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1.
J Anim Sci ; 99(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34468760

RESUMO

The main objective of this study was to evaluate the effect of peripartal administration of a commercially available nonspecific immune stimulant (mycobacterium cell wall fraction; MCWF [Amplimune, NovaVive Inc., Napanee, ON, Canada]) on the incidence of disease during early lactation and subsequent fertility of dairy cows. A second objective was to characterize the dynamics of circulating white blood cells (WBC) and metabolic markers following treatment administration. Cows in an United States Department of Agriculture (USDA) organic-certified dairy herd were blocked by parity and, based on sequential calving dates, randomly assigned to receive two injections (5 mL s.c.) of either a placebo (saline solution) as a control (CON; n = 71) or MCWF (n = 65) at enrollment (7 d before expected calving) and within 24 h after calving. Blood samples were collected from a subsample of the study population (MCWF = 16; CON = 18) for WBC count at enrollment, at day 2 post enrollment, and at days 1, 3, 7, and 14 after calving. Serum fatty acids, beta-hydroxybutyrate, and Ca concentrations were determined at days 1 and 7 postpartum (MCWF = 21; CON = 21). Main outcome variables included incidence risk of peripartal and early lactation health disorders and pregnancy at first artificial insemination (AI), at 100, and at 150 days in milk (DIM). In addition, the average daily milk yield up to 90 DIM and death and live culling before 305 DIM were compared. Treatment effects were assessed using multivariable logistic regression, time-to-event analyses, and repeated measures analysis of variance (ANOVA). A treatment effect on the incidence risk of some of the health disorders in the study was established. Incidence risk of metritis and clinical mastitis <28 DIM was smaller in MCWF than in CON cows (36.9% vs. 50.7% and 6.3% vs. 19.7%, respectively). On the contrary, the incidence risk of respiratory disease <28 DIM was smaller in CON (0%) than in MCWF (7.7%). Reproductive performance of multiparous cows was affected by MCWF administration: pregnancy at first AI and pregnancy at 100 and 150 DIM were greater in MCWF than in CON (35.6% vs. 19.2%; 51.1% vs. 25.0%; and 64.4% vs. 40.4%, respectively). Overall, median intervals from calving to pregnancy were 90 vs. 121 d in MCWF and CON cows, respectively. No treatment effects on the dynamics of circulating WBC or in postpartum metabolic status were established. No differences for milk yield or for the proportion of cows that survived up to 305 DIM were determined, although cows in MCWF left the herd earlier than cows in CON. In conclusion, incidence risks of metritis and mastitis in early lactation were smaller in cows receiving MCWF, whereas the incidence risk of respiratory disease was smaller in CON. Fertility significantly improved in MCWF compared with CON cows. As this study was performed in an organic-certified dairy, specific health and reproductive management practices may affect the external validity of the current findings.


Assuntos
Doenças dos Bovinos , Mycobacterium , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Parede Celular , Feminino , Fertilidade , Lactação , Leite , Período Pós-Parto , Gravidez , Reprodução
2.
Front Vet Sci ; 7: 550202, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33173793

RESUMO

Our objective was to evaluate the effects of a non-specific immune stimulant (IS) administered around transportation on health scores (HS), average daily gain (ADG), disease treatment and mortality of Jersey and Jersey-cross calves during the rearing period. Newborn calves (4 d ± 1) were randomly allocated to receive either 1 mL of saline (CON; n = 438), 1 mL of IS before transport (BTIS; n = 431), or 1 mL of IS immediately after transport (ATIS; n = 436). Calves were health scored weekly for 3 weeks after transport. The data were analyzed using multivariable linear mixed models and multivariable logistic regression models. Kaplan-Meier survival analysis was performed for time to event analysis. Treatment, birth weight, breed, site of birth, serum total solids, dam parity, season of enrollment, and metaphylaxis were offered to models. Differences in respiratory and fecal HS, and ADG between treatment groups were not statistically significant. A total of 196 (15.0%) calves were treated at least once for any disease and 52 calves were treated multiple times. The proportion of calves treated for respiratory disease and/or diarrhea were 14.4, 14.4, and 16.2% for BTIS, ATIS and CON groups, respectively. Although the differences in the likelihood of treatment for both respiratory disease and/or diarrhea during the first 9 weeks of life was not statistically different between groups, we observed that more calves in the control group received disease treatments around 15 days of age compared with calves that received IS. The likelihood of treatment for respiratory diseases alone during the first 30 days of life was smaller in the calves that received IS before transportation when compared to the control group. Only 18 (1.4%) calves died within the study period. The calf mortality likelihood was not statistically different between study groups; however, fewer calves in the IS groups died when compared to CON. In conclusion, the use of IS around transportation did not influence weekly HS, ADG, and the number of disease treatments during the rearing period, but administering IS before transportation resulted in fewer treatments of respiratory diseases during the first 30 days post-transport and marginally lower mortality rates during the rearing period.

3.
J Dairy Sci ; 103(5): 4302-4314, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32113769

RESUMO

Incidence of subclinical hypocalcemia in early postpartum dairy cows continues to be an animal welfare concern and an economic burden for producers. Feeding prepartum negative dietary cation-anion difference (DCAD) diets produces metabolic acidosis, which supports mobilization of bone calcium and reduces the incidence of hypocalcemia. Achieving a sufficient degree of metabolic acidosis without reducing dry matter intake (DMI) can be difficult. This study compared the ability of MegAnion (MA; Origination O2D Inc., Maplewood, MN), a new DCAD supplement designed to be more palatable than typical anionic salt sources, and another palatable commercial DCAD product, SoyChlor (SC; Landus Cooperative, Ralston, IA), to reduce urine pH (a surrogate for metabolic acidosis) without reducing prepartum DMI. A secondary objective was to assess the effect of these anionic supplements on postpartum serum calcium concentrations and DMI. Prepartum multiparous Holstein (HO) and crossbred (XX) cows were blocked by breed and expected calving date and randomly assigned within breed to total mixed rations (TMR) with MA or SC and DCAD values of -215 mEq/kg of DM. Cows (n = 56; 15 MA-HO, 12 SC-HO, 15 MA-XX, 14 SC-XX) consumed the treatment TMR for at least 19 d and completed the 28 d in milk (DIM) phase of the study. Urine and blood samples were collected weekly and at 1, 2, and 3 DIM. Data were analyzed as a randomized block design by repeated measures with week or DIM as the repeated effect. Prepartum urine pH decreased from 8.15 ± 0.27 before treatment to 6.12 ± 0.14 during treatment, was not affected by anionic supplement, and increased immediately after calving when all cows consumed the same early-lactation TMR. Prepartum serum calcium concentrations were not affected (2.34 vs. 2.33 ± 0.02 mmol/L) by treatment, whereas nonesterified fatty acids were lower (86 vs. 120 ± 10 mmol/L) and insulin was greater (215 vs. 174 ± 10 pmol/L) in cows fed MA than in cows fed SC. These differences are supported by the numerically greater prepartum DMI (1.2 kg/d) and energy balance (1.8 Mcal/d) of cows fed MA. However, pre- and postpartum DMI and other production variables, including body weight, body condition score, milk yield, and energy balance, were not affected by treatment. This lack of difference indicates that MA provides another effective source of anionic salts for diets designed to reduce urine pH and induce metabolic acidosis in prepartum dairy cows.


Assuntos
Ração Animal/análise , Ânions/metabolismo , Cálcio/sangue , Bovinos/fisiologia , Ingestão de Alimentos , Lactação , Animais , Ânions/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Paridade , Distribuição Aleatória
4.
J Vet Pharmacol Ther ; 42(6): 640-646, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31435966

RESUMO

Pharmacokinetic (PK) studies of oral firocoxib in large animal species have been limited to horses, preruminating calves, and adult camels. The aim of this study was to describe pharmacokinetics and bioavailability of firocoxib in adult goats. Ten healthy adult goats were administered 0.5 mg/kg firocoxib intravenously (i.v.) and per os (p.o.) in a randomized, crossover study. Plasma firocoxib concentrations were measured over a 96-hr period for each treatment using HPLC and mass spectrometry, and PK analysis was performed. The p.o. formulation reached mean peak plasma concentration of 139 ng/ml (range: 87-196 ng/ml) in 0.77 hr (0.25-2.00 hr), and half-life was 21.51 hr (10.21-48.32 hr). Mean bioavailability was 71% (51%-82%), indicative of adequate gastrointestinal absorption of firocoxib. There were no negative effects observed in any animal, and all blood work values remained within or very near reference range at the study's conclusion. Results indicate that oral firocoxib is well-absorbed and rapidly reaches peak plasma concentrations, although the concentration also decreased quickly prior to the terminal phase. The prolonged half-life may suggest tissue accumulation and higher plasma concentrations over time, depending on dosing schedule. Further studies to determine tissue residue depletion, pharmacodynamics, and therapeutic concentrations of firocoxib in goats are necessary.


Assuntos
4-Butirolactona/análogos & derivados , Anti-Inflamatórios não Esteroides/farmacocinética , Cabras/sangue , Sulfonas/farmacocinética , 4-Butirolactona/sangue , 4-Butirolactona/metabolismo , 4-Butirolactona/farmacocinética , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/sangue , Área Sob a Curva , Estudos Cross-Over , Feminino , Cabras/metabolismo , Meia-Vida , Sulfonas/sangue , Sulfonas/metabolismo
5.
Vet Clin North Am Food Anim Pract ; 34(1): 83-99, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29203192

RESUMO

Displaced abomasum (DA) is a postpartum disease that causes significant economic losses in the dairy industry. Abomasal atony and excessive production of gas have been reported as prerequisites for the development of DA. The exact cause of DA is unknown, yet infectious and metabolic disease, diet composition and physical form, cow comfort, and management of dairy cows during the transition period have been associated with the occurrence of this disorder. This review article discusses different factors that lead to the development of DA and strategies for monitoring DA and its comorbidities at the herd level.


Assuntos
Abomaso/patologia , Doenças dos Bovinos/patologia , Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios/métodos , Gastropatias/veterinária , Animais , Bovinos , Feminino , Gastropatias/prevenção & controle
6.
Am J Physiol Regul Integr Comp Physiol ; 313(5): R526-R534, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28794103

RESUMO

Modern dairy cows meet the energy demand of early lactation by calling on hormonally driven mechanisms to increase the use of lipid reserves. In this context, we recently reported that fibroblast growth factor-21 (FGF21), a hormone required for efficient use of lipid reserves in rodents, is upregulated in periparturient dairy cows. Increased plasma FGF21 in early lactation coincides with elevated circulating concentrations of glucagon (GCG) and nonesterified fatty acids (NEFA). To assess the relative contribution of these factors in regulating FGF21, two experiments were performed in energy-sufficient, nonpregnant, nonlactating dairy cows. In the first study, cows were injected with saline or GCG every 8 h over a 72-h period. GCG increased hepatic FGF21 mRNA by an average of fivefold over matched controls but had no effect on plasma FGF21. In the second study, cows were infused and injected with saline, infused with Intralipid and injected with saline, or infused with Intralipid and injected with GCG. Infusions and injections were administered intravenously over 16 h and subcutaneously every 8 h, respectively. Intralipid infusion increased plasma NEFA from 92 to 550 µM within 3 h and increased plasma FGF21 from 1.3 to >11 ng/ml 6 h later; FGF21 mRNA increased by 34-fold in liver but remained invariant in adipose tissue. GCG injections during the Intralipid infusion had no additional effects on plasma NEFA, liver FGF21 mRNA, or plasma FGF21. These data implicate plasma NEFA as a key factor triggering hepatic production and increased circulating concentrations of FGF21 in early lactation.


Assuntos
Tecido Adiposo/metabolismo , Ácidos Graxos não Esterificados/sangue , Fatores de Crescimento de Fibroblastos/metabolismo , Glucagon/metabolismo , Fígado/metabolismo , Animais , Bovinos , Feminino , Glucagon/farmacologia , Lactação/fisiologia , Fígado/efeitos dos fármacos , RNA Mensageiro/genética , Regulação para Cima
7.
FEMS Microbiol Ecol ; 79(2): 518-29, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22093037

RESUMO

Papillomatous digital dermatitis (PDD) is one of the most prevalent diseases of cattle, adversely affecting the dairy industry by its negative effect on milk production and reproductive performance. Our objective was to use culture-independent methods to determine the microbial diversity in different strata of PDD lesions of three Holstein dairy cows, analyzing whether major differences exist compared to foot skin of three non-infected cows. Both group-specific 16S rRNA gene PCR-denaturing gradient gel electrophoresis and clone library sequencing of broad-range 16S rRNA gene showed differences between the microbial composition of healthy dairy cows and the different strata of the lesion. The predominant bacterial community in the lesion, regardless of the stratum, consisted of 166 specific phylotypes belonging to seven bacterial phyla. Spirochetes (particularly, treponemes) was the most prominent group detected in PDD deep biopsies and was only found in samples from the lesion. Additionally, one phylotype phylogenetically affiliated with uncultured Euryarchaeota was detected in two strata of the lesion. Sequences from healthy foot skin samples revealed 86 specific phylotypes that were affiliated with Firmicutes and Proteobacteria. Our study corroborates the theory that treponemes are involved in PDD disease etiology and suggests, for the first time, the presence of archaeal members in this particular bovine infection.


Assuntos
Bactérias/classificação , Doenças dos Bovinos/microbiologia , Dermatite Digital/microbiologia , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Sequência de Bases , Biodiversidade , Bovinos , Feminino , Dados de Sequência Molecular , New York , Reação em Cadeia da Polimerase , Spirochaetales/classificação , Spirochaetales/genética , Spirochaetales/isolamento & purificação , Infecções por Spirochaetales/veterinária , Treponema/classificação , Treponema/genética , Treponema/crescimento & desenvolvimento
8.
Am J Vet Res ; 72(10): 1338-43, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21962276

RESUMO

OBJECTIVE: To develop a parsimonious statistical model to predict incidence of lameness in the subsequent lactation by use of data collected at cessation of lactation in dairy cows. ANIMALS: 574 cows. PROCEDURES: At cessation of lactation during hoof trimming, body condition score (BCS), visual locomotion score, digital cushion thickness (DCT), and digital lesions were assessed. RESULTS: 140 (24%) cows were treated for claw horn disruption lesions (CHDLs) at cessation of lactation (114 with sole ulcers [pododermatitis circumscripta] and 26 with white line disease). The BCS was highly associated with DCT. Cows with CHDLs at cessation of lactation had significantly lower DCT, compared with other cows. All 3 logistic regression models predicted the incidence of CHDLs in the subsequent lactation with good accuracy; the area under the receiver operating characteristic curves was 0.76, 0.76, and 0.77 for the first, second, and third logistic regression models, respectively. CONCLUSION AND CLINICAL RELEVANCE: Evaluation of 3 logistic regression models indicated that lameness could be predicted with good accuracy by use of all 3. The ability to predict lameness will facilitate the implementation of lameness prevention strategies by targeting specific cows.


Assuntos
Doenças dos Bovinos/diagnóstico , Indústria de Laticínios , Doenças do Pé/veterinária , Casco e Garras/patologia , Lactação/fisiologia , Coxeadura Animal/diagnóstico , Animais , Constituição Corporal , Bovinos , Feminino , Doenças do Pé/diagnóstico , Doenças do Pé/patologia , Modelos Logísticos , Modelos Estatísticos
9.
Am J Vet Res ; 72(8): 1079-86, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21801066

RESUMO

OBJECTIVE: To isolate and characterize bacteriophages with strong in vitro lytic activity against various pathogenic Pseudomonas aeruginosa strains isolated from dogs with ocular infections. SAMPLE: 26 genetically distinct P aeruginosa isolates. PROCEDURES: P aeruginosa strains were derived from dogs with naturally acquired ulcerative keratitis. From a large-scale screening for bacteriophages with potential therapeutic benefit against canine ocular infections, 2 bacteriophages (P2S2 and P5U5) were selected; host ranges were determined, and phage nucleic acid type and genetic profile were identified via enzymatic digestion. Electron microscopy was used to characterize bacteriophage ultrastructure. Bacteriophage temperature and pH stabilities were assessed by use of double-layer agar overlay titration. A cocultivation assay was used to evaluate the effect of the bacteriophages on bacterial host growth. RESULTS: P5U5 was active against all P aeruginosa isolates, whereas P2S2 formed lytic plaques on plates of 21 (80.8%) isolates. For each bacteriophage, the genomic nucleic acid was DNA; each was genetically distinct. Ultrastructurally, P2S2 and P5U5 appeared likely to belong to the Podoviridae and Siphoviridae families, respectively. The bacteriophages were stable within a pH range of 4 to 12; however, titers of both bacteriophages decreased following heating for 10 to 50 minutes at 45° or 60°C. Growth of each P aeruginosa isolate was significantly inhibited in coculture with P2S2 or P5U5; the dose response was related to the plaque-forming unit-to-CFU ratios. CONCLUSIONS AND CLINICAL RELEVANCE: Bacteriophages P2S2 and P5U5 appear to be good candidates for phage treatment of infection caused by pathogenic P aeruginosa in dogs.


Assuntos
Bacteriófagos/isolamento & purificação , Úlcera da Córnea/veterinária , Doenças do Cão/prevenção & controle , Infecções Oculares/veterinária , Infecções por Pseudomonas/veterinária , Pseudomonas aeruginosa/virologia , Animais , Tipagem de Bacteriófagos , Bacteriófagos/genética , Bacteriófagos/crescimento & desenvolvimento , Bacteriófagos/ultraestrutura , Úlcera da Córnea/microbiologia , Úlcera da Córnea/prevenção & controle , DNA Viral/análise , Doenças do Cão/microbiologia , Cães , Infecções Oculares/microbiologia , Infecções Oculares/prevenção & controle , Variação Genética , Especificidade de Hospedeiro , Podoviridae/genética , Podoviridae/crescimento & desenvolvimento , Podoviridae/isolamento & purificação , Podoviridae/ultraestrutura , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Siphoviridae/genética , Siphoviridae/crescimento & desenvolvimento , Siphoviridae/isolamento & purificação , Siphoviridae/ultraestrutura
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