Ergot alkaloids from endophyte-infected tall fescue decrease reticuloruminal epithelial ABSTRACT: An experiment was conducted to determine if ergot alkaloids affect blood flow to the absorptive surface of the rumen. Steers (n = 8) were pair-fed alfalfa cubes and received ground endophyte-infected (Neotyphodium coenophialum) tall fescue (Lolium arundinaceum; E+) seed (0.015 mg ergovaline·kg BW -1 ·d -1 ) or endophyte-free tall fescue (E-) seed via the rumen cannula 2x daily for 7 d at thermoneutral (TN; 22°C) and heat stress (HS; 32°C) conditions. On d 8, the rumen was emptied and rinsed. A buffer containing VFA was incubated in the following sequence: control (CON), 15 μg ergovaline·kg BW -1 (1×EXT) from a tall fescue seed extract, and 45 μg ergovaline·kg BW -1 (3×EXT). For each buffer treatment there were two 30-min incubations: a 30-min incubation of a treatment buffer with no sampling followed by an incubation of an identical sampling buffer with the addition of Cr-EDTA and deuterium oxide (D 2 O). Epithelial blood flow was calculated as ruminal clearance of D 2 O corrected for influx of physiological water and liquid outflow. Feed intake decreased with dosing E+ seed at HS but not at thermoneutral conditions (TN; P < 0.02). Dosing E+ seed decreased serum prolactin (P < 0.005) at TN. At HS, prolactin decreased in both groups over the 8-d experiment (P < 0.0001), but

The objective was to investigate the effect of intake before fasting on concentrations of metabolites and hormones, respiratory quotient (RQ) and fasting heat production (HP) using the washed rumen technique and to compare these values with those from the fed state. Six Holstein steers (360±22 kg) were maintained at 21°C and fed three different energy intakes within a replicated 3×3 Latin square design with 21-day periods. Steers were fed alfalfa cubes to provide 1.0, 1.5 and 2.0×NEm during 19 days of each experimental period. Steers were placed in individual metabolism stalls fitted with indirect calorimetry head-boxes on day 20 of each experimental period (FED steers) and fed their normal meal. On day 21 of each period the reticulorumen was emptied, washed and refilled with ruminal buffer (NaCl=96; NaHCO3=24; KHCO3=30; K2HPO4=2; CaCl2=1.5; MgCl2=1.5 mmol/kg of buffer) aerated with 75% N2 and 25% CO2 before introduction to the rumen (steers were not fed; WASHED steers). Each gas ex...

Evaluation of a rapid determination of fasting heat production and respiratory ABSTRACT: The objective of this study was to validate use of the washed rumen (WR) technique for rapid measurement of fasting heat production (HP) and respiratory quotient (RQ). Sixteen Holstein steers were divided into 2 groups of 8 for a comparison of measurements made during feeding (both groups; 16 steers) and fasting (8 steers; BW = 237 ± 17 kg) and using the WR model (8 steers; BW = 322 ± 30 kg). Steers were maintained in a controlled temperature (21°C) environment and treated as follows: 10 d diet adaptation, 1 d measurement of respiratory gases at 1.5 × NEm (Fed state; all steers d 11), 1 d measurement of respiratory gases under fasting conditions (Fasted; 8 steers d 12) or using the WR technique (8 steers d 12), and 7 d to monitor the reestablishment of intake. Steers were offered alfalfa cubes top-dressed with a mineral premix at 1.5 × NEm. Using an indwelling probe, core temperature (CT) and heart rate (HR) were monitored continuously during the days respiratory gases were measured. For fasting measurements using the WR technique, the reticulorumen was washed and refilled with ruminal buffer (NaCl = 96, NaHCO 3 = 24, KHCO 3 = 30, K 2 HPO 4 = 2, CaCl 2 = 1.5, and MgCl 2 = 1.5 mmol/kg of buffer) with Cr-EDTA aerated with 75% N 2 and 25% CO 2 before introduction to the rumen. Mean hourly CT, RQ, and daily HP between Fasted steers and WR steers were decreased for the WR steers on average from 8 to 24 h after removal of rumen contents (P = 0.049, P < 0.001, and P = 0.076, respectively). Fitting RQ data obtained during fasting to a 1-phase decay equation showed that plateau was achieved at 0.756 ± 0.003 and 0.719 ± 0.003 and time to plateau was 9 and 8 h for Fasted and WR steers, respectively. Mean RQ after WR were 0.778, 0.732, and 0.726 (SEM = 0.003) for time segments 0 to 8 h, 9 to 16 h, and 17 to 24 h, respectively. Mean fasting HP after WR was 18.8, 16.8, and 16.5 (SEM = 0.51) kJ/(h•kg 0.75 ) for time segments 0 to 8 h, 9 to 16 h, and 17 to 24 h, respectively. There were no significant differences in RQ and fasting HP (P = 0.23 and P = 0.81, respectively) between the time segment of 9 to 16 h and 17 to 24 h after rumen washing. In contrast, both RQ and HP differed (P = 0.090 and P = 0.081, respectively) across these same time segments for the Fasted group. Therefore, an accurate measurement of fasting HP can be obtained using a shorter-term measurement with the WR technique. This approach provides an alternative to the traditional 48 h fasting time or measurements made during the third and fourth day after starvation.

This study was designed to examine the influence of ractopamine (RAC) on whole-body and splanchnic energy balance. Six growing Holstein steers [body weight (BW) = 402 ± 39.5 kg] surgically fitted with an arterial and portal, hepatic, and mesenteric venous indwelling catheters were used in a repeated measures study. Treatments were a basal diet of alfalfa cubes fed at approximately 1.5&times maintenance energy requirements (days 1-21) and basal plus RAC (430 mg head d-1; days 22-42). On day 14 of each period, splanchnic and portal-drained viscera (PDV) energy balances were determined as the product of arterio-venous O2 difference and blood flow. Blood flow was determined using down-stream dilution of p-aminohippuric acid. Whole-body energy balance was determined on days 15-21 of each period, which included 7 d total excreta collection and 3 d of respiratory gas exchange measurements. Body weight and DM intake were greater (P 

The objective was to evaluate the effects of Alltech® Advantage Confinamento (a proprietary blend of trace minerals and yeast) on performance and carcass traits of Nellore cattle finished with high-intake supplementation during the dry season. Fifty-two Nellore bulls [526 ± 5.71 kg of body weight (BW); age of 28 mo old] were distributed in a randomized block design (block = BW). Four animals were slaughtered at the beginning of the experiment to estimate the initial hot carcass weight (HCW). The remaining animals were divided into two treatments: ad libitum supplementation (estimated daily intake = 20 g/kg BW; crude protein = 14%; total digestible nutrients = 74%) with sodium monensin or Advantage Confinamento (29.9 mg or 3 g/kg of dry matter of supplement, respectively). The animals were evaluated for 112 days (28 days of adaptation and three periods of 28 days; June to October, 2018). The experimental area was divided into 12 paddocks (one ha each; Brachiaria brizantha cv. Marandu...

Effects of a blend of live yeast and organic minerals as an alternative to monensin and inorganic trace minerals for beef cattle finished on pasture with high concentrate supplementation, on growth performance, intake, digestibility, liver trace mineral and carcass characteristics were evaluated. Forty-eight Nellore bulls were blocked by initial body weight and randomly assigned to one of the two experimental diets. The animals were raised in an experimental pasture divided into 12 paddocks equipped with an electronic system for monitoring individual feeding behavior and feed intake. Treatments were: (1) Monensin (MON), 30 mg/kg supplement dry matter of sodium monensin and trace minerals supplementation from inorganic sources; (2) AdvantageTM (ADV), 1.6 g/kg supplement DM of a blend of live yeast (Saccharomyces cerevisiae strains) and organic trace minerals. The use of ADV instead of MON led to greater supplement intake and greater intake of dietary components. Bulls fed ADV also ha...

This study aimed to evaluate the effects of increasing dietary levels of microalgae (ALG), rich in docosahexaenoic acid (DHA; All-G-Rich, Alltech, Nicholasville, KY), in isolipidic diets, on animal performance, nutrient digestibility, ruminal fermentation, milk fatty acid profile, energy balance, microbial protein synthesis, and blood serum metabolites in mid-lactating dairy cows. Twenty-four Holstein cows [130.3 ± 15.4 d in milk, and 30.8 ± 0.543 kg/d of milk yield (mean ± standard error)] were used in a 4 × 4 Latin square design experiment to evaluate the following treatments: control diet, without addition of ALG; and increasing levels of ALG [2, 4, and 6 g/kg of dry matter (DM)]. The ALG decreased DM intake and increased total-tract DM apparent digestibility. A tendency was observed for a quadratic effect on total-tract NDF digestibility by ALG inclusion, with peak value of the quadratic response at 4.13 g/kg of DM dose. Moreover, ALG increased ruminal pH and decreased acetate and total volatile fatty acid concentrations. Fat-corrected milk and energy-corrected milk were quadratically affected, and a tendency for a milk yield effect was observed when ALG levels increased, whereas maximal yields were observed with intermediate doses. Milk fat, protein, and lactose concentrations were diminished, whereas productive efficiency was improved by the increase of ALG levels. Saturated fatty acid proportions were decreased, whereas polyunsaturated fatty acid proportions were increased when ALG was fed. There was low DHA transfer into milk; however, ALG inclusion decreased C18:0, C18:1 cis-9, C18:2 cis-9,12, and C18:3 cis-9,12,15 proportions, and increased C18:2 cis-9,trans-11, C18:1 trans-9, and C18:1 trans-11 proportions. Gross energy intake was decreased, whereas no effect was observed on digestible, metabolizable, or net energy intake. The ALG inclusion quadratically affected the microbial protein synthesis, with maximal enhancement at 3.24 g/kg of DM dose, and also increased serum cholesterol concentration. Under the conditions of this experiment, the inclusion of ALG in diets for mid-lactating dairy cows decreased feed intake and increased nutrient digestibility, improving productive efficiency and modifying milk fatty acid profile. Estimated intermediate doses (1.22 to 2.90 g/ kg of DM) of DHA-rich ALG may be beneficial to milk, fat-corrected milk, and energy-corrected milk yields, and is recommended for dairy cows.

An experiment was conducted to evaluate the effects of inorganic trace minerals (TM) and reduced levels of TM by using proteinate forms of Co, Zn, Mn, and Cu, and Se-yeast in diets of transition cows on performance, TM concentrations in colostrum, plasma, and liver, blood metabolites, antioxidant status, peripheral neutrophil activity, and oocyte quality. Thirty-two Holstein cows (22 multiparous and 10 primiparous cows) were enrolled in this study from 30 d before the expected calving date to 56 DIM. Cows were blocked according to body condition score, parity, and previous milk yield and randomly assigned to one of the following treatments: control (CON), with TM (Zn, Cu, Mn, and Co) supplied in form of sulfate and Se as sodium selenite to meet or exceed requirement estimates of the National Research Council; and proteinate trace minerals (PTM), with TM supplied bound with AA and peptides at 50% of CON levels and inorganic Se replaced with Se-yeast at 100% of CON level. Treatments were supplied until 56 DIM. Eight cows were removed from the study because of early calving (n = 3) or health issues (n = 5); thus, data of 24 cows (16 multiparous and 8 primiparous cows) were used in the statistical analysis. No differences between treatments were detected on nutrient intake or digestibility. Total excretion of purine derivatives was decreased when feeding PTM during the prepartum period. Feeding reduced levels of TM in proteinate form resulted in greater yield of milk (27.7 and 30.9 kg/d for CON and PTM, respectively) and protein (0.890 and 0.976 kg/d) between wk 5 and 8 of lactation. No treatment differences were detected for feed efficiency, milk somatic cell count, and milk urea nitrogen. Cows fed PTM had lower milk fat concentration during the 56 d of evaluation (4.08 and 3.74% for CON and PTM, respectively). Selenium concentration was greater in colostrum of cows fed PTM compared with CON (48.5 and 71.3 µg/L for CON and PTM, respectively), whereas Zn, Cu, and Mn concentrations were not different. Cows fed PTM showed lower liver Cu concentration compared with CON (51.4 and 73.8, respectively). Plasma concentrations of Mn and Zn were lower, but plasma Se concentration tended to be higher with PTM treatment. Feeding PTM resulted in greater blood concentrations of urea-N (16.6 and 18.2 mg/dL for CON and PTM, respectively) and β-hydroxybutyrate (0.739 and 0.940 mmol/L). Counts of lymphocytes were higher with PTM but counts of monocytes were lower in complete blood cell count. No differences were observed in serum concentrations of superoxide dismutase and glutathione peroxidase. No differences were detected in phagocytosis and oxidative burst potential of neutrophils after incubation with bacteria. Cows fed PTM had fewer viable oocytes per ovum pickup in comparison with CON (8.00 and 11.6). Feeding PTM to transition cows may sustain performance without altering neutrophil activity despite some alterations in blood TM concentrations. More studies should be performed to evaluate production and fertility measurements when reducing TM dietary levels by using proteinate forms and Se-yeast with larger number of animals.

The objective of this study was to describe the differences
in freestall cleanliness and stall temperature
between a barn with Dual Chamber Cow Waterbeds
(DCCW; Advanced Comfort Technology, Reedsburg,
WI) and a barn with rubber-filled mattresses at the
University of Kentucky Coldstream Dairy Research
Farm from January 18, 2012, to May 3, 2013. Stall
cleanliness was measured twice weekly (n = 134) by
the same 2 observers using a 0.91 m × 0.91 m wire
grid containing 128 equally sized rectangles (10.16
cm × 5.08 cm). This grid was centered at the rear
portion of the stall; a rectangle that was visibly wet
or had any amount of feces present was defined as a
dirty rectangle. Weekly stall temperature (n = 66) was
measured by the same observer during a.m. milkings in
the same predetermined stalls. Feces and wet sawdust
were removed from the stalls before stall temperatures
were acquired. Temperatures were obtained using a
handheld thermometer at 30.48 cm above the stall
base as determined via dual laser measurements. Stall
temperature was measured on the front, middle, and
back of the stall first with clean sawdust and then with
the sawdust removed from the stall and wiped clean
with a towel. Daily temperature-humidity index (THI)
was calculated using Kentucky climate data calculated
through the University of Kentucky College of Agriculture
via a Campbell Scientific Inc. 23× data logger,
located 5.63 km from the Coldstream Dairy Farm. Stall
cleanliness was not different between the DCCW barn
(26.09 ± 0.89 rectangles) and the rubber-filled mattress
barn (23.70 ± 0.89 rectangles). Mean THI throughout
the study was 64.39 ± 0.82. Stall temperature was different
among THI categories. Temperature-humidity
index categories 1 (coldest), 2, 3, and 4 (warmest) had
THI ranges of 22.94 to 50.77, 50.77 to 64.88, 64.88 to
78.75, and 78.75 to 101.59, respectively. Stall temperatures
(°C; least squares means ± SE) were 2.26 ± 0.30,
8.86 ± 0.30, 15.52 ± 0.30, and 20.95 ± 0.30 for THI
categories 1 to 4, respectively. Stalls with rubber-filled
mattresses had a lower temperature (°C) than DCCW
with least squares means ± SE of 10.52 ± 0.21°C and
13.29 ± 0.21°C, respectively. The DCCW were probably
significantly warmer because water holds heat
well. The DCCW may have more of a heat-insulating
effect compared with rubber-filled mattresses.
Key words: waterbed , freestall , stall temperature

The objective of this study was to describe the differences in freestall cleanliness and stall temperature between a barn with Dual Chamber Cow Waterbeds (DCCW; Advanced Comfort Technology, Reedsburg, WI) and a barn with rubber-filled mattresses at the University of Kentucky Coldstream Dairy Research Farm from January 18, 2012, to May 3, 2013. Stall cleanliness was measured twice weekly (n = 134) by the same 2 observers using a 0.91 m × 0.91 m wire grid containing 128 equally sized rectangles (10.16 cm × 5.08 cm). This grid was centered at the rear portion of the stall; a rectangle that was visibly wet or had any amount of feces present was defined as a dirty rectangle. Weekly stall temperature (n = 66) was measured by the same observer during a.m. milkings in the same predetermined stalls. Feces and wet sawdust were removed from the stalls before stall temperatures were acquired. Temperatures were obtained using a handheld thermometer at 30.48 cm above the stall base as determined via dual laser measurements. Stall temperature was measured on the front, middle, and back of the stall first with clean sawdust and then with the sawdust removed from the stall and wiped clean with a towel. Daily temperature-humidity index (THI) was calculated using Kentucky climate data calculated through the University of Kentucky College of Agriculture via a data logger, located 5.63 km from the Coldstream Dairy Farm. Stall cleanliness was not different between the DCCW barn (26.09 ± 0.89 rectangles) and the rubber-filled mattress barn (23.70 ± 0.89 rectangles). Mean THI throughout the study was 64.39 ± 0.82. Stall temperature was different among THI categories. Temperature-humidity index categories 1 (coldest), 2, 3, and 4 (warmest) had THI ranges of 22.

Body condition scoring, an indirect measure of the level of subcutaneous fat in dairy cattle, has been widely adopted for research and field assessment or for management purposes on farms. The feasibility of utilizing digital images to determine body condition score (BCS) was assessed for lactating dairy cows at the Scottish Agricultural College Crichton Royal Farm. Two measures of BCS were obtained by using the primary systems utilized in the United Kingdom (UK-BCS) and the United States (USBCS). Means were 2.12 (±0.35) and 2.89 (±0.40), modes were 2.25 and 2.75, and ranges were 1.0 to 3.5 and 1.5 to 4.5 for the UKBCS (n = 2,346) and USBCS (n = 2,571), respectively. Up to 23 anatomical points were manually identified on images captured automatically as cows passed through a weigh station. Points around the hooks were easier to identify on images than points around pins and the tailhead. All identifiable points were used to define and formulate measures describing the cow's contour. For both BCS systems, hook angle, posterior hook angle, and tailhead depression were significant predictors of BCS. When the full data set testing only the angles around the hooks was used, 100% of predicted BCS were within 0.50 points of actual USBCS and 92.79% were within 0.25 points; and 99.87% of predicted BCS were within 0.50 points of actual UKBCS and 89.95% were within 0.25 points. In a reduced data set considering only observations in which the tailhead depression angle was available, adding the tailhead depression to models did not improve model predictions. The relationships of the calculated angles with USBCS were stronger than those with UKBCS. This research demonstrates the potential for using digital images for assessing BCS. Future efforts should explore ways to automate this process by using a larger number of animals to predict scores accurately for cows across all levels of body condition.

The Phase IV Cattle Temperature Monitoring System (CTMS; Phase IV Engineering Inc., Boulder, CO) marketed by MaGiiX (MaGiiX Inc., Post Falls, ID) uses a passive bolus equipped with a temperature sensor, a panel reader placed at a parlor entrance or exit to query the bolus, and a software package to collect, analyze, and view data. The biologically inert bolus resides in the cow's reticulum and is queried each time the cow passes the reader. Reticular temperature (RETT) and rectal temperature (RECT) were recorded simultaneously in the milking parlor exit lane in 4 consecutive milkings in each of 4 seasons, totaling 16 measurements per cow. The RETT were obtained by using the phase IV CTMS, whereas the RECT were obtained manually with a GLA M750 thermometer (GLA Agricultural Electronics, San Luis Obispo, CA). Data were edited to remove RETT likely to have been affected by a recent drinking bout. For the 2,042 observations used in analyses, means (±SD) were 39.28 (±0.41), 38.83 (±0.36), and 0.45 (±0.33) for RETT, RECT, and the difference between RETT and RECT, respectively. The RETT and RECT were strongly correlated (r = 0.645). The relationship between RETT and RECT varied by season, milking, housing system, and parity. Because dairy producers and veterinarians are accustomed to viewing rectal temperatures, equations to adjust reticular temperatures to a rectal-based scale may increase the utility of the phase IV CTMS. The resulting conversion equations were RECT = 19.23 + 0.496(RETT) for the a.m. milking and RECT = 15.88 + 0.587(RETT) for the p.m. milking.

Automatic temperature recording may allow early detection of disease, estrus, heat stress, and the onset of calving. The phase IV Cattle Temperature Monitoring System (MaGiiX Inc., Post Falls, ID) utilizes a passive bolus equipped with a temperature sensor, a stationary panel reader to query the bolus, and software to collect, analyze, and display data. One potential limitation to collection of reticular temperatures is the effect of water temperature and consumption on recorded temperatures. Two replicated 3 × 3 Latin square experiments were conducted at the Purdue Dairy Research and Education Center to assess the impact of water intake on reticular temperatures using the Cattle Temperature Monitoring System. Nine high-producing, mid-lactation, second-parity cows with low somatic cell counts were selected. Before administering a water treatment, access to feed and water was restricted for at least 2 h. Baseline reticular temperatures were established from measurements before water intake. In experiment 1, treatments were 25.2 kg of hot water (34.3°C ± 1.0), warm water (18.2°C ± 0.4), or cold water (7.6°C ± 0.4). In experiment 2, treatments were 18.9 kg of body-temperature water (38.9°C ± 0.2), cold water (5.1°C ± 0.4), or control (no water). Following water intake, reticular temperatures were collected for 3 h. In experiment 1, an initial dramatic decrease in reticular temperature was observed followed by a gradual increase toward baseline. Least squares means for maximum drop in temperature were 8.5 ± 0.5, 6.9 ± 0.5, and 2.2 ± 0.5°C for cold, warm, and hot water treatments, respectively. Yet at 3 h, reticular temperatures did not return to the baseline. In experiment 2, control cows remained within the baseline confidence interval through the observation period, and cows receiving body temperature water experienced an initial decrease in temperature (0.4 ± 0.2°C) with a return to within the baseline confidence interval within 15 min. Cows receiving cold water did not return to within the baseline confidence interval after a large decrease of 9.2 ± 0.2°C during the 3-h observational period. Moreover, a regression analysis of continued ascent in temperatures predicted that temperatures would return to baseline within 3.5 h. These results demonstrate that, when cows consume large quantities of cold water, the effect of water intake is sizable and sustained. The value of reticular temperatures for daily monitoring in a production setting hinges largely on the implications of this impact.

The objective of this study was to examine changes in teat-end hyperkeratosis (HK) in a herd transitioning from a standard pulsation milking system to an individual quarter pulsation milking system. The Milpro P4C (Milkline, Gariga di Podenzano, Italy) system stops milking individual quarters using an individual quarter pulsation milking system with 4 independent pulsation channels per cluster instead of 2. Teat-end HK was evaluated immediately after cluster removal using a scoring system where N signifies no ring; S signifies a smooth, raised ring; R signifies a rough ring; and VR signifies a very rough ring. Scorings were classified for 69 cows (48 Holstein, 12 crossbred, and 9 Jersey) on 5 dates relative

Wisconsin dairy producers who modernized their operations between 1994 and 1998 had positive feelings about their expansion experiences, accompanied by increased production and improved profitability and quality of life. The average herd in this survey experienced increased production during the 5-yr period studied. Nearly all producers were satisfied with their expansion experience. The negative effect on milk production normally associated with expansion was minimal for most years and did not exist if all herds were summarized together. Managing labor appeared to be the most daunting challenge facing producers following expansion.

A primary objective of the Wisconsin Dairy Modernization Survey was to compare features of free-stall barns available to dairy producers. This study used data from a large random sample of expanding dairy farms to determine whether the theoretical benefits of particular free-stall configurations bear out under on-farm conditions. Comparisons were made among herds using free-stall barns as their primary housing for new versus remodeled facilities, barn design, bedding used, feed-delivery design, manure removal strategies, animal restraint, maternity areas, overcrowding, and cooling methods. Producers who made the transition from tie-stall housing to free-stall housing were satisfied with this decision. New free-stall barns provided a more desirable environment for the herds than remodeled free-stall barns, although initial investments were higher. When new free-stall barns were compared, herds with four-row barns had higher production, lower somatic cell count, and higher stocking ra...