, at any defined liveweight (LW) or proportion of breed mature weight (MW), in male lambs of three indigenous Greek Dairy Breeds of sheep. Two trials were carried out each with 30 weaned lambs (about 42 days) of the Boutsko (B), Serres (S) and Karagouniko (K) Breeds. The lambs were reared under different conditions of diet, housing and management and were slaughtered at different degrees of maturity or different slaughter weights. During the first trial, the lambs were individually fed on three levels: high (H), medium (M) and low (L) of concentrate (192 g crude protein/kg DM and 11.3 MJ ME/kg DM) and Lucerne hay (182 g crude protein/kg DM and 8.3 MJ ME/kg DM) offered ad libitum. During the second trial, the lambs were group fed indoors for 63 days on three levels (also denoted as H, M and L) of the same concentrate and Lucerne hay ad libitum, and then finished on irrigated sown pasture (Lolium perenne+Trifolium repens). It was found that in both trials, breed of lambs and concentrate allowances (CA) had a significant effect (P
Marie Paulsson - One of the best experts on this subject based on the ideXlab platform.
-
the occurrence of noncoagulating milk and the association of bovine milk coagulation properties with genetic variants of the caseins in 3 scandinavian Dairy Breeds
Journal of Dairy Science, 2013Co-Authors: Nina Aagaard Poulsen, Hanne Bak Jensen, F Gustavsson, Maria Glantz, Marie Paulsson, H P Bertelsen, Lindmark H Mansson, Anders Andren, Christian Bendixen, A J BuitenhuisAbstract:Abstract Substantial variation in milk coagulation properties has been observed among Dairy cows. Consequently, raw milk from individual cows and Breeds exhibits distinct coagulation capacities that potentially affect the technological properties and milk processing into cheese. This variation is largely influenced by protein composition, which is in turn affected by underlying genetic polymorphisms in the major milk proteins. In this study, we conducted a large screening on 3 major Scandinavian Breeds to resolve the variation in milk coagulation traits and the frequency of milk with impaired coagulation properties (noncoagulation). In total, individual coagulation properties were measured on morning milk collected from 1,299 Danish Holstein (DH), Danish Jersey (DJ), and Swedish Red (SR) cows. The 3 Breeds demonstrated notable interbreed differences in coagulation properties, with DJ cows exhibiting superior coagulation compared with the other 2 Breeds. In addition, milk samples from 2% of DH and 16% of SR cows were classified as noncoagulating. Furthermore, the cows were genotyped for major genetic variants in the α S1 - ( CSN1S1 ), β- ( CSN2 ), and κ-casein ( CSN3 ) genes, revealing distinct differences in variant frequencies among Breeds. Allele I of CSN2 , which had not formerly been screened in such a high number of cows in these Scandinavian Breeds, showed a frequency around 7% in DH and DJ, but was not detected in SR. Genetic polymorphisms were significantly associated with curd firming rate and rennet coagulation time. Thus, CSN1S1 C , CSN2 B , and CSN3 B positively affected milk coagulation, whereas CSN2 A 2 , in particular, had a negative effect. In addition to the influence of individual casein genes, the effects of CSN1S1 - CSN2 - CSN3 composite genotypes were also examined, and revealed strong associations in all Breeds, which more or less reflected the single gene results. Overall, milk coagulation is under the influence of additive genetic variation. Optimal milk for future cheese production can be ensured by monitoring the frequency of unfavorable variants and thus preventing an increase in the number of cows producing milk with impaired coagulation. Selective breeding for variants associated with superior milk coagulation can potentially increase raw milk quality and cheese yield in all 3 Scandinavian Breeds.
-
the influence of feed and herd on fatty acid composition in 3 Dairy Breeds danish holstein danish jersey and swedish red
Journal of Dairy Science, 2012Co-Authors: Nina Aagaard Poulsen, Lotte Bach Larsen, F Gustavsson, Maria Glantz, Marie Paulsson, M LarsenAbstract:Abstract The composition of milk fat from Dairy cows is related to both genetic and environmental factors. Here, the effect of feed and herd was examined in 3 Scandinavian Breeds, namely Danish Holstein-Friesian (DH), Danish Jersey (DJ), and Swedish Red (SR). In total, milk samples from 1,298 cows kept in indoor housing systems were collected from 61 conventional Dairy herds in Denmark and Sweden. The fatty acid (FA) composition of milk was determined by gas chromatography and the content of α-tocopherol by HPLC. Based on the 17 individual FA determined, distinct FA profiles were observed for all Breeds using univariate and multivariate statistics. The DJ cows were characterized by higher levels of saturated short-chain FA; in contrast, DH cows had higher content of unsaturated C18 FA, whereas higher levels of primarily C14:0, C14:1, C18:1 cis -9, and C18:3n-3 were evident in SR cows. This variation in milk fat composition across Breeds was further reflected in different desaturase indices, which were generally higher in SR cows. In addition, α-tocopherol differed significantly among Breeds, with DJ cows having the highest content. Herd-specific feeding plans were collected, and different feed items were separated into 4 broad feed categories, including grass products, maize silage, grain, and concentrate. The pronounced differences in overall feed composition among Breeds were, to a large extent, due to regional differences between countries, with SR receiving higher levels of grain and grass silage compared with the Danish Breeds. Within Breeds, differences in feeding regimens among herds were furthermore higher in SR. Significant correlations between feed category and individual FA were observed in all Breeds. Furthermore, variance components were estimated and used to determine the proportion of phenotypic variation that could be explained by herd. The herd effect for individual FA was generally lower for DH compared with the 2 other Breeds. In addition, very low herd effects were shown for C14:1 and C16:1 in all Breeds, suggesting that the content of these FA is mainly genetically regulated.
Maria Glantz - One of the best experts on this subject based on the ideXlab platform.
-
the occurrence of noncoagulating milk and the association of bovine milk coagulation properties with genetic variants of the caseins in 3 scandinavian Dairy Breeds
Journal of Dairy Science, 2013Co-Authors: Nina Aagaard Poulsen, Hanne Bak Jensen, F Gustavsson, Maria Glantz, Marie Paulsson, H P Bertelsen, Lindmark H Mansson, Anders Andren, Christian Bendixen, A J BuitenhuisAbstract:Abstract Substantial variation in milk coagulation properties has been observed among Dairy cows. Consequently, raw milk from individual cows and Breeds exhibits distinct coagulation capacities that potentially affect the technological properties and milk processing into cheese. This variation is largely influenced by protein composition, which is in turn affected by underlying genetic polymorphisms in the major milk proteins. In this study, we conducted a large screening on 3 major Scandinavian Breeds to resolve the variation in milk coagulation traits and the frequency of milk with impaired coagulation properties (noncoagulation). In total, individual coagulation properties were measured on morning milk collected from 1,299 Danish Holstein (DH), Danish Jersey (DJ), and Swedish Red (SR) cows. The 3 Breeds demonstrated notable interbreed differences in coagulation properties, with DJ cows exhibiting superior coagulation compared with the other 2 Breeds. In addition, milk samples from 2% of DH and 16% of SR cows were classified as noncoagulating. Furthermore, the cows were genotyped for major genetic variants in the α S1 - ( CSN1S1 ), β- ( CSN2 ), and κ-casein ( CSN3 ) genes, revealing distinct differences in variant frequencies among Breeds. Allele I of CSN2 , which had not formerly been screened in such a high number of cows in these Scandinavian Breeds, showed a frequency around 7% in DH and DJ, but was not detected in SR. Genetic polymorphisms were significantly associated with curd firming rate and rennet coagulation time. Thus, CSN1S1 C , CSN2 B , and CSN3 B positively affected milk coagulation, whereas CSN2 A 2 , in particular, had a negative effect. In addition to the influence of individual casein genes, the effects of CSN1S1 - CSN2 - CSN3 composite genotypes were also examined, and revealed strong associations in all Breeds, which more or less reflected the single gene results. Overall, milk coagulation is under the influence of additive genetic variation. Optimal milk for future cheese production can be ensured by monitoring the frequency of unfavorable variants and thus preventing an increase in the number of cows producing milk with impaired coagulation. Selective breeding for variants associated with superior milk coagulation can potentially increase raw milk quality and cheese yield in all 3 Scandinavian Breeds.
-
the influence of feed and herd on fatty acid composition in 3 Dairy Breeds danish holstein danish jersey and swedish red
Journal of Dairy Science, 2012Co-Authors: Nina Aagaard Poulsen, Lotte Bach Larsen, F Gustavsson, Maria Glantz, Marie Paulsson, M LarsenAbstract:Abstract The composition of milk fat from Dairy cows is related to both genetic and environmental factors. Here, the effect of feed and herd was examined in 3 Scandinavian Breeds, namely Danish Holstein-Friesian (DH), Danish Jersey (DJ), and Swedish Red (SR). In total, milk samples from 1,298 cows kept in indoor housing systems were collected from 61 conventional Dairy herds in Denmark and Sweden. The fatty acid (FA) composition of milk was determined by gas chromatography and the content of α-tocopherol by HPLC. Based on the 17 individual FA determined, distinct FA profiles were observed for all Breeds using univariate and multivariate statistics. The DJ cows were characterized by higher levels of saturated short-chain FA; in contrast, DH cows had higher content of unsaturated C18 FA, whereas higher levels of primarily C14:0, C14:1, C18:1 cis -9, and C18:3n-3 were evident in SR cows. This variation in milk fat composition across Breeds was further reflected in different desaturase indices, which were generally higher in SR cows. In addition, α-tocopherol differed significantly among Breeds, with DJ cows having the highest content. Herd-specific feeding plans were collected, and different feed items were separated into 4 broad feed categories, including grass products, maize silage, grain, and concentrate. The pronounced differences in overall feed composition among Breeds were, to a large extent, due to regional differences between countries, with SR receiving higher levels of grain and grass silage compared with the Danish Breeds. Within Breeds, differences in feeding regimens among herds were furthermore higher in SR. Significant correlations between feed category and individual FA were observed in all Breeds. Furthermore, variance components were estimated and used to determine the proportion of phenotypic variation that could be explained by herd. The herd effect for individual FA was generally lower for DH compared with the 2 other Breeds. In addition, very low herd effects were shown for C14:1 and C16:1 in all Breeds, suggesting that the content of these FA is mainly genetically regulated.
