Ketosis Research Articles

Hemichorea associated with non⁃ketotic hyperglycemia: a case report

Hemichorea associated with non⁃ketotic hyperglycemia: a case report

Genetic parameters for producer-recorded health data in Canadian Holstein cattle

Health traits are of paramount importance for economic dairy production. Improvement in liability to diseases has been made with better management practices, but genetic aspects of health traits have received less attention. Dairy producers in Canada have been recording eight health traits (mastitis (MAST), lameness (LAME), cystic ovarian disease (COD), left displaced abomasum (LDA), ketosis (KET), metritis (MET), milk fever (MF) and retained placenta (RP)) since April 2007. Genetic analyses of these traits were carried out in this study for the Holstein breed. Edits on herd distributions of recorded diseases were applied to the data to ensure a sufficient quality of recording. Traits were analysed either individually (MAST, LAME, COD) or were grouped according to biological similarities (LDA and KET, and MET, MF and RP) and analysed with multiple-trait models. Data included 46 104 cases of any of the above diseases. Incidence ranged from 2.3% for MF to 9.7% for MAST. MET and KET also had an incidence below 4.0%. Variance components were estimated using four different sire threshold models. The differences between models resulted from the inclusion of days at risk (DAR) and a cow effect, in addition to herd, parity and sire effects. Models were compared using mean squared error statistic. Mean squared error favoured, in general, the sire and cow within sire model with regression on DAR included. Heritabilities on the liability scale were between 0.02 (MET) and 0.21 (LDA). There was a moderate, positive genetic correlation between LDA and KET (0.58), and between MET and RP (0.79).

Serum calcium and magnesium level in dairy cows at calving

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

Short communication: Interaction of energy balance, feed efficiency, early lactation health events, and fertility in first-lactation Holstein, Jersey, and reciprocal F1 crossbred cows

First-lactation Holstein (HH), Jersey (JJ), and crossbred cows (HJ and JH, with sire breed listed first, followed by dam breed) were observed for cumulative energy intake (CEI15) and energy used for milk production (CEL15) at wk 15 of lactation in addition to recordings of health problems and pregnancy. Cumulative energy balance (CEB15) was calculated from CEI15 and estimates of expenditures at wk 15 of lactation. Feed efficiency (FE15) was calculated by dividing CEL15 by CEI15. Data included 140 cows with 43, 34, 41, and 22 in the HH, HJ, JH, and JJ groups, respectively. The first incidence of displaced abomasum (DA), ketosis (KET), mastitis (MAST), and metritis (MET) was recorded in the first 100 d of lactation with an incidence of the disease coded as 1 and no incidence coded as 0. Pregnancy (PREG) at d 150 was recorded as 1 if a cow had conceived by d 150 and 0 if she had not. Logistic regression was used to analyze health and fertility with fixed effects in the model including genetic group, linear and quadratic effects for age at calving, and year-season of freshening group. Pregnancy was analyzed with the same variables and the addition of CEB15. In other analyses, CEB15, CEI15, CEL15, and FE15 were response variables with the same explanatory variables plus health events (MAST, DA, MET, and KET), where each health event was a separate analysis. Genetic group effects were significant in the occurrence of MAST and a trend for MET, but were not significant for PREG, DA, and KET. Significant odds ratio for MAST was 19.6 for HJ cows when compared with that for HH cows. Thus, HJ cows were 19.6 times more likely than HH cows to have an incidence of MAST. The trend was for HJ and JH to have a lower odds ratio of MET than that of HH. No other genetic group effects were significant in any of the disease and PREG models. The linear and quadratic terms for age at calving were not significant. An occurrence of MAST decreased FE15 by 5.2±2.2%. Mastitis also decreased CEI15 and CEL15, but the compensatory reductions left the CEB15 unaffected. An occurrence of a DA decreased CEI15 and an incidence of KET decreased CEB15.

Syncope and metabolic disorders in children

Syncope is a common pediatric emergency event,which can be caused by various metabolic disorders different from other illness. The major metabolic anomalies include hypoglycemia, hyperventilation,electrolytes imbalance,hypoxemia and others, in which hypoglycemia is caused by hyperinsulinemia,pituitary and adrenal disease, diabetes, ketotic hypoglycemia, inherited metabolic disorders of sugar, organic acids and amino-acids,etc. This article introduced the common metabolic anomalies and their causes,diagnosis and therapy. Key words: Syncope; Hypoglycemia; Hyperventilation; Electrolyte imbalance; Hypoxemia; Inherited metabolic disorders

South Asian version of flatbush diabetes mellitus- A case report and review article

Ketosis prone type 2 diabetes mellitus which was once described as “atypical diabetes” is being recognized increasingly worldwide; being originally described in African population has been seen in multiple ethnic groups, especially in urban areas. These patients are typically obese, middle-aged men with a strong family history of type 2 diabetes. The pathophysiologic mechanisms involved in its cause are unknown, but preliminary evidence suggests that patients with ketosis-prone type 2 diabetes have a unique propensity to glucose desensitization. These individuals have negative autoantibodies associated with type 1 diabetes but frequently HLA class II DRB1*03 and/or DRB1*04 are detected. Severe impairment of both insulin secretion and insulin action are found at presentation. Aggressive diabetes management results in marked improvement in beta cell function and insulin sensitivity sufficient to allow discontinuation of insulin therapy within a few months of treatment. In the long run, insulin can be substituted with oral hypoglycemic agents in most of these patients under careful supervision and close follow up. Molecular investigations into KPD syndromes utilizing multiple approaches (genomic, metabolic, proteomic) to generate etiological hypotheses can help us understand the underlying defects of insulin secretion and sensitivity in these and other types of diabetic patients. Key words: Diabetesis mellitus (DM), ketosis prone diabetes (KPD), diabetic ketoacidosis (DKA), latent auto-immune diabetes of adults (LADA).

Phenotypic and genetic relationships of common health disorders with milk and fat yield persistencies from producer-recorded health data and test-day yields

The objective of this study was to investigate phenotypic and genetic relationships of common health disorders in dairy cows with milk (PMY) and fat (PFY) yield persistencies. Health and production data from 398 commercial dairy herds were used. Disease traits were defined in binary form for individual lactations considering mastitis only during the first 100 d in milk (MAST1), only after 100 d in milk (MAST2), and at any stage of lactation (MAST), and reproductive disorders (REPRO), metabolic disorders (METAB), and lameness (LAME). The persistencies were defined to be uncorrelated with 305-d yields. Impact of the diseases on PMY and PFY were investigated separately in first (FL) and later (LL) lactations. Phenotypic associations of PMY and PFY with likelihood of diseases in current and subsequent lactations were examined using odds ratios from a logistic regression model. Linear-threshold sire-maternal grandsire models were used to estimate genetic correlations of displaced abomasums (DA), ketosis (KET), metritis (MET), MAST, MAST1, and MAST2 with PMY and PFY across parities. Metabolic diseases and REPRO had significantly positive relationships with PMY and PFY in both FL and LL. Significantly greater PMY and PFY were associated with MAST1 in LL. Significantly lower PMY and PFY were related to MAST2 in both FL and LL, whereas cows affected by MAST had significantly less persistent lactations. Incidence of MAST and MAST2 decreased with increasing PMY and PFY in the present and previous lactation. Heritability of disease incidences were 0.03 (DA), 0.01 (KET), 0.10 (MAST), 0.02 to 0.05 (MAST1), 0.02 (MAST2), and 0.04 to 0.10 (MET). Displaced abomasum, KET, MAST, MAST1, and MET had unfavorable genetic correlations of 0.35, 0.46, 0.17, 0.02, and 0.27 with PMY, and 0.16, 0.21, 0.07, 0.06, and 0.12 with PFY, respectively. Favorable genetic correlations were found for MAST2 with PMY (−0.24) and PFY (−0.04). Results suggest that diseases in early lactation increase persistency of milk and fat yield. Selection for greater lactation persistency must consider these antagonistic relationships.

Inferring relationships between health and fertility in Norwegian Red cows using recursive models

Health and fertility are complex traits, and the phenotype for one trait may affect the phenotype of one or more other traits. For instance, disease in early lactation may impair a cow's ability to show estrus and to conceive after insemination. The objectives of the present study were to explore phenotypic and genetic relationships among health and fertility traits in Norwegian Red cows using a recursive effects model, which allows disentangling causal effects of phenotypes from the genetic and environmental correlations among traits. Records of interval from calving to first insemination (CFI), nonreturn rate within 56 d after first insemination (NR56), clinical mastitis (CM), ketosis (KET), and retained placenta from 55,568 first-lactation daughters of 1,577 Norwegian Red sires were analyzed. Trivariate recursive Gaussian-threshold models were used to analyze the 2 fertility traits (CFI and NR56) together with 1 disease trait in each analysis. The estimated structural coefficients of the recursive models imply that presence of KET or retained placenta lengthened CFI, whereas causal effects from CM to fertility were negligible. Recursive effects of disease on NR56, and of CFI on NR56, were all close to zero. Genetic correlations between health and fertility traits were low or moderate. The strongest genetic correlation was between KET and CFI (0.29), whereas genetic correlations between CM and NR56 and between CFI and NR56 were nil. In general, selection against disease is expected to slightly improve fertility (shorter CFI and higher NR56) as a correlated response and vice versa. The present results suggest that the use of structural-equation models, such as the one used here, may enhance our understanding of complex relationships among traits.

Analysis in related factors of deep vein thrombosis formation in diabetic patients and the nursing strategy

Objective To study the related factors in diabetic patients with lOwer extremital deep vein thrombosis(DVT) and the nursing strategy. Methods 58 diabetic cases underwent lower limbs 99mTc-MAA veins imaging and/or ultrasunography. The related laboratory data such as fasting plasma glucose(FPG),blood cholesterol, blood triglycerides and clinic informations such as age, disease courses, lower limbs symptoms (swelling, erooted veins and diabetic foot) and acute complication (diabetic ketoacidosis and hyperosmolar non ketotic diabetic coma) were collected simultaneously. The relationship of each factors with DVT incidence were analyzed. Results 28 patients (48.3%) complicated with lower limbs DVT. The DVT incidence was signifi-cantly different among patients with different age, disease courses, FPG, blood cholesterol, blood triglycerides, lower limbs symptoms and acute complication, respectively. No significant difference was seen in patients with different blood pressure, body weight index, diabetes type. Conclusions Various dangerous factors accumu-lating in DM such as old age, long disease courses, high FPG, high blood cholesterol and high blood triglyc-erides contribute to the high incidence of lower limbs DVT. Early intervention, comprehensive treatment and in-tensive nursing should be applied to reduce the incidence of DVT. Key words: Diabetes mellitns; Deep vein thrombosis; Related factors; Nursing strategy

Effect of DKA on QTc Prolongation in Children Might Be Mediated by Ketosis, Not Electrolyte Abnormalities

Ketotic conditions have been shown to be associated with prolonged QTc interval and sudden cardiac death. In an observational study, researchers

Effectiveness of the Ketogenic Diet

The ketogenic diet is high in fat, low in carbohydrate, and adequate in protein, and it induces ketosis. Observational studies have documented that the ketogenic diet reduces seizure frequency in children with epilepsy. However, no prior randomized trial has been done to assess the diet’s efficacy. For this randomized, controlled trial, researchers …

Supplementing Holstein Cows with Low Doses of Bovine Somatotropin Prepartum and Postpartum Reduces Calving-Related Diseases

The objective of this study was to evaluate whether supplementing Holstein cows with bovine somatotropin (bST; 142.8 mg/14 d), beginning at 21 d (±3 d) before expected calving and continuing through 42 d in milk (±3 d), affected the incidence rates of retained fetal membranes (RFM), metritis (MET), clinical mastitis (MAS), digestive problems (DIG), ketosis (KET), milk fever (MF), displaced abomasum (DA, left or right), lameness (LAM), or number of sick cows during the first 60 d in milk. Data for multiparous Holstein cows from 3 separate trials were merged for analyses (n=437). Cows in the bST-supplemented group (n=162) received biweekly subcutaneous injections of Posilac, whereas control cows (n=166) and a group of cohorts (n=109) were not supplemented. Incidences of disease were collected from the herd health records. Across all treatment groups, the incidence rates (number of diseased cows divided by the total number of cows) for RFM, MET, MAS, DIG, KET, MF, DA, and LAM were 8.47, 18.31, 16.02, 4.35, 4.35, 3.66, 3.20, and 3.66%, respectively. The incidence rates of RFM, MET, MAS, DIG, KET, MF, DA, and LAM for cows in the bST-supplemented, control, and cohort groups were 6.79, 7.83, and 11.93%; 16.05, 7.47, and 22.94%; 10.49, 18.07, and 21.10%; 1.23, 5.42, and 7.34%; 1.23, 6.02, and 6.42%; 2.47, 4.22, and 4.59%; 2.47, 3.61, and 3.67%; and 3.70, 3.61, and 3.67%, respectively. The percentages of sick cows (number of cows having one or more cases of disease divided by the total number of cows) in the bST-supplemented, control, and cohort groups were 33.95, 43.37, and 49.54%, respectively. Significant chi-squared values were detected between the bST-supplemented and control groups for MAS, DIG, and KET, with a greater number of healthy cows in the bST-supplemented group. No differences in incidences of diseases or sick cows were detected between the control and cohort groups. Results indicated that a low dose of bST supplemented to Holstein cows for 3 wk prepartum through 60 d in milk reduced the incidences of some calving-related diseases compared with nonsupplemented controls or cohorts. Importantly, no negative effects of bST supplementation on postpartum calving diseases were detected compared with nonsupplemented cows.

Selection Responses for Disease Resistance in Two Selection Experiments with Norwegian Red Cows

Genetic trends for clinical mastitis (CM), ketosis (KET), retained placenta (RP), and 305-d protein yield (PY305) were calculated for 2 Norwegian dairy cattle selection experiments. The first experiment, accomplished from 1978 to 1989, included groups selected for high (HMP) and low milk production (LMP). The second experiment started in 1989 and included selection for high protein yield (HPY) and low mastitis frequency (LCM). In both experiments proven sires from the active breeding program of Norwegian Red were used as sires. To take into account that selection of sires was external to the experiment, all available data from the Norwegian Red population, including disease records for 2.7million first-lactation cows, were analyzed with a multivariate animal model. Estimated breeding values for cows in the experiments were extracted from this analysis to calculate genetic trends in the selection groups. Genetic trends for PY305 were, as expected, positive for the HMP and HPY groups, and negative for LMP and LCM. The HMP group showed increasing genetic trends for all 3 diseases, arguably a correlated response after selection for increased milk production, whereas the LCM group showed decreasing genetic trends for CM, KET, and RP. The genetic trends for KET and RP in the LCM group are most likely correlated responses after selection against CM. After 5 cow-generations the genetic difference between HPY and LCM was 10 percentage units CM, 1.5 percentage units KET, and 0.5 percentage units RP.

Hyperglucagonemia - a Potent Threat which can Worsen the Diabetes Mellitus

Background: Diabetic ketoacidosis and hyperosmolar hyperglycemic non-ketotic coma (HHNK) are two serious acute complications of diabetes mellitus. DKA consists of the biochemical triad of hyperglycemia, ketonemia and acidemia. In DKA and HHNK dehydration and sodium depletion is seen. Lack of insulin causes hyperglycemia and also inhibits entry of potassium into the cells leading to hyperkalemia. Moreover Hyperglucagonemia also contributes to hyperglycemia and can worsen the diabetic state. Study Design: This study was retrospective, analytical case control study. Non - probability convenient sampling technique was used. Materials and Methods: We reviewed the hospital admissions and patients coming to OPD with type1 & 2 diabetes mellitus as well as diabetic complications like diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic non-ketotic coma (HHNK). We compared the groups for plasma glucose, plasma osmolality, plasma glucagon, serum electrolytes and arterial blood gases (ABGs) with control group. Results: Twelve persons were considered as control being non-diabetic with normal oral glucose tolerance. Mean plasma glucose level & mean plasma osmolality level in the patients of uncontrolled type 2 diabetes mellitus, uncontrolled type I diabetes mellitus, DKA and HHNK was significantly higher (p < 0.001) as compared with control subjects. Mean plasma glucagon level in the patients of uncontrolled type I diabetes mellitus and DKA was found significantly higher (p < 0.001) as compared with control subjects. Serum potassium level was significantly higher in patients of uncontrolled type 2 diabetes mellitus, uncontrolled type 1 diabetes mellitus, HHNK (p <0.001) and DKA (p <0.01) as compared with control subjects. Arterial pH was significantly lower in patients of DKA (p < 0.001), uncontrolled type 1 diabetes mellitus (p < 0.05) and HHNK (p < 0.01). Arterial PCO 2 was significantly lower in patients of DKA (p < 0.05). Plasma bicarbonate levels were found significantly lower in patients of DKA (p < 0.001) and HHNK (p < 0.01). Discussion: The present study showed that in type 1 DM hyperglucagonemia was more marked leading to excessive ketone bodies production and resulting in DKA. The ketoacids formed during DKA are strong acids that fully dissociate at physiological pH. So ketonuria lead to excretion of positively charged cations (Na + , K + , NH 4 + ). Moreover, the hydrogen ions were titrated by plasma bicarbonate ions, resulting in metabolic acidosis and retention of anions lead to increase in the plasma anion gap in DKA. The degree of hyperosmolality and hyperglycemia was more marked in patients with HHNK as compared with DKA. The osmotic effects of glycosuria resulted in impairment reabsorption of NaC1 and H 2 O and ultimately hyponatremia. Whereas Serum potassium level was found to be significantly higher in uncontrolled type I diabetes mellitus, uncontrolled type 2 diabetes mellitus, DKA and HHNK. These observations were according to the results of previous studies. Conclusions: Hyperglucagonemia causes marked hyperglycemia under conditions of relative insulin deficiency and can worsen the diabetic state like development of DKA when insulin deficiency becomes absolute as in type 1 diabetes mellitus. Key words: Diabetes mellitus (DM), diabetic ketoacidosis (DKA), hyperosmolar hyperglycemic non-ketotic coma (HHNK), arterial blood gases (ABGs), plasma osmolality.

Avaliação do perfil metabólico, nutricional e efeitos adversos de crianças com epilepsia refratária em uso da dieta cetogênica

OBJETIVO: Avaliar os efeitos adversos, o perfil metabólico e o crescimento pôndero-estatural de crianças com crises epilépticas de difícil controle, as quais foram submetidas a dieta cetogênica. MÉTODOS: Selecionaram-se 23 pacientes na faixa etária de 2 até 17 anos com epilepsia de difícil controle medicamentoso, sendo 43,5% (n=10) do sexo masculino e 56,5% (n=13) do sexo feminino, provenientes do Setor de Neuropediatria da Disciplina de Neurologia da Universidade Federal de São Paulo. Foram submetidos a dieta cetogênica e acompanhados por um período mínimo de um ano. Dois pacientes não conseguiram manter a cetose por falta de adesão dos pais à dieta. RESULTADOS: Os efeitos adversos encontrados foram reversíveis, incluindo hiperlipidemia, obstipação (17,4%), náuseas e vômitos (43,4%), sonolência (47,8%), infecções intercorrentes (3,0%), recusa da dieta (13,0%) e epistaxe (4,3%). O crescimento pôndero-estatural não foi afetado, tendo o peso e a estatura seguido o percentil adequado. CONCLUSÃO: A dieta cetogênica pode constituir-se em uma alternativa segura e efetiva para o tratamento de crianças com epilepsia refratária.

Study on the occurrence and inducement of ketosis and ketoacidosis in patient with diabetes mellitus

目的 探讨糖尿病酮症(diabetic ketosis,DK)和糖尿病酮症酸中毒(diabetic ketoacidosis,DKA)患者的发病情况及诱发因素.方法302例DK和DKA患者为研究对象,采用描述性研究方法,调查与分析DK和DKA患者的发病情况及诱发因素.结果302例患者共发生DK和DKA382例次,78.01%的DK和DKA患者有明确诱发因素,感染(55.37%)、胰岛素剂量不足或中断(12.75%)、口服控制血糖药物中断或剂量不足(11.07%)、应激状态(10.40%)为常见的诱发因素,其他因素有饮食失调(6.71%)、过度疲劳(4.36%)、妊娠和分娩(0.67%).初发糖尿病110例(28.79%),发生1次258例,发生2次29例,发生3次以上14例,发生17次1例.结论应高度重视对DK和DKA患者的诱发因素评估,复习发生前情况,关注导致DK和DKA的诱发因素(感染、中断胰岛素、不合理治疗等).加强对DK和DKA患者的教育,预防感染,提高患者治疗依从性,坚持注射胰岛素和口服控制血糖药物,对预防、减少DK和DKA的发生有重要意义。

Insulin and glucagon ratio in the patho-physiology of diabetic ketoacidosis and hyperosmolar hyperglycemic non-ketotic diabetes.

To assess the role of insulin / glucagon ratio in pathophysiology of diabetic ketoacidosis and hyperosmolar hyperglycemic non-ketotic diabetes. Case control, analytical study. Military Hospital, Rawalpindi from September 2003 to August 2004. The study included 7 patients with diabetic ketoacidosis, 3 patients with hyperosmolar hyperglycemic non-ketotic diabetes, 8 patients with uncontrolled type 1 diabetes mellitus and 12 patients with uncontrolled type 2 diabetes mellitus. Twenty non-diabetic persons having blood glucose level less than 6 mmol/L were selected as control group. Patient s detailed history was taken and general physical examination was done. Plasma samples of all the patients and control subjects were assayed for plasma glucose, glycosylated hemoglobin, plasma insulin and glucagon levels. Presence or absence of ketone bodies in urine was also determined. Seven patients with diabetic ketoacidosis, 3 females and 4 males, were found to be hyperglycemic ( p<0.001 ), hypoinsulinemic ( p < 0.05) and hyperglucagonemic ( p < 0.001 ) as compared to control group. Three patients with hyperosmolar hyperglycemic non-ketotic diabetes, 1 male and 2 females, were hyperglycemic ( p < 0.001 ). Eight patients with uncontrolled type I diabetes mellitus, 6 males and 2 females, were having hyperglycemia (p< 0.001) along with hyperglucagonemia (p < 0.001). Twelve patients with uncontrolled type 2 diabetes mellitus, 6 males and 6 females, were found to be hyperglycemic ( p < 0.001 ) and hyperinsulinemic (p < 0.001) as compared to control group. The insulin / glucagon ratio was found to be 1 : 0.9 in diabetic ketoacidosis, 1: 0.15 in hyperosmolar hyperglycemic non-ketotic diabetes, 1: 0.24 in type 1 diabetics, 1: 0.08 in type 2 diabetics, and 1: 0.1 in the control group. It was concluded that if insulin / glucagon ratio in type 2 diabetics reduces to 1: 0.9 then these patients may develop ketoacidosis instead of hyperosmolar hyperglycemic non ketotic diabetes. Hence, it is the balance and interplay of insulin and glucagon which predicts the type of acute hyperglycemic emergencies (diabetic ketoacidosis and hyperosmolar hyperglycemic non-ketotic diabetes ) being observed in diabetic patients and not the type of diabetes mellitus.

Genetic Analysis of Clinical Mastitis, Milk Fever, Ketosis, and Retained Placenta in Three Lactations of Norwegian Red Cows

The objectives were to infer heritability and genetic correlations between clinical mastitis (CM), milk fever (MF), ketosis (KET), and retained placenta (RP) within and between the first 3 lactations and to estimate genetic change over time for these traits. Records of 372,227 daughters of 2411 Norwegian Red (NRF) sires were analyzed with a 12-variate (4 diseases×3 lactations) threshold model. Within each lactation, absence or presence of each of the 4 diseases was scored based on the cow's health recordings. Each disease was assumed to be a different trait in each of the 3 lactations. The model for liability had trait-specific effects of year-season of calving and age of calving (first lactation) or month-year of calving and calving interval (second and third lactations), herd-5-yr, sire of the cow, and a residual. Posterior means of heritability of liability in first, second, and third lactations were 0.08, 0.07, and 0.07, respectively, for CM; 0.09, 0.11, and 0.13 for MF; 0.14, 0.16, and 0.15 for KET, and 0.08 in all 3 lactations for RP. Posterior means of genetic correlations between liability to CM, MF, KET, and RP, within disease between lactations, ranged from 0.19 to 0.86, and were highest between KET in different lactations. Correlations involving first lactation MF were low and had higher standard deviations. Genetic correlations between diseases were low or moderate (from −0.10 to 0.40), within as well as between lactations; the largest estimates were for MF and KET, and the lowest involved MF or KET and RP. Positive genetic correlations between diseases suggest that some general disease resistance factor with a genetic component exists. Trends of average sire posterior means by birth-year of daughters were used to assess genetic change, and the results indicated genetic improvement of resistance to CM and KET and no genetic change for MF and RP in the NRF population.

Genetic Selection for Health Traits Using Producer-Recorded Data. II. Genetic Correlations, Disease Probabilities, and Relationships with Existing Traits

The objectives of this study were to calculate genetic correlations between health traits that were recorded in on-farm herd management software programs and to assess relationships between these traits and other traits that are routinely evaluated in US dairy sires. Data consisted of 272,576 lactation incidence records for displaced abomasum (DA), ketosis (KET), mastitis (MAST), lameness (LAME), cystic ovaries (CYST), and metritis (MET) from 161,622 cows in 646 herds. These data were collected between January 1, 2001 and December 31, 2003 in herds using the Dairy Comp 305, DHI-Plus, or PCDART herd management software programs. Binary incidence data for all disorders were analyzed simultaneously using a multiple-trait threshold sire model that included random sire and herd-year-season of calving effects. Although data from multiple lactations were available for some animals, our genetic analysis included only first parity records due to concerns about selection bias and improper modeling of the covariance structure. Heritability estimates for the presence or absence of each disorder during first lactation were 0.14 for DA, 0.06 for KET, 0.09 for MAST, 0.03 for LAME, 0.04 for CYST, and 0.06 for MET. Estimated genetic correlations were 0.45 between DA and KET, 0.42 between KET and CYST, 0.20 between MAST and LAME, 0.19 between KET and LAME, 0.17 between DA and CYST, 0.17 between KET and LAME, 0.17 between KET and MET, and 0.16 between LAME and CYST. All other correlations were negligible. Correlations between predicted transmitting abilities for the aforementioned health traits and existing production, type, and fitness traits were low, though it must be noted that these estimates may have been biased by low reliability of the health trait evaluations. Based on results of this study, it appears that genetic selection for health disorders recorded in on-farm software programs can be effective. These traits can be incorporated into selection indices directly, or they can be combined into composite traits, such as “reproductive disorders”, “metabolic disorders”, or “early lactation disorders”.

Genetic Selection for Health Traits Using Producer-Recorded Data. I. Incidence Rates, Heritability Estimates, and Sire Breeding Values

The objective of this study was to determine the feasibility of genetic selection for health traits in dairy cattle using data recorded in on-farm herd management software programs. Data regarding displaced abomasum (DA), ketosis (KET), mastitis (MAST), lameness (LAME), cystic ovaries (CYST), and metritis (MET) were collected between January 1, 2001 and December 31, 2003 in herds using Dairy Comp 305, DHI-Plus, or PCDART herd management software programs. All herds in this study were either participants in the Alta Genetics (Watertown, WI) Advantage progeny testing program or customers of the Dairy Records Management Systems (Raleigh, NC) processing center. Minimum lactation incidence rates were applied to ensure adequate reporting of these disorders within individual herds. After editing, DA, KET, MAST, LAME, CYST, and MET data from 75,252 (313), 52,898 (250), 105,029 (429), 50,611 (212), 65,080 (340), and 97,318 (418) cows (herds) remained for analysis. Average lactation incidence rates were 0.03, 0.10, 0.20, 0.10, 0.08, and 0.21 for DA, KET, MAST, LAME, CYST, and MET (including retained placenta), respectively. Data for each disorder were analyzed separately using a threshold sire model that included a fixed parity effect and random sire and herd-year-season of calving effects; both first lactation and all lactation analyses were carried out. Heritability estimates from first lactation (all lactation) analyses were 0.18 (0.15) for DA, 0.11 (0.06) for KET, 0.10 (0.09) for MAST, 0.07 (0.06) for LAME, 0.08 (0.05) for CYST, and 0.08 (0.07) for MET. Corresponding heritability estimates for the pooled incidence rate of all diseases between calving and 50 d postpartum were 0.12 and 0.10 for the first and all lactation analyses, respectively. Mean differences in PTA for probability of disease between the 10 best and 10 worst sires were 0.034 for DA, 0.069 for KET, 0.130 for MAST, 0.054 for LAME, 0.039 for CYST, and 0.120 for MET. Based on the results of this study, it appears that genetic selection against common health disorders using data from on-farm recording systems is possible.