Drinking Regime Evaluation of Boluses

Drinking Regime Evaluation of Boluses Ondrej Hanu; Daniel Bro, Milan Ã…  imko, Branislav Glik, Miroslav Jurek, Michal Rolinec, Robert Herke Slovak University of Agriculture in Nitra, Slovak Republic Original Paper Drinking regime evaluation with continuous ruminal monitoring boluses The aim of this study was to continuously monitored drinking regime of 7 dairy cows of Holstein breed using boluses during 24 weeks of lactation in relation to the outside temperature and observed daily drinking regime with the impact of drinking on rumen temperature at University Experimental Farm in Oponice. Animals were fed once daily and milked 3 times per day. The bolus pH and temperature values implemented via esophagus were measured every 15 minutes (96 data points per day) with accuracy  ±0.1 ph and  °C. Outside temperature by FREEMETEO meteorological server (48 times per day) was measured. Outside temperature can affect the drinking regime of dairy cows. During lactation weeks with higher outside temperature higher average number of drinking events (ANDE) was determined. The biggest difference between weeks in ANDE 18.33% (p=0.000) was found. Daily ANDE 9.25 ±1.85 and average daily temperature (ADT) 19.03 ±5.19  °C were observed. The most of the drinking events (ND E) concentrated to 4 main peaks (25.17%) during working hours (74.98%) was found. After the feed intake and milking the highest frequencies of NDE were observed. The highest average ruminal temperature after drinking (ARTAD) during night before first feeding due to lower NDE in this time were found. Overall ARTAD 36.86  °C was observed. The most measured ruminal temperatures after drinking (RTAD) (51.53%) in the interval 35 37  °C were found. This research proved that continuous ruminal monitoring with boluses is an appropriate tool for drinking regime evaluation and heat stress determination in herd of dairy cows. Keywords: bolus, rumen, temperature, water intake, outside temperature Water supplies for both humans and livestock are becoming a subject of increasing importance. Indeed, climate change and drinking water deficits in certain areas have meant that supplies of clean water for livestock are becoming problematic, at least during certain periods of the year. Water is considered the most important nutrient for health and performance in dairy herds. Loss of water from the body occurs through milk production, urine and fecal excretion, sweat and vapour loss from lungs (NRC, 2001). A adequate water intake is essential to avoid negative effects on animal health, performance and welfare (Murphy,1992; Meyer et al., 2004), and 25 and 50% restriction of drinking water relative to ad libitum intake decreased feed intake and milk yield in dairy cows (Steiger Burgos et al., 2001). Results of several experiments showed that an average of 83% of the water demand is met by drinking (NRC, 2001). Many studies found the association between water intake and outside temperatu re and between water intake and the number of drinking events (Matarazzo et al., 2003; Brown-Brandl et al., 2006; Arias et al., 2008). Drinking activity can be monitored continuously and simultaneously for randomly enrolled cows using a data acquisition system based on an individual radio frequency identification collar (Cardot et al., 2008) or with observers (Jago et al., 2005). Huzzey et al. (2005) monitored drinking activity of dairy cows using video cameras connected to a video multiplexer and a time-lapse videocassette recorder. Bewley et al. (2008) monitored ruminal temperature using boluses permanently residing in the cows reticulum and indentified temperatures influenced by drinking events. The aim of this study was to monitored drinking regime of dairy cows using boluses during lactation in relation to the outside temperature, daily drinking regime and the impact of drinking on rumen temperature. 2.1 Animals and housing Measured data from 7 dairy cows of Holstein breed (average age 3.57) in cooperation with the University Experimental Farm in Oponice during 24 lactation weeks were collected. Selected cows had average milk production 10 175 kg per lactation with 3.94% of fats, 3.10% of crude proteins and 4.70% of lactose. Experimental cows were housed in the groups with another dairy cows together. 2.2 Feeding and water availability Animals were fed once daily with Total Mix Ratio (Table 1) ad libitum between 4:00 and 5:00 and milked 3 times per day at 6:00, 12:00 and 18:00. Corn silage (pH 3.85) and alfalfa silage acidity (pH 4.85) with Sodium Bicarbonate (550 g.head-1) and Magnesium Oxide (51 g.head-1) were neutralised. In one section for 20 dairy cows two drinkers were available. Table 1 Total Mix Ratio composition DM (kg) NEL (MJ.kg-1) CP (%) NDF (%) Starch (%) 25.45 153.86 15.74 24.35 25.39 abbreviations: DM dry mater, NEL netto energy of lactation, CP crude protein, NDF neutral detergent fiber 2.3 Data measuring and data collecting Every dairy cow had implemented farm bolus for continual data measuring which was implemented through esophagus orally with the use of special balling gun. The bolus pH and temperature values were measured every 15 minutes (96 data points per day) with accuracy  ±0.1. Outside temperature by FREEMETEO meteorological server (48 times per day) was measured. Used boluses (eCow Devon, Ltd., Great Britain) are characteristic with its small dimensions (135 27 mm) and weight 207 g. Data with the handset with antenna and dongle connected with USB dongle connector with the radio frequency 434 MHz in the milking parlour were downloaded. Collected data were summarized with HathorHBClient v. 1.8.1. 2.4 Statistical evaluation Statistical evaluation with IBM SPSS v. 20.0 was realised. Descriptive statistics with One-way ANOVA were recalculated. Statistically differences between average daily outside temperatures (ADT), average ruminal temperatures after drinking (ARTAD) and average numbers of drinking events (ANDE) with post hoc Tukey Test were determined. Effect of outside temperature on number of drinking events with Pearson correlation coefficient (r) was realised. As drinking event a decrease in ruminal temperature less than -0.70% and ruminal pH less than 0.00% with previous data point using data filter was selected. Drinking regime of dairy cows during lactation with average temperatures during drinking events in the Figure 1 are shown. ANDE during monitored period 9.25 ±1.85 and ADT 19.03 ±5.19 were observed. Minimal reported ANDE found Jago et al. (2005) 5.2. Higher average ANDE for monitored period observed Huzzey et al. (2005) 9.5 ±0.4 and Perera et al. (1986) 9.4. Cardot et al. (2008) determined ANDE 7.3 ±2.8 during their experiment. The effect of ADT r=0.132 on ANDE was determined (p=0.001) but in 19 cases the same change both increase or decrase in the comparison with previous week between ANDE and ADT was found. Gonzà ¡lez Pereyra et al. (2010) found effect of outside temperature on ANDE r=0.507 (p