Economic and environmental effects of double cropping winter annuals and corn using the Integrated Farm System Model.

Dairy farms have been under pressure to reduce negative environmental impacts while remaining profitable during times with volatile milk and commodity prices. Double cropping has been promoted to reduce negative environmental impacts and increase total dry matter yield per hectare. Three dairy farms that double cropped winter annuals and corn were selected from northern and western Pennsylvania. Data were collected from recorded crop and dairy records and financial data for 2016 and 2017. Farms ranged in size from 336 to 511 ha with 233 to 663 cows. Data were used to set parameters for the Integrated Farm System Model, which was then used to simulate 8 scenarios for each farm: current operation; 0, 50, and 100% of corn hectares double cropped; 30% feed price increase with and without double cropping; and 30% feed price decrease with and without double cropping at the farm's current level of double cropping. A 20-yr time period, using weather data that was representative of the actual farms, was used in the Integrated Farm System Model simulation to produce both financial and environmental outputs. Double cropping winter annuals and corn silage increased dry matter yield per hectare by 19%, when comparing 0 to 100% of the corn area double cropped. With all corn land double cropped, net return to management per hundredweight (45.36 kg) of milk increased by 1.8%, N leached per hectare per year decreased by an average of 4.5%, and phosphorus loss was reduced by an average of 9.2% across farms. When feed prices increased by 30%, double cropping increased net return over feed cost and net return to management by 1.6 and 2.2%, respectively, across farms. When feed prices decreased by 30%, double cropping decreased net return over feed cost and net return to management by smaller amounts of 0.13% and 0.11%, respectively, across farms. Modeling indicated that double cropping winter annuals with corn silage can have both environmental and economic benefits when winter-annual silage yields are enough to cover expenses.

Evaluating the effect of ration composition on income over feed cost and milk yield.

Feed is generally the greatest expense for milk production. With volatility in feed and milk markets, income over feed cost (IOFC) is a more advantageous measure of profit than simply feed cost per cow. The objective of this study was to evaluate the effects of ration cost and ingredient composition on IOFC and milk yield. The Pennsylvania State Extension Dairy Team IOFC tool (http://extension.psu.edu/animals/dairy/business-management/financial-tools/income-over-feed-cost/introduction-to-iofc) was used to collect data from 95 Pennsylvania lactating dairy cow herds from 2009 to 2012 and to determine the IOFC per cow per day. The data collected included average milk yield, milk income, purchased feed cost, ration ingredients, ingredient cost per ton, and amount of each ingredient fed. Feed costs for home-raised feeds for each ration were based on market values rather than on-farm cost. Actual costs were used for purchased feed for each ration. Mean lactating herd size was 170 ± 10.5 and daily milk yield per cow was 31.7 ± 0.19 kg. The mean IOFC was $7.71 ± $1.01 cost per cow, ranging from -$0.33 in March 2009 to $16.60 in September 2011. Data were analyzed using a one-way ANOVA in SPSS (IBM Corp., Armonk, NY). Values were grouped by quartiles and analyzed with all years combined as well as by individual year. Purchased feed cost per cow per day averaged $3.16 ± $1.07 for 2009 to 2012. For 2009 to 2012 combined, milk yield and IOFC did not differ with purchased feed cost. Intermediate levels (quartiles 2 and 3) of forage cost per cow per day between $1.45 and $1.97 per cow per day resulted in the greatest average IOFC of $8.19 and the greatest average milk yield of 32.3 kg. Total feed costs in the fourth quartile ($6.27 or more per cow per day) resulted in the highest IOFC. Thus, minimizing feed cost per cow per day did not maximize IOFC. In 2010, the IOFC was highest at $8.09 for dairies that fed 1 or more commodity by-products. Results of the study indicated that intermediate levels of forage cost and higher levels of total feed cost per cow per day resulted in both higher milk yield and higher IOFC. This suggests that optimal ration formulation rather than least cost strategies may be key to increasing milk yield and IOFC, and that profit margin may be affected more by quality of the feed rather than the cost.

Relationships between selected human resource management practices and dairy farm performance.

The objectives were to identify relationships between human resource management (HRM) practices used by dairy farm businesses and the productivity and profitability of the dairies. Explanatory variables were the following practices: training, job descriptions, standard operating procedures, milk quality incentives, and the employment of Spanish-speaking employees. The dependent variables were return on assets, return on equity, rolling herd average, and somatic cell count. The effects of individual HRM practices were analyzed to test for means separation between groups that "used" and those that "did not use" HRM practices. The results did not support expectations that differences exist between the groups. However, a significant positive relationship was found between return on equity and the use of continued training (used = 10.61%; did not use = -62.38%), and a significant negative relationship was found between the use of standard operating procedures for feeding and somatic cell count (used = 263,000; did not use = 214,000). Profitability and productivity did not seem to be major factors in producers' decisions to use or not use HRM practices.

Supplemental carbohydrate sources for lactating dairy cows on pasture.

Two experiments were conducted to evaluate steam-flaked corn and nonforage fiber sources as supplemental carbohydrates for lactating dairy cows on pasture. Cows were allotted to a new paddock of an orchardgrass (Dactylis glomerata L.) pasture twice daily in one group in both trials. In experiment 1, 28 Holstein cows, averaging 216 d in milk, were randomly assigned to either a cracked-corn (CC) or a steam-flaked (SFC) supplement in a split plot design. The supplement contained 66.7% of corn and a protein/mineral pellet. In experiment 2, 28 Holstein cows, averaging 182 d in milk, were randomly assigned to either a ground corn (GC) or a nonforage fiber (NFF)-based supplemented in a single reversal design. The GC supplement contained 85% ground corn plus protein, mineral, and vitamins. The NFF supplement contained 35% ground corn, 18% beet pulp, 18% soyhulls, 8% wheat middlings plus protein, mineral, and vitamins. In both experiments, cows were fed the grain supplement twice daily after each milking at 1 kg/4 kg milk. In experiment 1, milk production (24.3 kg/d) and composition did not differ between treatments; however, plasma and milk urea N were lower with the SFC supplement. In experiment 2, milk production (27.5 kg/d) was not affected by treatments, which may be related to the medium quality of pasture grazed. The GC supplement tended to reduce plasma and milk urea N and increased milk protein percentage (3.23 vs. 3.19%). Pasture dry matter intake, measured using Cr2O3, did not differ between treatments in either experiment 1 (15.1 kg/d) or experiment 2 (12.2 kg/d). Milk production did not differ when mid-late lactation cows on pasture were supplemented with SFC or NFF instead of dry corn.

Lymphocyte proliferation response of lactating dairy cows fed varying concentrations of rumen-protected methionine.

Six midlactation Holstein cows were used in a replicated 3 x 3 Latin square design to characterize the influence of dietary concentration of Mepron 85 (Degussa Corp., Allendale, NJ) on isolated mononuclear cell composition and lymphocyte proliferation. Cows were fed a common total mixed ration containing corn silage, legume silage, chopped legume hay, and a grain and mineral pellet that was top-dressed with one of three treatments. Treatments consisted of 1) 0 g/d of Mepron 85, 2) 15 g/d of Mepron 85 (11 g of rumen-protected Met), or 3) 30 g/d of Mepron 85 (22 g of rumen-protected Met). Cows were housed in a tie-stall barn, had continuous access to fresh water, and were fed once daily at 0900 h for ad libitum intake. Dry matter intake (DMI), orts, and milk yields were recorded daily, and weekly milk samples were collected for analyses of fat, protein, SCC, and milk urea nitrogen. Blood and milk samples were collected before the beginning of the experiment and during wk 2 and 4 of each 28-d treatment period. Blood was analyzed for serum methionine, lymphocyte proliferation, and phenotypic composition of isolated mononuclear cells. Milk samples were analyzed for phenotypic composition of isolated mononuclear cells. Least square means for DMI, milk yield, milk composition, and phenotypic mononuclear cell composition of blood and milk were not affected by treatment. Proliferative ability of peripheral blood T lymphocytes increased for cows consuming 30 g/d of Mepron 85.

Comparison of methods of in vitro dry matter digestibility for ten feeds.

The objectives were to determine if the in vitro dry matter (DM) digestibility was similar by using a traditional method compared to the new DAISYII system and to determine if in vitro DM digestibility was similar for sources of inoculum from two different donor cow diets, all forage or total mixed ration. Ten feeds were digested by the traditional method, the DAISYII method with same feeds in a digestion vessel, and the DAISYII method with different feeds in a digestion vessel. The study used a 2 x 3 factorial arrangement of treatments with two sources of inoculum and three methods. The study was replicated. Source of inoculum affected in vitro DM digestibility; the grass hay donor cow diet resulted in lower digestibility values in six of the 10 feeds tested. Method did not significantly affect the digestibility values, and there were no significant source by method interactions. The DAISYII method can be used to increase labor efficiency in the in vitro DM digestibility analysis, and forages and grains can be analyzed together in a single digestion vessel.

Dry matter intake and milk yield and composition of cows fed yeast prepartum and postpartum.

Thirty-six multiparous and 12 primiparous Holstein cows were utilized in a completely randomized design to characterize the effects of feeding yeast cultures (Saccharomyces cerevisiae) and enzymes on dry matter intake and milk yield and composition. The prepartum diet consisted of a total mixed ration containing chopped grass hay, corn silage, and grain pellet. The postpartum diet consisted of a total mixed ration containing corn silage, legume silage, chopped legume hay, and grain pellet. Treatments consisted of 1) whey control, 10 g/d; 2) enzyme, 10 g/d; 3) yeast; 15 g/d; and 4) Biomate Yeast Plus (20 g/d; Chr. Hansen BioSystems, Inc., Milwaukee, WI). Treatments were top-dressed at feeding time. Cows were housed in a tie-stall barn, had continuous access to fresh water, and were fed once daily at 0800 h for ad libitum intake. Daily intake and orts were recorded beginning 28 d prior to the expected calving date through wk 13 of lactation. Daily milk yield and weekly milk samples were collected through wk 13 of lactation. Body weight and body condition score were recorded once every 2 wk throughout the experiment. Urine samples were collected at 30, 60, and 90 d of lactation and were analyzed for allantoin and creatinine. Least squares means for intake, milk yield, and milk composition were unaffected by treatment. The allantoin to creatinine ratio was not affected by treatment. Yeast cultures with or without enzyme had no direct effects on prepartum or postpartum dry matter intake or milk yield and composition.

Effects of ageing on spatial aspects of the pattern electroretinogram in male and female quail.

This study deals with age-related functional changes in the eye of quail. Measurements of lens refractive state and transmission, as well as pupil diameter, showed that the quail's eye became more myopic with increasing age, but no change could be detected in lens transmission and pupil diameter. Three aspects of the pattern electroretinogram (PERG) were studied after correcting for ocular refraction: (i) spatial characteristics (visual acuity and contrast sensitivity); (ii) maximal amplitude; and (iii) peak latency. The PERG results suggested that the visual acuity was age-independent for both sexes. However, the contrast sensitivity of the old quail (16-20 months) was much lower (1.5-3 times) than that of the young (3-6 months) at low to intermediate (< 2 c/d), but not at high spatial frequencies. The peak latency of the PERG response was 3-4 msec longer in the old birds compared with the young, while the maximal amplitude of the PERG response was age-independent. These results clearly suggested that at least some of the age-induced changes are located in the neural retina.

Determination of trazodone and its metabolite, 1-m-chlorophenyl-piperazine, in human plasma and red blood cell samples by HPLC.

OBJECTIVES: To develop an HPLC method for the analysis of trazodone and its metabolite, 1-m-chlorophenyl-piperazine (m-CPP), in human plasma and red blood cells. DESIGN AND METHODS: The analytes were extracted by heptane containing 1.5% isoamyl alcohol, back extracted into phosphoric acid and analyzed by reverse phase HPLC with UV detection. RESULTS: In seven randomly selected, male, human subjects plasma concentrations (nmol/l) were 380-5841 for trazodone and 14-237 for m-CPP while those in packed red blood cells were 98-634 for trazodone and 15-155 for m-CPP. Plasma trazodone concentrations were 4-11-fold higher than those in red blood cells while those of m-CPP were about equal. This may be the first report on concentrations of trazodone and m-CPP in human red blood cells. CONCLUSIONS: This sensitive method can be used for monitoring trazodone and m-CPP in human plasma and red blood cells.

Effect of corn silage supplementation on intake and milk production in cows grazing grass pasture.

The objective was to determine the effects on milk production and DMI of 2.3 kg/d of corn silage DM fed to lactating cows grazing grass pasture and fed supplemental grain. Thirty Holstein cows, averaging 32 kg of milk at the start of the trial, intensively grazed grass pasture for 8 wk. One-half of the cows received 2.3 kg/d of corn silage DM in two equal feedings, and one-half of the cows were used as controls (no corn silage). All cows were fed grain at 1 kg of grain DM/4 kg of milk. Corn silage had no effect on milk production or milk composition. Cows fed corn silage did not have improved BW gain or body condition score. Each unit of corn silage consumed replaced 1.2 units of pasture, but total DMI was not different because of supplementation with corn silage. Blood urea N concentrations were lower for cows fed corn silage. Supplementation of high producing Holsteins grazing grass pastures with 2.3 kg/d of corn silage DM had no effect on milk production, milk composition, or total DMI.

Ruminal digestion and duodenal nutrient flows in dairy cows consuming grass as pasture, hay, or silage.

The objective of this experiment was to quantitate ruminal digestion and flow of nutrients to the small intestine of Holstein cows grazing grass pasture or fed grass hay or silage. Three dry, nonpregnant Holstein cows fitted with ruminal and duodenal (Y-type) cannulas grazed or were given free choice access to hay or silage during three consecutive 19-d periods. Pasture intake was estimated using chromic oxide; hay and silage intakes were both measured and estimated. Intakes were similar among forages. Ruminal samples had higher VFA and ammonia when cows grazed than when cows were fed hay or silage. Ruminal pH did not differ. Based on duodenal spot sampling, cows on pasture had lower DM flows to the small intestine. Bacterial N flow, as a percentage of total N flow, was higher for cows that grazed. Most flows of AA to the small intestine were similar among forages, but Pro and Phe were lower for grazing cows. Supplementation strategies for cows on pasture should be designed to synchronize protein and carbohydrate in the rumen and to increase the supply of nutrients available in the small intestine.

Effects of alfalfa and orchardgrass on digestion by dairy cows.

The effects of alfalfa and orchardgrass diets of similar NDF content on ruminal digestion and digesta kinetics as measured using radiolabeled herbage were evaluated in Holstein cows. Two dry and two lactating cows, fitted with ruminal and duodenal cannulas, were fed 12 times daily at restricted and ad libitum intakes, respectively, in a crossover design. Diets were 65:35 and 55:45 hay: concentrate in DM for alfalfa and orchardgrass, respectively, with approximately 19% CP and 42% NDF. The DMI by lactating cows was greater for the alfalfa diet than for the orchardgrass diet. Ruminal and apparent total tract digestibilities of NDF and ADF were less for cows consuming the alfalfa diet than for those on the orchardgrass diet. Particle size of ruminal digesta, based on specific activity from a ruminal pulse-dose of 14C-labeled alfalfa or orchardgrass, did not decrease consistently with time and was greater than fecal particle size, suggesting selective retention of large digesta particles before passage. Ruminal and total tract fractional passage rates of indigestible NDF, based on 14C-labeled forage, did not differ as a result of forage or lactation stage, but NDF gut fill was greater in lactating than in dry cows, indicating that changes in gut fill were related more to differences in intake than to passage rate.

Estimation of intake in high producing Holstein cows grazing grass pasture.

The objectives were to estimate intake of pasture and total DMI by high producing cows grazing grass pastures and to measure changes in nutrient composition of grass pasture during the grazing season. Sixteen multiparous Holstein cows averaging 31 kg of 4% FCM/d at the start of the trial grazed grass pastures at a stocking rate of 2.5 or 3.9 cows/ha from April until October 1990. Intake was estimated using Cr2O3 as an indigestible fecal marker. Pasture samples were analyzed for nutrient composition at six times during the grazing season corresponding to the times of intake estimation. Total daily DMI increased from 21.3 kg in early spring to 22.4 kg in late spring and then decreased as lactation progressed; however, DMI exceeded NRC recommendations during most of the grazing season. Daily pasture DMI varied with season, ranging from 11.6 to 15.6 kg and was lowest (11.6 kg) in the summer. Estimated NEL intakes were lower than NRC recommendations in early spring. During the grazing season, pasture ranged from 39 to 48% NDF and from 22 to 30% CP with 15 to 20% ruminally degradable protein on a DM basis. Grazing cows consumed adequate DM from pasture except in early spring. Although nutrient composition of pasture varied with season, quality remained high.

Quality evaluation and concentrate supplementation of rotational pasture grazed by lactating cows.

The effects of pasture quality and the amount and nutrient composition of a concentrate supplement on performance of lactating cows were investigated under a controlled rotational grazing system. Pasture samples were collected for two consecutive summers, and the relationship was positive between wet chemistry and near infrared reflectance spectroscopy for CP, ADF, and NDF. During yr 2, 54 Holstein cows averaging 82 d postpartum were used in a randomized block design to evaluate three methods of supplementing grain for a 24-wk trial. A 16.2-ha area of primarily orchardgrass pasture was divided into paddocks of approximately .40 ha each. The three supplemental grain rations were: 1) 1 kg of grain/3 kg of milk; 2) 1 kg of grain/4 to 5 kg of milk adjusted weekly, depending upon the quantity of pasture available; and 3) 1 kg of grain/4 to 5 kg of milk. The amount fed in ration 3 was adjusted weekly, depending upon the quantity of pasture available, and reformulated biweekly based on analysis of pasture. No differences existed among treatments for milk production (24.7, 23.2, and 24.1 kg/d) or 3.5% FCM (25.3, 24.8, and 24.9 kg/d) over the 24-wk trial. Cows fed more grain (ration 1) gained more BW. Adjusting nutrient density of the grain to changes in pasture quality resulted in similar milk production and a lower ration cost.

Resolution of the interference from carbamazepine and diphenhydramine during reversed-phase liquid chromatographic determination of haloperidol and reduced haloperidol.

Carbamazepine and diphenhydramine interfered with the assays of haloperidol and its metabolite, reduced haloperidol, by reversed-phase HPLC. Retention times of haloperidol, reduced haloperidol, and the interfering drugs were very sensitive to the percentage of potassium phosphate buffer in the mobile phase as well as to the final pH of the eluant. Retention times were not very dependent upon ionic strength of the eluting solvent mixture. Haloperidol and reduced haloperidol in the range of 0.5-10 ng/mL were analyzed in the presence of 0.2 micrograms/mL diphenhydramine and 5 micrograms/mL of carbamazepine. The concentrations of all drugs used were in their expected therapeutic ranges. The isocratic chromatographic conditions were as follows: 25-cm x 4.6-mm C-18 column; mobile phase, 75% phosphate buffer (final concentration, 0.06M) and 25% acetonitrile; final pH, 3.5; flow rate, 2.5 mL/min; and detection by UV absorption at 220 nm. Additional changes in the percent buffer in the mobile phase may be useful in achieving separation of other interfering compounds.