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Melendez P Goff JP Risco CA Archbald LF Littell R Donovan GA 《Research in veterinary science》2007,82(3):349-357
The objective of this study was to determine the effect of a monensin controlled-release capsule administered intraruminally at drying-off on body condition score (BCS) at calving, milk yield, fertility and concentration of energy-related blood metabolites in Holstein cows dried-off with low BCS (< or = 3.0, scale 1 to 5 with a 0.25 point of increment). Between July and August, 2001, 220 cows from parity 2 or more and dried-off 50-70 days before expected parturition, with a BCS < or = 3.0 were randomly assigned to either a treatment group (n=110; oral capsule of monensin releasing 335 mg/day for 95 days) or a control group (no capsule, n=110). At assignment, on day 21 before expected parturition, at calving, and at 7, 14, and 21 days in milk a blood sample was obtained from a random sub sample of 10 cows per group. Effects of monensin on serum NEFA, BHBA and glucose were measured. Milk yield, milk fat and protein content (%) at DHIA test days during the entire lactation, 305 ME milk production and reproductive responses were compared. Monensin significantly improved BCS at calving, increased milk yield at test days 4 and 8, decreased the percentage of milk protein, did not change the percentage of milk fat, and decreased NEFA and BHBA during the post-partum period. 相似文献
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E R Soto-Belloso L F Archbald R Zemjanis 《American journal of veterinary research》1976,37(9):1103-1105
Monolayers of bovine fetal endometrial cells were established as primary culture cells within 1 to 2 weeks. After the 2nd passage, these cells were inoculated with bovine viral diarrhea virus. Effects of the virus were observed each day with a light microscope. Specific cytopathic effects consisting of degeneration and sloughing of the cells and a well-defined pattern of cytoplasmic vacuolation were observed at 5 days after inoculation. 相似文献
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M L Potter R E Corstvet C R Looney R W Fulton L F Archbald R A Godke 《American journal of veterinary research》1984,45(9):1778-1780
Bovine embryos were exposed to bovine viral diarrhea (BVD) virus in vitro. An uptake of BVD virus by the embryos could not be detected by several assay systems. A significant decrease in the titer of BVD virus was found to occur when the virus was incubated in saline solution + 5% goat serum or minimal essential medium + 5% goat serum for 24 hours at 37 C. Since there was significant inactivation of the BVD virus during the incubation period, lack of viral infectivity of the embryos may have been due to adverse effects of the experimental environmental conditions on the virus or the embryos or upon viral-embryo interaction. 相似文献
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F. K. Al-Bagdadi L. P. Ruhr L. F. Archbald C. W. Titkemeyer C. S. Foil 《Anatomia, histologia, embryologia》1988,17(4):349-359
Eight healthy dogs of mixed breeds with short hair coats were used in this study. The skin and the hair of a small area on the left side of the saddle region were dyed 80 times once every day with a permanent hair dye, Clairol Hair Dye Flaxen Blonde. The dyed regions were red and dry toward the last two weeks of the experiment. None of the dogs had abnormal hair shedding. Four of the dogs were restless, and their epidermis were parakeratotic and hyperkeratotic.
The cuticular cells of the hair shafts of two dogs upon examination showed deep fractures at the lower part of the hair shaft. The fractures extended through the whole thickness of the cuticular cells leading to splitting of the hair shaft. Secondary hairs showed excessive peeling of their cuticle cells causing distortion and deterioration of the cortex of the hair. Cuticular cells of large numbers of hairs lost their apical parts and some of them were deformed due to partial dissolution attributed to the intensive use of the hair dye. The intensive usage of the hair dye on the compound type of hair coat of the dog caused damage to the hair shafts and to the skin in the form of irritation, dryness and parakeratosis of the epidermis. Also, some of the dogs became restless and hyperactive during the later part of the experiment. 相似文献
The cuticular cells of the hair shafts of two dogs upon examination showed deep fractures at the lower part of the hair shaft. The fractures extended through the whole thickness of the cuticular cells leading to splitting of the hair shaft. Secondary hairs showed excessive peeling of their cuticle cells causing distortion and deterioration of the cortex of the hair. Cuticular cells of large numbers of hairs lost their apical parts and some of them were deformed due to partial dissolution attributed to the intensive use of the hair dye. The intensive usage of the hair dye on the compound type of hair coat of the dog caused damage to the hair shafts and to the skin in the form of irritation, dryness and parakeratosis of the epidermis. Also, some of the dogs became restless and hyperactive during the later part of the experiment. 相似文献
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Melendez P Goff JP Risco CA Archbald LF Littell RC Donovan GA 《American journal of veterinary research》2006,67(3):537-543
OBJECTIVE: To determine the effect of a controlled-release monensin capsule administered at cessation of lactation on incidence of calving-related disorders, fertility, and milk yield in dairy cows. ANIMALS: 290 dairy cows treated with monensin and 290 untreated control cows. PROCEDURE: Treated cows received a capsule that released monensin at 335 mg/d for 95 days. Incidence of calving-related disorders; daily milk yield up to 20 days postpartum; test-day milk yield, fat, protein, and mature-equivalent 305-day milk production; and body condition score at calving were determined. Reproductive variables were conception rate at first service, pregnancy rate, and calving-to-conception interval. RESULTS: Cows treated with monensin were 2.1 times as likely to develop dystocia and 0.8 times as likely to develop metritis as control cows. For milk yield, there was an interaction of treatment X time X parity. In multiparous cows, monensin significantly improved milk yield at test days 4 and 7. In addition, monensin increased body condition score at calving. CONCLUSIONS AND CLINICAL RELEVANCE: Despite increasing the likelihood of developing dystocia and metritis, administration of monensin improved the lactational performance of multiparous cows and may be a promising additive for use at the time of cessation of lactation. 相似文献
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The objective was to determine factors influencing social organization in postpartum Angus cows and its effect on variation of cow–calf weight after 90 d. Postpartum Angus cows (N=90) with no history of puerperal problems, a calf suckling, and body condition score (BCS) no less than 3 were allocated into 3 groups of 30 (A, B, and C) according to parity (P) and cow body frame (CF). Using the agonistic interactions recorded during the study, a raw dominance value with subsequent Arc-sin conversion (Arc-sin DV) was calculated to generate a linear social dominance order (DO) with 3 social categories (dominant—D-, intermediate—I-, and subordinate—S-cows). The effects of postpartum body weight (PPBW), BCS, CF, and P on Arc-sin DV were statistically analyzed using ANOVA. Similar procedure was applied to analyze the effects of group, P, CF, and DO on cow body weight at 90 d (CW90), and the effects of DO of dams, P, group, calf gender (CG), and sire within breed (SWB) on calf body weight at 90 d (CFW90). Cows with larger CF and heavier PPBW obtained greatest (P<0.0005) Arc-sin DV. The youngest and the oldest cows tended (P<0.10) to obtain the lowest Arc-sin DV. After 90 d of trial, D cows were heavier than I (P<0.002) and S cows (P<0.0001). Calf birth weight was influenced by SWB (P<0.03) and P (P<0.05), and D cows had heavier (P<0.05) calf at birth than S cows. At 90 d, calf body weight was influenced by P (P<0.03) and DO of dam (P<0.008). Thus, calf weight at 90 d increased with DO of dams. In conclusion, CF, PPBW, and to a less extent P, influenced DO. Parity and CF influenced PPBW. Variation of CW90 was influenced by DO. Calf birth weight was influenced by SWB, P, DO of cow, and CG. Meanwhile, CFW90 was influenced by P and DO of cow. Interactions among social organization, management strategies, calf growth, and reproductive aspects need more attention. 相似文献
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Immunoglobulin concentrations (IgG, IgM, and IgA) in bovine serum, follicular fluid, and uterine and vaginal secretions were determined. The specificities of IgG, IgM, and IgA for virus-neutralizing antibody against bovine viral diarrhea (BVD) and infectious bovine rhinotracheitis (IBR) viruses were also examined. High concentrations of IgG were present in both serum and follicular fluid. The IgG, IgM, and IgA concentrations were low in uterine and vaginal secretions. There was more IgG in the uterus during estrus than at any other time. Virus-neutralizing antibodies against BVD and IBR in serum of cows were mainly the IgG class. There was positive correlation between serum and follicular fluid virus-neutralizing antibody titers fro BVD and IBR. These antibodies may provide some protection for recently ovulated ova. 相似文献