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1.
《Journal of dairy science》2019,102(8):7398-7407
The present study investigated the effect of straw yard housing during the dry period and 2 d of additional maternity pen housing postcalving on lying and feeding behavior and calving difficulty in Holstein dairy cows. In this study, 122 multiparous cows were moved to either a straw yard or into freestall housing 4 wk before their expected calving date. Cows that had been housed in straw yards stayed in the maternity pen for an additional 2 d after their calving day, but cows that had been housed in freestalls were moved to the general lactation group the morning after calving. Lying time, lying bouts, feeding time, number of feeder visits, feed intake, feeding rate, and assisted calvings were recorded. Observations were divided into 2 periods: precalving (the 4-wk dry period before calving) and postcalving (the day of calving and the 2 d after). During the precalving period, cows housed in straw yards showed a higher number of lying bouts but no difference in lying time compared with cows housed in freestalls. Cows that were housed longer in the straw-bedded maternity pen postcalving spent more time lying during the 2 d postcalving and had a higher number of lying bouts on the day of calving than cows moved to the freestall area on the day postcalving. Additionally, cows that were housed longer in the maternity pen had a slower feeding rate and longer total feeding time during the 2 d after calving than cows with a shorter stay in the maternity pen. We found no difference in the number of assisted calvings. This study suggests that straw yard housing during the dry period may facilitate the transition between standing and lying. Furthermore, the extended stay in the maternity pen postcalving increased lying time, the number of lying bouts, and feeding time, but decreased feeding rate compared with cows that were moved to the general lactation group on the day postcalving. These results suggest potential recovery benefits with an extended stay in a maternity pen postcalving. However, further studies are needed to separate the effects of housing in the dry period and the effects of an extended housing in individual maternity pens.  相似文献   

2.
Dairy cows that have a difficult calf delivery (dystocia) are more likely to develop health complications after calving, reducing productivity and welfare. Understanding the behavioral cues of dystocia may facilitate prompt obstetric assistance and reduce the long-term effect of the challenging delivery. The aim of this study was to describe the effects of dystocia on dairy cow behavior during the period around calving and to assess the use of these behaviors as potential indicators of dystocia. Individual dry matter intake, water intake, feeding and drinking time, meal size, standing time, and number of transitions from standing to lying positions (bouts) were recorded during the 48-h period before and after the time of calf delivery for 22 Holstein cows [11 cows with dystocia and 11 cows with unassisted delivery (eutocia)]. Cows with dystocia consumed 1.9 kg less during the 48 h before calving compared with cows with eutocia (14.3 ± 1.0 vs. 16.2 ± 1.0 kg, respectively), and this difference increased to 2.6 kg in the 24 h before calving (8.3 ± 0.7 vs. 10.9 ± 0.7 kg/d). There were no differences in drinking time between the groups, but cows with dystocia consumed less water 24 h before calving (22.4 ± 4.4 vs. 36.2 ± 4.4 kg/d, respectively) and consumed more water during the 24-h period after calving (56.9 ± 3.1 vs. 48.7 ± 3.1 kg/d) compared with cows with eutocia. Cows with dystocia transitioned from standing to lying positions more frequently than cows without dystocia beginning 24 h before calving (10.9 ± 0.7 vs. 8.3 ± 0.7 bouts/d). Dry matter intake and standing bouts in the 24 h before calving were the most accurate variables in discriminating between cows with and without dystocia, suggesting that cows with dystocia begin to alter their behavior beginning 24 h before calving.  相似文献   

3.
Claw horn lesions, including sole hemorrhages and sole ulcers, are a major cause of lameness in dairy cattle. These lesions often develop in the weeks around calving and become visible 8 to 12 wk later. The aim was to determine whether cows that are diagnosed with claw horn lesions several weeks after calving behave differently during the calving period when the lesions are thought to first develop. The claws of 26 multiparous Holstein dairy cows were scored for sole hemorrhage severity and presence of sole ulcers 2 wk before calving, 3 wk after calving, and every 4 wk thereafter until 15 wk after calving. Of the 26 cows, 13 cows had no or low lesion scores up to 15 wk and 13 cows had at least 1 new severe lesion or sole ulcer diagnosed between 7 and 15 wk after calving. Behavior (dry matter intake, feeding time and rate, number and size of meals, standing time, number and duration of standing bouts, location of standing, and displacements at the feed bunk) was recorded from 2 wk before calving to 3 wk after calving. Behavior during the 2 wk before calving, first 24 h after calving, 1 wk after calving, and 2 to 3 wk after calving was compared between cows with and without lesions in mid lactation. Multivariate regression was used to determine the predictive value of each behavior and combination of behaviors on lesion diagnosis. Cows diagnosed with lesions in mid lactation spent more time standing than cows without lesions during the 2 wk before (832 ± 29 vs. 711 ± 29 min/d) and 24 h after (935 ± 46 vs. 693 ± 46 min/d) calving. These differences were driven by an increase in the time spent perching with front feet in the stall (241 ± 22 vs. 147 ± 22 min/d at 2 wk before calving) and an increase in standing bout duration (101 ± 10 vs. 56 ± 10 min/bout at 24 h after calving). Compared with cows without lesions, cows with lesions consumed feed at a faster rate (86 ± 3 vs. 77 ± 3 g/min) during the 2 wk before calving and consumed more feed (17.9 ± 0.9 vs. 12.3 ± 0.9 kg/d) during the 24 h after calving. The number of displacements at the feeder was not different between groups. These results indicate that a combination of feeding and standing behavior during the transition can serve as early indicators of claw horn lesions in mid lactation.  相似文献   

4.
Transition dairy cows are vulnerable to the negative consequences of depressed feed intake around calving. Competition can decrease feeding activity in midlactation cows, but the effects of competition on the transition cow are not well understood. The objective was to test the effect of competition on the behavior and feed intake of transition cows. Standing behavior, feeding behavior, and dry matter intake were monitored from 1 wk before to 2 wk after calving for 36 Holstein dairy cows. Displacements at the feed bins were recorded the week before calving. Cows were assigned to either competitive (2:1 cows:feed bin) or noncompetitive (1:1 cow:feed bin) treatments. Treatment groups were balanced for parity and baseline feeding measures, resulting in 8 primiparous and 10 multiparous cows per treatment. Competition increased the number of displacements at the feed bins for both primiparous and multiparous cows. Primiparous cows had no change in feed intake or standing time when fed in a competitive environment, but did increase the time spent for each meal during the week before calving (28 ± 1.5 vs. 24 ± 1.5 min/meal). In the week before and after calving, competitively fed multiparous cows had a lower feeding time per visit than noncompetitively fed cows (4.2 ± 0.5 vs. 5.8 ± 0.5 kg/visit and 5.3 ± 0.7 vs. 7.0 ± 0.7 kg/visit, respectively). Multiparous cows ate at a faster rate 2 wk after calving (142 ± 11 vs. 105 ± 11 g/min). Multiparous cows in the competitive treatment increased the time they spent standing (without eating) during the week after calving compared with cows in the noncompetitive treatment (820 ± 44 vs. 649 ± 44 min/d). Feeding rate was correlated with a displacement index in multiparous cows, whereby cows with lower displacement indices ate more rapidly. Results indicate that restricting access to feed increases displacements regardless of parity, and alters the feeding and standing behavior of primiparous and multiparous cows differently.  相似文献   

5.
The present study investigated the flooring preference during the 30 h before parturition in Holstein dairy cows housed individually in a maternity pen. Seventeen multiparous cows were moved, on average, 2 d before expected calving date into an individual maternity pen with 3 different flooring surfaces: 10 cm of sand, pebble-top rubber mats, or concrete flooring, each covered with 15 cm of straw. Calving location, lying time, and total time and number of lying bouts on each of the floor types were recorded during 2 periods: precalving (24 to 29 h before calving) and at calving (0 to 5 h before calving). Ten cows calved on sand, 6 on concrete, and 1 on the rubber mat. Lying bouts increased during the hours closest to calving, regardless of flooring. The number of lying bouts did not differ between flooring types precalving but cows had more lying bouts on sand and concrete compared with rubber at calving. Cows spent more time lying down on sand and concrete compared with rubber precalving, but lying times did not differ between treatments at calving. Cows that calved on sand spent more time lying on sand at calving compared with the other 2 flooring types. Cows that calved on concrete did not show a flooring preference at calving. These results indicate that rubber mats are the least preferred by dairy cows in the maternity pens, even when covered with a deep layer of straw.  相似文献   

6.
《Journal of dairy science》2019,102(8):7371-7384
Lying behavior and activity may provide useful information for the prediction of an imminent calving and the health of transition dairy cows; however, it is important first to understand what constitutes typical lying behavior and activity because this has not been defined for grazing dairy cows during the transition period. Our objective was to describe changes in lying behavior and activity in grazing dairy cows during the transition period using varying phenotypes typical of commercial dairy herds under grazing systems. Behavior data from IceTag or IceQube (IceRobotics, Edinburgh, Scotland) triaxial accelerometers were collected for 310 cow parities from multiparous, mixed-age (mean ± standard deviation; 4.5 ± 1.65 yr), and mixed-breed [Holstein-Friesian (HF), n = 216; and HF × Jersey, n = 94] grazing dairy cows from 4 parent experiments. The IceTags or IceQubes captured lying and activity data during the transition period (−21 to 34 d relative to calving) to allow the calculation of daily lying time (h/d), daily lying bouts (LB; no./d), mean LB duration (min/bout), and the number of steps taken (steps/d). Lying behavior and activity were analyzed using a repeated measures ANOVA during 3 periods: PRE (−21 to −3 d), POST (3 to 21 d), and the day of calving (d 0). Lying time was lower on d 0 (7.25 h/d) compared with PRE and POST lying times (10.3 and 8.58 h/d, respectively), with more frequent LB on d 0 (12.9 no./d) compared with the PRE and POST daily LB (8.15 vs. 7.74 no./d). Cows took more steps POST (4,424 steps/d) compared with d 0 and PRE (4,105 and 2,289 steps/d, respectively). Regression analysis determined that daily lying time decreased substantially from −3 to 0 d (slope = −1.03 ± 0.07 h/d) and from −2 and −1 d for daily LB (slope = 5.09 ± 0.54 no./d), which may be due to the calving event itself but also reflect restlessness. Daily lying time, daily LB, LB duration, and number of steps taken were substantially altered at the time of the calving event in grazing dairy cows. Cows were more active, spent less time lying, and took more steps postcalving compared with precalving, and it appears that this behavior may largely be due to activity associated with twice daily milking. Mean lying behavior and activity measures were more highly variable across individuals than across groups. Information available via activity monitors may contribute to the improvement of individual management of transition dairy cows, and this research provides a benchmark for typical changes in behavior during the transition period in grazing systems.  相似文献   

7.
The purpose of this study was to evaluate the effect of rumination times and days spent in a close-up group before calving (DCU) on early-lactation health and reproductive outcomes in dairy cows. Data were gathered for 719 cows located in a single herd. Herd management and reproductive records were analyzed for cows receiving treatment in the first 30 d of lactation (days in milk; DIM) for clinical mastitis, reproductive tract disease, ketosis, milk fever, and displaced abomasum. Rumination times for each cow were downloaded daily from the herd's automated collar system used to generate heat and health alerts for each cow beginning at 21 d precalving until 14 d postcalving. During the first 30 DIM, 121 cows (18%) developed at least 1 disease—any combination of ketosis (40 cows, 5.9% of total), mastitis (17 cows, 2.5%), metritis (75 cows, 11%), milk fever (17 cows, 2.5%), or displaced abomasum (28 cows, 4.1%); 305 cows (45%) were pregnant again at 100 DIM, and an additional 139 cows (20%) were pregnant at 150 DIM. Principal component analysis was used to determine the relationship between gestation length and DCU and their association with the odds of developing disease in early lactation. We did not find any significant association between precalving rumination time and disease within the first 30 DIM. Higher rumination time in the week before calving was shown to be strongly linked to a shorter time to subsequent pregnancy, whereas rumination times postcalving were not associated with changes in the time to pregnancy. Principal component analysis showed that a curvilinear combination of gestation length and DCU (principal component 1) was significantly associated with changes in disease incidence in the first 30 DIM. Gestation length and time spent in close up are important management factors in reducing the incidence of disease in early lactation, and rumination times around calving may help predict future reproductive outcomes.  相似文献   

8.
The effects of gradual versus abrupt cessation of milking at dry-off in dairy cows are not well understood, but gradually reducing milk production in human mothers is known to reduce discomfort and milk leakage. This study compared the effects of abrupt versus gradual cessation of milking on milk leakage and dairy cow behavior. Holstein dairy cows were housed in groups of 6 and randomly assigned to either abrupt milk cessation (i.e., dry-off on d 0) or gradual milk cessation (i.e., skipped milkings beginning on d 0; dry-off on d 5). Four replicates were performed over time, for a total of 24 cows (mean ± SD; parity = 2.3 ± 1.2; milk production the day before d 0 = 24 ± 5 kg/d). Intramammary antibiotic, internal teat sealer, and external teat sealant were administered at dry-off. Measurements were taken from d −3 to 8 relative to dry-off. Three periods were identified for behavior data: baseline (d −3 to 1), period 1 (abrupt cows dry, gradual cows milking; d 0–4), and period 2 (all cows dry; d 5–8). Lying time was recorded with data loggers. Video scan samples (5-min intervals) were used to measure feeding time and motivation to be milked (i.e., standing at the pen's exit gate). Milk leakage was monitored every 20 min during the 2-h period following the milking times of 0500 and 1500 h after complete cessation of milking (period 1 for abrupt vs. period 2 for gradual). Composite milk samples were taken before dry-off (d −1, 0, and 5) and at the start of the next lactation (colostrum, 24 h and 7–10 d postcalving) to determine somatic cell score (SCS) and conduct bacteriological examinations in clinical mastitis cases. Regardless of treatment, dry-off resulted in reduced lying time [14.1 vs. 13.2 h/d; standard error of the difference (SED) = 0.2], reduced lying bouts (10.7 vs. 8.3 bouts/d; SED = 0.2), increased lying bout duration (1.4 vs. 1.7 h/bout; SED = 0.03) and increased feeding time (5.0 vs. 5.9 h/d; SED = 0.2). Compared with baseline, the odds of standing at the gate increased for abrupt cows (period 1: odds ratio = 6.2; 95% CI: 2.7–14.4; and period 2: odds ratio = 5.2; 95% CI: 1.8–14.6). No increase in time spent standing at the gate was noted in gradual cows. Frequency of leakage was greater in abrupt versus gradual cows (75 vs. 27%). Although the gradual treatment showed an increase in SCS over the 5 d of reduced milking frequency, both treatments showed an increase in SCS at calving and both returned to pre-experiment levels within 7 to 10 d after calving. This work demonstrates that gradually reducing milking frequency in high-producing cows results in reduced time spent anticipating milking and reduced milk leakage after dry-off.  相似文献   

9.
The objectives of this study were to describe the lying behavior of primiparous dairy cows under pasture-based systems during the pre- and postcalving period and characterize the association of lying behavior and analytes related to energy metabolism during this period with claw horn disruption lesion development later in lactation. Our convenience sample included 39 primiparous Holstein cows from 3 commercial farms that were assessed for body condition score (BCS; 5-point scale, 0.25-point increments) and had blood collected at wk ?3, ?2, ?1, 1, 2, and 3 relative to calving date. Blood samples were assayed for nonesterified fatty acids, β-hydroxybutyrate (BHB), and cholesterol concentrations. Electronic data loggers (HOBO Pendant G Acceleration, Onset Computer Corporation, Bourne, MA) recorded lying behavior at 1-min intervals from 3 wk before calving to 3 wk after calving. Starting at 4 wk after calving and until 16 wk after calving, cows were examined for claw lesions at approximately 4-wk intervals. Sole lesions and white line lesions were scored on a 0 to 10 scale. Of the 39 primiparous cows, 19 cows scored 0 at all exams during the entire study period and 20 cows had at least 1 severe lesion (score ≥4) between 8 and 16 wk after calving. Time spent lying before calving averaged 10.3 ± 0.3 h/d, but declined to 7.3 ± 0.3 h/d after calving (least squares means ± standard error). At calving, we noted an increase in the number of lying bouts (12.9 ± 0.45 bouts/d) compared with the pre- and postcalving averages of 11.6 (±0.53) and 9.1 (±0.47) bouts, respectively. Cows that developed claw lesions later in mid lactation spent less time lying down than cows without lesions during wk 3 after calving compared with healthy cows (7.29 ± 0.22 vs. 8.51 ± 0.16 h/d). Lesion cows had fewer lying bouts per day, and these bouts were of longer duration than no-lesion cows after calving. Increased odds of lesion were found to be associated with shorter lying times and fewer number of lying bouts during wk 3 (odds ratio = 1.23). Nonesterified fatty acids (747 ± 58 vs. 990 ± 86.85 µmol/L) and BHB (0.77 ± 0.06 vs. 0.60 ± 0.04 mmol/L) concentrations during wk 1 were greater in cows that developed claw lesions relative to cows that did not develop lesions. The BHB concentrations also remained higher in wk 2 for cows that developed claw lesions (0.63 ± 0.04 vs. 0.46 ± 0.03 mmol/L) compared with cows that did not develop any lesions. Cows that developed lesions experienced greater losses in BCS from wk ?3 to 3 than cows without lesions (0.74 ± 0.01 and 0.61 ± 0.01 BCS change, respectively). In summary, changes in lying behavior and energy metabolic status after calving were associated with claw horn disruption lesions in mid-lactation primiparous cows under pasture-based systems.  相似文献   

10.
The influence of a monensin controlled-release capsule, which was administered 3 wk before the calving date, on diet digestibility and nitrogen utilization was investigated in 16 multiparous dairy cows between approximately 10 and 3 d precalving and 3 and 9 d postcalving. Monensin decreased rumen ammonia from 5.4 to 3.2 mg dl(-1) precalving and from 6.0 to 4.9 mg dl(-1) postcalving. Blood urea concentrations were increased by monensin from 4.93 to 5.28 mM precalving and from 5.27 to 5.81 mM postcalving, but these increases were not statistically significant. Precalving, monensin increased the apparent digestibilities of neutral detergent fiber from 52.8 to 62.1%, of acid detergent fiber from 50.7 to 58.7%, and of gross energy from 60.5 to 66.7%. Postcalving, monensin increased the apparent nitrogen digestibility from 63.7 to 71.5%, which resulted in an improvement in the nitrogen balance from -77.8 to -44.9 g d(-1). The monensin controlled-release capsule contributed to increasing the availability of dietary nitrogen to the transition dairy cow during the critical postcalving period.  相似文献   

11.
The objective of this observational study was to examine the effect of lameness on the resting behavior of dairy cattle through the transition period in a mattress-bedded commercial freestall facility, and explore the relationships between lameness, behavior, and metabolic indicators of disease. A convenience sample was used, comprised of 40 multiparous and 17 primiparous Holstein cows that were recruited as they entered the close-up pen and tracked through the maternity, hospital, and fresh pens. At recruitment, 87.5% of multiparous cows and 23.5% of primiparous cows showed evidence of abnormal gait. Lying time decreased from 16 d before calving from a least squares means ± standard error of 13.5 ± 0.6 h/d to a nadir of 10.6 ± 0.38 h/d on the day of calving. After a period of increased rest after calving, lying time stabilized by d 6 to between 9.8 and 10.8 h/d. This change was accompanied by an increase in the number of lying bouts per day from least squares means (95% confidence limits) of 11.2 (10.0 to 12.4) bouts per day to a peak of 17.7 (16.5 to 18.8) bouts per day on the day before calving, and a decrease in the duration of each lying bout. Resting behavior was influenced by calving month, temperature humidity index, body condition, parity, and lameness. Moderate and severely lame cows had significantly longer lying times throughout the transition period before and after calving, but most notable was a dramatic increase in the number of lying bouts observed 3 d before and after calving. In the straw-bedded, loose-housed maternity pen, moderate and severely lame cows had 20.3 (19.1 to 21.5) bouts per day, compared with 15.6 (14.3 to 16.8) bouts per day for nonlame cows. We hypothesized that this alteration in behavior may be associated with hypersensitivity to pain due to lameness. A total of 26.3% of cows tested above a threshold of 1,400 μM β-hydroxybutyrate. Moderate and severely lame cows had a least squares means (95% confidence limits) β-hydroxybutyrate concentration of 1,165 (1,037 to 1,291) μM that was significantly greater than 697 (560 to 834) μM for slightly lame cows and 687 (551 to 824) μM for nonlame cows. In summary, lameness significantly altered the resting behavior of cows during the transition period and was associated with elevated risk for ketosis in the study herd.  相似文献   

12.
This study aimed to assess the effect of shelter provision during the prepartum period on lying, ruminating, and feeding behavior in outdoor-housed dairy cows exposed to winter weather conditions in a temperate climate. We also aimed to determine whether shelter provision during the prepartum period influenced blood analytes related to energy metabolism, body cleanliness, and health status. In this study, 2 cohorts of 12 multiparous Holstein prepartum cows were tested in winter. Twenty-five days before their expected calving date, the cows in each cohort were paired and randomly assigned to an open paddock without shelter or to one with access to an artificial shelter until calving. Shelter use, lying time, number of lying bouts, duration of lying bouts, rumination time, and feeding time were continuously recorded during the 3 wk before calving. Cows were assessed weekly for body cleanliness throughout the 3-wk prepartum period. A blood sample was taken from the coccygeal vein of each cow at wk ?3, ?2, ?1, 1, 2, and 3 relative to calving date, and were assayed for nonesterified fatty acids (NEFA), β-hydroxybutyrate, and haptoglobin concentrations. Cases of clinical health disorders after calving were also recorded. The cows spent 60% of their daily time in the shelters, and for 75% of that time they were lying down. Cows with access to shelter during the prepartum period lay down around 3.2 h/d more than cows without shelter on wk ?3 and ?2 relative to calving. The cows with shelter access spent less time feeding during the morning (wk ?3: 29.7 min; wk ?2: 12.1 min; wk ?1: 17.3 min) and afternoon (wk ?3: 18.2 min; wk ?2: 21.9 min) than cows without shelter access. As well, cows with shelter access showed a higher body cleanliness score (~92 vs. ~48%) and lower NEFA concentrations (wk ?2: 0.27 vs. 0.44 mmol/L; wk ?1: 0.46 vs. 0.64 mmol/L) in the precalving period, and lower haptoglobin concentrations in the first week postpartum (0.34 vs. 0.79 mg/mL) than cows without shelter access. We observed no treatment differences in daily rumination time, β-hydroxybutyrate concentrations, or postpartum health disorders. Despite the small number of dairy cows used in this study, these findings suggest that having access to a shelter during the prepartum period increases lying time, improves body cleanliness, and reduces adipose mobilization. Therefore, it is important to provide a protected area for the welfare of prepartum dairy cows exposed to winter climate conditions.  相似文献   

13.
Fifty-two multiparous dairy cows were allocated to 4 treatments consuming 5.4, 8.2, 10.0, or 11.0 kg/d of pasture dry matter per cow for 27 +/- 9.6 d precalving. This equated to 1.3, 1.9, 2.4, and 2.6% of body weight (BW; not including the conceptus weight). Following calving, all cows were fed ad libitum on pasture. Blood was sampled 17 d precalving, on day of calving, and on d 1, 2, 3, 4, 7, 14, 28, and 35 postcalving. Results suggest that the near-term grazing dairy cow requires 1.05 MJ of ME/kg of BW(0.75) and that previous estimates of energy requirements were underestimated. Precalving plasma concentrations of glucose, insulin-like growth factor-1, and leptin increased quadratically with increasing pasture intake. This was associated with precalving plasma concentrations of growth hormone that declined linearly, and concentrations of nonesterified fatty acids and beta-hydroxybutyrate that declined quadratically with increasing dry matter intake (DMI). Postcalving plasma concentrations of these metabolites showed no lasting effect of precalving feeding. The effect of precalving nutrition on milk production was small, and other than milk fat, was confined to wk 1 postcalving. Milk fat yield increased with increasing precalving DMI and calving body condition score until wk 3 post-calving, after which treatment effects were not evident. These results indicate that the level of feeding in grazing dairy cows during the last month before calving has only small effects on cow metabolic and hormonal status, and on milk production in the first 5 wk of lactation.  相似文献   

14.
In the transition from the pre- to postcalving state, the demands on the cow increase from support of gestation to high rates of milk production. This extra demand is met partly by increased intake but may also involve altered metabolism of major nutrients. Six multiparous Holstein cows were used to monitor changes in net fluxes of nutrients across the portal-drained viscera and liver (splanchnic tissues) between late gestation and early lactation. Blood samples were obtained simultaneously from the portal, hepatic, and subcutaneous abdominal veins and the caudal aorta 18 d before expected calving and 21 or 42 d after calving. On the day of blood sampling and the 3 d preceding sampling, cows were fed every 2 h. The precalving (1.63 Mcal of net energy for lactation/kg and 1,326 g of metabolizable protein/d) and postcalving (1.72 Mcal of net energy for lactation/kg and 2,136 g of metabolizable protein/d) diets were based on corn silage, alfalfa hay, and corn grain. Dry matter intake increased postcalving. Net splanchnic release of glucose increased postpartum because of tendencies for both increased portal absorption and net liver release. Increased removal of lactate, rather than AA, contributed to the additional hepatic gluconeogenesis. Although portal absorption of AA increased with intake at the onset of lactation, hepatic removal of total AA-N tended to decline. This clearly indicates that liver removal of AA is not linked to portal absorption. Furthermore, net liver removal relative to total liver inflow even decreased for Gly, His, Met, Phe, and Tyr. Together, these data indicate that in early lactation, metabolic priority is given to direct AA toward milk protein production rather than gluconeogenesis, in cows fed a corn-based ration.  相似文献   

15.
A prospective field study involving 251 Holstein cows and heifers from five dairy farms near Guelph, Ontario, Canada, was conducted to measure the effect of monensin delivered in a controlled release capsule 3 wk precalving on metabolic function in dairy cows immediately pre- and postcalving. At 3 wk before expected calving, cows were randomly assigned to receive either a controlled release capsule containing monensin or to serve as negative controls. Cows were blood sampled once per week precalving and once in the week following calving, at the same time of day and the same day of the week. Serum was evaluated for beta-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), cholesterol, urea, glucose, calcium, and phosphorus. Monensin-treated cows had significantly decreased NEFA and BHBA and significantly increased concentrations of serum cholesterol and urea in the week immediately precalving. No effect of treatment was observed for calcium, phosphorus, or glucose in the precalving period. After calving, concentrations of phosphorus were lower and BHBA tended to be lower, and cholesterol and urea were higher in monensin-treated cows. There was no effect of treatment on NEFA, glucose, or calcium in the first week postcalving. Monensin treatment administered precalving significantly improved indicators of energy balance in both the immediate precalving and postcalving periods. The findings indicate better energy metabolism in monensin-treated cows as they approach calving. Improvement of energy balance before calving is important for the prevention of energy associated metabolic diseases, such as retained placenta, clinical ketosis, and displaced abomasum, which might occur immediately postcalving.  相似文献   

16.
Hormonal signals differentially regulate the timing of parturition, as well lactogenesis and, potentially, colostrum formation in the mammary gland. Non-neuronal serotonin (5-HT) is a homeostatic regulator of the mammary gland. In the current study, we manipulated the timing of first milking to investigate its effects on serum 5-HT and calcium concentrations in the maternal and calf circulation, as well as in colostrum. Twenty-three cows were randomly assigned to a control (CON; n = 10) group, milked for the first time at 4 h postcalving, or a treatment (TRT; n = 13) group, milked for the first time approximately 1 d before calving in addition to 4 h postcalving. Maternal blood samples were collected for 4 d precalving, 3 times daily, and 1 blood sample was taken 4 h postcalving. Calf blood samples were collected 4 (before first colostrum feeding) and 12 h after birth, and at 3 wk of age. Calves from both treatments were fed colostrum from their respective mothers. Serum 5-HT concentrations were greater in CON cows and decreased significantly in TRT cows after milking was initiated precalving (951 vs. 524 ± 111 ng/mL, respectively). Cow serum calcium concentrations were affected by time, beginning to decrease 1 d precalving until 4 h postcalving, but this drop in serum calcium was more pronounced in TRT cows. Serum 5-HT and calcium concentrations were negatively correlated (r = −0.57) for the CON cows and positively correlated (r = 0.6) for the TRT cows. Maternal calcium and 5-HT decreased similarly due to precalving milking. Calcium and 5-HT concentrations were greater in colostrum collected from TRT cows milked precalving. Overall, calves had higher circulating 5-HT concentrations than cows, and calves born to TRT cows had increased 5-HT concentrations compared with the CON. Precalving milking could affect 5-HT synthesis within the mammary gland and therefore affect maternal 5-HT and calcium concentrations. Further research is needed in ruminants to assess the extent of 5-HT placental transfer, its role on pre- and postnatal development of the calf, the importance of its presence in colostrum, and potential long-term effects on calf health.  相似文献   

17.
A study was conducted to evaluate the potential effects of altering the proportion of dietary structural carbohydrate (SC) relative to nonfiber carbohydrate (NFC) pre- and postpartum on milk production and the circulating concentrations of hormones and metabolites. Dietary treatments were arranged as a 2 × 2 factorial, with 68 multiparous cows assigned to isoenergetic diets [114 MJ of metabolizable energy (ME)/cow per d] precalving; diets were either fresh pasture and pasture silage (PreP) or pasture and pasture silage supplemented with 3 kg dry matter (DM)/cow per d of a corn- and barley-based concentrate for 36 d prepartum (PreC). Final treatments were 13 or 32% DM NFC, respectively. After calving, cows within each prepartum diet were assigned to isoenergetic diets (179 MJ of ME/cow per d) differing in their SC and NFC content. Postcalving diets were either fresh pasture and pasture silage (PostP) or pasture and pasture silage supplemented with 5 kg DM/cow per d of a corn- and barley-based concentrate (PostC) until 35 d in milk. Final treatments were 18 and 38% DM NFC, respectively. Relative to day of calving (d 0), blood samples were collected at least weekly from d −28 to d 35. During the prepartum period, PreC cows had lower plasma urea, albumin, insulin-like growth factor-I, and Ca concentrations, but greater nonesterified fatty acid and Mg concentrations. There were no evident effects of prepartum diet on body weight or body condition score, milk yield, or milk composition. During the postpartum period, PostC cows had lower concentrations of plasma urea, β-hydroxybutyrate, and Ca, but greater concentrations of nonesterified fatty acids, glucose, insulin-like growth factor-I, and Mg. Postpartum metabolic differences in PostC cows were associated with increased milk protein production and reduced milk fat (yield and %). Results do not support a periparturient metabolic benefit to altering the SC to NFC ratio precalving, but imply an altered rumen fermentation, gluconeogenesis, and milk composition when dietary SC to NFC ratio is altered postcalving.  相似文献   

18.
Dairy cows experience a high incidence of disease and metabolic disorders in the weeks immediately following calving, but early and accurate diagnosis remains a challenge. Cows suffering from metritis, one common disease following calving, exhibit reduced milk yield and reproductive performance. However, afflicted cows show few overt signs of illness and frequently go unnoticed in the absence of veterinary examination. To determine whether changes in feeding behavior could be used to identify animals at risk for metritis, attendance at the feed alley was monitored continuously for 26 Holstein cows during the transition period, beginning 2 wk before and ending 3 wk after calving. Every 3 ± 1 d, cows were examined for metritis based on rectal body temperature and condition of vaginal discharge. Over the 3 wk of observations after calving, 69% of cows showed some signs of metritis. These cows spent on average 22 min/d less time at the feed alley during the transition period than did non-metritic cows. For every 10-min decrease in average daily feeding time, cows were twice as likely to be diagnosed with metritis. A threshold of 75 min of average daily feeding time was 89% sensitive and 62% specific for detection of acute metritis. In conclusion, reduced time at the feeder can be used to identify dairy cows at risk for metritis. More research is required to determine how soon before calving at-risk cows can be identified and whether these behavioral differences can also be used in the early diagnosis of other diseases or metabolic disorders.  相似文献   

19.
《Journal of dairy science》2021,104(10):11018-11034
Studies performed on individual research farms have reported that dairy cattle developing sole hemorrhages or sole ulcers in peak to mid lactation spent more time standing during the weeks around calving. The aim of this prospective observational longitudinal study was to evaluate whether this relationship is evident in commercial dairy herds. A convenience sample of 8 herds were visited every other week, and animals without previous severe horn lesions and deemed sound at 4 to 8 wk before calving were enrolled. Standing behavior was measured with data loggers attached to a rear leg, and standing time and duration of the longest standing bout were determined for each cow. Standing behavior was summarized into 3 periods: before (d −14 to −2), around (d −1 to 1), and after (d 2 to 14) calving. Average daily standing time and average daily longest standing bout were determined for each cow and period. Average daily standing time was normally distributed, with a mean ± standard deviation of 12.1 ± 1.6, 14.4 ± 2.2, and 13.8 ± 1.7 h/d for the 3 periods, respectively. Average daily longest standing bout was right skewed with a median of 3.6 h/d [interquartile range (IQR): 3.0 to 4.3; range: 1.7 to 12.1], 3.9 h/d (IQR: 3.1 to 4.8; range: 1.3 to 11.5), and 3.7 (IQR: 3.2 to 4.4; range: 1.5 to 11.7) h/d before, around, and after calving, respectively. Hoof trimming was performed 8 to 12 wk postpartum; hoof lesion data were summarized per cow, and the most serious injury of each type of lesion was noted. Sole hemorrhages or sole ulcers were found in 25 of 256 cows. Mixed-effect logistic regression models with herd as random effect were used to analyze the risk of developing sole hemorrhages and sole ulcers, using animals without hoof lesions as reference category. Separate models were fitted for the 2 standing behaviors, and for the periods before, around, and after calving. Change in standing behavior from before to after calving was also analyzed. Body condition score at calving, body condition score loss in early lactation, milk yield, parity, and days in milk at trimming were included as covariates. In this study, no evidence for an association was found between sole hemorrhages and sole ulcers and standing behavior before or around calving. Longer standing time and longer standing bouts after calving were associated with increased odds of developing sole hemorrhages and sole ulcers, as was an increase in standing bout duration from before to after calving. Animals with sole horn or white line lesions had higher unconditional sample odds of becoming lame (odds ratio = 2.5) and severely lame (odds ratio = 11.7) after calving, compared with animals with no registered lesions at trimming. Multiparous animals had higher lameness incidence, both before and after calving. Avoiding practices that exacerbate increases in standing time and standing bout duration in early lactation may reduce the incidence of sole hemorrhages and sole ulcers.  相似文献   

20.
Many cows have difficulty making the transition from pregnancy to lactation, as evidenced by the high incidence of disease that occurs in the weeks after calving. Changes in lying behavior can be used as an indicator of illness, yet no work to date has evaluated this relationship in dairy cows on pasture. The objectives of this study were to describe the lying behavior of grazing dairy cows during the first 3 wk after calving and determine the relationships between transition diseases and lying behavior. Our convenience sample included 227 multiparous and 47 primiparous Holstein cows from 6 commercial farms. Cows were recruited as they calved during the spring calving period. Electronic data loggers (Hobo Pendant G Acceleration, Onset Computer Corp., Pocasset, MA) recorded lying behavior at 1-min intervals. Diseases were recorded up to 21 d in milk, and cows were subsequently categorized into 3 health categories: (1) healthy, not lame and had no other signs of clinical (retained placenta, milk fever, metritis, mastitis) or subclinical (ketosis, hypocalcemia) postpartum diseases; (2) lame, identified as being clinically or severely lame with no other signs of clinical or subclinical postpartum disease; and (3) sick, diagnosed as having one or more clinical postpartum diseases (with or without a subclinical disease) but not lame. This last group was further divided into 2 groups: those that were diagnosed with a single clinical health event and those diagnosed with more than one clinical event. Lying behavior differed between primiparous and multiparous cows; primiparous cows divided their lying time into more bouts than did multiparous cows (9.7 ± 0.54 vs. 8.4 ± 0.26 bouts/d) and spent less time lying down than multiparous cows (7.5 ± 0.38 h/d vs. 8.5 ± 0.19 h/d). Lying behavior was also affected by illness; primiparous cows that developed more than one clinical disease, excluding lameness, spent more time lying, and tended to have longer lying bouts in the days following calving compared with healthy cows; multiparous severely lame cows spent more time lying down (1.7 h longer per day) compared with multiparous cows that were nonlame. Clinically lame cows had fewer lying bouts per day and these bouts were of longer duration than healthy nonlame cows. In summary, changes in lying behavior after calving were associated with postpartum health status in grazing dairy cows.  相似文献   

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