RESUMEN
Artificial insemination (AI) with liquid-preserved stallion semen is a widely used reproductive technology. As the demand for AI doses of high-class stallions is transnational, they are frequently exposed to long-distance transport. Since recent studies in boars indicated that vibration emissions caused by transport negatively affected sperm quality in vitro, this study questioned whether sperm quality in stallions is similarly impaired. Furthermore, we investigated stallion and extender-related differences in the spermatozoa's resistance to transport-related quality loss. Stallion ejaculates (n = 30) were collected at a German AI center, split in half, and subsequently diluted to a final sperm concentration of 50 × 106 sperm/mL using the semen extenders EquiPlus or Gent (both Minitüb GmbH, Germany). Four 12 mL aliquots of each sample were filled in plastic syringes according to a split-sample design and exposed to vibration (Displacement index Di = 3.0 ± 0.1) at 5 °C for 0 h (control), 3 h, 6 h or 9 h. All samples were stored for four days at 5 °C after transport simulation and analyzed for total sperm motility, thermo-resistance, membrane integrity, and mitochondrial activity determined by flow cytometry as well as the pH. After calculating generalized linear mixed models for each sperm quality trait, a negative impact of the duration of transport simulation could be shown on total sperm motility (P = 0.001), thermo-resistance (P = 0.030), and the pH (P = 0.001). Simulated transport for 6 h and 9 h diminished sperm quality (P ≤ 0.01), with 9 h reducing thermo-resistance by 5 ± 2.2% points (PP) for EquiPlus and sperm motility by 2.2 ± 1.7 PP for Gent compared to the control group. In contrast, samples exposed to vibration for 3 h showed no decline in sperm quality (P > 0.05). The individual stallion influenced every semen trait (P < 0.05) and transport-related losses in sperm thermo-resistance of up to 15.9 PP were demonstrated. Furthermore, EquiPlus was superior to Gent in all semen assessments (P < 0.001). We conclude that in vitro sperm quality is impaired by vibration. As the quality loss depends on the transport time, we recommend keeping shipping time as short as possible especially for spermatozoa of stallions that are susceptible to vibration-induced sperm quality loss.
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Preservación de Semen , Semen , Caballos , Masculino , Animales , Porcinos , Motilidad Espermática , Preservación de Semen/veterinaria , Vibración , Espermatozoides , Inseminación Artificial/veterinariaRESUMEN
External factors can affect reproductive traits of breeding boars and especially the sensitive process of spermatogenesis. The aim of this study was to investigate probable influences of bedding materials (chipsy wood shavings (CWS), hemp straw (HS), linen straw (LS), spelt husks (SH), and regional wood shavings (RWS)) on semen traits of 40 randomly selected Piétrain boars (8 boars per group, age: 2.35 ± 1.23 years). After a six-week adaptation period, 40 fresh semen samples were collected weekly for four weeks and diluted in BTS (4 consecutive ejaculates per boar, 32 samples per group, 160 samples in total). Semen samples were analyzed using an extended range of spermatological methods (e.g., computer-assisted sperm analysis and flow cytometry). Generalized linear mixed models for each sperm parameter as well as the area under the curve for total sperm motility and thermo-resistance test were calculated. Materials LS and SH exceeded the standard maximum level for pesticide residues (VO (EG) No. 396/2005). Materials HS and LS presented the highest water-binding capacity of 413 % and 357 %, respectively, while SH showed the lowest value of 250 %. There were no significant (P > 0.05) differences between groups in any sperm characteristic, therefore indicating that bedding material had no influence on sperm quality. For most semen traits, however, we found significant (P ≤ 0.001) differences between sampling weeks. Based on pesticide results, we suggest CWS, RWS, or HS as possible bedding materials for pig production farms in the future. Furthermore, we strongly recommend a quality analysis of any new bedding material before use in swine husbandry.
Asunto(s)
Semen , Motilidad Espermática , Animales , Masculino , Porcinos , Espermatozoides , Análisis de Semen/veterinaria , ReproducciónRESUMEN
Artificial insemination (AI) centers' economic profitability is directly impacted by the amount of high-quality sperm doses. Many internal and external factors contribute to the quality of ejaculates. To enhance the libido and to reduce the time that is required to train boars for semen collection, prostaglandin products are used routinely at AI centers. The objectives of this study were to analyze sperm parameters of 40,765 ejaculates and the survival of 406 PGF2α-treated and 417 untreated AI boars of five breeds (Duroc [DU], Large White [LW], Landrace [LR], Pietrain [PI], and Large White Sire Line [LS]). Data were assessed in one AI center in Switzerland from 2018 to 2022 and sperm parameters were determined by computer-assisted sperm analysis immediately after semen collection. For further calculations, the ejaculates were divided into four groups depending on the boar's age at semen collection day: 7 to 11, 12 to 18, 19 to 24, and 25 to 87 mo. Along with the boar age, breed, season, and semen collection frequency even the treatment with PGF2α had significant influence on sperm parameters. Overall, 19.5% ejaculates were collected after PGF2α treatment. For every age and breed group, higher ejaculate volume was found for untreated boars than for PGF2α-treated boars (Pâ <â 0.001). Higher values for total and progressive sperm motility, total sperm number, and the proportion of morphologically normal sperm were observed in untreated boars across several age and breed groups. Only for sperm concentration, higher values were found for treated boars older than 11 mo (Pâ <â 0.001) and the breeds DU, LW, and LR (Pâ <â 0.001). The chance of ejaculates being rejected for AI purposes because of low sperm quality was 21% greater for treated boars. There was no difference in survival between treated and untreated boars. The hazard for boar removal increased with decreasing age at first semen collection and decreasing semen collection frequency. The results reveal better sperm quality for untreated boars than for PGF2α-treated boars, which might indicate that the underlying fertility of boars necessitating treatment is inferior compared to boars that can be collected without further treatment. Therefore, AI boar stations that are aiming to reduce PGF2α treatment should pay special attention to high libido and fertility of young prospective AI boars.
In many artificial insemination (AI) centers, prostaglandin products are used routinely to enhance the mounting behavior of boars with libido problems and to expedite the training of young boars to mount an artificial sow and allow semen collection. Recent studies examining the influence of prostaglandin-F2α (PGF2α) on sperm quality are still rare and present low sample sizes and diverse results. The aim of this study was to analyze AI center management factors that affect boar longevity and sperm parameters with a main focus on PGF2α treatment. The analysis compares sperm parameters of 40,765 ejaculates and the longevity of 823 PGF2α-treated and untreated AI boars based on 4 yr of data. Sperm parameters were assembled by computer-assisted sperm analysis. The results revealed that not only boar age, breed, semen collection technician, season, and the monthly collection frequency contributed significantly to the sperm parameters, but also the treatment with PGF2α. While we found at least greater values for ejaculate volume, total sperm number, and total and progressive motility for untreated boars, the longevity at AI center was not affected by PGF2α treatment. Rather, the boar's age at first semen collection session and the semen collection frequency had significant influence on the survival time of AI boars.
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Dinoprost , Semen , Porcinos , Masculino , Animales , Dinoprost/farmacología , Longevidad , Estudios Prospectivos , Motilidad Espermática , Espermatozoides , Análisis de Semen/veterinaria , Inseminación Artificial/veterinaria , Inseminación Artificial/métodosRESUMEN
While studies have been conducted examining the stress response of dairy cattle to individual acute and chronic stressors, the results are difficult to compare due to differences in study design and analysis methods. The aim of the present study was to conduct a comparative assessment of the impact of eight common stimuli: artificial insemination (AI), embryo transfer (ET), morning milking (MM), evening milking (EM), veterinary examination (VE), ultrasound examination (US), hoof trimming (HT), and natural breeding (NB) on the hypothalamic-pituitary-adrenal axis and milk production of 24 Holstein-Friesian cattle. After random allocation into control and treatment groups, a total of five blood samples were collected 40 min (Ba1) and 20 min (Ba2) prior to stimulus application, immediately following the stimulus (St), as well as 20 min (Re1) and 40 min (Re2) post-stimulus. A comparison between the overall serum cortisol concentrations in the treatment groups showed a significant difference between HT to AI (p = 0.006), ET (p = 0.010), MM (p = 0.021), VE (p = 0.009), EM (p = 0.007), and US (p = 0.010), except for NB (p = 0.542). There is no significant difference between the control groups (p > 0.05). The stimuli HT (p < 0.001) and NB (p < 0.001) showed significant increases in cortisol following stimulus application, and the levels failed to decrease significantly by sample Re2. No significant differences in daily milk yield (kg) were measured amongst the tested stimuli (p = 0.472) nor amongst the groups 'Control', 'Treatment' and 'no stimulus' (p = 0.350). In conclusion, when factors such as increased physical activity, novel social interaction, sexual arousal, and a more intense restriction of movement are present, the animal's perceived controllability and predictability might decrease, affecting the animal's response to stress. Treatments carried out while animals are restrained in a headlock while remaining within their regular group likely result in a less intense activation of the HPA axis.
RESUMEN
Equilibration with an extender is necessary to allow cryopreservation of bovine sperm. The aim of trial 1 was to assess the effect of 24 h versus 4 h equilibration time with three different extenders on sperm quality and to select the preferred extender for each bull. The aim of trial 2 was to investigate the effect of using a 24 h equilibration time with a bull-specific extender on field fertility. For trial 1, three ejaculates each from eight Holstein Friesian breeding bulls were used as the split-sample, including two equilibration times (4 h and 24 h) and three extenders (BioXcell, Triladyl, and OptiXcell). For trial 2, from 5 to 10 ejaculates from the same bulls were collected and treated (split-sample) as BioXcell with 4 h equilibration and either Triladyl or OptiXcell, both with 24 h equilibration. A total of 11,059 straws were used for insemination of cows and heifers. For Triladyl, progressive sperm motility, acrosome defects, and plasma membrane and acrosome integrity improved with a 24 h compared to a 4 h equilibration time. Four bulls each were used with Triladyl and OptiXcell for trial 2. In trial 2, non-return rates did not differ among groups. Therefore, using a 24 h equilibration time might improve in vitro sperm parameters, depending on the extender used. Moreover, it would be possible to change from 4 h to 24 h equilibration time without impairing field fertility.
RESUMEN
In the face of antimicrobial resistance, antibiotic-free, low-temperature storage of boar semen has been well-researched in recent years and promising results have been obtained. With the prospect of establishing this new preservation method in practice, it is important to evaluate a range of factors, possibly influencing the general and/or boar individual preservation suitability for 5 °C storage. The present study aimed to evaluate the influence of boar age (<18 months (n = 29) vs. 18-36 months (n = 68) vs. >36 months (n = 56)), breed (Pietrain (n = 104) vs. Duroc (n = 49)), as well as the influence of season (summer (n = 73) vs. winter (n = 80)) on the quality of boar semen preserved in antibiotic-free Androstar® Premium extender. AI doses were stored at 5 °C after cooling according to an established cooling protocol. In total, 153 ejaculates were analyzed throughout two identical experimental runs in summer and in winter, and the boars were divided into the corresponding sub-groups based on their age and breed. The application of a general linear model (GLM) and subsequent Bonferroni-corrected post hoc tests did not reveal any significant differences in the quality of semen stored at 5 °C between the different age groups. Regarding the season, a difference was found in the progressive motility (PM) at two out of seven analysis time points (P ≤ 0.01), however, this difference in PM was also present in fresh semen (P < 0.001). Most significant differences were found when comparing the two breeds. At six out of seven analysis time points, PM of Durocs was significantly lower than PM of Pietrains. Again, this difference in PM was also recognizable in fresh semen (P < 0.001). No differences were found in plasma membrane and acrosome integrity examined by flow cytometry. In conclusion, our study confirms the feasibility of 5 °C storage of boar semen under production conditions regardless of boar age. While season and breed have an influence on boar semen stored at 5 °C, these differences are not primarily caused by storage temperature, as they were already apparent in fresh semen.
Asunto(s)
Líquidos Corporales , Semen , Porcinos , Animales , Masculino , Temperatura , Estaciones del Año , Frío , AntibacterianosRESUMEN
Low fertility rates in lactating dairy cows as well as restricted availability of semen doses of young bulls with high genetic merit are two major problems in the reproduction of dairy cows. By using liquid semen (LS), the number of doses per ejaculate can be increased. One of the challenges of optimizing the reproductive performance of dairy cows is the phenomenon of variable estrus lengths. The objective of this study was to determine whether the use of LS affects pregnancy outcome of dairy cows with delayed ovulation, when compared with frozen semen (FS). A randomized controlled clinical trial was implemented. In a split-sample procedure, 131 ejaculates were processed into LS (Caprogen, LIC, New Zealand) and FS (BioXcell, IMV, France). Both semen types of each ejaculate were inseminated under the same field conditions to cows showing natural or induced heat. Cows and semen type were allocated according to the last digit of the cows identification number (even = frozen semen, odd = liquid semen). Inseminations (n = 667) were conducted after localization of the pre-ovulatory follicle. Determination of ovulation was performed 24 h post AI per transrectal ultrasonographic examination. Ovulations were classified as delayed when the pre-ovulatory follicle was still present at ovulation control. The prevalence of delayed ovulations was 25.2%. Data of 667 inseminations were analyzed with a generalized linear mixed model including semen type (P = 0.016), parity (P = 0.014), backfat thickness (P = 0.006), estrus induction (P = 0.010), ovulation (P = 0.265) and the interaction term 'semen type by ovulation' (P = 0.094). Overall, a higher pregnancy per AI (P/AI) of LS (45.4%) than P/AI of FS (33.7%) was found. In cases of delayed ovulations, use of LS resulted in higher P/AI (46.8%) compared with FS (27.7%; P = 0.017). We concluded that the fertilizing capacity of LS in prolonged intervals from AI to ovulation might be greater when compared with FS and could be an efficient tool to improve fertility of lactating dairy cows with delayed ovulations.
Asunto(s)
Lactancia , Semen , Femenino , Embarazo , Bovinos , Animales , Masculino , Inseminación Artificial/veterinaria , Inseminación Artificial/métodos , Fertilidad , Resultado del Embarazo , Ovulación , Sincronización del Estro , Hormona Liberadora de Gonadotropina/farmacología , Progesterona/farmacologíaRESUMEN
BACKGROUND: Digital flexor tendon sheath (DFTS) pathology is an important cause of lameness in horses. The outcome after surgical treatment is variable and depends on the exact diagnosis. OBJECTIVES: To (1) describe the prevalence of lesions associated with lameness caused by nonseptic DFTS tenosynovitis in a large population of German sports and pleasure horses; (2) determine the sensitivity and specificity of diagnostic imaging techniques for identifying lesions within the DFTS with tenoscopic diagnosis being the gold standard; (3) explore associations between tenoscopically diagnosed lesions and signalment, purpose, and limb affected; and (4) describe the outcome following DFTS tenoscopy with nonseptic DFTS tenosynovitis in this population. STUDY DESIGN: Retrospective case series. METHODS: Medical records of horses admitted for tenoscopic surgery of nonseptic DFTS tenosynovitis between 2011 and 2020 were reviewed. Follow-up information was obtained via telephone contact. Sensitivity and specificity of ultrasonography and contrast tenography were determined using tenoscopic diagnosis as gold standard and univariable analysis was used to explore associations between signalment, case history, and tenoscopic diagnosis. RESULTS: Medical records from 131 horses were retrieved, of which 8 horses had bilateral disease and 6 horses were presented for tenoscopy on two separate occasions (3 for tenoscopy in the same limb, 3 in a different limb), thus, making a total of 145 limbs. Lesions were most commonly diagnosed in the deep (DDFT; n = 55 limbs) and superficial (SDFT; n = 55 limbs) digital flexor tendons. Manica flexoria (MF) lesions were detected in 44 limbs and palmar/plantar annular ligament (PAL) constriction in 99 limbs. In 36 limbs, only one structure within the DFTS was injured, whereas in 109 limbs a combination of lesions was noted, the most common being the combination of a SDFT lesion with PAL constriction. All affected limbs were examined with diagnostic ultrasonography; contrast tenography was performed in 86 limbs. For diagnosis of MF and DDFT tears, tenography was more sensitive (89% [confidence interval, CI: 65.4%-95.2%]; 72% [CI: 46.4%-89.3%], respectively) than specific (64% [CI: 52.5%-77.6%]; 53% [CI: 42.2%-73.3%], respectively) whereas ultrasonography was more specific (92% [CI: 84.5%-96.3%]; 92% [CI: 83.6%-96.0%]) with lower sensitivity (64% [CI: 47.7%-77.2%]; 54% [CI: 39.5%-67.9%]). For SDFT lesions, ultrasonography was highly specific (94% [CI: 86.9%-97.9%]) with lower sensitivity (66% [CI: 51.3%-77.4%]). Follow-up information following first surgery was obtained for 118 horses (132 limbs): 18 (15.3%) of 118 horses remained chronically lame, 40 (33.8%) performed at a reduced level and 60 (50.8%) performed at the same or higher level following rehabilitation after tenoscopy. Horses with DDFT lesions had the poorest outcomes with only 36.6% returning to the same or higher level of exercise. MAIN LIMITATIONS: Retrospective analysis of clinical records and subjective outcome assessment based on owner follow-up with potential recall bias. Findings on diagnostic imaging are impacted by many factors including equipment quality and operator expertise and experience. CONCLUSION: Diagnostic imaging techniques were complimentary and contrast tenography was sensitive and ultrasonography was specific for the diagnosis of MF and DDFT lesions. Following tenoscopic surgery for nonseptic tenosynovitis of the DFTS, approximately half the cases were able to return to preinjury level of exercise.
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Enfermedades de los Caballos , Tenosinovitis , Animales , Miembro Anterior/patología , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Caballos/cirugía , Enfermedades de los Caballos/patología , Caballos , Cojera Animal/diagnóstico , Placer , Estudios Retrospectivos , Tendones/cirugía , Tendones/patología , Tenosinovitis/diagnóstico , Tenosinovitis/cirugía , Tenosinovitis/veterinariaRESUMEN
This research communication describes (1) the comparison of acute-phase protein (APP) concentrations in transition dairy cows on different farms using both pooled and individual blood samples, and (2) the association among different APP and clinical health parameters. The first hypothesis was that early postpartum dairy cows from different farms differ in the level of inflammation, which might be determined using APP assays in both pooled and individual blood samples. The second hypothesis was that the APP haptoglobin (Hp) might be the most sensitive parameter to detect cows at risk of excessive postpartum inflammation concomitant with systemic disease. Serum concentrations of Hp, serum amyloid-A (SAA), total protein (TP), albumin (Alb), coeruloplasmin (Cp) and C-reactive protein (CRP) in 100 fresh lactating cows (within 0-8 d postpartum) from 10 farms were compared and associated to clinical health parameters (rectal body temperature, vaginal discharge (Metricheck™ score), rumen fill, vulvovaginal laceration) using both pooled and individual blood samples. Mean serum concentrations of Hp, SAA and TP revealed significant differences among farms. Pooled serum samples of farms showed high correlations with the mean of individual samples. Only Hp was significantly positively correlated to both body temperature and Metricheck™ score. In conclusion, Hp differentiates dairy farms regarding the inflammatory state of transition cows using individual and pooled serum samples within the first week postpartum. It also mirrors the individual degree of inflammation, thus proving to be a diagnostic parameter of high interest during the periparturient period.
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Proteínas de Fase Aguda/análisis , Enfermedades de los Bovinos/sangre , Periodo Posparto/fisiología , Animales , Proteínas Sanguíneas/análisis , Proteína C-Reactiva/análisis , Bovinos , Enfermedades de los Bovinos/inmunología , Industria Lechera , Femenino , Haptoglobinas/análisis , Inflamación/sangre , Inflamación/veterinaria , Proteína Amiloide A Sérica/análisisRESUMEN
In standing dairy cows, the medial claws carry most of the load of the forelimb. The goal of our experimental study was to investigate how even load distribution can be achieved between the paired forelimb claws through foot trimming. We measured vertical ground reaction forces, mean and maximum pressures, and contact areas under the sound forelimb claws of 28 nonlame dairy cows using a force plate and a pressure plate. The experimental setup consisted of 3 measurement situations: (1) baseline measurements made after routine foot trimming, (2) measurements made with plywood plates, 3 mm in thickness, attached to both lateral claws, and (3) measurements made with the same plywood plates attached to both medial claws. After routine foot trimming, the medial claws carried 70.1% of the entire forelimb load with its palmar zone bearing 54.0% of the entire forelimb load. Even load distribution between the paired claws was achieved when the plywood plates were attached to the lateral claws, whereas plates on the medial claws increased the load discrepancy. The pressures on the medial claws were reduced by attaching the plywood plates to the lateral claws but remained uneven between paired claws and claw zones. The palmar zone of the medial claws was the region subjected to the greatest force and highest pressures in all situations. A drawback of the study was that the plywood plates increased the contact area and therefore reduced the mean and maximum pressures in the claws they were attached to. We concluded that equal load distribution between the forelimb claws was achieved in our setting when the lateral claws were left 3 mm higher than the medial claws.
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Enfermedades de los Bovinos , Enfermedades del Pie , Pezuñas y Garras , Animales , Bovinos , Femenino , Enfermedades del Pie/veterinaria , Miembro Anterior , PresiónRESUMEN
The importance of biosecurity as a strategy to prevent and control infectious diseases has increased substantially over the last few decades. Several studies have reported a low implementation level of biosecurity measures (BSM), particularly in cattle farms. In addition, a recent study demonstrated that cattle farmers are well aware of the recommended BSM and recognize them as more effective (in terms of time and costs) than treatment for disease. Therefore, other factors must be considered when it comes to understanding the decision-making process followed by a farmer regarding the adoption of BSM. This study analysed the possible influence of five mental constructs described in the health belief model (HBM) on the adoption of BSM and assessed the possible association of these constructs with different demographic and socio-psychological factors. Through an online survey, 988 questionnaires were completed by cattle farmers originating from Belgium, France, Germany, Spain and the Netherlands. The study revealed that the actual implementation of the BSM seems to be significantly influenced by the farmers' perception of the measures' benefits and the perception of health responsibility. Both constructs are influenced by the farmers' personality in terms of risk aversion and biosecurity knowledge. It was also found that organic farmers had a significantly lower perception of the BSM benefits and of their responsibility towards animal, public and environmental health when compared with other types of farmer. Organic farmers in this study seemed less likely to implement biosecurity measures. To increase the adoption of BSM by cattle farmers, it is therefore important to emphasise the actual evidence-based benefits of the measures and to investigate further how to strengthen cattle farmers' sense of responsibility towards animal, public and environmental health.
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Enfermedades de los Bovinos , Agricultores , Crianza de Animales Domésticos , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Humanos , Percepción , Proyectos Piloto , Encuestas y CuestionariosRESUMEN
OBJECTIVE: Claw health and carpal and tarsal lesions were assessed in a dairy herd during the transition from a tie-stall to a free-stall barn. The stress associated with the change in housing was also evaluated. MATERIALS AND METHODS: The initial size of the herd was 57 dairy cows, which were evaluated 4 times, 4-5 months apart, in a hoof-trimming chute. Claw horn and skin lesions of the foot were considered separately. The carpi and hocks were assessed for hair loss and skin lesions, and the hocks were also evaluated for swelling. Tail hair samples were collected from all cows during the second visit, and the cortisol concentration of 3 different sections of the hair was measured. RESULTS: The high prevalence of digital dermatitis and other skin lesions in the hind legs seen in the tie-stall barn (49 %) did not change significantly during the 14-month study period and was 46 % at the last visit. Heel horn erosions of the hind feet were rare in the tie-stall barn (14 %), but had a prevalence of 100 % at the end of the study. There was a trend for a decrease in the prevalence of other claw horn lesions. The prevalence and severity of carpal and hock lesions decreased significantly in the free-stall barn. Compared to values in cows at the tie-stall barn, the hair cortisol concentration was significantly higher during the transition period and at the free-stall barn. DISCUSSION AND CONCLUSIONS: The target variables were subjected to a multitude of factors but it can be assumed that the more comfortable lying surface in the free-stall barn had the most significant effect on carpal and tarsal joint health. The fluctuating prevalence of claw horn lesions indicates that claws health should be monitored closely. The increase in hair cortisol concentration after the transition to the free-stall barn could imply increased stress, but washout of cortisol in more distal hair segments could not be ruled out. CLINICAL RELEVANCE: The results of the present report cannot be directly applied to other herds; however, the significance of cow comfort is highlighted by the presence of fewer carpal and hock lesions. The significant increase in the prevalence of heel horn erosions indicates that the horn capsule is compromised under free-stall conditions.
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Bovinos/fisiología , Cabello/química , Pezuñas y Garras , Vivienda para Animales , Hidrocortisona/análisis , Crianza de Animales Domésticos/métodos , Animales , Enfermedades de los Bovinos , Industria Lechera , Granjas , Femenino , Pezuñas y Garras/fisiología , Pezuñas y Garras/fisiopatologíaRESUMEN
Despite a well-documented effect of high dietary zinc oxide on the pig intestinal microbiota composition less is it yet known about changes in microbial functional properties or the effect of organic zinc sources. Forty weaning piglets in four groups were fed diets supplemented with 40 or 110 ppm zinc as zinc oxide, 110 ppm as Zn-Lysinate, or 2500 ppm as zinc oxide. Host zinc homeostasis, intestinal zinc fractions, and ileal nutrient digestibility were determined as main nutritional and physiological factors putatively driving colon microbial ecology. Metagenomic sequencing of colon microbiota revealed only clear differences at genus level for the group receiving 2500 ppm zinc oxide. However, a clear group differentiation according to dietary zinc concentration and source was observed at species level. Functional analysis revealed significant differences in genes related to stress response, mineral, and carbohydrate metabolism. Taxonomic and functional gene differences were accompanied with clear effects in microbial metabolite concentration. Finally, a selection of certain antibiotic resistance genes by dietary zinc was observed. This study sheds further light onto the consequences of concentration and chemical form of dietary zinc on microbial ecology measures and the resistome in the porcine colon.
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Antibacterianos , Zinc , Alimentación Animal/análisis , Animales , Colon , Dieta , Farmacorresistencia Microbiana , Porcinos , DesteteRESUMEN
Gut integrity impairment leading to increased intestinal permeability (IP) is hypothesized to be a trigger of critically illness. Approximately 15-20% of human ischemic stroke (IS) victims require intensive care, including patients with impaired level of consciousness or a high risk for developing life-threatening cerebral edema. Local and systemic inflammatory reactions are a major component of the IS pathophysiology and can significantly aggravate brain tissue damage. Intracerebral inflammatory processes following IS have been well studied. Until now, less is known about systemic inflammatory responses and IS consequences apart from a frequently observed post-IS immunosuppression. Here, we provide a hypothesis of a crosstalk between systemic acute phase response (APR), IP and potential secondary brain damage during acute and subacute IS stages supported by preliminary experimental data. Alterations of the acute phase proteins (APPs) C-reactive protein and lipopolysaccharide-binding protein and serum level changes of antibodies directed against Escherichia coli-cell extract antigen (IgA-, IgM-, and IgG-anti-E. coli) were investigated at 1, 2, and 7 days following IS in ten male sheep. We found an increase of both APPs as well as a decrease of all anti-E. coli antibodies within 48 h following IS. This may indicate an early systemic APR and increased IP, and underlines the importance of the increasingly recognized gut-brain axis and of intestinal antigen release for systemic immune responses in acute and subacute stroke stages.
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OBJECTIVE: The objective of this study was to evaluate the suitability of feces as sample material for the evaluation of trace mineral supply in cattle. Fecal trace element concentrations of iron, copper, zinc, selenium, manganese and molybdenum were compared with those in feed. Furthermore, fecal trace element-concentrations were compared with those in various additional sample media (serum, plasma, whole blood, urine and hair). MATERIALS AND METHODS: Samples (feces, blood, urine, hair) from up to 10 cows in the close-up (3-0 weeks a. p.) and high-yielding (6-20 weeks p. p.) group each were collected during 73 farm visits on 63 dairy farms. Pooled samples of each lactation group were formed and the concentrations of trace elements were determined with ICP-OES or ICP-MS. Furthermore, TMR was analyzed. Additionally, feces from cattle in cow-calf herds during grazing and housing period were evaluated. RESULTS: Nutritional trace mineral requirements were exceeded by the majority of feeds. Trace mineral concentrations were 2- to 3-fold higher in feces than in feed. In this study, the strongest significant correlation existed between feed and fecal concentrations for all elements. Seasonal variations were detected for iron, copper and manganese. Furthermore, iron concentration differed depending on lactation stage. CONCLUSION AND CLINICAL RELEVANCE: Feed intake of the trace minerals analyzed is most optimally reflected by the fecal concentration in comparison to other substrates. Fecal analysis of these minerals may therefore be employed as an alternative to feed analysis with regards to the evaluation of nutritional trace mineral supply. Analyzing fecal trace mineral concentrations possesses practical significance wherever feed or TMR cannot be analyzed. In particular, this concerns grazing animals, heifers, mother cows and cattle in barns without TMR. Assessment of the complete metabolic status only on the basis of fecal contents is insufficient. However, subnormal fecal copper-, zinc- and manganese concentrations may be suggestive of an inadequate metabolic situation and represent an indication for further diagnostics.
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Alimentación Animal/análisis , Heces/química , Oligoelementos/análisis , Animales , Bovinos , Femenino , Cabello/química , Estaciones del Año , Oligoelementos/sangre , Oligoelementos/orinaRESUMEN
Environmental modifications disturb the equilibrium of mosquito populations, altering the risk of mosquito-borne diseases. Mosquito distribution, diversity, and bloodmeal sources were examined to compare Rift Valley fever (RVF) risk among irrigated, riverine, and pastoral ecosystems in Bura, Tana River County, Kenya, between September 2014 and June 2015. Thirty-eight households and 21 irrigation fields were selected for the study. Mosquitoes were trapped with carbon dioxide-impregnated CDC traps, one trap per household and three traps per irrigated field, and morphologically identified using taxonomic keys. Host DNA was extracted from engorged females and cytochrome b genes amplified by PCR to identify sources of bloodmeals. A total of 21,015 mosquitoes were collected; 5742 within households in the 3 ecosystems and 15,273 within irrigated fields. Mosquitoes collected within irrigated fields belonged to 8 genera and 37 species, while those from households within the irrigation scheme belonged to 6 genera and 29 species. Collections from riverine and pastoral households belonged to five and four genera, respectively. The most abundant genera in the irrigated fields were Aedes (21%) and Mansonia (22%), while Anopheles (43%) was the most abundant within households. Most mosquitoes in riverine and pastoral households belonged to Anopheles (76%) and Aedes (65%) genera, respectively. Seasonal variation driven by rainfall was evidenced by spikes in mosquito numbers within irrigated and riverine ecosystems. Host species identification revealed that goats and humans were the main sources of bloodmeal. There was an overall increase in mosquito abundance and diversity as a result of the presence of the irrigated ecosystem in this county, and an increased availability of highly RVF-susceptible hosts as a result of the establishment and concentration of residential areas, promoting potential vector-host contacts. These results highlight the impact of anthropogenic changes on mosquito ecology, potentially heightening the risk of transmission and maintenance of RVF in this region.
Asunto(s)
Culicidae/virología , Mosquitos Vectores/virología , Virus de la Fiebre del Valle del Rift/aislamiento & purificación , Animales , Ecosistema , Conducta Alimentaria , Interacciones Huésped-Patógeno , Humanos , Kenia/epidemiología , Densidad de Población , Fiebre del Valle del Rift/epidemiología , Fiebre del Valle del Rift/virología , Estaciones del Año , Vertebrados/sangreRESUMEN
OBJECTIVE: The aim of this study was to compare the results of the energy balance of dairy cows calculated with 3 different formulas. The course of the energy balance up to the 100th lactation day in Holstein-Friesian dairy cows from a herd with a mean 305-day milk yield of 11 761 kg was to be described. MATERIALS AND METHODS: Data from a total of 193 dairy cows were available within 2 study periods. Body weight measurements were taken at fixed time points. The feed intake was determined by means of transponder-supported feeding troughs. Milk data was obtained from the corresponding milking recordings. Energy balance was determined by calculation according to the society for nutritional physiology (GfE), Jans and Kessler and National Research Council (NRC) modified according to Collard. RESULTS: The 3 models yielded very similar results. The calculation modified by Collard, however, generally led to lower values. Minimum values for energy balance were calculated in the colostrum phase. The transition from the negative to the positive energy balance occurred in the mean 53 days postpartum. CONCLUSION AND CLINICAL RELEVANCE: All 3 calculation methods were equally suitable to assess energy balance of dairy cows conveying similar results. Over 50 % of the examined cows reach a positive energy balance before the 60th day of lactation. According to the literature, the course of the energy balance with a low point around the 60th day postpartum is not to be assumed in principle for each herd. Strategies to improve negative energy balance with regard to time point, extent, and duration in the early lactation must be developed individually for each herd and still require research.
Asunto(s)
Bovinos/fisiología , Metabolismo Energético/fisiología , Lactancia/fisiología , Leche/metabolismo , Animales , Peso Corporal , Ingestión de Alimentos , Femenino , Vivienda para Animales/clasificaciónRESUMEN
The reliability of reflex-assessment is currently debatable, with current literature regarding the patellar tendon reflex (PTR) as highly reliable, while the biceps tendon reflex (BTR) is regarded to be of low reliability in the dog. Such statements are, however, based on subjective observations rather than on an empirical study. The goals of this study were three-fold: (1) the quantification of the interobserver agreement (IA) on the evaluation of the canine bicipital (BTR) and patellar tendon (PTR) reflex in healthy dogs, (2) to compare the IA of the BTR and PTR evaluation and (3) the identification of intrinsic (sex, age, fur length, weight) and extrinsic (observer´s expertise, body side) risk factors on the IA of both reflexes. The observers were subdivided into three groups based on their expected level of expertise (neurologists = highest -, practitioners = middle-and veterinary students = lowest level of expertise). For the BTR, 54 thoracic limbs were analyzed and compared to the evaluation of the PTR on 64 pelvic limbs. Each observer had to evaluate the reflex presence (RP) (present or absent) and the reflex activity (RA) using a 5-point ordinal scale. Multiple reliability coefficients were calculated. The influence of the risk factors has been calculated using a mixed regression-model. The Odds Ratio for each factor was presented. The higher the level of expertise the higher was the IA of the BTR. For RP(BTR), IA was highest for neurologists and for RA(BTR) the IA was lowest for students. The level of expertise had a significant impact on the degree of the IA in the evaluation of the bicipital tendon reflex: for the RA(BTR), practitioners had a 3.4-times (p = 0.003) and students a 7.0-times (p < 0.001) higher chance of discordance. In longhaired dogs the chance of disagreement was 2.6-times higher compared to shorthaired dogs in the evaluation of RA(BTR) (p = 0.003). Likewise, the IA of the RP(PTR) was the higher the higher the observers´ expertise was with neurologists having significantly highest values (p < 0.001). The RA(PTR) has been evaluated more consistent by practitioners and students than the RA(BTR). For practitioners this difference was significant (< 0.01). Our data suggests that neurologists assess the bicipital and patellar tendon reflex in dogs most reliably. None of the examined risk factors had a significant impact on the degree of IA in the evaluation of RP(PTR), while students had a 4.4-times higher chance of discordance when evaluating the RA(PTR) compared to the other groups. This effect was significant (p < 0.001). Neurologists can reliably assess the bicipital and patellar tendon reflex in healthy dogs. Observer´s level of expertise and the fur length of the dog affect the degree of IA of RA(BTR). The influence of the observer´s expertise is higher on the evaluation of the BTR than on the PTR.
Asunto(s)
Tendones Isquiotibiales/fisiología , Ligamento Rotuliano/fisiología , Reflejo de Estiramiento/fisiología , Animales , Perros , Femenino , Masculino , Variaciones Dependientes del Observador , Oportunidad Relativa , Grabación en VideoRESUMEN
OBJECTIVE: Postpartal disease complexes of dairy cows are frequently related to an insufficient feed intake around calving. The study examined the relationship between the rumen fill (RF) score and the feed intake. A further aim was to evaluate whether the RF score can be used in practice to estimate the cow's individual feed intake (in kg dry mass intake or fresh-mass intake per cow). MATERIAL AND METHODS: In pluriparous cows (nâ =â 109), the RF was scored daily according to the schema of Zaaijer and Noordhuizen (2003) modified by half-points between day 24 (±â 4 days) ante partum (a.â p.) and day 9 post partum (p.â p.) as well as on days 28 (±â 2 days) and 60 (±â 2 days) p.â p. The individual feed intake per cow was recorded. Additionally, measurements of the feed intake were performed every 4 hours over 24 hours (24-hour daily profiles) in 21 cows a.â p. and in 10 cows p.â p. RESULTS: There was a significant relationship between the RF score and the feed intake both a.â p. and p.â p. The number of days in milk greatly influenced this relationship. Immediately p.â p., there was a response in the RF score of half a score with an additional intake of 3.5â kg dry matter, while a.â p., a change of the PF score only occurred when the feed uptake was reduced by 18â kg dry matter. CONCLUSION: During the first week p.â p., the RF score proved to be a sensitive measuring instrument for the individual feed intake. Because of its low response a.â p., it was only suitable for the detection of animals at risk with a considerably reduced feed intake over several days. CLINICAL RELEVANCE: The RF score provides the most informative value during the first week p.â p. to assess the increase in feed intake in the individual cow after calving. It is recommended to score the RF daily during the first 7-9 days p.â p. and to evaluate it individually to detect risk animals with a reduced feed intake. During the dry period, only cows with a significantly reduced feed intake over several days can be detected and consequently treated early to prevent disorders p.â p. During lactation (evaluated on days 28 and 60 p.â p.), the RF score appears to be of very limited informative value regarding the individual feed intake.
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Crianza de Animales Domésticos/métodos , Industria Lechera/métodos , Ingestión de Alimentos , Rumen/fisiología , Alimentación Animal , Animales , Bovinos , Enfermedades de los Bovinos/prevención & control , Femenino , Lactancia/fisiología , Periodo Posparto/fisiologíaRESUMEN
The objective was to determine possible challenge areas that bovine veterinarians may face when working on certified organic livestock operations. All members of the American Association of Bovine Practitioners' electronic mailing list, who practised in the USA, were invited to participate in an anonymous online survey. Veterinarians (n=213) from 38 states participated in the survey. The focus of the survey was on the veterinarian's interest in and perception of organic farming, their knowledge of the use of alternative therapies under federal regulations and their needs for providing veterinary services to organic farms. Most participants worked in dairy practice and served ≥1 organic client. Their attitude towards organic production was balanced. Many veterinarians struggled to offer sick animal care with alternative therapies within the regulatory framework and expressed their need to have more evidence-based alternative therapies. Two-thirds of veterinarians were concerned that the lack of proven effective therapy options would impair livestock welfare on organic farms in the USA. Almost 90 per cent of respondents did not think that organic livestock was healthier than conventionally raised livestock and most participants (74 per cent) thought livestock health was dependent on management rather than organic or conventional farming practices. In summary, participants were generally not opposed to organic farming. However, most veterinarians expressed their need to have a better access to clear information about organic regulations and most importantly more evidence-based alternative therapies to ensure animal health and welfare on organic livestock operations.