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Effect of lactation on energy metabolism in dairy cows from different categories
Celeska Irena,Ul?ar Igor,Stojkovski Velimir,Dovenski Toni
Macedonian Veterinary Review , 2010,
Abstract: The aim of this article was determination of the energy status of Holstein-Friesian cows in three dairy farms in our country. For that purpose, blood samples were taken from three different farms with similar diet for dairy cows. Blood samples were taken from clinically healthy cows, from 2nd to 7th lactation. Several biochemical parameters were measured for determination of the energy status: glucose, non-esterified fatty acids, β-hydroxybutirate (BHB), triacylglycerols and total cholesterol. Total of N=378 samples were taken from multiparous Holstein-Friesian dairy cows from all categories. Cows were divided into three main groups. The group 1 was formed of dry cows, and it was divided into two subgroups: “far from calving” (n=64) and “close up to calving” (n=62). The animals in the group 2 - early lactation cows, were divided into three subgroups as follows: up to 14 days after calving (n=66), up to 60 days after calving (n=63) and up to 100 days after calving (n=62). The group 3 was with cows that were in middle lactation, more than 100 days after calving (n=61). Biochemical parameters were analyzed with standard colorimetric methods, using Sentinel and Randox reagents, on photometer Stat Fax 3300 (Awareness Technology Inc.). These results have shown that dairy cows developed hypoglycemia and early lipolysis (high level of serum NEFA and BHB), during the dry period. The obtained results confirm the ability of the dairy cows for adaptation in various hysiological stages of lactation, but the actual system of feeding does not allow them to achieve their genetic potential. Finally, the evident health problems, occurring as a result of managerial and nutritional errors on the dairy farms, defined as “production diseases” are the most serious cause for decreased production effects.
Effect of Chromium Propionate Supplementation on Lactation Performance and Blood Parameters of Dairy Cows
Xin Jin,Shengli Li,Wanjin Zhang
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.3031.3035
Abstract: The objective of this study was to determine the effect of chromium propionate (Cr, 0.4%) supplementation on lactation performance and blood parameters of dairy cows. One hundred primiparous Holstein cows were grouped based on parity and randomly assigned to five supplemental doses (I, II, III, IV, V) of 0, 25, 50, 100 and 150 mg of Cr propionate/kg of concentrate. Experimental diets were fed from approximately 30 days prepartum until 60 days postpartum. Lactation performance: Cr Prop addition did not affected fat, protein, lactose in milk but supplementation of 50 mg of Cr propionate/kg of concentrate did decrease SCC and increase DMI and milk yield. Blood indicators: Addition of Cr can increase serum glucose except the treatment of 150 mg, increase the content of Cr in serum and decrease β-hydroxyl butyrate and NEFA.
Red blood count in dairy cows in periparturient period and in early lactation  [PDF]
Davidovi? Vesna,Joksimovi?-Todorovi? Mirjana,Hristov Slav?a,Stankovi? Branislav
Veterinarski Glasnik , 2011, DOI: 10.2298/vetgl1106313d
Abstract: The paper presents results of red blood count studies in dairy cows in the periparturient period and early lactation, when cows are in a state of extreme stress due to intensive endocrine and metabolic changes. Investigations were carried out on 20 cows of the Holstein-Friesian breed which were in their second to fifth lactation. Blood samples were drawn 15 days before calving, on the first day after partus (2-5h) and on days 15, 30, and 45 of lactation. The biggest average number of erythrocytes (7.00±0.48×1012/L blood), haemoglobin concentration (115.95±8.49 g/L blood) and haematocrit value (33.11±2.97%) were established on the first day after partus. This erythrocyte count was significantly higher against the value determined during the last two week of gravidity (p<0.01) and during the early stage of lactation (p<0.001). Haemoglobin and haematocrit concentration in the prepartal period and immediately after calving were statistically significantly higher (p<0.001) than on days 15, 30, and 45 of lactation. Haematological indexes: the average erythrocyte volume (MCV), average haemoglobin value in erythrocytes (MCH) and average haemoglobin concentration in erythrocytes (MCHC) were within the limits of the referent values. On the first day of partus, the erythrocyte sedimentation rate was significantly higher than in early lactation (p<0.01 on days 15 and 30, and p<0.001 on day 45). The results of the analyses indicated a decrease in all examined haematological parameters during the period of lactation, but the determined differences were not significant.
Resistin in Dairy Cows: Plasma Concentrations during Early Lactation, Expression and Potential Role in Adipose Tissue  [PDF]
Maxime Reverchon, Christelle Ramé, Juliette Cognié, Eric Briant, Sébastien Elis, Daniel Guillaume, Jo?lle Dupont
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093198
Abstract: Resistin is an adipokine that has been implicated in energy metabolism regulation in rodents but has been little studied in dairy cows. We determined plasma resistin concentrations in early lactation in dairy cows and investigated the levels of resistin mRNA and protein in adipose tissue and the phosphorylation of several components of insulin signaling pathways one week post partum (1 WPP) and at five months of gestation (5 MG). We detected resistin in mature bovine adipocytes and investigated the effect of recombinant bovine resistin on lipolysis in bovine adipose tissue explants. ELISA showed that plasma resistin concentration was low before calving, subsequently increasing and reaching a peak at 1 WPP, decreasing steadily thereafter to reach pre-calving levels at 6 WPP. Plasma resistin concentration was significantly positively correlated with plasma non esterified fatty acid (NEFA) levels and negatively with milk yield, dry matter intake and energy balance between WPP1 to WPP22. We showed, by quantitative RT-PCR and western blotting, that resistin mRNA and protein levels in adipose tissue were higher at WPP1 than at 5 MG. The level of phosphorylation of several early and downstream insulin signaling components (IRβ, IRS-1, IRS-2, Akt, MAPK ERK1/2, P70S6K and S6) in adipose tissue was also lower at 1 WPP than at 5 MG. Finally, we showed that recombinant bovine resistin increased the release of glycerol and mRNA levels for ATGL (adipose triglyceride lipase) and HSL (hormone-sensitive lipase) in adipose tissue explants. Overall, resistin levels were high in the plasma and adipose tissue and were positively correlated with NEFA levels after calving. Resistin is expressed in bovine mature adipocytes and promotes lipid mobilization in adipose explants in vitro.
Pten Regulates Development and Lactation in the Mammary Glands of Dairy Cows  [PDF]
Zhuoran Wang, Xiaoming Hou, Bo Qu, Jie Wang, Xuejun Gao, Qingzhang Li
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0102118
Abstract: Pten is a tumor suppressor gene regulating many cellular processes, including growth, adhesion, and apoptosis. In the aim of investigating the role of Pten during mammary gland development and lactation of dairy cows, we analyzed Pten expression levels in the mammary glands of dairy cows by using western blotting, immunohistochemistry, and quantitative polymerase chain reaction (qPCR) assays. Dairy cow mammary epithelial cells (DCMECs) were used to study the function of Pten in vitro. We determined concentrations of β-casein, triglyceride, and lactose in the culture medium following Pten overexpression and siRNA inhibition. To determine whether Pten affected DCMEC viability and proliferation, cells were analyzed by CASY-TT and flow cytometry. Genes involved in lactation-related signaling pathways were detected. Pten expression was also assessed by adding prolactin and glucose to cell cultures. When Pten was overexpressed, proliferation of DCMECs and concentrations for β-casein, triglyceride, and lactose were significantly decreased. Overexpression of Pten down-regulated expression of MAPK, CYCLIN D1, AKT, MTOR, S6K1, STAT5, SREBP1, PPARγ, PRLR, and GLUT1, but up-regulated 4EBP1 in DCMECs. The Pten siRNA inhibition experiments revealed results that opposed those from the gene overexpression experiments. Introduction of prolactin (PRL) increased secretion of β-casein, triglyceride, and lactose, but decreased Pten expression levels. Introduction of glucose also increased β-casein and triglyceride concentrations, but did not significantly alter Pten expression levels. The Pten mRNA and protein expression levels were decreased 0.3- and 0.4-fold in mammary glands of lactating cows producing high quality milk (milk protein >3.0%, milk fat >3.5%), compared with those cows producing low quality milk (milk protein <3.0%, milk fat <3.5%). In conclusion, Pten functions as an inhibitor during mammary gland development and lactation in dairy cows. It can down-regulate DCMECs secretion of β-casein, triglyceride, and lactose, and plays a critical role in lactation related signaling pathways.
Effects of Niacin on Milk Production and Blood Parameters in Early Lactation of Dairy Cows
Behnam Ghorbani,Narges Vahdani,Saeed Zerehdaran
Pakistan Journal of Biological Sciences , 2008,
Abstract: To investigate the effects of niacin supplementation in the diet of high producing cows at early lactation, 21 holstein dairy cows were used in this experiment. Animal were assigned in to three groups based on their milk yield and calving date soon after parturition. They were received a basal diet and 0 (group 1), 6 (group 2), 12 (group 3) g of supplementation niacin per day over a 10 weeks experimental period. Milk volume was recorded and milk samples were collected for each cow at two weeks interval for analysis of fat, protein, lactose and SNF (Solid-None Fat). Blood samples were also taken for the measurement of glucose, triglyceride, Beta-hydroxy butyrate and total protein at two weeks intervals. No significant difference were observed between milk yield, milk fat , protein, lactose and SNF content in cows received niacin compared to the control group (p>0.05). Plasma glucose in groups 2 and 3 compared to the control were higher and this difference were statistically significant (p<0.05). Blood triglycerides were not significantly affected by niacin supplementation. BHBA were lower in cows received niacin and this difference were significant (p<0.05). The trend of changes in the amount of blood total protein were identical in all three groups whole the level of this factor was always higher in control group compared to the others groups. Niacin has showed an increase in the level of plasma glucose and a notable decrease in the amount of blood triglyceride, β -hydroxy butyrate and total protein, which may be due to the effect of this vitamin on the energy metabolism in cows.
Effects of Monensin and Increasing Crude Protein in Early Lactation on Performance of Dairy Cows  [PDF]
Behnam Ghorbani,Taghi Ghoorchi,Hamid Amanlou,Saeed Zerehdaran
Pakistan Journal of Biological Sciences , 2008,
Abstract: Twenty-four Holstein dairy cows were used to evaluate the singular and combined effects of different level of crude protein and monensin treatments during the early lactation on digestion and milk yield of dairy cows. The experiment was designed as completely randomized with a 3x2 factorial arrangement of treatments. The factors were three Concentrations of CP supplement (19.5, 21.4 and 23.4% of dry matter) and two levels of monensin (0 and 350 mg per cow per day). This experiment consist of three periods and each period was 3 week in length. Monensin did not affect DMI, milk yield, lactose and SNF but it reduced milk fat and protein percentage. Monensin premix significantly decreased rumen ammonia but rumen pH and microbial protein synthesis was not affected by monensin treatment. Although, Monensin treatment increased apparent digestibility of DM, NDF, ADF, CP, but they were not significantly. Increasing dietary CP, improved milk and protein production, but did not alter the other components of milk. Digestibility of NDF, ADF, CP were improved by increasing dietary CP. Increasing diet CP from 19.5 to 21.4% did not significantly increase ruminal ammonia, but increasing to 23.4% have significant effect on it. There was a linear relationship between level of crud protein in the diet and urine volume excretion. Microbial protein synthesis was affected by increasing CP level; on this way maximum protein synthesis was achieved in 21.4% CP.
High grain diets perturb rumen and plasma metabolites and induce inflammatory responses in early lactation dairy cows
D. G.V. Emmanuel,S. Shanthipoosan,B. N. Ametaj
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.1s.424
Abstract: Immediately after parturition dairy cows are fed diets containing high proportions of grain which are associated with high incidence of metabolic disorders. However, the reason behind these effects is not clear. The goal of this study was to investigate metabolic and immune responses of early postpartum dairy cows to feeding increasing proportions of barley grain in the diet. Rumen endotoxin content increased several fold and rumen fluid pH was lower in cows fed the highest amount of barley grain. Results indicate that feeding high proportions of barley grain in early lactation dairy cows was associated with induction of an acute phase response and changes in multiple plasma metabolites. Further research is warranted to understand the mechanism(s) by which feeding of barley grain causes disturbances in plasma metabolites and stimulates an inflammatory response in dairy cows.
HAEMATOLOGICAL PARAMETERS IN EXOTIC COWS DURING GESTATION AND LACTATION UNDER SUBTROPICAL CONDITIONS
A. SATTAR AND R. H. MIRZA1
Pakistan Veterinary Journal , 2009,
Abstract: Seventy Holstein-Friesian and Jersey cows of different ages kept at the Livestock Experiment Station, Bhunikey (Pattoki), district Kasur, Pakistan were used for this study. These cows were divided into seven groups having 10 animals in each group. Group numbers 1 to 7 were named as pregnant heifers, pregnant lactating cows, non-pregnant dry cows, non-pregnant heifers, parturient cows, pregnant dry cows and non-pregnant lactating cows, respectively. Blood samples from all the animals were collected and haematological values were recorded, using routine haematological procedures. The highest Hb concentration (11.32 ± 0.32 gm/dl) was recorded in group-4, while the lowest (9.24 ± 0.35 gm/dl) was observed in group-7. The highest RBCs count and PCV (6.18 ± 0.47 x 106/μl and 35.51 ± 1.51%) were recorded in group-4 and the lowest (4.55 ± 0.26 x 106/μl and 29.23 ± 1.09%) values were observed in group-6. The highest MCV, MCH and MCHC (65.26 ± 1.96 fl, 23.50 ± 1.31 pg and 35.75 ± 0.99 gm/dl) were noted in group-5 and the lowest (55.16 ± 1.72 fl, 16.77 ± 1.14 pg and 30.09 ± 1.15 gm/dl) were noted in group-2. The highest ESR (7.60 ± 1.15 mm/24 hours) was recorded in group-6 and the lowest (4.89 ± 0.40 mm/24 hours) values were observed in group-5. The highest WBCs count (9.43 ± 1.15 x 103/μl) was observed in group-1 and the lowest (6.35 ± 0.72 x 103/μl) was recorded in group-5. Amongst DLC, highest (P<0.05) lymphocyte count (69.10 ± 2.55%) was observed in group-4, while lowest count (56.70 ± 5.16%) was in group-5. The differences between monocyte, neutrophil, eosinophil and basophil counts in all the groups were statistically non-significant.
Serum calcium and magnesium level in dairy cows at calving  [cached]
F. Masoero,M. Moschini,A.M. Pulimeno
Italian Journal of Animal Science , 2011, DOI: 10.4081/ijas.2003.s1.172
Abstract: Milk fever and hypocalcaemia are post-partum metabolic diseases affecting about 6% of dairy cows and are due to a fail of the homeostatic metabolism regulating the calcium blood level around 9 and 10mg/100mL. The calcium drainage to the mammary gland along with the reduced capacity of the animal to mobilize calcium from bone reserve lead to a drop of the calcium blood level under 5-6mg/100mL with paresis like clinical symptoms known as milk fever. The incidence of the clinical milk fever is low, however the occurrence of mild hypocalcaemia (subclinical) could be as high as 15- 20% within few days after calving, particularly in multiparous cows. The hypocalcaemia status as for the reduced bone calcium mobilization and intestinal absorption leads to reduced feed intake and make it a good start for ketosis, retained placenta, displaced abomasums and mastitis problems (Beede, 1991). The acid-base balance of the cow in the late pregnancy is determinant for hypocalcaemia............
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