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หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Clinical-biochemical Observations in Periparturient Dairy Cows with Experimentally Induced Fatty Liver) ผู้เขียน:ดร.ธีระ รักความสุข, รองศาสตราจารย์, Theo Wensing, Henk J. Breukink สื่อสิ่งพิมพ์:pdf AbstractIn 4 experimental studies, occurrences of health problems during the first 4 weeks of lactation were monitored in 36 control cows and 38 experimental cows that were overfed during the dry period to induce overconditioning at calving and deep negative energy balance and fatty liver postpartum. The experimental cows experienced postparturient problems, including milk fever (37%), acetonemia (8%), abomasal displacement (8%), mastitis (10%), and hoof problems (8%). Acetonemia and abomasal displacement were not observed in the control cows. Milk fever, mastitis, and hoof problems were observed in 3%, 6% and 3% of the control cows, respectively. The experimental cows gained more body weights during the dry period and lost more weights during the first 4 or 5 weeks of lactation than did the control cows. Between 1 and 2 weeks after parturition, the experimental cows had higher concentrations of blood nonesterified fatty acids, blood 3-hydroxybutyrate, and liver triacylglycerols, and had lower concentrations of liver glycogen than did the control cows. Blood glucose and insulin concentrations did not differ between the two groups. When data of the 4 studies were pooled, blood nonesterified fatty acid concentrations were positively correlated with blood 3-hydroxybutyrate and liver triacylglycerol concentrations, and were negatively correlated with liver glycogen concentrations. These results indicated that cows responded to a marked increase in energy requirements in early lactation by increased glycogenolysis in the liver and lipolysis in adipose tissue. In conclusion, overfeeding of cows during the dry period resulted in overcondition at calving. Overconditioning predisposed a cow to develop severe fatty liver postpartum and to experience more postparturient problems. The concentration of blood nonesterified fatty acids postpartum could be used as a routine indicator for the development of fatty liver in dairy cows postpartum. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Performance of Periparturient Dairy Cows Fed Alfalfa Hay in Total Mixed Ration : A Field Trial in Thailand) ผู้เขียน:ดร.ธีระ รักความสุข, รองศาสตราจารย์, Sunthorn Rungruang2,, ดร.อาภัสสรา ชูเทศะ, รองศาสตราจารย์, Theo Wensing สื่อสิ่งพิมพ์:pdf AbstractPerformance of 20 periparturient Holstein Friesian dairy cows fed alfalfa hay-base total mixed
rations during transition and lactation periods was studied in a commercial dairy farm. From 7 d prior to
anticipated calving date until 7 d after calving, all cows were also drenched with 400 ml of propylene
glycol once daily. Blood samples were collected at -2, 1, 2, 3 and 4 wk from parturition. Milk yields
were recorded daily, and milk samples were collected twice a week to determine milk compositions.
Compared with the concentrations at -2 wk, serum glucose and urea nitrogen concentrations decreased
whereas serum non-esterified fatty acid and ?-hydroxybutyrate concentrations increased after calving.
These results indicated that these cows entered some degrees of negative energy balance. Average milk
production during 30 d postpartum was 34.8 ? 8.7 kg/d. Average days from calving to first service was
86 ? 24 d, and 55% of 20 cows were conceived at first service. In conclusion, cows fed alfalfa hay-base
diet and drenched with propylene glycol during periparturient period could improve negative energy
balance, milk yield and conception rate. However, replacing roughages from agro-industry by product
with alfalfa hay in Thai dairy farms would depend on the economical analysis because most alfalfa hay
was imported from foreign country. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Fatty Liver in High Producing Dairy Cows Kept in Evaporative Cooling System in a Commercial Dairy Herd in Thailand) ผู้เขียน:ดร.ธีระ รักความสุข, รองศาสตราจารย์, Sunthorn Rungruang, Theo Wensing สื่อสิ่งพิมพ์:pdf AbstractThe occurrence of fatty liver was investigated in a commercial dairy farm under evaporative cooling system in Thailand by determination of triacylglycerol concentrations in the liver. Nineteen Holstein-Friesian cows were used. Liver samples were collected at -2, 1, 2, 3, and 4 wk from parturition. At -2 wk, mean liver triacylglycerol concentration was 24.3 ? 1.0 mg/g of liver. After parturition, mean liver triacylglycerol concentration from 6 cows was lower than 50 mg/g of liver (mild fatty liver group), the mean concentration from 8 cows was between 50 and 100 mg/g of liver (moderate fatty liver group), and the mean concentration from 5 cows was greater than 100 mg/g of liver (severe fatty liver group). The results showed that 68.4% of dairy cows in this investigation suffered from periparturient fatty liver. Milk production in severe fatty liver group tended to be higher than the milk production in mild or moderate fatty liver cows. This result indicated that cows with higher milk yield tended to enter deeper negative energy balance postpartum and as a consequence had more intensive lipolysis, leading to accumulation of a greater amount of triacylglycerols in the liver. In conclusion, an evidence of fatty liver was found in high producing dairy cows, kept under cooled condition in Thailand. Before any preventive measures could be made, further research is required to study the effect of fatty liver or negative energy balance on periparturient problems, i.e. infertility, metabolic disorders, in dairy cows raised in Thai conditions. |
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