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The impact of closely controlled energy management during the dry period upon general peripartum metabolism and the subsequent lactation was evaluated in multiparous dairy cows. Eight lactating, pregnant Holstein cows were paired according to current milk production and body condition score and assigned to either the control or the stair-step compensatory nutrition (SSCN) regimen 16 weeks prior to expected calving date. Control cows were fed according to National Research Council [National Research Council., 2001. Nutrient Requirements of Dairy Cattle. 7th rev. ed. Natl. Acad. Sci., Washington, DC.] recommendations and for ad libitum intake during late lactation and the far-off dry period. The SSCN cows were subjected to dietary energy restriction [80% of net energy for lactation requirements (NEL)] during late lactation in order to maintain body weight, followed by realimentation (130% of NEL) during the far-off dry period to induce a compensatory response. A common diet was fed thereafter. The SSCN cows gained less body condition during late lactation and tended to gain more body condition during the far-off dry and transition periods than control cows. There was no difference in dry matter intake during the prepartum transition period and early lactation. Milk yield was not affected by treatment. Serum nonesterified fatty acids (NEFA) were not altered by dietary treatment during late lactation and the dry period; however NEFA were lower in SSCN cows at week 4 of the subsequent lactation. Serum insulin was higher in SSCN cows 8 weeks prior to parturition (end of restriction), tended to be higher at 4 weeks (end of realimentation) before calving, and was also higher at week 12 of early lactation. An SSCN regimen stimulated body condition gain of mature dairy cows during the dry period, did not affect periparturient nutrient metabolism, and led to modest improvements in metabolic parameters later in the subsequent lactation. 相似文献
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Wittek T Fürll M Constable PD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(4):574-580
Left displaced abomasum (LDA) and abomasal volvulus (AV) occur most commonly in postparturient dairy cows. Our main hypothesis was that endotoxemia occurred more frequently in the peripheral blood of cows with LDA or AV than in healthy cows because increased luminal pressure in AV or LDA, or the presence of a hemorrhagic strangulating obstruction in AV, may have injured the abomasal mucosa, thereby facilitating translocation of luminal endotoxin into the circulation. Therefore, our main objective was to compare the prevalence and magnitude of endotoxemia in healthy postparturient cows with the prevalence and magnitude of endotoxemia in cows with AV and LDA. We examined 60 adult dairy cows in early lactation that were diagnosed with AV (n = 15) or LDA (n = 15) or were healthy on physical examination (control group, n = 30). Jugular venous blood was obtained from cows in all 3 groups, and right gastroepiploic venous blood was obtained during surgical correction of AV and LDA immediately after repositioning of the abomasum. Platelet-rich plasma endotoxin concentrations were measured with a chromogenic limulus amoebocyte lysate assay. Endotoxin was detected in jugular vein plasma in 50% (15/30) of control cows; however, the prevalence of endotoxemia was significantly lower (P < .05) in cows with AV (7%, 1/15) or LDA (20%, 3/15). Endotoxin was detected simultaneously in right gastroepiploic and jugular vein plasma in only 1 cow with LDA and 0 cows with AV. Contrary to our hypothesis, we conclude that endotoxemia is infrequently present in postparturient dairy cows with AV or LDA. 相似文献
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The objective of this study was to determine risk factors for udder edema (case–control study) and to evaluate the association of udder edema in primiparous Holstein cows with their lactation performance (cohort study). Values for the first 10 test day for milk yield, fat, protein, and somatic cell counts (SCC) linear score as well as mature equivalent (ME) 305 days milk yield, fat, protein, SCC linear score, and incidences of periparturient diseases from a computerized farm recording system were compared between primiparous cows with and without udder edema. Data consisted of 118 dairy heifers with udder edema, induced for parturition, and treated with diuretics and 889 control heifers that received no treatment. Primiparous cows giving birth to male calves, were 1.72 (1.01, 3.24; 95% CI) times more likely to develop udder edema than cows giving birth to female calves. Primiparous cows calving in winter season were 3.68 (1.09, 12.5; 95% CI) times more likely to develop udder edema than cows calving in summer. For each extra 10 cm in height the odds of udder edemas was 1.23 (1.03, 1.47; 95% CI). The first test day DHIA milk yield was lower in cows that developed udder edema (3.6 kg/day) than in normal cows. However, the subsequent test days and ME measurements were not statistically different between groups. Cows with udder edema were 1.62 (1.18, 2.14; 95% CI) times more likely to develop udder edema in the second lactation than control animals. It is concluded that the gender of the offspring, calving season and height at parturition were significant risk factors for udder edema. Only milk yield on the first DHIA test day was lower in cows with udder edema than in cows without udder edema. 相似文献
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为探讨脂联素(ADPN)与激素敏感脂肪酶(HSL)对围产期奶牛脂肪动员的影响及其相互关系,随机选取围产期健康奶牛10头,分别于产前28天、产前14天、产后1天、产后14天和产后28天,应用荧光定量RT-PCR法检测其脂肪组织ADPN mRNA和HSL mRNA丰度。结果表明:在围产期,随着分娩日龄的临近,其脂肪组织的HSL mRNA水平随着ADPN mRNA丰度的降低而下降,产后则随其升高而上升,初步推测脂联素可能是通过调控脂肪HSL mRNA的表达和分泌来调节围产期奶牛脂肪的。 相似文献
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Calfhood diseases have a major impact on the economic viability of cattle operations. This is the first in a three part review series on calf health from birth to weaning, focusing on preventive measures. The review considers both pre- and periparturient management factors influencing calf health, colostrum management in beef and dairy calves and further nutrition and weaning in dairy calves. 相似文献
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An investigation was carried out to assess the effects of weather on the occurrence and magnitude of the periparturient rise
(PPR) in trichostrongylid nematode egg output in breeding Dorper ewes. The study was conducted over three breeding seasons
on a ranch in the semi-arid area of Kajiado District in Kenya between June 1999 and December 2001. During each breeding season
20 ewes randomly selected from the breeding stock and 20 others selected from the unmated yearlings were monitored for faecal
strongyle egg counts every 3 weeks. The lambing seasons were timed to coincide with the onset of the short rains (October–November
1999), the mid-short rains (November–December 2000) and the end of the dry season (September–October 2001). In each season
higher egg outputs were recorded in the peri-parturient ewes compared to the unmated yearlings. The highest PPR occurred in
September 2001, when lambing coincided with the end of the dry season, possibly as a result of maturation of hypobiotic larvae.
The lowest PPR occurred in November 2000 when the onset of lambing coincided with the mid-short rains, possibly owing to low
pasture infectivity associated with a long dry spell between January and October of the same year. The results of this study
indicate that PPR occurred when lambing coincided with both the wet and the dry seasons. However, the magnitude was greatly
influenced by the season when lambing occurred. It was also influenced by resumption of development of hypobiotic larvae and
the nutritional status of the ewes. Not only should control of gastrointestinal nematode parasites in this area aim at preventing
the occurrence of PPR by treating ewes 2–3 weeks before they are to lamb and during lactation, but the anthelmintic used must
also eliminate hypobiotic larvae. In addition, the animals must be given supplementary feeding during this period. 相似文献
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Forty multiparous Holstein dry cows on d 21 prepartum were randomly allocated to four blocks of 10 cows to examine the effects of reducing the dietary cation–anion difference (DCAD) on calcium homeostasis, acid–base balance, health status, and subsequent lactation performance. The reduced DCADs (Na + K − Cl − S, mEq/kg DM) of + 150,+ 50, − 50, and − 150 were obtained by addition of anionic salts. Reducing DCAD resulted in mild metabolic acidosis as indicated by the sharp decline in urinary pH, and minor reductions in blood pH and HCO3− concentration. Greater plasma calcium concentration was observed in cows fed diets of − 50 and − 150 DCAD (P < 0.05) than those on + 50 and + 150 DCAD diets. The nadir of plasma calcium level on the day of calving was lower (P < 0.05) than the highest level on d 14 prepartum (8.33 vs. 9.30 mg/dL). Composite colostrum calcium concentration was decreased (P < 0.05) with time on d 1 relative to d 2 postpartum (0.212 vs. 0.174%), and feeding of diet − 150 DCAD induced higher (P < 0.05) composite colostrum calcium content than other three DCAD diets. No case of milk fever occurred for any diets, but feeding the two negative DCAD diets reduced (P < 0.05) retained placenta incidence compared with diet of + 150 DCAD. Dry matter intake, milk yield and compositions of fat, protein, and lactose were non-significantly affected (P > 0.05) by dietary treatments. In conclusion, urinary pH is an effective indicator of extracellular fluid acid–base balance, and feeding negative DCAD in late gestation period is beneficial for dairy cows in blood calcium homeostasis and improvement of health status. 相似文献
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Maintaining yearly foal production is important for the economic success of the broodmare, and this requires breeding to occur as quickly postpartum as possible. The initial postpartum estrus occurs within 5–20 days postpartum, whereas the uterus is still undergoing repair from tissue alterations during pregnancy and parturition, a process known as involution. Attempts have been made to hasten this process, but with minimal success. Mycobacterium cell wall fraction (MCWF) is an immunomodulator that has been shown to reduce bacterial growth and alter aspects of the immune response to breeding, but it is unknown if MCWF hastens the process of involution. Therefore, the objectives of this study were to (1) investigate the effect of MCWF on tissue remodeling, (2) assess the effect of MCWF on the local immune system of the uterus, and (3) determine the optimal treatment interval needed for these processes to occur. We hypothesize that repeated treatments of MCWF postpartum will hasten the process of involution. To study this, 16 pregnant mares of mixed breeds were evaluated postpartum. Control mares (n = 4) received 1.5 mL lactated Ringer’s solution intravenously on Day 1 (Day 0 = day of parturition) postpartum and again on Day 7, whereas treated mares either received 1.5 mL Settle intravenously on Day 1 and Day 7 (TX1; n = 6) or 1.5 mL Settle intravenously on Day 1 and then every 3 days until ovulation was detected (TX2; n = 6) and then evaluated until 15 days postpartum. Mares were assessed every 3 days for clinical, immunologic, and histologic parameters. Clinical parameters were assessed with transrectal ultrasonography and included ovarian activity, uterine fluid retention, and measurement of the uterine diameter, in addition to endometrial culture. Immunologic parameters included endometrial biopsies for quantitative polymerase chain reaction for expression of various cytokines (interleukin [IL]-1β, IL-1RN, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor [TNF], interferon [IFN]-γ, and granulocyte-macrophage colony-stimulating factor) in addition to endometrial cytology. Formalin-fixed endometrial biopsies were histologically assessed for the retention of microcaruncles, dilation of endometrial glands, and inflammation of the mucosa, stratum compactum, and spongiosum. Statistics were performed using SAS 9.4, using a mixed model for repeated measures with mare and treatment as a random effect. All post-hoc analysis was done using a Tukey’s honestly significant difference test. Involution was considered complete by Day 15 postpartum in all mares, and the day postpartum had a significant effect on almost all parameters investigated, indicating the immunologic process of involution. Treatment with MCWF decreased the magnitude of bacterial growth in addition to time to negative culture. In addition, MCWF increased the expression of IL-1β, IFNγ, and TNF. Although minimal treatment effect was noted histologically, a decrease in mucosal inflammation was seen in MCWF-treated mares. In conclusion, involution appears to be influenced by the immune system. In addition, MCWF appears to have a bactericidal effect on the postpartum mare, and this may be because of an increase in proinflammatory cytokines. It is unknown if this bactericidal property will improve fertility on the first estrous cycle postpartum, and future studies are needed to determine this. 相似文献
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The results of numerous studies on postpartum uterine involution, ovarian activity and endocrinological changes before, during and after normal and abnormal parturitions, have been reviewed in this article. Most studies have shown that abnormal parturition is the main factor which delays completion of uterine involution and occurrence of the first estrous cycle post partum. The reviewed reports also indicated that any interference (corticosteroid injection, overiectomy, etc.) with normal synchronized hormonal changes of parturition can increase the incidence of retained fetal membrane. Reports on the use of hormonal treatments and their effects on the elimination of bacterial infection, rate of uterine involution and the resumption of ovulation activity are conflicting. It is suggested that the use of natural substances such as lipopolysaccharide of E. coli, serum or hyperimmune serum, extracts of poly morphonuclear leucocytes and/or macrophage-granulocyte Colony Stimulating Factor as treatments of postpartum uterine infection may play an important role in the completion of uterine involution and the commencement of estrous cycle . 相似文献
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本试验目的是研究缓释钙弹丸博威钙对预防奶牛低血钙的影响。选择二胎及以上胎次的健康母牛30头,根据配对原则随机分为对照组和试验组,每组15头。对照组在产犊前后进行常规饲喂,不喂任何含钙添加剂;试验组在产犊后0h和12h分别投喂一颗缓释钙弹丸。所有试验奶牛分别在产前6h、产犊0h、产后1h、产后13h采集血样、尿样,检测其中钙离子、碱性磷酸酶及其他生化指标的浓度。结果表明,与对照组相比,在两次投喂缓释钙弹丸后各1h(即产后1h及13h),奶牛血钙离子浓度分别提高16.8%和21.1%(P0.05),尿钙离子浓度分别提高77.0%和168.2%(P0.01),但其他血液生化指标如碱性磷酸酶、血糖等无显著变化(P0.05),表明博威钙具有显著提高奶牛血钙离子浓度和尿钙离子浓度的功效。同时,投喂博威钙趋于降低大群奶牛胎衣不下及真胃移位的发生率。 相似文献
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奶牛产后子宫及卵巢超声影像学变化规律的研究 总被引：3，自引：0，他引：3
应用Ｂ－型实时超声断层扫描和放免技术监测产后奶牛子宫和卵巢构相以及外周血浆中雌激素，孕酮和前列腺素Ｆ２ａ代谢物含量的变化，结果表明，应用Ｂ－超可监测到子宫各部分和卵巢的细微复旧变化，并可根据子宫超声影像变化特点判定体内雌激素和孕酮的消长。子宫孕角，空角和子宫颈完成复旧的平均时间分别为４１．０±８．８，３０．６±３．０和４６．７±３．９天。子宫复旧速度不受前妊娠黄体退化时间早晚和外周血浆中ＰＧＦＭ含 相似文献