Biomedical subjects

L E Chase

Publications and source records attributed to L E Chase.

At least 19 recordsLinked to original sources

PubMed2006

Major advances in extension education programs in dairy production.

The dairy industry has seen structural changes in the last 25 yr that have an impact on extension programming. The number of cows in the United States has decreased by 17%, whereas the number of dairy farms has decreased by 74%. The average milk production per cow has increased from 5,394 to 8,599 kg/lactation. Even though there are fewer farms, dairy farm managers are asking for more specific and targeted information. The extension resources available have also decreased during this period. Because of these changes, shifts have taken place in extension programming and staffing. A key change has been a shift to subject matter-targeted programs and workshops. Extension has also incorporated and expanded use of the Internet. Discussion groups, subject matter courses, and searchable databases are examples of Internet use. There will be continuing shifts in the demographics of the US dairy industry that will influence future extension efforts. It is also probable that fewer extension professionals will be available to provide programming due to changes in funding sources at national, state, and local levels. Future shifts in extension programming will be needed to provide the information needs of the industry with a smaller number of extension workers.

Animals↗

PubMed2004

Lactation performance of holstein cows fed fescue, orchardgrass, or alfalfa silage.

Perennial grasses are increasingly being used as an integral part of nutrient management plans, but fescue (Festuca arundinacea Schreb.) is often overlooked because of perceived intake problems. A 30-d study was conducted to evaluate the lactation performance of cows fed a fescue silage-based total mixed ration (TMR) compared with orchardgrass (Dactylis glomerata L.) and alfalfa (Medicago sativa L.) silage-based TMR, when forages are harvested at recommended neutral detergent fiber (NDF) levels. Holstein cows (body weight [BW] = 627 +/- 66.0 kg, milk yield = 40.9 +/- 6.93 kg/d, parity = 2.6 +/- 1.44, days in milk = 152 +/- 24.5) were randomly assigned to treatment. Statistical design was a randomized complete block with 10 cows per treatment. The 5 treatments consisted of TMR using first-cutting alfalfa, and first- and second-cutting orchardgrass and tall fescue silage. Diets were formulated to provide 0.95% of BW as forage NDF and contained approximately 18% CP and 1.6 mcal/kg. This resulted in diets of about 30% NDF; for a 612-kg cow, approximately 5.8 kg/d of forage NDF was fed. Second-cutting, grass-based TMR had lower intake than alfalfa and first-cutting forage TMR. Cows consuming second-cutting orchardgrass had lower milk production than did cows consuming other forage TMR. Cows fed fescue TMR had higher milk production than those fed orchardgrass. Indigestible residues were higher, and NDF digestibilities were lower, in second-cutting forages vs. first-cutting forages, likely contributing to the differences observed in intake and resulting differences in milk production. Dairy cows consumed the first-cutting fescue TMR readily and performed as well as those on alfalfa or first-cutting, orchardgrass-based TMR in terms of lactation performance, but fescue and orchardgrass rations will require more concentrate in the ration than alfalfa.

Animal Nutritional Physiological Phenomena↗

PubMed2004

Phosphorus reduction through precision feeding of dairy cattle.

A study was conducted on 4 dairy farms in the Cannonsville Reservoir Basin (Delaware County, NY) to identify feeding strategies in commercial dairy herds that will reduce manure phosphorus and mass farm phosphorus balance. Lactating cow diets on all 4 farms were evaluated monthly for 28 mo using the Cornell Net Carbohydrate and Protein System. Milk production and herd reproductive performance were measured monthly. Manure phosphorus content was measured every 6 mo. Reduced phosphorus diets (precision feeding) were implemented in 2 of the herds. Mean herd phosphorus intakes in the 4 herds ranged from 107 to 165% of requirement. Dietary phosphorus intakes in the 2 herds where diets were modified were reduced from 153% of requirement to 111%, an average reduction of 25%. Predicted phosphorus intakes and manure excretions were reduced 11.8 kg/yr per cow. After dietary adjustments in the 2 herds, fecal phosphorus concentrations decreased 33%. Milk production was not adversely affected by reduced phosphorus diets. Whole farm mass phosphorus balances (amount of phosphorus remaining on the farm) on the 2 farms were reduced 49%, with the percentage of imported phosphorus remaining on the farm reduced to less than 45%. Achieving feed phosphorus reductions similar to those of this study on all of the estimated 7000 to 8000 mature dairy cattle in the Cannonsville Basin could reduce feed phosphorus imports and manure phosphorus excretions more than 64,000 kg/yr. This would slow the rate of phosphorus accumulation in agricultural soils in the Cannonsville Basin, which over time could reduce the 50,000 kg/yr average total phosphorus loading of the Cannonsville Reservoir.

Animal Feed↗

PubMed2003

Phosphorus feeding levels and critical control points on dairy farms.

A viable and cost-effective approach to managing P on dairy farms is to minimize excess P in diets, which in turn leads to less excretion of P in manure without impairing animal performance. A questionnaire survey was conducted, coupled with on-site feed and fecal sample collection and analysis on dairy farms in New York, Pennsylvania, Delaware, Maryland, and Virginia. The purpose was to assess dietary P levels and to identify critical control points pertaining to P feeding management. Survey responses, 612 out of 2500 randomly selected farms, revealed a wide range of dietary P concentrations for lactating cows, from 3.6 to 7.0 g/kg of feed DM. The mean was 4.4 g/kg, which was 34% above the level recommended by the NRC for 27.9 kg milk/d, the mean milk yield in the survey. Higher P concentrations in diets were not associated with higher milk yields (n = 98, R2 = 0.057 for the survey farms; n = 92, R2 = 0.043 for farms selected for on-site sampling). However, higher dietary P led to higher P excretion in feces (n = 75, R2 = 0.429), with much of the increased fecal P being water soluble. Phosphorus concentrations in diet samples matched closely with P concentrations in formulated rations, with 67% of the feed samples deviating <10% from the formulations. On 84% of the survey farms, ration formulation was provided by professionals rather than producers themselves. Most producers were feeding more P than cows needed because it was recommended in the rations by these consultants. In conclusion, P fed to lactating cows averaged 34% above NRC recommendations; to reduce excess dietary P, ration formulation is the critical control point.

Animal Feed↗

PubMed2003

Influence of dietary nonfiber carbohydrate concentration and supplementation of sucrose on lactation performance of cows fed fescue silage.

There is interest in knowing if the source of nonfibrous carbohydrates (NFC) influences milk production and composition. Our objective was to determine the effects of source (starch or sugar) and level of NFC in the diet on these parameters. A 4 x 4 Latin square replicated five times using early-lactation (56 +/- 9 DIM) Holstein cows was used; cows were offered one of two levels of NFC and either no added sucrose or sucrose substituting for 10% of the corn. Diets were balanced to meet National Research Council requirements for total protein, energy, and minerals. Tall fescue silage was included at one of two levels (0.95 or 1.25% of BW as forage NDF), resulting in diets with 40 and 30% NFC. The remaining ingredients consisted of high-moisture corn, soybean meal, SoyPlus, minerals, and vitamins. Megalac (0.45 kg) was used in the low NFC diets. High NFC diets were lower (P < 0.01) in neutral detergent fiber (NDF; 31.5%) and crude protein (CP; 19.6%) than the low NFC diet (35.8% NDF and 21.0% CP). Sucrose containing diets were somewhat lower (P < 0.01) in NDF (33.1%) than the no sucrose added diets (34.3%), but diets did not differ in CP%. Cows offered the high NFC level produced more milk (39.6 kg/d; P < 0.05) than those offered the low level (38.3 kg/d), primarily due to higher dry matter intake (P < 0.05). Cows consuming the high NFC diet also had lower (P < 0.05) milk fat (3.25%) and milk urea nitrogen (MUN; 13.7 mg/dl), and higher (P < 0.05) milk protein (2.58%) and milk lactose (4.81%) concentrations than cows offered the low NFC level (3.46% milk fat, 17.5 mg/dl MUN, 2.51% milk protein, and 4.74% milk lactose). Fat yield was higher (P < 0.05) for cows fed low NFC diets than cows fed high NFC diets, whereas protein and fat yield were lower (P < 0.05) for cows fed low NFC diets than those fed high NFC diets. The NFC source did not influence dry matter intake or milk production or milk component yield (P > 0.05). Milk lactose (4.79%) and MUN (16.0 mg/dl) concentrations were higher (P < 0.05) for cows offered sucrose as a portion of the NFC compared with those not offered sucrose (4.76% milk lactose and 15.2 mg/dl MUN). Results suggest that cows fed sucrose may utilize diet nitrogen less efficiently than those not fed sucrose, when sucrose is replacing a portion of the high-moisture corn in the diet.

Animals↗

PubMed2002

Digestibility by dairy cows of monosaccharide constituents in total mixed rations containing citrus pulp.

Ten lactating cows were divided into two groups and individually fed ad libitum one of two experimental total mixed rations (TMR) as follows: 1) a TMR containing 20% corn grain and 10% dry citrus pulp (high corn); and 2) a TMR containing 21% citrus pulp and 9% corn grain (high citrus pulp). Both TMR also contained corn silage (28%), legume haylage (19.5%), extruded full fat soybeans (13.5 to 14%), soybean meal (6.5%), and minerals and vitamins. Voluntary dry matter intake of cows consuming the high corn ration tended to be higher than for cows in the high citrus pulp group (22.2 vs. 20.7 +/- 1.0 kg/cow per day, respectively). Digestibility of NDF was higher for the TMR with high citrus pulp compared with the TMR with higher corn. Across treatments, neutral detergent fiber (NDF) glucose was more digestible than NDF xylose and uronic acids and less digestible than NDF arabinose, galactose, and mannose. Digestibility of total neutral detergent soluble carbohydrates was also higher in the high citrus pulp group (86.8, high citrus pulp vs. 80.3 +/- 1.7%, high corn); with glucose and uronic acids accounting for most of that difference. Consequently, higher total carbohydrate digestibility was obtained in the TMR containing higher citrus pulp compared with the TMR with a higher percentage of corn (77.1 and 72.5 +/- 1.0%, respectively). Slightly lower carbohydrate intake in cows fed higher citrus pulp was compensated by higher digestibility of carbohydrates and protein. Thereby, partial replacement of corn by citrus pulp in TMR of high producing dairy cows improved feed efficiency.

Animal Feed↗

PubMed2000

The effect of nonstructural carbohydrate and addition of full fat extruded soybeans on the concentration of conjugated linoleic acid in the milk fat of dairy cows.

Conjugated linoleic acid (CLA), a naturally occurring anticarcinogen found in dairy products, is a byproduct of incomplete ruminal biohydrogenation of unsaturated fatty acids. Our objective was to determine the effect of nonstructural carbohydrate sources, addition of full fat extruded soybeans as a source of unsaturated fatty acids, and possible interactions on the milk fat content of CLA. Cows (n = 20) were assigned to a 4 x 4 Latin square involving two sources of nonstructural carbohydrate, high starch (corn) or high pectin (citrus pulp), with or without addition of extruded soybeans. Milk yield was not affected by nonstructural carbohydrate source, but milk production was increased by 7.8 to 10.5% with dietary additions of extruded soybeans. Milk fat content did not differ between treatments, but fatty acid composition was affected. Cows fed extruded soybean diets had reduced concentrations of C8 to C16 fatty acids and increased concentrations of octadecenoic acids. Diets with extruded soybeans also resulted in more than a doubling in milk fat concentration and yield of CLA. Nonstructural carbohydrate source had only minor effects on CLA, and there was no interaction with extruded soybeans. Milk fat content of trans-C18:1 and CLA were closely related (r2 = 0.77). However, variation among cows was about threefold for each of the diets and rank order of individual cows differed among diets. Overall, we demonstrated that diet modification can be used to alter CLA content of milk fat, but there was substantial individual cow variation for all diets.

Animal Feed↗

PubMed2000

Whole-herd optimization with the Cornell Net Carbohydrate and Protein System. I. Predicting feed biological values for diet optimization with linear programming.

We developed a diet optimizer for least-cost diet formulation with the Cornell Net Carbohydrate and Protein System (CNCPS) using linear programming. The CNCPS model is intrinsically nonlinear, and feed biological values vary with animal and feed characteristics. To allow linear diet optimization, we first used the CNCPS model to generate biological values to characterize the energy and protein content of each feed for the specific group for which the diet was being formulated. The biological values used were metabolizable energy (Mcal/kg), metabolizable protein [(% dry matter (DM)], passage rate (%/h), bacteria yield efficiencies (g/g), and degradation rate of the carbohydrate B2 fraction (%/h). In addition, the ruminal balances for nitrogen and peptides were included in the optimizer to optimize ruminal degradation of fiber. The objective function was to minimize diet cost subject to animal requirement and feed availability constraints. The animal constraints were set by requirements for DM intake (kg/d), metabolizable energy (Mcal/kg), metabolizable protein (%DM), and effective neutral detergent fiber (%DM) for a given level of production. Data from a dairy farm were used to evaluate this linear diet optimizer. Across all classes of dairy cattle, the CNCPS 4.0 model typically obtained a solution in less than six iterations that met the requirements with nearly 100% accuracy. We conclude this linear optimizer can be used to accurately formulate least-cost diets with the CNCPS model.

Animals↗

PubMed2000

Whole-herd optimization with the Cornell Net Carbohydrate and Protein System. II. Allocating homegrown feeds across the herd for optimum nutrient use.

The objective of this paper was to develop a linear optimization procedure for allocating homegrown feeds across the herd to optimize use of their nutrients in whole farm nutrient management planning. The first step involved developing an optimal diet for each group by a linear programming (LP) procedure developed for the Cornell Net Carbohydrate and Protein System (CNCPS). Information (feed biological values, nutrient requirements, animal and environmental factors, nutrient excretion, and the optimal diet) for each group was exported to a whole farm worksheet, where another LP procedure was used to optimize the allocation of homegrown crops by satisfying the set requirements of each animal group while optimizing return over feed costs and nutrient excretion constraints. A sample evaluation shows how this model was used to reduce N, P, and K excretion by changing feeding strategies while maintaining return over feed costs.

Animal Feed↗

PubMed2000

Whole-herd optimization with the Cornell Net Carbohydrate and Protein System. III. Application of an optimization model to evaluate alternatives to reduce nitrogen and phosphorus mass balance.

The objectives of this paper were to use a linear programming model previously described to evaluate different alternatives for reducing excess nutrients that may influence water quality on a case study farm (300 lactating cows on 430 ha of cropland growing alfalfa, grass, and corn). Several alternatives perceived to influence farm nutrient balance were evaluated for their potential to reduce N and P mass balance. Dividing lactating cow diets into three groups according to their level of milk production versus a one-group total mixed ration decreased mass balance (tonne/yr) from 51.7 to 44.7 for N, from 6.7 to 6.1 for P and from 16.2 to 14.8 for K with little influence on return over feed costs. Increasing forage quality (lower neutral detergent fiber and higher crude protein) did not improve N balance because of the increased N fixation from the air to the soil, but it increased returns over feed costs by $31,385. Improving yields to the maximum potential for the farm reduced mass balance by 29, 51, and 100% for N, P, and K, respectively, and increased returns over feed costs by $70,579. Changing the crop hectare proportions to more corn and less alfalfa reduced N and K balances by 19 and 29%, respectively, and increased returns over feed costs $39,383. Increasing annual milk production 10% by increasing milk production per head 10% compared with increasing animal numbers at the current average milk production per cow until total milk increased 10% gave $34,132 more return over feed costs with less N, P, and K retained on the farm.

Agriculture↗

PubMed1999

Rate and extent of digestion of the ethanol-soluble and neutral detergent-insoluble fractions of corn grain.

The objectives of this study were to partition corn grain into three digestible fractions and to measure the rate of disappearance of these fractions in vitro. Seventeen corn grain samples with varied fiber concentrations were extracted with either 80% ethanol or neutral detergent to obtain estimates of the pool size and digestion kinetics of the A, B1, B2, and C fractions. The carbohydrate soluble in 80% ethanol averaged only 2.6+/-.3% of the DM, although 80% ethanol extracted 7.1+/-1.2% of DM of corn grain. The ethanol-soluble fraction of corn grain contained protein, ether-extractable compounds, and a small amount of ash in addition to carbohydrate. Because of this chemical heterogeneity and because of the small size of the ethanol-soluble fraction, it was not possible to determine the digestion rate of this fraction by measuring gas production. The NDF content of the corn grain was 10.6+/-.7% of DM and was highly digestible (94.6+/-1.4%). The digestible NDF contributed 9.5% of the total gas production from corn grain. Because the size, digestibility, and digestion rate of the digestible NDF fraction varied little among corn grain samples, it is not necessary to routinely analyze the digestion kinetics of the digestible NDF fraction of dried corn grain. An average gas production curve of this fraction can be used as a base to subtract from the total gas production curve to generate the gas production curve of the neutral detergent-soluble fraction for dried, ground corn grain samples.

Detergents↗

PubMed1998

Evaluation of National Research Council and Cornell Net Carbohydrate and Protein Systems for predicting requirements of Holstein heifers.

This experiment evaluated the effects of prepubertal energy intake and dietary protein source on average daily gain of Holstein heifers. Holstein heifers (n = 273) were assigned to one of three dietary energy treatments that were designed to achieve average daily gains of 0.6, 0.8, and 1.0 kg/d from 90 to 320 kg of body weight. Within each energy treatment, heifers were assigned to diets that were supplemented with animal and plant proteins or plant protein and urea. Diets were formulated using the Cornell Net Carbohydrate and Protein System. Actual mean daily gains by heifers on each energy treatment were 0.68, 0.83, and 0.94 kg/d and were not affected by protein source. Undegradable intake protein was predicted by the Cornell Net Carbohydrate and Protein System to be adequate to support the observed daily gain that was allowed by the amount of energy in the diet and was 13 to 25% lower than the recommendations for undegradable intake protein by the National Research Council. These results suggested that requirements for undegradable intake protein may be met at concentrations that are less than 35% of the dietary crude protein. Energy equations from the National Research Council and Cornell Net Carbohydrate and Protein System were evaluated and accounted for 87 and 86% of the variation in body weight gain that was allowed by the amount of energy in the diet with biases of -7.7 and -5.7%, respectively. The Cornell Net Carbohydrate and Protein System has the primary advantage of improved accuracy in the prediction of nutrient requirements in each unique production situation.

Animal Feed↗

PubMed1998

Effects of three prepubertal body growth rates on performance of Holstein heifers during first lactation.

The effects of body weight (BW) gain, different sources of protein during the prepubertal period (90 to 320 kg of BW), and the performance of Holstein heifers during their first lactation were studied. Heifers (n = 273) were assigned to one of three dietary energy treatments that were designed to achieve average daily gains of 0.6, 0.8, and 1.0 kg/d. Within each energy treatment, different protein sources (plant protein and urea or both plant and animal proteins) were imposed. Actual average daily gains by heifers on each energy treatment were 0.68, 0.83, and 0.94 kg/d for heifers that were fed diets formulated for average daily gains of 0.6, 0.8, and 1.0 kg/d, respectively, which allowed the following ages at first calving: 24.5, 22.0, and 21.3 mo. Breeding was initiated when heifers weighed approximately 340 kg. Protein sources did not affect average daily gain or milk yield. Analysis of the preplanned comparisons of actual 305-d and 4% fat-corrected milk yields indicated that yield was significantly reduced for heifers grown at 0.94 kg/d (9387 and 8558 kg, respectively) compared with that of heifers grown at 0.68 kg/d (9873 and 9008 kg, respectively). However, further regression analysis of fat-corrected milk and residual milk from a test day model on prepubertal BW gain only explained 8 and 2% of the variation in milk yield, respectively. Postcalving BW and body condition score were different among treatments. Posttreatment factors, such as postcalving BW, accounted for more of the variation in milk yield than did prepubertal BW gain. Prepubertal BW gains, when evaluated on a continuum from 0.5 to 1.1 kg/d, explained little of the variation in milk yield; therefore, BW gain during the prepubertal period did not significantly affect milk yield during first lactation.

Adipose Tissue↗

PubMed1997

Evaluation of alternative equations for prediction of intake for Holstein dairy cows.

Six prediction equations for dry matter intake (DMI) were evaluated for accuracy with independent data. The equations were selected based on ease of parameter measurement and practical on-farm use. The equations were assessed for accuracy of predicting individual weekly DMI for primiparous (n = 105) and multiparous (n = 136) cows; three-fourths of these cows were supplemented with a sustained-release form of bovine somatotropin (bST). Large variations in accuracy were identified across the six prediction equations for effects of parity and bST. Prediction accuracy of all equations for cows in wk 1 to 24 of lactation was better for primiparous cows than for multiparous cows. Precision of prediction equations was poor for cows in wk 8 through 12 of lactation and for cows in > 40 wk of lactation. The equation for DMI with the best accuracy measured by a low total lactation mean square prediction error was the modified equation of the National Research Council: DMI (kilograms per day) = -0.293 + 0.372 x fat-corrected milk (kilograms per day) + 0.0968 x body weight 0.75 (kilograms). However, the overall mean bias (predicted minus observed) of the prediction of weekly DMI of a single cow was high for all equations, including the modified equation of the National Research Council. For wk 2, 4, 8, 10, and 20 of lactation, the mean bias for the modified equation was +6, +3.4, -1.3, -2.1, and -2.8 kg/d. The accuracy of prediction was lower for cows treated biweekly with bST. High yielding cows and cows treated biweekly with bST had higher milk yields in relation to body weight, and standardized prediction equations for DMI were less accurate.

Animal Nutritional Physiological Phenomena↗

PubMed1997

Development and evaluation of equations for prediction of feed intake for lactating Holstein dairy cows.

Improved prediction equations for dry matter intake (DMI) of Holstein cows that consume high energy diets were developed using regression techniques applied to a comprehensive database. The equations for predicting DMI, which were dependent on parity, accounted for the effects of milk yield, milk protein, body weight (BW), BW change, days pregnant, ambient temperature, relative humidity, and night cooling. A simplified prediction equation of DMI for farm application was developed and based on milk protein yield and BW at calving. An ambient temperature and a lag adjustment factor for early lactation were developed to improve accuracy of prediction of DMI of dairy cows in early lactation. The developed equations for DMI were evaluated against six independent data files. These equations accounted for 55 to 98% of the variation of the weekly group DMI of the independent validation data. The remainder of the variation in intake was attributed to diet, management, and undescribed animal factors. The equations developed in this study had a mean proportional bias of 5.6% and a mean square prediction error of 5.45 kg2/d. Predicted intake using the new equations was within 3 to 8% of actual intake. The new equations must be applied to situations in which Holstein dairy cows are fed highly digestible diets because dietary fill effects are not considered in these equations. The relationship of milk protein yield and DMI warrants further investigation.

Animal Nutritional Physiological Phenomena↗

PubMed1993

Developing nutrition programs for high producing dairy herds.

Herd average milk production continues to increase in the US. Average milk production in Holstein herds enrolled in DHI testing programs surpassed 9000 kg in some states in 1991. Individual dairy herds have produced > 14,000 kg per cow per lactation. The upper limit for milk production per cow continues to increase. A challenge exists in developing nutrition programs for these herds. The goal is to attain efficient and profitable levels of milk production while maintaining herd health and reproductive performance. Evaluation of rations currently fed to high producing herds indicate that these rations are consistent with current nutrient requirement guidelines. Many high producing herds have average DMI > 4% of BW. Ration formulation principles and nutrient requirements used in development of feeding programs for high producing herds are similar to methods already in use. Optimizing DMI, optimizing rumen fermentation, and providing supplemental nutrients are key factors in meeting tissue nutrient demands in this formulation process.

Animal Feed↗

PubMed1991

Comparison of in vitro techniques to the in situ technique for estimation of ruminal degradation of protein.

The accuracy with which the Streptomyces griseus, ficin, and neutral protease with amylase in vitro methods could be used to predict in situ protein degradation of concentrate feeds was evaluated. Four types of soy products and two types of distillers grains were incubated using each of the four techniques for .5, 1, 2, 4, 8, 12, 24, and 48 h. The percentages of initial CP that remained undegraded over time were determined. Comparison of the degradation curves and contrast analysis of the data indicated that the in vitro methods generated degradability estimates in conflict with those obtained by the in situ method. However, the neutral protease with amylase method ranked the test feeds according to the extent of CP degradation at 24 h most similar to that in situ. Regression equations developed with the neutral protease with amylase degradability estimates explained 78, 76, and 74% of the variation in the in situ estimates obtained after 12, 18, and 24 h of incubation, respectively. At least 69% of the variation in the 18-h in situ estimates could be explained by the neutral protease with amylase estimates obtained after 1, 2, 4, 8, and 12 h of incubation. Little relationship was found between the ficin and S. griseus versus in situ results. Although none of the in vitro methods resulted in degradation curves consistently related to those generated by the in situ technique, relationships were found between protein degradability estimates obtained by the neutral protease with amylase method at specific time points and those obtained by the in situ technique.

Amylases↗

PubMed1990

Relationship of changes in condition score to cow health in Holsteins.

The relationship of body condition score with disease occurrence was examined in 561 cows in nine herds. Cows were body condition scored on a five-point scale (1 = thin, 5 = obese) every 2 wk from drying off until 150 d in milk. Cows scored between 3- and 3+ were considered to be in average or good condition. Cows scored less than or equal to 2+ were considered to be underconditioned, whereas those scored greater than or equal to 4- were considered to be overconditioned. Relationships of health and condition score were examined using multiple logistic regression for dichotomous outcomes (e.g., diseased or healthy). Cows that developed dystocia or were culled lost more condition during the dry period than those that did not develop dystocia or were not culled. Cows overconditioned at drying off were more likely to develop cystic ovarian disease and reproductive problems. Cows underconditioned or overconditioned at drying off were more prone to foot problems after calving. Cows overconditioned at 30 d postpartum were more likely to have metritis.

Animals↗