Subclinical ketosis in dairy cows

Subclinical ketosis is defined as a preclinical stage of ketosis. The peak prevalence of subclinical ketosis occurs during the fourth week of lactation. Herd-related factors, breed, parity, and season are other important determinants. Subclinical ketosis can be revealed by determining levels of plasma glucose, plasma NEFA and blood, and milk or urine ketone body concentration. There are theoretical and practical advantages of using milk ketone bodies. Most authors are agreed on approximate lower and upper borderlines for subclinical ketosis. The risk of an outbreak of clinical symptoms has been evaluated by some authors. Most authors have found significant negative relationships between energy balance and ketone body concentration. Some disagreement may be attributable to the fact that the diets used in different experiments can have different glucogenic potential, even if the energy content is the same. This affects the relationship between energy balance and ketone body concentration, as the ketone body level is influenced by both the energy balance and plasma glucose. Feeding silage with high butyric acid content increases the risk of subclinical ketosis. There are indications that cows with the highest milk yield directly after calving are at greatest risk for developing ketosis. Increased ketone body level secondarily reduces milk production, a decrease that has been quantified by some authors. Subclinical ketosis causes delayed reproductive functions return to normal after calving, increased intervals from calving to first and last service, and an increased frequency of ovarian cysts. The routine determination of milk acetone levels in control programs can be used to evaluate the status of individual cows, to indicate the energy feeding in early lactation at a herd level, and to evaluate sires for breeding. The heritability and the tendency toward a positive genetic correlation between milk acetone and milk yield have also been discussed, as have aspects of nutritional prevention. Factors such as energy- and protein-rich roughage, tasty high-energy concentrates, suitable feeding during the dry period, and division of the concentrates into at least four meals are considered to be important.     

Epidemiology and genetic basis of ketosis in Finnish Ayrshire cattle

The epidemiology and genetic variability of ketosis in Finnish Ayrshire cattle were examined. In the spring of 1982, a new health recording system was started on all dairy farms in Finland. Ketosis data collected during the first year were analyzed. Seven percent of 8201 Finnish Ayrshire cows which were daughters of 80 randomly selected bulls were treated for ketosis. Eighty-nine percent of cases occurred within 8 weeks after parturition, with the highest occurrence 3–5 weeks after calving. When cases were categorized by month of calving the risk of ketosis was higher during indoor feeding (September-May) than during outdoor feeding (June-August). Ketosis occurrence increased with parity, but was not associated with milk yield. Problems in estimating the correlation between ketosis and milk yield were discussed. The incidence rate among bull-daughter groups varied from 0 to 26 percent. The heritability estimate of 2.3% for ketosis on the binomial scale was not significant, even though it corresponded 81% on the normal scale. Research is needed on new statistical methods for threshold characters in order that breeding programs can be designed to accoint for possible inherited susceptibility to metabolic diseases.     

An epidemiological and genetic study on registered diseases in Finnish Ayrshire cattle. III. Metabolic diseases

The epidemiology of clinical ketosis, hypocalcaemia and hypomagnesaemia was examined. In addition, the genetic variability of ketosis and parturient paresis was investigated. The data set consisted of the lactation records of 70,775 Finnish Ayrshire dairy cows. Each cow was under observation for 2 days before and for 305 days after calving. Lactation incidence rates (%) were: ketosis 6.0, parturient paresis 3.8, non-parturient paresis 0.6, hypomagnesaemic tetany, outdoor 0.6, and indoor 0.2. These diseases formed 22 % of all first treatments by veterinarians during farm visits. 92 % of the cases of ketosis occurred with 8 weeks of parturition, with the highest occurrence 3–5 weeks after calving. Four % of cases of parturient paresis occurred before, and 45 % within 24 h after calving. When cases were categorized by month of calving the risk of ketosis was higher during indoor feeding (October-April) than during outdoor feeding (May-September). The risk of parturient paresis did not significantly vary with month of calving. The occurrence of ketosis increased with parity up to the 4th and decreased thereafter. The occurrence of parturient paresis increased with parity. Both the increase in herd milk yield and the increase in individual milk yields were positively associated with the occurrence of ketosis and parturient paresis. The cows with a history of the reproductive tract infection had a higher risk of contracting ketosis. Heritability estimates for ketosis in various parity groups were from 1.6 % to 4.1 % on the binomial scale (corresponding to 7.3 %–14.4 % on the normal scale), and for parturient paresis from 3.5 to 10.5% (corresponding from 18.3 % to 27.4 %). The genetic correlation between ketosis and parturient paresis, and these and current milk production for all material were insignificant.     

用试剂法检测围产期奶牛亚临床酮病的发病规律研究

[目的]为了探讨奶牛围产期亚临床酮病的发病规律.[方法]采用试剂法检测斜沟乡上窑村94头临床健康的围产期奶牛的尿酮和乳酮.[结果]表明:试剂法可用于早期检测尿中酮体,奶牛酮病的早期诊断在产后10 d左右开始,尿酮阳性率高而敏感.[结论]尿酮阳性率集中在产后20 d内.     

Effects of long-term feeding of a diet supplemented with clinoptilolite to dairy cows on the incidence of ketosis, milk yield and liver function

Fifty-two clinically healthy Holstein cows were randomly assigned to one of three groups according to their age and parity. The first group (A) consisted of 17 cows that were fed a concentrate ration supplemented with 1.25 per cent clinoptilolite, the second group (B) consisted of 17 cows fed a ration supplemented with 2.5 per cent clinoptilolite, and the third group (C) consisted of 18 cows, which were fed the basal ration containing no clinoptilolite. The rations were fed from four weeks before the cows' expected parturition dates until the beginning of the next dry period. Blood samples were collected from each animal at the start of the experiment, on the day of calving and then monthly, and analysed for serum glucose, ketone bodies, liver enzymes, blood urea nitrogen (BUN) and total proteins. The milk yield of each cow was recorded monthly. The cows in group B had significantly fewer cases of clinical ketosis during the first month after calving and a higher total milk yield. Feeding the cows with clinoptilolite for a long period had no apparent adverse effects on their liver function, and did not significantly affect the concentrations of glucose, ketone bodies, BUN and total proteins in their serum.     

Loss of milk yield due to Akabane disease in dairy cows

Akabane disease is an infection with clinical signs of congenital malformation and abortion in ruminants. Abnormal parturitions caused by Akabane disease result in great economic loss. The purpose of this study is to estimate the reduction in the milk yield from abnormal parturition due to Akabane disease. The data were collected from 33 Holstein cows on 11 farms. The animals had abnormal parturitions during the period from September 1998 to March 1999, and were diagnosed as having Akabane disease. The mean and standard deviation of the rate of reduction in the milk yield of 33 cows after abnormal parturition caused by Akabane disease was -11.4 +/- 14.9%. The means and standard deviations of the rate of reduction of four cows calving abnormally at 220-239 days of gestation, nine cows calving abnormally at 240-270 days of gestation, and 20 cows calving abnormally at 271-300 days of gestation were -26.6 +/- 24.7%, -14.7 +/- 11.0%, and -6.9 +/- 12.3%, respectively. In this study, we demonstrated that the rate of reduction in the milk yield in cows affected by Akabane disease was -11.4 +/- 14.9%, but values as high as -26.6 +/- 24.7% were reached in the comparison with the milk yield obtained after normal parturition.     

A survey of the postpartum reproductive performance of dairy cows with fertility problems in southern Iceland

The purpose of this survey was to evaluate the reproductive performance of dairy cows on problem farms in southern Iceland. In all 229 cows on 6 farms were studied. The animals were examined clinically by rectal palpation, once a month. Blood samples were taken 2–5 and 7–10 weeks after calving. The blood samples were analysed for the contents of glucose, urea, inorganic phosphate, calcium and magnesium. Milk samples for progesterone profiles were taken, by the farmer, every 4th day from day 10 postpartum until first oestrus. Because of this sampling method, 128 cows had no rise in progesterone levels, when milk sampling was stopped. These 128 animals were excluded from the study. The results are based on 101 animals.There was a large variation between cows in postpartum reproductive performance. In the total material 1st ovulation occurred later than reported in many other countries. Fifty percent of the cows had ovulated 35 days after calving and 90 percent 70 days after calving.The first luteal phase was short in about 60 % of the cows. The progesterone values assayed from those short cycles were lower than the values assayed from the following cycle. First artificial insemination (ai) was on the average 77 days postpartum (pp). The conception rate to first service was 49 %. Of 100 milk samples taken at the time of ai, 20 had high progesterone value. This indicates a high frequency of luteal phase inseminations.Clinical ketosis was diagnosed in 35 cows. Of these, 31 had a low glucose value. Cows with clinical ketosis ovulated, on the average, later than other animals and 24 ovulated later than 40 days pp. The results indicated that the fertility problems of these cows studied were late ovulations, low conception rate, probably in part, due to luteal phase inseminations, and a high frequency of ketosis which could be caused by low quality feedstuff.     

Management practices associated with udder health of first-parity dairy cows in early lactation

This study aimed at investigating associations between management routines including feeding, housing, and milking around calving, and udder health of first-parity cows in early lactation in Swedish large, high producing, low bulk-milk somatic cell count (SCC) dairy herds housed in free stalls. Seventy-two dairy herds participated and data concerning 1189 first-parity cows calving during the study period (October 2005-January 2006) was collected. Multivariable regression analysis were performed with three different outcomes; within-herd number of first-parity cows veterinary treated for clinical mastitis at days -10 to 60 after calving, within-herd number of first-parity cows with a SCC> or =200,000cells/mL at first test-day, and SCC of first-parity cows at first test-day. Cow factors significantly associated with good udder health of first-parity cows (few cases of clinical mastitis and or low SCC) were being of the Swedish Red breed, having a high milk yield at first test-day, and a milk-urea > or =5mmol/L at first test-day. Herd factors significantly associated with good udder health were having mattresses as flooring in the cubicles in the lactating cow housing, and to house the first-parity cows in tie stalls 1 month before calving. Cow factors significantly associated with poor udder health of first-parity cows were having a milk-urea <4mmol/L at first test-day. Herd factors significantly associated with poor udder health of first-parity cows were feeding first-parity cows sugar-beet pulp or corn silage, and to give silage from a different batch to pregnant heifers than to lactating cows. Moreover, to have sawdust or shavings in the calving pen, to be moved from the calving pen > or =2 days after calving, to milk first-parity cows at the calving site instead of in the parlor, and to rinse, clean or disinfect milking units before a first-parity cow was milked were also significantly associated with poor udder health of first-parity cows. The results indicate that different control measures must be taken depending on the nature of the udder health problem.     

Subclinical ketosis: prevalence and associations with production and disease.

Cows in 32 southern Ontario Holstein herds were monitored for subclinical ketosis for a period of two and one half years. Milk samples were routinely collected and the level of milk ketone bodies determined by the use of a commercial nitroprusside based test powder (reactions scored as negative, +1 or +2). Approximately 92% of positive reactions were observed in the first 65 days of lactation and for that time period the prevalence of ketosis was 12.1%. Based on this prevalence, the minimum possible duration of subclinical ketosis would be 7.9 days and the minimum possible lactational incidence rate would be 12.1%. The prevalence during the first 65 days of lactation in individual herds ranged from 0 to 33.9%. Subclinical ketosis was more likely to be found in cows experiencing metritis than in unaffected cows. Detection of elevated levels of milk ketones also indicated that the cow had a significantly higher risk of having clinical ketosis, metritis or cystic ovaries diagnosed within the following four days. Milk ketone scores of +1 and +2 were found to be associated with a reduction in daily milk production of 1.0 and 1.4 kg of milk respectively.     

Relationships between the plasma concentrations of insulin-like growth factor-I in dairy cows and their fertility and milk yield

The relationships between insulin-like growth factor-I (IGF-I) and the fertility and milk yield of Holstein-Friesian dairy cows were investigated. The concentration of IGF-I in blood was measured weekly from one week before to 12 weeks after calving in 177 multiparous cows and at four times during this period in 142 primiparous cows; the concentration of IGF-I in milk was measured in 50 of the multiparous cows. The plasma concentrations of IGF-I were higher in the primiparous than in the multiparous animals. In the primiparous cows, high concentrations of IGF-I before calving were associated with longer calving to conception intervals. Conversely, in the multiparous cows low concentrations of IGF-I before and after calving were associated with a failure to conceive, despite repeated services. Multiparous cows with IGF-I concentrations of greater than 25 ng/ml in the week after calving were 11 times more likely to conceive to first service than those with lower concentrations. Concentrations of IGF-I greater than 50 ng/ml at first service increased the likelihood of conception five-fold. Cows with higher peak milk yields had lower plasma concentrations of IGF-I and took longer to return to ovarian cyclicity. The negative relationship between milk yield and return to cyclicity was stronger in the multiparous cows (P < 0.002) than in the primiparous cows (P < 0.04). The concentrations of IGF-I in milk followed a different pattern and were not associated with the changes in plasma IGF-I or fertility.     

Suppression of interferon response of bovine leukocytes during clinical and subclinical ketosis in lactating cows.

The influence of spontaneous ketosis on interferon alpha and gamma production in blood leucocytes and on PHA induced lymphocyte blastogenic response was investigated. Twenty three cows 4.13 +/- 2.8 weeks after calving were divided into three experimental groups on the basis of blood ketone bodies, glucose and free fatty acids concentrations. The leukocytes of cows with clinical symptoms and the highest concentration of ketones and free fatty acids in blood responded with the lowest levels of interferons alpha and gamma to three interferon inducers: Newcastle Disease Virus (NDV), phytohemagglutinin (PHA) and concanavalin A (ConA). Depression in interferon PHA stimulated synthesis correlated with a very low mitogenic response of blood lymphocytes. Blood leukocytes of cows with subclinical ketosis, characterized by mild clinical symptoms and a lower concentration of ketones in blood in comparison to cows with clinical ketosis, responded better to interferon and mitogenic stimulation; however, the interferon titer and blastogenesis were still lower than in leukocytes of healthy cows. Correlation between the stage of ketosis and the level of interferon production in milk leukocytes was also observed. A possible relationship between the suppression of interferon production in blood leukocytes and the increased concentration of ketone bodies in blood is discussed.     

Effect of parity number on the dry matter intake of dairy cows during the first week after calving

We investigated the effect of parity number on the dry matter intake (DMI) of cows during the first week after calving. Eighty‐three cows were evaluated from 14 days before to 7 days after calving. DMI and milk yield were measured for 7 days after calving, and the calving score was measured. Blood samples were collected throughout the experiment. The average DMI during the first week after calving was reduced in the first‐lactation heifers and high‐parity number cows. A quadratic relationship between the parity number and the DMI was observed. The first‐lactation heifers had lower prepartum serum total protein (TP) concentration and milk yield, higher prepartum serum nonesterified fatty acid (NEFA) concentration and calving score than the multiparous cows. The recovery rate of serum calcium (Ca) after calving was slow in the cows in the parity 6. The DMI was positively affected by the serum Ca concentration after calving, milk yield, and prepartum serum TP concentration and was negatively affected by the calving score and prepartum serum NEFA concentration. We conclude that the DMI immediately after calving tends to be lower in first‐lactation heifers and high‐parity number cows, but factors that reduce the DMI differ according to parity number.     

Effect of administration of a controlled-release monensin capsule on incidence of calving-related disorders, fertility, and milk yield in dairy cows

OBJECTIVE: To determine the effect of a controlled-release monensin capsule administered at cessation of lactation on incidence of calving-related disorders, fertility, and milk yield in dairy cows. ANIMALS: 290 dairy cows treated with monensin and 290 untreated control cows. PROCEDURE: Treated cows received a capsule that released monensin at 335 mg/d for 95 days. Incidence of calving-related disorders; daily milk yield up to 20 days postpartum; test-day milk yield, fat, protein, and mature-equivalent 305-day milk production; and body condition score at calving were determined. Reproductive variables were conception rate at first service, pregnancy rate, and calving-to-conception interval. RESULTS: Cows treated with monensin were 2.1 times as likely to develop dystocia and 0.8 times as likely to develop metritis as control cows. For milk yield, there was an interaction of treatment X time X parity. In multiparous cows, monensin significantly improved milk yield at test days 4 and 7. In addition, monensin increased body condition score at calving. CONCLUSIONS AND CLINICAL RELEVANCE: Despite increasing the likelihood of developing dystocia and metritis, administration of monensin improved the lactational performance of multiparous cows and may be a promising additive for use at the time of cessation of lactation.     

奶牛酮病发病原因及其对生产性能影响调查分析

探索奶牛酮病发病原因、发病规律及其对生产性能的影响,对986头围产期奶牛进行跟踪调查分析。结果表明,奶牛酮病发病率为31.74%,死亡率为4.15%;秋季发病率最高,可达37.4%,其次是冬季和夏季,春季发病率最低;随着胎次、年龄和产乳量的增加,奶牛酮病的发病率明显增高;在第1个泌乳月奶牛酮病的发病率最高,可达50.43%;日粮种类和微量元素越少,奶牛酮病就越容易发生;奶牛发病后受胎率明显降低;发病后产乳量、乳脂率、乳蛋白率、乳糖率和乳干物质比发病前均明显降低,差异显著（P〈0.05）。奶牛酮病发病具有一定的规律性,且可降低奶牛的繁殖性能、产奶量和乳品质。     

An epidemiological and genetic study on registered diseases in Finnish Ayrshire cattle. IV. Clinical mastitis

The epidemiology and genetic variability of clinical mastitis were examined. The data consisted of 70,775 Finnish Ayrshire cows. All cows were from milk recorded herds and calved during 1983. Each cow was under observation from the date of calving for 305 days. Only clinical mastitis diagnosed and treated by a veterinarian during the farm visits were taken into account. The lactation incidence rate of clinical mastitis (LIR) was 5.4 %. The cows calving in April-May had the highest LIR, but the seasonal variation was relatively small. The LIR increased with parity from the first to sixth parity. The cows treated for parturient paresis, infertility or ketosis had a higher risk of clinical mastitis than cows not treated for these diseases. The LIR was higher in herds with a high milk production level. The highest odds ratio estimated from parameters of the logit model was 14.8. The heritability estimates for clinical mastitis on the binomial scale were 3.2 % in parity 1, 1.6 % in parity 2, 0.6 % in parity 3 and 4, and 0.8 % in all parities (corresponding to 19.7 %, 8.3 %, 2.6 % and 3.8 % on the normal scale). These estimates indicate sufficient assurance for progeny testing of bulls and some possibilities of genetic selection against clinical mastitis. Genetic correlations between clinical mastitis and 305-days milk yield were 0.39 in parity 1, 0.51 in parity 2, 0.18 in parity 3–4 and 0.58 in all parities. This means that the best sires for milk yield had daughters with a higher LIR for clinical mastitis than the other sires.     

两种定性检测方法对围产期奶牛亚临床酮病的检测结果比较

采用酮粉法和试剂法检测贵南县两个奶牛场135头临床健康的围产期奶牛的尿酮和乳酮,结果表明,试剂法和酮粉法均可用于早期检测尿中酮体,临床上以粉剂法更佳;奶牛酮病的早期诊断应在产后10d左右开始,尿酮阳性率高而敏感,而乳酮阳性率低;尿酮阳性率集中在产后20d。     

Papillomatous digital dermatitis on a commercial dairy farm in Mexicali, Mexico: Incidence and effect on reproduction and milk production

This retrospective study of papillomatous digital dermatitis (PDD) was performed using data for cows that calved between July 1993 and June 1994 on a Mexicali, Mexico, dairy farm in order to calculate incidence rates, and to compare milk yield and reproduction data between affected and nonaffected dairy cows. A total of 190 out of 577 (33%) cows were affected during lactation and six (1%) during the dry period. Fifty-two of 77 (68%) cows that had lesions in the previous lactation and were also present on the farm in the current lactation had lesions in the current lactation. The highest risk for PDD occurred during the first month of lactation (9%). The yearly estimated cumulative incidence risk was 35% and the incidence density rate was 44.6 cases per 1000 cow-months. More animals were affected in summer and fall than in winter and spring. Purchased animals were 3.4 times more likely to be affected than animals born on the farm. Survival analyses indicated healthy cows conceived 93 days after calving (median), but affected cows conceived 113 days after calving (median) (P < 0.01). PDD-affected animals produced less milk than healthy cows, but the difference was not statistically significant in the multiple regression.     

The effects of calcium supplementation of dairy cattle after calving on milk, milk fat and protein production, and fertility

AIM: To determine the effect of calcium supplementation of dairy cattle after calving on serum concentrations of calcium, magnesium, and phosphorous after calving, and on reproductive and productive performance in the following lactation. METHODS: This was a double-blind randomised clinical trial using 356 dairy cows of parity 3 or greater from six seasonally calving commercial dairy herds. Cows were randomly assigned to a treatment and control group. The treatment group received two doses of 380 ml of calcium chloride in oil (49 g of elemental calcium); the first dose was given as soon as practical after calving and the second 12 hours later. Control cows received 380 ml of a placebo using the same treatment regime. Treatment and control cows had blood samples taken during the first 7 days after calving to determine serum calcium, magnesium and phosphorous levels. Treatment and control cows were monitored throughout the lactation to measure production and reproductive performance. RESULTS: Treatment had no effect on PSM to first service intervals. Treatment significantly reduced PSM to conception intervals in only one of the four herds with data available for analysis (p = 0.09). There was no difference between treatment groups for adjusted corrected milk yield calculated from the first herd test milk yield (p = 0.93) or 305-day milk solids production (p = 0.19). CONCLUSION: Further studies are required to identify reasons for the between-herd effectiveness of calcium chloride treatment in improving fertility.     

产犊季节、胎次及牛场对荷斯坦牛泌乳性能的影响

[目的]研究产犊季节、胎次及不同牛场对奶牛泌乳性能的影响情况,以期为提高奶牛的泌乳性能及牛奶质量提供可靠的理论依据。[方法]收集3个千头以上奶牛场共8 872次相关信息,用多因素方差分析法分析产犊季节、胎次和牛场对泌乳天数、305d校正奶量、305d脂肪产量、305d蛋白产量和全泌乳期产奶量5个泌乳性能的影响进行分析。[结果]不同产犊季节、胎次和牛场都极显著影响奶牛的5项泌乳性能(P<0.01)。夏季和秋季产犊奶牛的泌乳性能较为理想。夏季产犊奶牛的泌乳天数和全泌乳期产奶量最高,其他三个泌乳性能都位居第二;秋季产犊奶牛的305d校正奶量、脂肪产量和蛋白产量都显著高于其他三个季节(P<0.05),泌乳天数和全泌乳期产奶量也仅次于夏季。头胎牛的各项泌乳性能都显著高于其他胎次的奶牛(P<0.05),其次为2胎产犊奶牛。随着胎次的增加,泌乳性能的各项指标都有不同程度的降低。除了泌乳天数之外,A牛场的各项泌乳性能都最佳,且显著高于B、C两个奶牛场(P<0.05)。[结论]在饲养条件良好的情况下,本研究中三个牛场的奶牛适宜在夏、秋两个季节产犊,此时泌乳性能较好;此外,头胎产犊奶牛的泌乳性能在各胎次中最高。     

Effects of clinical mastitis on reproductive and milk performance of Holstein cows in Morocco

The aim of this study was to determine the influence of clinical mastitis and time of first mastitis occurrence on reproductive and milk performance of Holstein cows. Data were collected in a dairy farm from 2008 to 2012 on 1725 cows, among which 464 cows with mastitis. To determine the influence of clinical mastitis on reproductive and milk performance, models included fixed effects of parity, calving season, calving year, and group (cows with and with no mastitis). To determine the effect of time of 1st mastitis occurrence on reproductive performance, the mastitic cows group was further reclassified into three groups: prior to 60 days, between 60 and 90 days and greater than 90 days postpartum. For milk performance, the mastitic cows group was divided into two groups: before and after peak milk yield. Clinical mastitis had significant effects on calving to first AI interval, milk yield, and fat yield, but a non-significant effect on days open, number of inseminations per conception, and milk fat percentage. Mastitic cows had a calving to first AI interval 6.1 days longer and 549.6 kg milk and 20.4 kg fat per 305 days of lactation lower than those with no mastitis. Time of 1st mastitis occurrence did not have any significant effect on reproductive performance. Further, milk and fat yields of cows diseased before peak milk yield were 506 kg and 23.9 kg, respectively, lower than those of cows affected after peak milk yield. Extra attention needs to be paid to mastitis during the early postpartum period.