Browsing by Author "Schramm, Hollie H."

Now showing 1 - 5 of 5
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    Changes in Activity and Milk Components Around the Onset of Peripartum Diseases in Dairy Cows
    Griffith, Abigail Susanne (Virginia Tech, 2014-08-23)
    Activity and milk components were examined around disease onset in the periparturient period. Cows were monitored for daily rest bouts, rest duration, rest time, and step activity from -21 to +30 d relative to calving. Lactose concentration, fat to protein ratio (F:P), and milk yield were monitored. Diseases analyzed were assisted calving, mastitis, subclinical ketosis (SK), and a multiple disease category (MULTI) for animals who experienced more than one disease. Rest bouts decreased (d 0), step activity increased (d 0), and rest duration decreased (d -1) in animals that experienced assisted calving compared to controls. Mastitic cows showed fewer rest bouts (d -4, -3, -2, -1, and 0), increased activity (d -4, -2, and -1), decreased rest time (d -6, -5, -4, and -2), and decreased milk yield (d -4, -2, -1, 0) compared to controls. Cows with SK showed increased activity (d -5, -4, -3, and -2), decreased rest duration (d -7, -6, -5, -4, and -3), rest time (d -7, -6, -5, -4, -3, and -2), milk yield (d -4, -3, -2, -1, and 0) and lactose concentration (d -3, -2, -1, and 0) compared to controls. Animals categorized as MULTI showed increased activity (d -6, -5, -4, -3, and -2), increased F:P (d -2, -1 and 0), decreased rest time (d -5, -4, -3, and -2), and decreased lactose concentration (d -6, -5, -4, -5, -3, -2, -1, and 0) compared to controls. Deviations in activity and milk components could be used to proactively manage herd health.
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    Developing methods to improve welfare in periparturient dairy cows and pre-weaned calves
    Swartz, Turner Harrison (Virginia Tech, 2018-06-06)
    Animal behavior can be used to detect disease and well-being in dairy cattle. In this dissertation, we evaluated the accuracy of an accelerometer to measure step activity, lying time, and lying bouts in pre-weaned dairy calves. The output from the accelerometer was correlated with behavioral measurements taken from video footage. The accelerometer proved to be accurate in identifying step activity (r = 0.99), lying time (r = 0.99), and lying bouts (r = 0.99). The accelerometer was then used to detect behavioral changes occurring around respiratory disease events in pre-weaned calves. Activity declined 1 d prior to clinical disease onset, and this decline persisted for 3 d post-diagnosis. Furthermore, lying bouts declined beginning 2 d prior to diagnosis, and this effect persisted after diagnosis as well. However, aside from a slight reduction in milk intake, feeding behavior was not different between diseased and healthy calves. These data suggest that activity and lying behaviors may be a better measure than feeding behaviors for detection of respiratory disease in pre-weaned dairy calves. Dystocia has detrimental effects on both periparturient dairy cows and newborn calves. We administered a non-steroidal anti-inflammatory drug, meloxicam to periparturient dairy cattle. Treatments included administration prior to calving (MEL-PRE, n = 60), post-calving (MEL-POST, n = 69), or a negative control (CTL, n = 65). We measured the length of labor to determine which cows had easy or difficult calvings. Eutocic MEL-PRE animals produced 6.8 kg/d more milk than eutocic CTL. Regardless of calving difficulty, MEL-PRE animals produced more milk fat, protein, and lactose (kg/d) than the CTL. Additional research is needed to determine appropriate treatments for dystocic calvings. Calves born during the above trial were monitored to determine if meloxicam administration prior to calving impacted newborn calf health and behavior. Calves born difficultly displayed fewer lying bouts for the first few days after birth when compared to calves born easily. No effect of treatment or calving difficulty was noted on calf health. Additional research examining intervention strategies aimed at improving well-being of calves born difficultly is needed.
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    Ruminal volatile fatty acid absorption is affected by elevated ambient temperature
    Bedford, Andrea; Beckett, Linda; Harthan, Laura; Wang, Chong; Jiang, Ning; Schramm, Hollie H.; Guan, Leluo; Daniels, Kristy M.; Hanigan, Mark D.; White, Robin R. (2020-08-04)
    The objective of this study was to investigate the effect of short-term elevated ambient temperature on ruminal volatile fatty acid (VFA) dynamics and rumen epithelium gene expression associated with the transport and metabolism of VFA. Eight ruminally cannulated Holstein heifers (200 kg) were used in a factorial, repeated measures experiment with two treatments and two periods. During the first period, animals were provided with feed ad libitum and housed at 20 degrees C. During the second period, one group (HS) was housed at 30 degrees C and fed ad libitum. The other group (PF) was housed at 20 degrees C and pair-fed to match the intake of the HS group. During each period, animals were kept on treatment for 10 day, with sample collection on the final day. In the second period, indicators of heat stress were significantly different between PF and HS animals (P<0.05). There was a thermal environment effect on butyrate production (P<0.01) that was not associated with feed intake (P=0.43). Butyrate absorption decreased in HS animals (P<0.05) but increased in PF animals (P<0.05) from period 1 to period 2. There was a feed intake effect on BHD1 expression (P=0.04) and a tendency for a thermal environment effect (P=0.08), with expression increasing in both cases. Expression of MCT4 was affected by feed intake (P=0.003) as were all NHE genes (NHE1, NHE2, and NHE3; P<0.05). These results indicate that with low feed intake and heat stress, there are shifts in rumen VFA dynamics and in the capacity of the rumen epithelium to absorb and transport VFA.
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    Short Communication: Association between neonatal calf diarrhea and lying behaviors
    Swartz, Turner H.; Schramm, Hollie H.; Petersson-Wolfe, Christina S. (Elsevier, 2020-06-01)
    The objective of this study was to determine the association of neonatal calf diarrhea (NCD) with step activity and lying behaviors in pre-weaned dairy calves. Calves were housed in individual hutches for the first 6 days of life, and then moved into a group pen. On the day of birth, calves (n = 30) were fitted with an accelerometer, and step activity and lying behaviors were recorded. Calves were assigned a fecal score (FS) twice daily using a 0 to 3 scale, and were diagnosed with NCD (n = 10) when the score was a 3. To ensure the only association noted was due to NCD, calves that had any other health complications were excluded from analyses (n = 1). Calves with NCD were pair matched by age, breed, and birthdate to a healthy calf. Day 0 was designated as the date of NCD diagnosis. Calves with NCD spent less time lying (P < 0.05) and displayed more lying bouts (P < 0.05) of a shorter duration (P < 0.01) than healthy calves. Specifically, calves with NCD displayed more lying bouts on days -7 (P < 0.05), -6 (P < 0.01), -5 (P < 0.01), -4 (P < 0.01), and -3 (P < 0.05). Similarly, lying bout duration was shorter for calves with NCD on days -6 (P < 0.05), -5 (P < 0.05), -4 (P < 0.01), and -3 (P < 0.01). Additional research is needed to examine if these tools can be used to identify diseased calves prospectively.
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    Use of polyhalite mineral as an acidogenic product in the diets of close-up non-lactating dairy cows
    Richardson, Emily Sue (Virginia Tech, 2020-06-12)
    Polyhalite is a natural mineral that could be fed as an acidogenic product to induce a metabolic acidosis and prevent clinical hypocalcemia in dairy cows after calving. The overall objective of this study was to determine if the use of polyhalite mineral in the diets of pre-partum non-lactating dairy cows was effective as an acidogenic product. We measured the urine pH, dry matter intake, milk yield, and calcium and magnesium concentration of urine and serum in pre-partum and non-lactating dairy cows consuming diets containing a low dose of polyhalite (200 g/cow/day), a high dose of polyhalite (400 g/cow/day), calcium chloride (250 g/cow/day), or no acidogenic product. We hypothesized that including polyhalite mineral as an acidogenic product in the diets of pre-partum and non-lactating dairy cows will reduce urine pH and stimulate calcium metabolism mechanisms. We found that polyhalite effectively reduced urine pH and did not affect dry matter intake, and the stimulation of calcium metabolism was observed through an increase of calcium output in urine. In conclusion, feeding polyhalite mineral is an effective means for inducing metabolic acidosis without reducing dry matter intake. Based on these results, polyhalite should be fed at a dose of 400 g or more per cow per day to reduce urine pH.