Δ9 -desaturase activity in the mammary gland of lactating dairy cows

2002 ◽  
Vol 2002 ◽  
pp. 181-181
Author(s):  
A.L. Lock ◽  
P.C. Garnsworthy
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Mammary Gland ◽  
Dairy Cows ◽  
Milk Fat ◽  
Desaturase Activity ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Lactating Dairy Cows ◽  
Δ9 Desaturase

The Δ9 -desaturase system (steroyl-CoA desaturase) involves the addition of a cis double bond between carbons 9 and 10 of fatty acids. The conversion of stearic acid (C18:0) to oleic acid (cis-9 C18:1) is the predominant precursor:product of this enzyme system; conversion of saturated fatty acids (SFA) to mono-unsaturated fatty acids (MUFA) is important in determining the fluidity of milk. In previous studies (Lock & Garnsworthy 2001), we have shown that more than 50% of the oleic acid occurring in milk is produced in the mammary gland via Δ9 -desaturase. We also found that the conversion of trans-11 C18:1 to cis-9, trans-11 conjugated linoleic acid (CLA) accounted for ~80% of milk fat CLA. Increasing the activity of Δ9 -desaturase offers the opportunity of increasing the MUFA content of milk, especially oleic acid, while decreasing its SFA content, as well as increasing the CLA content of milk. Lock & Garnsworthy, (2001) also reported that there were significant differences between individual cows with regard to milk fat CLA content. In an earlier study (Lock & Garnsworthy, 2000) we found that the CLA content of milk varied throughout the year, with highest values occurring when cows received fresh pasture. In view of the significant contribution of Δ9 -desaturase to the CLA and MUFA content of milk, the objective of the work reported here was to investigate individual animal and dietary variation in Δ9 -desaturase activity in the mammary gland of lactating dairy cows.

scholarly journals Identification of circRNA-Associated-ceRNA Networks Involved in Milk Fat Metabolism under Heat Stress

2020 ◽  
Vol 21 (11) ◽  
pp. 4162
Author(s):  
Dongyang Wang ◽  
Zujing Chen ◽  
Xiaona Zhuang ◽  
Junyi Luo ◽  
Ting Chen ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Heat Stress ◽  
Mammary Gland ◽  
Dairy Cows ◽  
Milk Fat ◽  
Unsaturated Fatty Acids ◽  
Negative Impact ◽  
Biological Activities ◽  
Fat Metabolism ◽  
Milk Quality

Summer temperatures are generally high in Southern China, and cows are likely to suffer a heat stress reaction. Heat stress will have a negative impact on the performance of dairy cows; however, the mechanism by which high temperature affects lactation is not clear. CircRNA is a type of non-coding RNA discovered in recent years, which performs a crucial function in many biological activities. However, the effects of circRNA on lactation function of dairy cows under heat stress is unknown. The present study aimed to explore the expression levels of circRNA in the mammary gland tissue of cows under heat stress. Firstly, we collected blood and milk samples of summer and winter cows and evaluated lactation performance using serum indicators, milk production, and milk composition. Incorporating the calculation of the temperature and humidity index, we conformed the heat stress status of cows in summer. Heat stress increased the concentration of HSP70 and decreased the concentration of SOD and PRL. Heat stress not only reduced milk yield but also affected milk quality, with milk lactose and milk protein decreasing with increased temperature. The analysis of the fatty acid composition in summer milk found significantly reduced concentrations of unsaturated fatty acids, especially long-chain unsaturated fatty acids. Sequencing of the cow’s mammary gland transcriptome revealed that compared to the appropriate temperature (ST) group, the heat stress (HS) group had a total of 2204 upregulated and 3501 downregulated transcripts. GO enrichment and KEGG pathway analysis showed that these genes were mainly related to milk fat metabolism. In addition, 19 upregulated and 19 downregulated circRNA candidates were found in response to heat stress. We used Pearson’s test to establish the correlation of circRNA-mRNA and identified four pairs of circRNA-miRNA networks between four circRNAs, six miRNAs, and the CD36 gene. In this study, we revealed the possible role of circRNAs in lactation of dairy cows and identified that circRNA-miRNA-mRNA networks might exist in the cow’s mammary glands, providing valuable experience for dairy lactation and milk quality.

scholarly journals Dietary unsaturated fatty acids affect the mammary gland integrity and health in lactating dairy cows

2011 ◽  
Vol 5 (S4) ◽  
Author(s):  
Núria Mach ◽  
Jürgen van Baal ◽  
Leo Kruijt ◽  
Antoon Jacobs ◽  
Mari Smits
Keyword(s):  
Fatty Acids ◽  
Mammary Gland ◽  
Dairy Cows ◽  
Unsaturated Fatty Acids ◽  
Lactating Dairy Cows

scholarly journals Effect of Feefing Protected Lipid on the Uptake of Precursors of Milk Fat by the Bovine Mammary Gland

1973 ◽  
Vol 26 (5) ◽  
pp. 1201 ◽  
Author(s):  
JM Gooden ◽  
AK Lascelles
Keyword(s):  
Fatty Acids ◽  
Mammary Gland ◽  
Fatty Acid ◽  
Dairy Cows ◽  
Milk Fat ◽  
Bovine Mammary Gland ◽  
Lactating Dairy Cows

The feeding of protected lipid to lactating dairy cows resulted in a substantial increase in the proportion of fatty acid 18:2 and a decrease in fatty acids 4:0 to 16:0 in milk fat.

scholarly journals Influence of the Type of Silage in the Dairy Cow Ration, with or without Grazing, on the Fatty Acid and Antioxidant Profiles of Milk

Dairy ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 716-728
Author(s):  
Senén De La Torre-Santos ◽  
Luis J. Royo ◽  
Adela Martínez-Fernández ◽  
Mario Menéndez-Miranda ◽  
Rocío Rosa-García ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Dairy Cows ◽  
Milk Production ◽  
Faba Bean ◽  
Milk Fat ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Italian Ryegrass ◽  
Feeding System ◽  
Self Sufficiency

Dairy systems based on grass and forages are widely spread throughout the European Atlantic Arc and they have an influence on milk quality. Likewise, legumes are a key element in the farms to improve cows’ diet and farm feed self-sufficiency. The aim of this study was to evaluate the effect of the legumes in the diet and the feeding system (pasture-based vs. confined) on milk production and composition. An assay was performed with 18 Friesian cows randomized into two management groups (grazing or confined). Three total mixed rations based on Italian ryegrass, faba bean or field pea silages were offered ad libitum for nine continuously housed cows or during two hours after each milking for another nine grazing cows. Regardless of type of silage, grazing cows had higher dry matter intake and milk production than confined cows. Likewise, grazing cows produced milk with a lower concentration of protein and urea than confined cows. The dairy cows fed total mixed rations based on both legume silages had a milk fat with a higher proportion of unsaturated fatty acids, especially with the inclusion of faba bean silage in the diet. The results demonstrate that the profile of fatty acids and antioxidants is related to the feeding system in dairy cows. Grazing directly influenced the composition of milk, decreasing the proportion of saturated fatty acids and increasing the content of unsaturated fatty acids, as CLA, and the antioxidants, as lutein and β-cryptoxanthin.

Estimation of genetic variation in A9-desaturase enzyme activity in dairy cows

2005 ◽  
Vol 2005 ◽  
pp. 52-52 ◽  
Author(s):  
M.D. Royal ◽  
P.C. Garnsworthy
Keyword(s):  
Genetic Variation ◽  
Oleic Acid ◽  
Mammary Gland ◽  
Dairy Cows ◽  
Desaturase Activity ◽  
Vaccenic Acid ◽  
Mammary Tissue ◽  
Milk Fatty Acid ◽  
Fatty Acid Profiles ◽  
Δ9 Desaturase

The ▵9-desaturase enzyme adds a cis-9 double bond to fatty acids in adipose and mammary tissue. In the mammary gland, this reaction converts C14:0 to C14:1, C16:0 to C16:1, C18:0 to cis-9 C18:1 (oleic acid), and trans- 11 C18:1(vaccenic acid) to cis-9, trans- 11 conjugated linoleic acid (CLA). Oleic acid is of interest in human nutrition as a component of the “Mediterranean diet” and CLA has been shown to have numerous health benefits. Conversion of vaccenic acid to CLA in the mammary gland accounts for 75-80% of CLA found in milk (Lock and Garnsworthy, 2002), but activity of the Δ9-desaturase enzyme varies among individual cows irrespective of dietary manipulations (Lock and Garnsworthy, 2003), suggesting that it may have a genetic component. The objective of this study was to estimate the genetic variation in Δ9-desaturase activity in dairy cows using milk fatty acid profiles.

scholarly journals Influence of Dietary Fish Oil on Conjugated Linoleic Acid and Other Fatty Acids in Milk Fat from Lactating Dairy Cows

2000 ◽  
Vol 83 (11) ◽  
pp. 2620-2628 ◽  
Author(s):  
D.C. Donovan ◽  
D.J. Schingoethe ◽  
R.J. Baer ◽  
J. Ryali ◽  
A.R. Hippen ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Linoleic Acid ◽  
Fish Oil ◽  
Dairy Cows ◽  
Conjugated Linoleic Acid ◽  
Milk Fat ◽  
Lactating Dairy Cows ◽  
Dietary Fish

scholarly journals Daytime Grazing in Mountainous Areas Increases Unsaturated Fatty Acids and Decreases Cortisol in the Milk of Holstein Dairy Cows

Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3122
Author(s):  
Jalil Ghassemi Nejad ◽  
Bae-Hun Lee ◽  
Ji-Yung Kim ◽  
Kyung-Il Sung ◽  
Hong-Gu Lee
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Dairy Cows ◽  
Milk Fat ◽  
Unsaturated Fatty Acids ◽  
Control Group ◽  
Milk Fatty Acid ◽  
Omega 3 ◽  
Mountainous Areas ◽  
Lactating Cows

The effects of grazing lactating cows in mountainous areas for 12 and 24 h compared with the confined indoor system were evaluated by examining the overall milk fatty acid and cortisol. Twenty-one dairy cows were allocated to three treatment groups: (1) control (confined management system in a free-stall barn; TMR based), (2) grazing for 12 h (12hG; TMR plus grazing pasture), and (3) grazing for 24 h (24hG; pasture-based feeding system). Dry matter intake was higher in the control and 12hG groups than in the 24hG group. The yields of total milk and the 3.5% fat-corrected milk were the lowest in the 24hG group. Milk fat was the highest in the 24hG group and higher in 12hG compared with the control group. Milk protein and lactose levels were the highest in the 12hG group. The highest somatic cell count was observed in the 24hG group. The saturated fatty acid levels were higher in the control group compared with the 12hG and 24hG groups. There was no difference in overall mono-unsaturated fatty acids between 12hG and 24hG groups. Poly-unsaturated fatty acids were higher in the 12hG group compared with the control and 24hG groups. There was no difference in omega-6 (ω-6) fatty acids among the groups, and omega-3 fatty acids were higher in the 12hG group than in the control group. Milk cortisol was the highest in the 24hG group and higher in the control group compared with the 12hG group. Taken together, grazing for 12 h is advisable for farms that have access to mountainous areas to improve the milk fatty acid profile and decrease the stress levels in high-yielding Holstein lactating cows.

scholarly journals Effect of nitrogen and potassium fertilization on the production and quality of oil in Jatropha curcas L. under the dry and warm climate conditions of Colombia

2014 ◽  
Vol 32 (2) ◽  
pp. 255-265 ◽  
Author(s):  
Omar Montenegro R. ◽  
Stanislav Magnitskiy ◽  
Martha C. Henao T.
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Jatropha Curcas ◽  
Oil Content ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Fruit Production ◽  
Biodiesel Production ◽  
Oil Composition

This study was conducted to assess fruit and seed yield, oil content and oil composition of Jatropha curcas fertilized with different doses of nitrogen and potassium in Espinal (Tolima, Colombia). The yields ranged from 4,570 to 8,800 kg ha-1 of fruits and from 2,430 to 4,746 kg ha-1 of seeds. These yields showed that the fertilizer dose of 150 kg ha-1 N + 120 kg ha-1K increased fruit production by 92% and seed production by 95%, which represents an increase of about 100% in oil production, which increased from 947 to 1,900 kg ha-1. The total oil content in the seeds ranged from 38.7 to 40.1% (w/w) with a high content of the unsaturated fatty acids oleic (> 47%) and linoleic acid (> 29%). The highest content of oleic acid in the seed oil was from the unfertilized control plants and plants with an application of 100 kg ha-1 of N and 60 kg ha-1 of K, with an average of 48%. The lowest content of oleic acid was registered when a low dose of nitrogen and a high level of potassium were applied at a ratio of 1:2.4 and doses of 50 kg ha-1 N + 120 kg ha-1 K, respectively. Low contents of the saturated fatty acids palmitic (13.4%) and stearic (7.26%) were obtained, making this oil suitable for biodiesel production. The nitrogen was a more important nutrient for the production and quality of oil in J. curcas than potassium under the studied conditions of soil and climate.

scholarly journals Addition of unsaturated fatty acids improves digestion of mid lactating dairy cows

2014 ◽  
Vol 63 (244) ◽  
pp. 563-573 ◽  
Author(s):  
J.E. Freitas Júnior ◽  
F.P. Rennó ◽  
J.R. Gandra ◽  
L.N. Rennó ◽  
A.C. Rego ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Dairy Cows ◽  
Unsaturated Fatty Acids ◽  
Lactating Dairy Cows
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