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1.
Dry period and early post-partum management are decisive factors for fertility in lactating dairy cows. Previous studies have shown that decreased dry matter intake (DMI) and increased non-esterified fatty acids (NEFA) negatively affect fertility and subsequent milk production. The traditional dry period decreases DMI prior to parturition, resulting in a decrease in energy intake. A negative energy balance increases NEFA concentration, and increased NEFA may impair the immune system, especially by decreasing neutrophil function prior to parturition. Earlier studies have shown that post-partum health disorders, including retained placenta and metritis, were correlated with periparturient neutrophil function. In addition, decreased DMI is also linked to a reduced body condition score (BCS) in dairy cows. These events in the periparturient period negatively affect fertility. Some manipulation, such as shortening the dry period, may be a solution to increased DMI in the periparturient period, preventing post-partum disorders and subsequent fertility issues. This article aims to explain the effects of shortening the dry period on reproduction and early post-partum treatments to improve fertility. In addition, timed artificial insemination protocols will be discussed for use during the post-partum period to improve fertility in dairy cows.  相似文献   

2.
The objective of this experiment was to study the effect of prepartum diets on dry matter intake (DMI) around parturition and on milk production in early lactation during a hot summer. Nine cows due to calve in July or August were assigned to two groups and fed either control (group C; four cows) or high‐concentrate (group H; five cows) diets to meet 110% of their energy requirements from 18 days before the expected calving date to parturition. The proportion of concentrate in the control diet was 35%, and that in the high‐concentrate diet was 45%. For 21 days after parturition, all cows were fed the same diets for lactation ad libitum. The DMI of cows in group H almost met their energy requirements. In group C, the DMI was decreased relative to group H and the concentration of plasma non‐esterified fatty acids was significantly higher (P < 0.05) before parturition. Therefore, the cows in group C were thought to be energy deficient before parturition. After parturition, there were no significant differences in DMI between the two groups. The milk yield of cows in group H tended to be higher than that of cows in group C at 21 days after parturition. Milk protein yield was significantly higher (P < 0.05) in group H 21 days after parturition relative to group C. There were no significant differences in milk composition between the two groups.  相似文献   

3.
Background: Residual feed intake(RFI) in dairy cattle typically calculated at peak lactation is a measure of feed efficiency independent of milk production level. The objective of this study was to evaluate differences in ruminal bacteria, biopolymer hydrolyzing enzyme activities, and overall performance between the most-and the leastefficient dairy cows during the peripartal period. Twenty multiparous Holstein dairy cows with daily ad libitum access to a total mixed ration from d-10 to d 60 relative to the calving date were used. Cows were classified into most-efficient(i.e. with low RFI, n = 10) and least-efficient(i.e. with high RFI, n = 10) based on a linear regression model involving dry matter intake(DMI), fat-corrected milk(FCM), changes in body weight(BW), and metabolic BW.Results: The most-efficient cows had ~ 2.6 kg/d lower DMI at wk 4, 6, 7, and 8 compared with the least-efficient cows. In addition, the most-efficient cows had greater relative abundance of total ruminal bacterial community during the peripartal period. Compared with the least-efficient cows, the most-efficient cows had 4-fold greater relative abundance of Succinivibrio dextrinosolvens at d-10 and d 10 around parturition and tended to have greater abundance of Fibrobacter succinogenes and Megaspheara elsdenii. In contrast, the relative abundance of Butyrivibrio proteoclasticus and Streptococcus bovis was lower and Succinimonas amylolytica and Prevotella bryantii tended to be lower in the most-efficient cows around calving. During the peripartal period, the most-efficient cows had lower enzymatic activities of cellulase, amylase, and protease compared with the least-efficient cows.Conclusions: The results suggest that shifts in ruminal bacteria and digestive enzyme activities during the peripartal period could, at least in part, be part of the mechanism associated with better feed efficiency in dairy cows.  相似文献   

4.
Multiparous (n = 26) and primiparous (n = 18) Holstein cows were fed prepartum and postpartum total mixed diets that were, or were not, supplemented with a yeast culture (YC) for approximately 23 d prepartum and 56 d postpartum. Multiparous cows supplemented with YC selected a prepartum diet higher in CP than did unsupplemented cows, although prepartum performance of cows of both parities, as assessed by DMI and measures of body status, was not influenced by YC. The extent of the prepartum DMI depression was not influenced by YC supplementation in cows of either parity. An intake behavior study with six multiparous cows suggested that cows supplemented with YC exhibited repeated diurnal feed intake patterns until approximately 7 d prepartum, vs 10 d prepartum for unsupplemented cows. Cows of both parities supplemented with YC had numerically higher DMI and production of milk and milk components, although only DMI for multiparous cows and milk production for primiparous cows approached statistical significance. Intake behavior results suggested that cows supplemented with YC achieved repeated diurnal feed intake patterns by approximately 14 d postpartum, vs 20 d postpartum for unsupplemented cows. Concentrations of ruminal metabolites and pH did not differ between treatments, although ruminal fluid collection occurred while diurnal feed intake patterns were repeated (regular). Overall, our results can be interpreted to support a trend toward a modest postpartum improvement in performance of primiparous and multiparous cows supplemented with this YC for 23 d prepartum and 56 d postpartum. However, primiparous cows seemed to achieve this modest overall improvement primarily through enhanced postpartum DMI, whereas in multiparous cows it was due almost equally to enhanced postpartum DMI and higher energy density of the diet.  相似文献   

5.
OBJECTIVE: To determine whether numbers of coliform bacteria in feces of dairy cattle changed during the periparturient period and whether fluctuations were associated with changes in dry-matter intake. ANIMALS: 12 healthy Holstein cows. PROCEDURE: Fecal samples were collected on a semi-regular basis (i.e., 3 to 7 times/wk) beginning 4 to 6 weeks before the anticipated parturition date and continuing through the third day (5 cows) or second week (7 cows) after parturition, and total numbers of fecal coliform bacteria were determined. Daily feed intake of 7 cows was monitored. RESULTS: For 11 cows, fecal coliform bacterial counts between 34 and 25 days prior to parturition were low and relatively constant (< 102 change in number of bacteria). Coliform bacteria were not detected in 4 to 8% of fecal samples from 10 cows. All cows had a 10(4) to 10(7) increase in number of colony forming units/g of feces near the time of parturition. Number of fecal coliform bacteria peaked within 7 days of parturition in 9 cows and within 12 days of parturition in 3. Number of fecal coliform bacteria was not correlated with feed intake. CONCLUSIONS AND CLINICAL RELEVANCE: Cows may have large increases in fecal coliform bacteria count during the periparturient period; however, periparturient cows do not continually shed high numbers of coliform bacteria, and coliform bacteria may not always be detectable by conventional culture methods. Changes in fecal coliform bacteria count did not correlate with changes in dry-matter intake.  相似文献   

6.
Eight pregnant heifers (primiparous cows) and seven pregnant cows in their second, third and forth pregnancies (multiparous cows) were assigned to two groups and fed either a low calcium (Ca) diet (Ca, 0.46%) or a high Ca diet (Ca, 0.86%) ad libitum from 3 weeks before the expected calving date to 3 days after parturition. All cows were examined for a change in dry matter intake (DMI), plasma minerals and bone turnover around parturition. The dietary Ca level did not affect the DMI in both primiparous and multiparous cows. The DMI of primiparous cows was significantly lower than that of multiparous cows (P < 0.05) in both the low and high dietary Ca groups. The dietary Ca level did not affect the concentrations of plasma Ca, phosphorus, magnesium and parathyroid hormone throughout the experimental period. Plasma phosphorus in primiparous cows was significantly higher (P < 0.05) than that of multiparous cows around parturition. Plasma Ca and magnesium tended to be higher (P < 0.10) in primiparous cows. The dietary Ca level did not affect the plasma osteocalcin (OC) level measured as bone formation or the urinary deoxypyridinoline (DPD) excretion measured as bone resorption before parturition in both primiparous and multiparous cows. After parturition, the plasma OC level was lower than it was before parturition in multiparous cows fed a low Ca diet, and in primiparous cows. There were no significant differences in urinary DPD excretion between each group before and after parturition. Both the plasma OC level and urinary DPD excretion of primiparous cows were significantly higher than those of multiparous cows in both the low and high dietary Ca groups.  相似文献   

7.
A study was made of the influence of low and high calcium intakes at two feeding levels (experiments 1 and 2), and of different magnesium intakes (experiment 3) during the dry period, on the cellular resorptive activity in bone of dairy cows at parturition. In experiment 1 (26 cows) the feed intake was 1.12 times maintenance and the calcium intake was either 13.0 g d-1 or 83.5 g d-1. In experiment 2 (33 cows) the feed intake was 1.9 times maintenance and the calcium intake was either 26.4 g d-1 or 87.2 g d-1. In experiment 3 the cows feed intake was 1.4 times maintenance, the calcium intake was 71 to 72 g d-1 and the magnesium intake was either 16.6 g d-1 or 71.0 g d-1. Bone biopsies were taken from the tuber coxae between three and eight hours after parturition. In experiment 1 the cellular resorptive activity in bone from older cows was higher in the cows receiving the low calcium diet. In experiment 2 the differences between the bone resorptive activities of the two groups were small. In experiment 3 the bone resorptive activity was lower in the cows with a deficient supply of magnesium. There were significant relationships in young cows, but not in older cows, between the cellular resorptive activity in bone and the rate of calcium mobilisation measured biochemically. These results suggest that in older dairy cows bone resorption makes only a minor contribution to the total rate of calcium mobilisation at parturition and is therefore of minor importance for the prevention of periparturient hypocalcaemia.  相似文献   

8.
This study was designed to evaluate if the immunosuppression typically observed during the immediate periparturient period (3 weeks before and after calving) in dairy cows influences the effectiveness of diagnostic tests for the detection of Johne's disease; and, if providing additional energy to the cows during this period would minimize any immunosuppressive effects. Twelve dairy cows naturally infected with Mycobacterium paratuberculosis were fitted with rumen cannulas in late gestation and assigned to treatment groups: control, n = 6; or stuffed, n = 6. Cows in the control group were allowed to consume feed ad libitum. Cows assigned to the stuffed treatment group were also fed ad libitum but received additional total mixed ration by manually stuffing their rumens with refused feed to maintain a dry matter intake of 2% body weight/day before calving and 2.5% body weight/day after calving. Parturition had a significant impact on immune function with significant reductions in M. paratuberculosis-specific antibodies detected in the serum and milk regardless of treatment group. Similarly, in vitro immunoglobulin production was decreased at calving for both treatment groups. In addition, stuffing cows modulated cell-mediated immune function by reducing antigen-specific lymphocyte proliferation and interferon-gamma production after calving. Shedding of M. paratuberculosis in the milk was apparent in 58% (7/12) of cows after parturition with no difference noted between control and stuffed animals. Parturition had no major effect on fecal shedding of cows regardless of treatment. These data suggest that parturition had a significant effect on immune function parameters including diagnostic tests for paratuberculosis. Furthermore, providing additional energy to cows with Johne's disease did not preclude immunosuppressive effects during the periparturient period.  相似文献   

9.
奶牛养殖过程中,围产期被认为是最重要的时期之一,在该时期奶牛从干奶状态转为泌乳状态,生理上所受的应激造成奶牛泌乳早期采食量降低,易发生能量负平衡.此外,奶牛生产性能和繁殖性能也会降低,并常常伴有一些围产期疾病的发生,如脂肪肝、酮症、乳房炎等.胆碱能影响奶牛的生产与繁殖性能,参与奶牛的脂肪代谢,可降低脂肪肝发生率,提高免疫性能.对围产期奶牛饲喂过瘤胃保护胆碱(rumen protected choline,RPC),可改善奶牛机体代谢,增加小肠胆碱供应,进而提高奶产量、改善乳成分、缓解脂肪肝、减少围产期疾病的发生.本文综述了RPC对围产期奶牛干物质采食量、生产性能、乳成分以及健康状况的影响,旨在为围产期奶牛的养殖提供理论参考依据.  相似文献   

10.
Recent studies have shown significant associations between prepartum energy status and postpartum fertility in dairy cows; therefore, the assessment of energy status by blood metabolites and metabolic hormones and suitable improvement of management during the prepartum period may enhance reproductive performance. Rumen fill score (RFS) is associated with feed intake; however, it is unknown whether RFS is also related to blood parameters. Therefore, this study investigated the relationship between RFS and energy status during the prepartum period, and their associations with conception at first artificial insemination (AI) after parturition. In 42 multiparous Holstein cows, RFS assessment and blood sampling were carried out twice a week during 3 weeks of the peripartum period. Ovarian cycles until AI were evaluated by measuring milk progesterone levels. Before calving, positive correlations were observed between RFS and total cholesterol, and RFS did not change in pregnant cows at first AI after parturition, whereas in non‐pregnant cows, RFS decreased gradually as the calving day approached. After calving, non‐pregnant cows showed lower energy status compared with pregnant cows, and some non‐pregnant cows showed anovulation and cessation of estrous cycle. In conclusion, RFS during the close‐up dry period is related to real‐time energy status, and is associated with postpartum energy status and conception at first AI in dairy cows. © 2016 Japanese Society of Animal Science  相似文献   

11.
In a previous paper we have proposed a new concept of a model for the prediction of feed intake by Holstein Friesian dairy cows (Zom et al., 2011). This model predicts feed intake from feed composition and digestibility and the cow's lactation number, stage of lactation and pregnancy. Contrary to many other often used models, this does not include animal performance (milk yield, bodyweight) to predict feed intake. However, BW and MY are highly correlated with DMI. Therefore, the objective of present study was to evaluate the accuracy and robustness of the novel feed intake model and to compare its accuracy and robustness with four other commonly used models for the prediction of feed intake.An evaluation was performed using an independent dataset containing 8974 weekly means of DMI from 348 individual cows observed in 6 feeding experiments including a wide range of diets and management practices was used in this study. Sub-datasets were formed by combining the DMI data by experiment, lactation number, lactation week, and maize silage to grass silage ratios in order to compare the accuracy of the intake models for different feeding practices and groups of cows using mean square prediction error (MSPE) and relative prediction error (RPE) as criteria.The novel model was most accurate as indicated by the MSPEs and RPEs for the whole dataset and the most of the sub-datasets. The results prove that the model of Zom et al. (2011) is able to predict DMI without the use of milk yield or body weight as inputs. It was concluded that novel model was robust and can be applied to various diets and feeding management situations in lactating HF cows.  相似文献   

12.
The objectives of this study were to investigate the associations between peripheral blood neutrophil (PMN) function, energy status, and uterine health in periparturient dairy cows. Data were collected from 83 multiparous Holstein cows. Blood samples for PMN function determination were collected weekly from 1 week prior to calving (week -1) through 4 weeks after calving and again at 8 weeks after calving. Energy metabolites were measured and dry matter intake (DMI) was determined from weeks -2 to 5 to evaluate energy status of cows during the periparturient period. All cows were examined for uterine health disorders. Blood PMN killing ability was evaluated by determining myeloperoxidase activity and cytochrome c reduction activity in isolated blood PMN's. For cows that were diagnosed with puerperal metritis and subclinical (SC) endometritis and puerperal metritis, blood PMN functions were significantly (P<0.05) impaired during the periparturient period, compared to cows with normal uterine health. Cows with subclinical endometritis and puerperal metritis or SC endometritis also had significantly (P<0.01) higher NEFA and significantly (P<0.001) lower DMI during the periparturient period, and significantly (P<0.05) higher BHBA during early lactation, compared to cows with normal uterine health. Neutrophil function was also significantly (P<0.01) impaired in cows with peripartum negative energy balance, which was characterized by elevated blood levels of NEFA and decreased DMI. Decreased PMN function and energy balance were associated with uterine health disorders and the decreases in PMN function and energy balance occurred prior to parturition and prior to the detection of these uterine disorders.  相似文献   

13.
The objectives of this study were to quantify the phenotypic variation in residual feed intake (RFI) in pregnant beef heifers offered a grass silage diet and to characterize their productivity. Seventy-three pregnant (mean gestation d 198, SD = 27 d) Simmental and Simmental × Holstein-Friesian heifers (mean initial BW 548, SD = 47.5 kg) were offered grass silage ad libitum. Heifer DMI, BW, BCS, skeletal measurements, ultrasonic fat and muscle depth, visual muscularity score, rumen fermentation, total tract digestibility, blood metabolite and hematology variables, feeding, and activity behavior were measured during an 84-d feed intake study. After parturition calf birth weight, calving difficulty, cow serum IgG, hematology variables, and calf humoral immune status were measured. In a subset of cows (n = 28), DMI, milk yield and various body composition variables were also measured approximately 3 wk postpartum. Phenotypic RFI was calculated for each animal as the difference between actual DMI and expected DMI. Expected DMI was computed for each animal by regressing average daily DMI on conceptus-adjusted mean BW(0.75) and conceptus-adjusted ADG over an 84-d period. Within breed, heifers were ranked by RFI into low (efficient), medium, and high (inefficient) groups by dividing them into thirds. Heifers with high RFI had 8.8 and 17.1% greater (P < 0.001) DMI than medium and low RFI groups, respectively. The RFI groups did not differ in ADG or BW (P > 0.05). Residual feed intake was positively correlated with DMI (r = 0.85) but not with feed conversion ratio, ADG, or BW. The RFI groups did not differ (P > 0.05) in skeletal size, BCS, ultrasonic fat depth, total tract digestibility, calf birth weight, calving difficulty, serum IgG concentrations, or milk yield. Visual muscularity scores, initial test and postpartum ultrasonic muscle depth were negatively correlated with RFI (P < 0.05). Including mean ultrasonic muscle depth into the base RFI regression model increased its R(2) (0.29 to 0.38). Pearson rank correlation between RFI and muscle-adjusted RFI was 0.93. The results show that efficient RFI heifers consumed less feed without any compromise in growth, body composition, or maternal traits measured.  相似文献   

14.
Two experiments were conducted to determine effects of oleamide on feed intake and ruminal fatty acids when the oleamide was introduced in the feed vs through a ruminal fistula (Exp. 1) or the oleamide was fed for an extended (9-wk) length of time (Exp. 2). In Exp. 1, four nonlactating Holstein cows, each fitted with a ruminal cannula, were fed four diets in a 4 x 4 Latin square design. Each period lasted 2 wk. Diets consisted of 48% corn silage and 52% concentrate on a DM basis. One diet contained no added fat (control) and a second diet contained 4.2% oleic acid. The remaining two diets were designed to expose cows to 4.2% amide (as oleamide) either through the feed (AF) or by administering oleamide into the rumen (AR) each day through the ruminal cannula. The AF diet reduced DMI similarly to results reported previously for lactating dairy cows and sheep. Intake of the oleic acid diet was intermediate between the control and AF diets. Dry matter intake was reduced by AR similarly to the AF diet. The acetate:propionate ratio in samples of ruminal contents was reduced by oleic acid but not by AF or AR. In Exp. 2, 12 steers were divided into three equal groups of two Angus and two Simmental x Angus crosses, and each group was assigned a diet containing either no added fat (control), 4% oleamide, or 4% high-oleic canola oil. All steers had ad libitum access to feed and water. Dry matter intake by steers fed the canola oil diet was not different from that by steers fed the control diet when averaged over the first 3 wk, the last 3 wk, or over the entire 9-wk study. Oleamide reduced DMI 4 kg/d over the first 3 wk of the study. However, DMI of the oleamide diet consistently increased over the 9-wk study, resulting in wk 7 to 9 DMI that was not different from that of steers fed the control diet. These results show that the reduction in feed intake when oleamide is added to cattle rations can be attributed more to physiological responses than to an undesirable unique taste or odor of the oleamide. In finishing beef steers, the decreased intake induced by oleamide was most severe during the first 1 or 2 wk of feeding but gradually lessened over time until it nearly returned to normal by wk 9.  相似文献   

15.
The influence of a low and a high prepartum calcium (Ca) intake on Ca mobilization rate around parturition was studied in 44 dairy cows fed a ration sufficient for 1.90 times maintenance requirements during the dry period. The plasma Ca level declined on the day of parturition in the group fed the low Ca intake (LCa: 26.4 g/d) as well as in the group fed the high Ca intake (HCa: 87.2 g/d). Plasma Ca levels of the HCa group were lower at parturition, and in this group 1 cow had milk fever after parturition. In the HCa group 6 cows had a plasma Ca level less than or equal to 2.0 mmol/l at parturition and/or 10 h post-partum (pp), versus 1 cow in the LCa group. Na2EDTA was intravenously infused at 10 h pp to induce hypocalcaemia to a level of plasma Ca not bound to EDTA of approximately 1.0 mmol/l. The LCa groups tended to require more Na2EDTA than the HCa groups, however the difference was significant only in the younger cows. After the Na2EDTA infusion 7 cows of the HCa group and 1 of the LCa group did not recover spontaneously and needed to be treated. The mean plasma PTH levels of the LCa group ante-partum were slightly higher than those of the HCa group. The Ca level of the prepartum ration did not influence urinary hydroxyproline excretion, which suggests that the Ca intake of 26.4 g/d was too high to stimulate bone turnover. Comparison of the present results with those of an earlier experiment in which the prepartum Ca intake at a low feeding level (1.12 times maintenance) was studied, led to the conclusion that higher prepartum feed intake has a clear negative influence on Ca homeostasis around parturition.  相似文献   

16.
The objective of this study was to determine the effect of feeding strategies in cows that allowed BW loss followed by BW gain on the efficiency of feed utilization for calf production. The first treatment (H-H-H) was designed to maintain body condition score of mature cows at 5.5 from the second trimester until the subsequent breeding season. The second treatment (L-H-H) was designed such that cows lost body condition during the second trimester and regained it during the third trimester and were equal in weight and body condition scores at parturition to cows assigned to the H-H-H treatment. The third treatment (L-L-H) was designed such that cows lost body condition during the second trimester and gained body condition after 28 d of lactation so that they would be equal to the other two treatments at breeding. Forty-eight cows were assigned to each treatment. Total DMI over the entire study did not differ between the H-H-H and L-H-H treatments (P = 0.23), but intake on both were higher than the L-L-H treatment (P < 0.001). Calf birth weight of the H-H-H treatment did not differ (P = 0.43) from those of L-H-H, but both groups were greater than those of the L-L-H (P < or = 0.002) treatment. At 28 d of age, H-H-H (P = 0.008) and L-H-H (P = 0.007) calves weighed more than the L-L-H calves, but at 58 d of age there was no difference in calf BW among the treatments (P = 0.81). The percentage of cows that were diagnosed pregnant at weaning with their next calf did not differ (P = 0.71) among treatments. We interpret the results of this study to suggest that weight cycling in mature beef cows may be a viable management tool for decreasing food costs.  相似文献   

17.
将年龄、胎次相同,年产奶量大于5000kg的围产期健康奶牛30头随机分为3组,每组10头。按照中国奶牛饲养标准(2000),低能组饲喂减少20%日粮(能量摄入80%组),对照组饲喂标准日粮(能量摄入100%组),高能组饲喂增加20%日粮(能量摄入120%组),试验从产前14天开始至产后28天结束,产后各组奶牛均饲喂标准日粮。采用半定量RTPCR方法检测了不同能量摄入对围产期奶牛脂肪组织胰岛素受体(InsR)mRNA丰度的影响。结果表明:各组脂肪InsRmRNA相对表达量从产前14天至产后28天均呈现先升高后降低的趋势,产后14天达到最大值,且产后高于产前;低能组产前InsRmRNA相对表达量低于高能组和正常组,产后1天至产后28天高于高能组和正常组,产后14天显著高于高能组(P<0.01)。可见,干乳期低能饲喂奶牛,产后脂肪InsRmRNA表达增加,提示产前适当降低能量摄入水平,有利于胰岛素抑制泌乳初期脂肪动员作用的发挥。  相似文献   

18.
The objective of this study was to determine the effect of partial replacement of barley grain with beet pulp (BP) on dry matter intake (DMI), ruminal fermentation, plasma concentration of metabolites and milk yield of transition dairy cows. Twenty‐four multiparous Holstein cows [735 ± 26 kg of body weights and 3.5 ± 0.05 of body condition score (BCS)] were used in a randomized complete block design. Cows were assigned randomly on day 28 relative to expected parturition date to one of three treatments containing (i) 0% BP, (ii) 25% BP or (iii) 50% BP substituted for barley grain on a DM basis. During the pre‐partum period, DMI and energy intake were greater (P < 0.01) in cows fed the BP diet compared with cows fed the barley grain diet. During the post‐partum period, substituting BP for barley grain caused a response in DMI and energy intake, with the highest amount for the 25% BP diet and lowest for the 50% BP diet (P < 0.01). Milk yield was lowest (P < 0.01) for 50% BP diet than the other treatments. During the post‐partum period, cows fed the 50% BP diets had greater rumen pH, molar proportion of butyrate and acetate: propionate ratio (P < 0.01) in the rumen compared with cows fed the 0% BP diets. In addition, cows fed the BP diets had greater (P < 0.01) plasma β‐hydroxybutyrate and lower plasma glucose (P < 0.05) and blood urinary nitrogen (BUN) (P < 0.01) concentrations than cows fed the barley grain diets. Results showed that substituting BP for barley grain was effective in increasing DMI, but it did not have a significant effect on net energy balance during the post‐partum period. However, replacing BP for barley grain at 50% had adverse effects on DMI, milk yield and metabolic status, as indicated by key blood metabolite concentrations.  相似文献   

19.
干奶期不同能量摄入水平对产后奶牛生产性能的影响   总被引：3，自引：2，他引：3  
将围产期健康奶牛30头随机分为3组．分别于产前28d开始饲喂NRC标准日粮（能量摄入100％组）、NRC标准增加20％日粮（能量摄入120％组）和NRC标准减少20％日粮（能量摄入80％组）．产后各组奶牛均饲喂标准日粮，至产后56d结束，观察干奶期不同能量摄入水平对产后奶牛生产性能的影响。结果表明，高能量组奶牛产后干物质采食量和产奶量均显著低于其他2组，并且体质量消耗明显。由此认为，干奶期能量摄入水平是影响和调节产后干物质摄入量、产乳量和能量平衡状态的重要因素。  相似文献   

20.
选用32头干奶后期荷斯坦牛,按照年龄、体重、胎次和上个周期产奶量相同或相近的原则,随机分成4个处理组,研究在日粮中添加草香味调味剂、焦糖味调味剂和果香味调味剂（添加比例100g/t TMR日粮）,对奶牛采食量、产后体重恢复和体况评分的影响。结果表明,在日粮中添加调味剂对围产期奶牛产前和产后的干物质采食量有提高的趋势,其中产前日粮添加调味剂A（草香味）和调味剂B（焦糖味）可以显著提高奶牛的干物质采食量（P〈0.05）;在日粮中添加调味剂对围产期奶牛产后体重的恢复有促进作用,其中添加调味剂B（焦糖味）组奶牛在产后28天和42天的测定值显示,可以显著影响围产期奶牛产后的体重恢复（P〈0.05）;在日粮中添加调味剂对围产期奶牛产后体况的恢复有促进作用,其中在奶牛产后14天的测定值显示,添加调味剂B（焦糖味）可以显著改善奶牛的体况（P〈0.05）;在产后28天,添加调味剂B（焦糖味）和调味剂C（果香味）可以显著改善奶牛的体况（P〈0.05）;在产后42天,添加调味剂A（草香味）、调味剂B（焦糖味）和调味剂C（果香味）都可以显著改善奶牛的体况（P〈0.05）。即在围产期奶牛日粮中添加不同风味的调味剂,都可以提高奶牛的干物质采食量,促进奶牛产后体重和体况的恢复,其中焦糖味调味剂的效果最为明显。  相似文献   

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