Ingestion of medium chain fatty acids by lactating dairy cows increases concentrations of plasma ghrelin

The purpose of this study was to elucidate the effects of medium-chain fatty acids (MCFAs) on plasma ghrelin concentration in lactating dairy cows. Five early-lactating Holstein cows were randomly assigned to 2 dietary treatments in a crossover design with 2-wk periods. Treatments consisted of diets supplemented or not (control) with calcium salts of MCFAs (MCFA-Ca; 1.5% dry matter). Plasma hormone and metabolite concentrations in blood samples taken from the jugular vein were measured on the morning of feeding on day 14 of each period. Dry matter intake, milk protein, and lactose content of cows fed the MCFA-Ca diet were decreased compared with controls, but with no change in milk yield. Plasma ghrelin concentrations were higher in cows fed the MCFA-Ca diet; however, no significant effect was found on glucagon-like peptide-1 concentrations in plasma. Plasma insulin concentrations decreased, but plasma glucagon concentrations remained unchanged in cows fed the MCFA-Ca diet. The concentrations of nonesterified FAs, total cholesterol, and β-hydroxybutyrate in plasma increased in these cows. In conclusion, dietary MCFAs increase the plasma ghrelin concentrations in lactating dairy cows.     

Variations in parameters of liver function and plasma progesterone related to underfeeding and ketosis in a dairy herd

Twenty-eight Norwegian Red Cattle dairy cows were fed silage ad libitum and restricted amounts of concentrates. Blood samples were collected before morning feeding, once or twice weekly, from 2 weeks before to 12 weeks after calving. Parameters of liver function, carbohydrate status and fertility were recorded in order to assess their interrelationships. Eight cows were treated for clinical ketosis. Four of these had to be treated 2 or 3 times. Aspartate aminotransferase and bilirubin showed the highest within-animal coefficients of correlation with acetoacetate. Analysis of variance revealed a significant effect of carbohydrate status (indicated by plasma acetoacetate levels) on the levels of aspartate aminotransferase, glutamate dehydrogenase and sorbitol dehydrogenase, though only a small part of the total variation was explained by this factor. The estimated volume density of liver fat in the 4th week of lactation averaged 6.0 +/- 6.4% (+/- SD) ranging from 0.1-25.1%. Liver fat content at this stage of lactation was not significantly correlated with other indicators of liver function or carbohydrate status. Cows treated for clinical ketosis had significantly lower plasma progesterone values at the time of first ketosis treatment than untreated multiparous cows. The frequency of high progesterone values (greater than 3 ng/ml) being significantly lower in treated than in untreated cows during the period from 3-5 weeks post partum, though not at later stages. In conclusion, the results revealed a significant relationship between carbohydrate status and liver function, and also between clinical ketosis and luteal function.     

Plasma lipids in normal cows around partus and in cows with metabolic disorders with and without fatty liver

Free fatty acids, cholesterol and phospholipids in plasma were studied from 6 weeks before to 6 weeks after calving in 16 normal multiparous cows. The same plasma lipids were studied the day after calving in 20 normal primiparous cows. Ten of these were fed according to standards and the other 10 were overfed the last 3 weeks prepartum. The plasma lipids were also analysed in 16 cows with left displacement of the abomasum and fatty liver, and in 16 cows with ketosis with no or only slight fat infiltration of the liver. In the normal cows there was a rise in FFA-level and a reduction in cholesterol and phospholipids from 6 weeks before to the day after calving. Thereafter there was a reduction of FFA-level and rise in cholesterol and phospholipids. Increased feed intensity had no effect on plasma lipids at calving. The level of the plasma lipids in cows with fatty liver differed very much from the amounts in normal cows at corresponding time from calving. Cows with ketosis had high FFA-level but the amount of cholesterol and phospholipids differed very little from normal cows.     

A Comparison of the Plasma Fructose Concentrations in Dogs and Cats and Changes in the Fructose Concentrations in Dogs Following Intravenous Administration of Fructose

The plasma concentrations of fructose, glucose, free fatty acids (FFA) and triglycerides (TG) were measured in dogs and cats. Changes in these concentrations were investigated in dogs by an intravenous fructose tolerance test (IVFTT) at a dose of 0.1 g/kg body weight. Fructose concentrations in the plasma of dogs were significantly higher than those of cats. There was no significant difference in plasma glucose concentrations between dogs and cats. Plasma FFA concentrations decreased and TG concentrations increased after feeding in both dogs and cats. During the IVFTT, the plasma fructose concentrations in the dogs increased rapidly to a peak by 2 min and then decreased to half of the peak by 5 min after the administration of fructose. Administration of fructose resulted in an increase in the plasma TG concentrations and reduced plasma FFA concentrations in the dogs. Only 4% of the administered fructose was detected in the urine of dogs following IVFTT. Plasma fructose was considered to be rapidly absorbed and metabolized in both dogs and cats. However, as with glucose metabolism, there appear to be some differences in fructose metabolism between dogs and cats.     

Changes in the serum levels of primary bile acids in dairy cows

Serum cholic acid (SCA) and serum chenodeoxycholic acid (SCDCA) concentrations were determined in healthy dairy cows by radioimmunoassay (RIA). The levels of these two primary bile acids were correlated with the cows' reproductive status. The lowest concentrations were measured in dry cows (SCA: 7.8 +/- 3.3 mumol/l, SCDCA.: 1.5 +/- 1.0 mumol/l). In freshly calved cows SCA and SCDCA was 17.8 +/- 6.9 mumol/l and 2.3 +/- 1.0 mumol/l, respectively, while in milking cows SCA and SCDCA was 15.8 +/- 5.7 and 2.3 +/- 0.8 mumol/l, respectively. SCA concentration showed a characteristic change on the days immediately after calving: on calving day it was close to the mean SCA concentration found for dry cows, then it underwent a striking abrupt rise and reached the value typical of post-parturient cows by post-partum (PP) day 4-5. Cholic acid was found to be the major primary bile acid in the blood of dairy cows. In dry cows the SCA:SCDCA ratio is 5:1. If the serum bile acid concentration rises, the SCA:SCDCA ratio will increase further.     

Effect of extruded linseed on productive and reproductive performance of lactating dairy cows

A total of 356 early lactation multiparous Holstein cows were used in a randomized complete block design to determine the effects of feeding extruded linseed on milk production and composition, and reproductive performance. Forty of these cows were randomly selected to study the effects of extruded linseed on milk fatty acid (FA) profile, individual feed intake and prostaglandin secretion. Cows were fed a 40:60 forage to concentrate ratio diet (17.9% CP, 27.7% NDF and 6.0% EE) ad libitum that was similar in composition between treatments except for the protein supplements that differed and were control (CTR: 4.9% extruded soybean) and linseed (LIN: 5.5% extruded linseed). Individual DM intake measured at 40 (23.0 kg/d) and 90 (24.2 kg/d) days in milk, and milk yield (45.0 kg/d) were not affected by treatment, but the lower (P < 0.05) milk fat percentage in cows fed LIN (2.65%) compared with CTR (2.86%) resulted in lower (P < 0.05) 4.0% fat-corrected milk yield for cows fed LIN (35.4 kg/d) compared with CTR (37.7 kg/d). Milk protein content was higher (P < 0.05) in LIN (3.04%) than in CTR (3.00%). The concentration of saturated FA was lower (P < 0.05) in milk fat from LIN (56.2%) compared with CTR (60.2%). Monounsaturated FA (35.7 vs. 32.7%) and polyunsaturated FA (8.0 vs. 6.9%) were higher in LIN (P < 0.05) than in CTR. Supplementation with LIN also increased (P < 0.05) the proportion of vaccenic acid (2.21 vs. 1.55%), total conjugated linoleic acid (0.91 vs. 0.72%) and n-3 FA (1.21 vs. 0.54%) in milk compared with CTR. Plasma concentrations of prostaglandin metabolite were numerically lower in LIN (106 pg/ml) compared with CTR (120 pg/ml) (P = 0.16) but reproductive performance was similar between treatments. In summary, extruded linseed reduced milk fat percentage and 4.0% fat-corrected milk yield and increased milk protein percentage and the content of healthy FA in milk without modifying DM intake, milk yield and reproductive performance.     

Effect of dietary fish oil on milk yield, fatty acids content and serum metabolic profile in dairy cows

The aim of the study was to evaluate the effects of dietary unprotected fish oil on milk yield, fatty acids content and serum metabolic profile in dairy cows. Forty lactating Polish Holstein-Friesian cows were assigned to two groups. The cows were fed a control basal diet (C group), or a basal diet containing 2% addition of fish oil on mineral carrier (FOM group) during a 8-week period. Supplementing FOM diet of dairy cows had no significant effect on milk fat, milk protein, milk lactose concentration and somatic cells count, but increased the milk yield (36.5 kg/d), (p < 0.05) compared with the control cows (34.28 kg/d). We observed an increase (p < 0.05) in body condition scoring between C and FOM groups. Additionally, higher levels of non-esterified fatty acids and β-hydroxybutyrate acid were noticed in FOM group after 8 weeks of the experiment; however, these serum parameters still were in the reference range. Concentration of insulin was higher (30.40 μU/ml; p < 0.01) in the FOM group compared with the control group (14.03 μU/ml). In the FOM group, significant increase (p < 0.01) in long-chain fatty acids, mainly cis-9, trans-11 CLA and n-3 fatty acids (eicosapentaenoic and docosahexaenoic acids) was observed. The obtained results demonstrated that addition of fish oil to cows' diet could profitably modify the fatty acids in cow's milk.     

Relationship between overfeeding and overconditioning in the dry period and the problems of high producing dairy cows during the postparturient period

Summary

In dairy cows, overfeeding during the dry period leads to overcondition at calving and to depression of appetite after calving. As a consequence, at calving overconditioned high‐producing dairy cows inevitably go into a more severe negative energy balance (NEB) postpartum than cows that have a normal appetite. During the period of NEB, the energy requirements of the cow are satisfied by lipolysis and proteolysis. Lipolysis results in an increased concentration of non esterified fatty acids (NEFA) in the blood. In the liver, these NEFA are predominantly esterified to triacylglycerols (TAG) that are secreted in very low density lipoproteins (VLDL). In early lactation in cows with a severe NEB, the capacity of the liver to maintain the export of the TAG in the form of VLDL in balance with the hepatic TAG production is not always adequate. As a result, the excess amount of TAG accumulates in the liver, leading to fatty infiltration of the liver (hepatic lipidosis or fatty liver). The NEB and/or fatty liver postpartum are frequently associated with postparturient problems. In general, a severe NEB induces changes in biochemical, endocrinological, and metabolic pathways that are responsible for production, maintenance of health, and reproduction of the postparturient dairy cow. These changes include a decrease in blood glucose and insulin concentrations, and an increase in blood NEFA concentrations. High NEFA concentrations caused by intensive lipolysis are accompanied by impairment of the immune system, making the cows more vulnerable to infections. Metabolic diseases such as ketosis, milk fever, and displaced abomasum are related to overcondition at calving. The changes in biochemical, endocrinological, and metabolic pathways are associated with delay of the first visible signs of oestrus, an increase in the interval from calving to first ovulation, a decrease in conception rate, and a prolonged calving interval. It is possible that the increased blood NEFA concentration directly impairs ovarian function.     

Effect of nicotinic acid on the plasma membrane function and polyunsaturated fatty acids composition during cryopreservation in boar sperm

This study was conducted to evaluate the effect of nicotinic acid on plasma membrane integrity and fatty acid composition in frozen–thawed boar sperm. Boar semen was cryopreserved using freezing extender containing nicotinic acid (NA), then plasma membrane integrity, osmotic equilibration, lipid peroxidation and fatty acid were analysed. The plasma membrane integrity of frozen–thawed sperm was significantly higher in the 10 mM NA than in the 0 and 20 mM NA treatment groups (p < 0.05). Additionally, the osmotic equilibration ability was not different in treatment groups, but lipid peroxidation was significantly decreased in the 10 mM NA treatment group (p < 0.05). The saturated fatty acids were significantly decreased in the 10 mM NA treatment group, and C18:1n‐9, C18:2n‐6, C20:4n‐6, C22:5n‐6 and C22:6n‐3, and total polyunsaturated fatty acids (PUFAs) were significantly increased in the 10 mM NA treatment groups (p < 0.05). In summary, 10 mM NA improved plasma membrane integrity, inhibited lipid peroxidation and increased PUFAs in frozen–thawed boar sperm. These results suggest that NA may be useful to protect the plasma membrane and inhibit the loss of PUFAs for sperm cryopreservation in pigs.     

Changes in plasma bile acids,plasma amino acids,and hepatic enzyme pools as indices of functional impairment in liver-damaged sheep

Plasma bile acids, plasma amino acids, and the total hepatic pools of aspartate aminotransferase, gamma glutamyltransferase, glutamate dehydrogenase, and sorbitol dehydrogenase were compared in control sheep (Group 1), sheep with subclinical pyrrolizidine alkaloid toxicosis (Group 2), and in sheep with acute hepatocellular necrosis associated with the hemolytic phase of chronic copper poisoning (Group 3). Subclinical pyrrolizidine alkaloid toxicosis was not associated with any changes in bile acid or amino acid status but was associated with a significant decline in the hepatic pools of sorbitol dehydrogenase and aspartate aminotransferase. This observation could not be explained in terms of enzyme leakage from damaged hepatocytes and suggested that pyrrolizidine alkaloids might specifically inhibit hepatocellular enzyme synthesis. Group 3 sheep also had reduced hepatic enzyme pools which were at least partly referable to enzyme leakage from damaged hepatocytes. In these sheep, increases in plasma bile acids were a more sensitive index of hepatic function than were either increased aromatic amino acid concentration or the ratio between branched chain and aromatic amino acids.     

Transport of fatty acids within plasma lipoproteins in lactating and non‐lactating cows fed on fish oil and hydrogenated palm oil

The aim of this study was to elucidate the effect of dietary fish oil (FO) and a blend of FO and hydrogenated palm oil (FOPO) on transport of fatty acids (FA) within plasma lipoproteins in lactating and non‐lactating cows. Two trials were conducted (one with lactating and another with non‐lactating dairy cows) in two 3 × 3 Latin squares that included three periods of 21 days. Dietary treatments for lactating cows consisted of a basal diet (Control; no fat supplement), and fat‐supplemented diets containing FO (500 g/day/cow) and FOPO (250 FO + 250 g/day/cow hydrogenated palm oil). For non‐lactating cows, dietary treatments consisted of a basal diet (Control; no fat supplement), and fat‐supplemented diets containing FO (170 g/day/cow) and FOPO (85 FO + 85 hydrogenated palm oil g/day/cow). In lactating cows, compared with control and FOPO, FO increased C16:0, C18:3 cis‐9, 12, 15, C18:2 cis‐9, trans‐11 and total saturated and polyunsaturated FA in plasma and increased C16:0, C18:2 cis‐9, trans‐11, total polyunsaturated and total polyunsaturated n‐6 in high‐density lipoprotein (HDL), whereas in non‐lactating cows, compared with control and FOPO, FO increased C16:0, C18:1 trans‐11, C18:2 trans‐9, 12, C18:2 cis‐9, trans‐11, C20:5 n‐3 and total saturated and polyunsaturated FA in plasma; C16:0, C18:1 trans‐11, C18:1 cis‐9, C18:2 trans‐9, 12, C20:5 n‐3 and total monounsaturated FA in HDL; and C18:1 trans‐6‐8, C18:1 trans‐9, C18:1 trans‐10, C18:1 trans‐11, C18:3 cis‐9, 12, 15 and C20:5 n‐3 in low‐density lipoprotein (LDL). FO increased C20:5 n‐3 in plasma and lipoproteins in non‐lactating cows and increased C18:3 cis‐9, 12, 15 in plasma (in lactating cows) and LDL (in non‐lactating cows). We concluded from results of this study that in bovine plasma, the LDL fraction appears to be the main lipoprotein transporting C18:1 trans isomers and is more responsive than other lipoprotein fractions to variation in supply of dietary lipids.     

Diurnal variation and the effect of feed restriction on plasma and milk metabolites in TMR-fed dairy cows

The objective was to study the diurnal variation in metabolites in plasma and milk of dairy cows fed total mixed rations (TMR) with a low-energy (LE) or high-energy content (HE) expected to give a minor and a major diurnal variation, respectively. Further, the purpose was to quantify and compare the responses in plasma and milk parameters when cows changed from ad libitum to restrictive feeding. Eight multiparous, early-lactating Danish Holstein cows were used in a cross-over design with two consecutive 14-day periods. Blood and milk samples were collected hourly on day 11 of each period and on days 12-14 of each period, the cows were fed restrictively (65% of ad libitum dry-matter intake). The concentration of beta-hydroxybutyrate (BHB) in plasma was significantly higher in the evening for cows fed the HE TMR, than for cows fed the LE TMR. There was a significant diurnal variation in BHB in milk, with the highest concentrations between milkings and the lowest concentrations at milking. Non-esterified fatty acids (NEFA) in plasma showed significant diurnal variation that was caused by high concentrations in the morning. Plasma glucose did not show any diurnal variation. It has been argued that feeding a TMR removes diurnal changes related to feeding, which is contrary to earlier diurnal studies where concentrates have been fed twice daily. Feed restriction increased (P < 0.001) NEFA and BHB in plasma by 121 and 90%, respectively, while the glucose concentration decreased (P < 0.001) by 19%. Milk concentrations of BHB, citrate and fat increased (P < 0.001) by 163, 11 and 26%, respectively, because of feed restriction, while there were no changes in milk protein and lactose. The relatively high increase in BHB during feed restriction suggests that BHB is more advantageous as a milk indicator of metabolic status in dairy cows than citrate and fat.     

Evaluation of biochemical profile of dairy cows with metabolic diseases in tropical conditions

The aims of this study were to characterize the biochemical profile, the reproductive performance and to identify potential predictive biomarkers of disease state of dairy cows with hyperketonemia, lipomobilization and hypocalcemia raised in tropical conditions in southeastern Brazil. Dairy cows (n = 50) were divided into a group of healthy cows (n = 14), cows with lipomobilization (n = 14), cows with hypocalcemia (n = 11), and a group of cows with hyperketonemia (n = 11). Evaluation of body condition score (BCS), body weight (BW) and blood samples was performed on 21, 14, 7, 4 and 2 days before calving, parturition, 1, 7, 14, 21, 30, 45 and 60 days post-partum and milk production was recorded on days 7, 14, 21, 30, 45 and 60 after parturition. Blood samples were assayed for aspartate aminotransferase (AST), gamma-glutammyltransferase (GGT), albumin, total protein, globulin, fibrinogen, total cholesterol, triglyceride, urea and creatinine concentrations. The biochemical profile, BCS, BW, milk production and reproductive performance differed (p < .05) among the groups. Our findings indicate changes in the biochemical profile of dairy cows with metabolic diseases and impaired production and fertility of dairy cows in this group. Variable importance in projection plots demonstrated that cholesterol, urea, total protein, albumin and fibrinogen in the serum were the strongest discriminators between cows with hypocalcemia and healthy cows; and AST, cholesterol, urea and triglycerides for cows with hyperketonemia and healthy cows; and cholesterol, urea, triglycerides, total protein and fibrinogen for lipomobilization and healthy cows, which might be useful as predictive biomarkers of the disease state.     

Decrease in stearic acid proportions in adipose tissues and liver lipids in fatty liver of dairy cows

Samples of liver and perirenal, mesenteric and subcutaneous fat were collected from 16 sick necropsied dairy cows to evaluate the fatty acid profiles in the hepatic and adipose tissues associated with advanced fatty liver or hepatic lipidosis. Hepatic triglyceride and eight fatty acids were measured in the hepatic and adipose tissues. Six cows had more than 3% triglyceride on fresh weight in their livers and were classified as having fatty liver. Stearic and linoleic acid proportions in the liver decreased markedly with increased hepatic triglyceride levels, while the proportion of palmitic and oleic acids increased. The most striking fluctuations in hepatic lipidosis were manifested as decreased stearic acid in the adipose tissues including subcutaneous fat with the trend of decreasing stearic acid. Palmitic acid was elevated in hepatic and perirenal fat in fatty liver cows. In instances of advanced hepatic lipidosis, palmitoleic acid increased in only subcutaneous fat and not in perirenal or mesenteric fat. In addition to the proportions of hepatic fatty acids in fatty liver, this study also clarified the fluctuations observed in the profiles of fatty acids of the adipose tissues in cows with advanced hepatic lipidosis, particularly the decline in the proportions of stearic acid.     

Whole sunflower seeds as a source of polyunsaturated fatty acids for grazing dairy cows: Effects on metabolic profiles and resumption of postpartum ovarian cyclicity

Intake of polyunsaturated fatty acids (PUFA) could modify follicular dynamics and reduce the length of the interval from calving to first ovulation (ICOV) in dairy cows, associated with changes in metabolites (i.e. cholesterol) or hormones (i.e. IGF-I). To test this hypothesis, 48 cows were stratified in two groups (primiparous or multiparous) and within each group were randomly assigned to three treatments to begin at calving: 0 kg (SS0), 0.7 kg (SS0.7) and 1.4 kg (SS1.4) of whole sunflower seeds (WSS) per cow per day. The experimental period lasted for 60 days after calving and the diets, which consisted of direct grazing of improved pastures, whole-plant wheat silage and concentrates, were designed to be isocaloric and isoproteic (1.6 Mcal NEL/kg DM, 16.7% CP). Ovaries were examined by ultrasound three times per week from day 8 postpartum (PP) until first PP ovulation. Body condition score (BCS) was determined and blood samples were collected weekly from calving to characterize the metabolic profiles. In treatments SS0.7 and SS1.4, 7/8 and 6/8 primiparous cows ovulated the first follicular wave PP, compared with only 1/8 primiparous cow in treatment SS0, while there were no treatment differences in multiparous cows. The ICOV was 44, 21 and 19 days for the primiparous, and 22, 21 and 25 days for the multiparous cows, in treatments SS0, SS0.7 and SS1.4, respectively. Treatments had no effect on BCS, plasma IGF-I and metabolic profiles except that NEFA and urea were increased by WSS supplementation. Intake of PUFA (WSS up to 1.4 kg/day or 6.7% of the diet) during early lactation reduced the ICOV in primiparous grazing dairy cows in early lactation but not in multiparous cows, and while the precise mechanism for these results is unclear, it was not related to changes in the plasma concentrations of IGF-I or cholesterol.     

The effects of short intensive exercise on plasma free amino acids in standardbred trotters

The aim of this study was to investigate the effect of short intense exercise on plasma amino acid concentrations in trotters and to test the repeatability of plasma amino acids concentration in samples obtained on two independent days under field conditions. Plasma amino acid concentrations were analysed in blood samples of 36 standardbred trotters before and after intense exercise over a distance of 2000 m. Sampling was repeated in 20 horses after 35 days. Exercise intensity was estimated from post‐exercise lactate levels. Horses were divided in two groups according to a cut‐off lactate concentration at 15 mmol/l. The plasma concentrations of alanine, aspartate, glutamate, isoleucine, leucine, lysine and taurine increased and arginine, asparagine, citrulline, glutamine, glycine, histidine, methionine, serine, tryptophan and 3‐methylhistidine decreased after exercise. Ornithine, threonine, tyrosine, phenylalanine and valine concentrations remained constant. Higher intensity of exercise significantly decreased tryptophan and increased taurine concentrations. Sampling day had a significant effect on the absolute pre‐ and post‐exercise amino acid concentrations. Exercise had a significant influence on the concentrations of most plasma amino acids in trotters. These changes could reflect shifts between the free amino acid compartments, but there were also some indications for muscle catabolism. The amino acid supply of sporting horses could be of specific significance for maintaining muscle integrity and for the improvement of post‐exercise recovery of competition horses.     

蹄叶炎奶牛血浆蛋白质组学2-DE图谱的构建及分析

采集患病牛和健康牛血浆,用人白蛋白和IgG抗体去除其高丰度蛋白后,通过双向凝脉电泳(Two dimension-al gel electrophoresis,2-DE)技术和PDQuest分析软件比较2组间血浆蛋白组表达差异.结果显示,蹄叶炎奶牛血浆2-DE图谱中有39个蛋白斑点表达上调,23个蛋白斑点表达下调,共检测到62个差异蛋白点.结果表明,奶牛发生蹄叶炎时,其血浆蛋白组表达模式发生了改变,这种改变可能与蹄叶炎的发病机制密切相关.     

Ketosis treatment and milk yield in dairy cows related to milk acetoacetate levels

Milk yield and milk acetoacetate (M-acac) were measured weekly for the first 6 weeks of lactation in 5 herds with a ketosis problem. Ketosis treatments and the corresponding ketotest score, were also recorded. The treatment rate was highest 7-16 days after calving. Most of these early cases were associated with low ketone levels in milk, whereas the treatment rate for cows with high ketone levels was highest 17-31 days after calving. Nearly half of the treated cows were low-ketone animals. They were classified as ketosis cases in the cow health card records, although probably suffering from other post partum disturbances in many instances. About 40% of the cows with high ketone levels recovered spontaneously. Reduction in milk yield associated with peak M-acac levels was transient and moderate. It was concluded that health card statistics overestimates the severity of the ketosis problem in Norway.     

Macromineral status of dairy cows with concurrent left abomasal displacement and fatty liver

Abstract

AIM: To evaluate the macromineral status of field cases of dairy cows surgically treated for left abomasal displacement (LDA), with concurrent fatty liver of different severity, and compare this for animals that died or recovered.

METHODS: Sixty-eight Holstein dairy cows with LDA and 110 control cows, from 28 farms, were used in the study. Blood samples and liver biopsies were obtained during standing surgery for correction of LDA, and from control cows. The concentration of macrominerals in serum, and of total lipids (tLPD) and triglycerides (TG) in liver were determined. Liver was examined histologically, and classified for its severity of fatty liver. Cows with LDA were grouped according to severity of fatty liver. Cows in Groups 1 to 3 recovered, whereas those in Group 4 died within 4 weeks of surgery. Group 1=mild (n=4) or moderate (n=6 cows, n=4 heifers) fatty liver, Group 2 = moderate to severe fatty liver (n=13), Group 3=severe fatty liver (n=15 cows, n=5 heifers), Group 4 = severe fatty liver (n=17 cows, n=4 heifers).

RESULTS: The concentration of macrominerals in serum was affected by the concurrence of fatty liver and LDA; Ca, K and Mg were significantly (p<0.05) lower in animals that died than those that survived. For cows with severe fatty liver, concentrations of tLD and TG were higher in the animals that died compared with those that recovered (p<0.01). Cows with LDA and severe fatty liver that died were earlier in lactation (median days in milk (DIM) 13 days) compared with the other cows with LDA (median DIM 21–26 days) (p<0.05); they were also significantly older (median 6 years old) than cows in the other groups (median 4 or 5 years old) (p–0.05).

CONCLUSIONS AND CLINICAL RELEVANCE: Concentrations of macrominerals in serum were influenced by the concurrence of LDA and fatty liver. Animals with low concentrations of Ca, K and Mg had a guarded prognosis. The concentration of K should always be evaluated in cows with LDA and concurrent fatty liver when providing a prognosis. Most cows with severe fatty liver were detected in the first 4 weeks of lactation, but older animals and those that had more recently calved had a worse prognosis.