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1.
J Dairy Sci ; 104(5): 5921-5931, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33663849

RESUMEN

Claw lesions are a serious problem on dairy farms, affecting both the health and welfare of the cow. Automated detection of lameness with a practical, on-farm application would support the early detection and treatment of lame cows, potentially reducing the number and severity of claw lesions. Therefore, in this study, a method was proposed for the detection of claw lesions based on the acoustic analysis of a cow's gait. A panel was constructed to measure the impact sound of animals walking over it. The recorded impact sound was edited, and 640 sound files from 64 cows were analyzed. The classification of animal-lameness status was performed using a machine-learning process with a random forest algorithm. The gold standard was a 2-point scale of hoof-trimming results (healthy vs. affected), and 38 properties of the recorded sound files were used as influencing factors. A prediction model for classifying the cow lameness was built using a random forest algorithm. This was validated by comparing the reference output from hoof-trimming with the model output concerning the impact sound. Altering the likelihood settings and changing the cutoff value to predict lame animals improved the prediction model. At a cutoff at 0.4, a decreased false-negative rate was generated, and the false-positive rate only increased slightly. This model obtained a sensitivity of 0.81 and a specificity of 0.97. With this procedure, Cohen's Kappa value of 0.80 showed good agreement between model classification and diagnoses from hoof-trimming. In summary, the prediction model enabled the detection of cows with claw lesions. This study shows that lameness can be detected by machine learning from the impact sound of hoofs in dairy cows.


Asunto(s)
Enfermedades de los Bovinos , Pezuñas y Garras , Acústica , Animales , Bovinos , Enfermedades de los Bovinos/diagnóstico , Industria Lechera , Granjas , Femenino , Cojera Animal/diagnóstico , Aprendizaje Automático
2.
Avian Pathol ; 49(3): 230-242, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31971459

RESUMEN

The assessment of bird-based welfare indicators plays an important role in the evaluation of bird welfare. The aim of the study was to histologically validate a visual scoring system for hock burn in broilers and to detect threshold values of a visual score to define welfare-relevant alterations in terms of mild lesions or ulcers of the hock. We collected 200 hocks of 39- to 42-day-old Ross 308 broilers after the slaughter process. Each hock was scored visually ("macro scores" 0-4) and evaluated histologically ("micro scores" 0-3), with high scores representing more severe lesions. Although we found a tendency for higher micro scores with increasing macro scores, an exact allocation of macro to micro scores was not possible. For example, macro score 1 could represent micro scores 1, 2 and 3, whereas macro scores 3 and 4 always represented micro score 3 (ulcer). The conditional probability of certain micro scores for given macro scores was estimated using a multinomial logistic regression model. Ulcer showed the highest probability at macro score 1, whereas mild lesions were not found to have an estimated highest probability at any macro score. The depth of inflammation of hock burn lesions increased with increasing macro scores up to macro score 3 with an average depth of 1019 µm. Visually more severe and deeper lesions were also histologically rated with higher scores. Thus, considering limitations, the herein validated macroscopic assessment scheme for hock burn allows an estimation of histological alterations in hocks of broilers.RESEARCH HIGHLIGHTS Histological validation of a visual assessment scheme for hock burn in broilers.Tendency for higher micro scores with increasing macro scores.Estimation of histological score via macro score possible with limitations.Histological depth of inflammation increased with an increasing macro score.


Asunto(s)
Pollos , Dermatitis/veterinaria , Enfermedades de las Aves de Corral/clasificación , Tarso Animal/patología , Crianza de Animales Domésticos , Bienestar del Animal , Animales , Dermatitis/clasificación , Dermatitis/patología , Enfermedades de las Aves de Corral/patología
3.
Poult Sci ; 103(1): 103243, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37980765

RESUMEN

Like other members of the species Gallus gallus, fast-growing broilers are motivated to perch. However, broilers in the European Union are kept in unstructured barns, with no opportunity to sit elevated and rest undisturbed. A possible solution to this problem is elevated platforms. The aim of this study was to evaluate the use of an elevated platform with perforated surface and manure belt by fast-growing broilers. On 2 commercial farms, an elevated platform was installed in 1 barn per farm. Approximately 35,000 Ross 308 broilers were housed in each barn for 3 fattening periods. On 1 d per wk, the number of broilers per m² on the platform and the ramp was determined every 30 min from video recordings. Besides, focal animals were observed to analyze their behavior on the platform at different ages and during light and dark periods. Broilers used the elevated platform and the ramp from the first week until the end of the fattening period (platform: 9.92 broilers per m², ramp: 6.47 broilers per m²), with a peak in the fourth week of life (platform: 13.00 broilers per m²). In wk 2, 4, and 5, platform use was higher during the light period than during the dark period. Broilers stayed longer on the platform in the dark period (dark: 01:54:23 [hh:mm:ss], light: 00:19:54 [hh:mm:ss]). In every phase of the fattening period, broilers on the platform were inactive to a high proportion (on average 80.60%). This indicates that broilers used the platform also for resting behavior. Thus, the elevated platform with perforated surface and manure belt is a suitable option to structure broiler barns. It allows the broilers to sit elevated and provides additional space. Factors such as a shallow ramp incline of 20°, wide ramps, and appropriate material used for the surface and ramps may have contributed to its high use by broilers of all ages. Further research is needed to evaluate the design of platforms that allow broilers to rest undisturbed.


Asunto(s)
Pollos , Estiércol , Animales , Granjas , Vivienda para Animales
4.
Vet Anim Sci ; 8: 100065, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32734083

RESUMEN

This study investigates air hygienic characteristics of housing systems without fixation for lactating sows, with a focus on microbiological air quality. For animal welfare considerations, free-farrowing systems have been developed to replace those with farrowing crates (FC) and are currently available on the market. A group housing system (GH) for six lactating sows, a single loose-housing system (LH), and a conventional system with FC were tested. By maintaining similar management conditions, microbiological air quality was examined in eight batches with 148 farrowings in total with samplings at the beginning, in the middle, and at the end of the occupancy period of 33 days. No significant differences between the systems were observed in the concentration of total airborne bacteria (TAB), haemolytic streptococci (HS), molds, or yeasts. However, the concentrations of TAB and HS increased significantly over time. Additionally, significant correlations were detected for LH and FC between TAB and HS, and between TAB and carbon dioxide; significant correlations between TAB and inside temperature and total animal weight were revealed only in GH. Significant correlations between TAB and both the dust and inside humidity parameters were found only in FC. Given these results, it was shown that the free-farrowing systems used here do not necessarily lead to poorer microbiological air quality.

5.
FEBS Lett ; 491(1-2): 137-42, 2001 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-11226436

RESUMEN

This study describes the biochemical characterisation of the catalytic domain of membrane-type 6 matrix metalloproteinase (MT6-MMP, MMP25, leukolysin). Its activity towards synthetic peptide substrates, components of the extracellular matrix and inhibitors of MMPs was studied and compared with MT1-MMP, MT4-MMP and stromelysin-1. We have found that MT6-MMP is closer in function to stromelysin-1 than MT1 and MT4-MMP in terms of substrate and inhibitor specificity, being able to cleave type-IV collagen, gelatin, fibronectin and fibrin. However, it differs from stromelysin-1 and MT1-MMP in its inability to cleave laminin-I, and unlike stromelysin-1 cannot activate progelatinase B. Our findings suggest that MT6-MMP could play a role in cellular migration and invasion of the extracellular matrix and basement membranes and its activity may be tightly regulated by all members of the TIMP family.


Asunto(s)
Matriz Extracelular/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Anticuerpos Monoclonales , Western Blotting , Dominio Catalítico , Electroforesis en Gel de Poliacrilamida , Matriz Extracelular/enzimología , Proteínas Ligadas a GPI , Humanos , Hidrólisis , Metaloproteinasa 3 de la Matriz/química , Metaloproteinasa 3 de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz , Metaloproteinasas de la Matriz/química , Metaloproteinasas de la Matriz Asociadas a la Membrana , Metaloendopeptidasas/química , Metaloendopeptidasas/metabolismo , Pliegue de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato
6.
FEBS Lett ; 478(1-2): 52-6, 2000 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-10922468

RESUMEN

Matrix metalloproteinase (MMP)-19 and MMP-20 (enamelysin) are two recently discovered members of the MMP family. These enzymes are involved in the degradation of the various components of the extracellular matrix (ECM) during development, haemostasis and pathological conditions. Whereas MMP-19 mRNA is found widely expressed in body tissues, including the synovium of normal and rheumatoid arthritic patients, MMP-20 expression is restricted to the enamel organ. In this study we investigated the ability of MMP-19 and MMP-20 to cleave two of the macromolecules characterising the cartilage ECM, namely aggrecan and the cartilage oligomeric matrix protein (COMP). Both MMPs hydrolysed aggrecan efficiently at the well-described MMP cleavage site between residues Asn(341) and Phe(342), as shown by Western blotting using neo-epitope antibodies. Furthermore, the two enzymes cleaved COMP in a distinctive manner, generating a major proteolytic product of 60 kDa. Our results suggest that MMP-19 may participate in the degradation of aggrecan and COMP in arthritic disease, whereas MMP-20, due to its unique expression pattern, may primarily be involved in the turnover of these molecules during tooth development.


Asunto(s)
Proteínas de la Matriz Extracelular/metabolismo , Glicoproteínas/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Metaloendopeptidasas/metabolismo , Proteoglicanos/metabolismo , Agrecanos , Secuencia de Aminoácidos , Animales , Artritis Reumatoide/enzimología , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Western Blotting , Cartílago/citología , Cartílago/enzimología , Cartílago/metabolismo , Proteína de la Matriz Oligomérica del Cartílago , Dominio Catalítico , Bovinos , Electroforesis en Gel de Poliacrilamida , Matriz Extracelular/química , Matriz Extracelular/enzimología , Matriz Extracelular/metabolismo , Proteínas de la Matriz Extracelular/química , Glicoproteínas/química , Humanos , Lectinas Tipo C , Proteínas Matrilinas , Metaloproteinasa 20 de la Matriz , Metaloproteinasas de la Matriz/química , Metaloproteinasas de la Matriz/genética , Metaloproteinasas de la Matriz Secretadas , Metaloendopeptidasas/química , Metaloendopeptidasas/genética , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Proteoglicanos/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia/genética , Especificidad por Sustrato , Porcinos , Diente/citología , Diente/enzimología , Diente/metabolismo
7.
J Neurosci ; 20(14): 5225-33, 2000 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10884306

RESUMEN

Double (plp-/-mag-/-) and triple (plp-/-mbp-/-mag-/-) null-allelic mouse lines deficient in proteolipid protein (PLP), myelin-associated glycoprotein (MAG), and myelin basic protein (MBP) were generated and characterized genetically, biochemically, and morphologically including their behavioral capacities. The plp-/-mag-/- mutant develops a rapidly progressing axon degeneration in CNS with severe cognitive and motor coordinative deficits but has a normal longevity. CNS axons of the plp-/-mbp-/-mag-/- mouse are hypomyelinated and ensheathed by "pseudomyelin" with disturbed protein and complex lipid composition. The shiverer trait in the plp-/-mbp-/-mag-/- similar to the plp-/-mbp-/- mutant is significantly ameliorated, and its lifespan is considerably prolonged. The longevity of these dysmyelinosis mouse mutants recommends them as suitable models for the long-term evaluation of stem cell therapeutic strategies.


Asunto(s)
Axones/patología , Enfermedades Desmielinizantes/fisiopatología , Proteína Básica de Mielina/deficiencia , Proteína Proteolipídica de la Mielina/deficiencia , Vaina de Mielina/metabolismo , Glicoproteína Asociada a Mielina/deficiencia , Animales , Conducta Animal , Sistema Nervioso Central/metabolismo , Sistema Nervioso Central/ultraestructura , Enfermedades Desmielinizantes/patología , Regulación de la Expresión Génica , Genotipo , Lípidos de la Membrana/biosíntesis , Ratones , Ratones Mutantes Neurológicos , Proteína Básica de Mielina/genética , Proteína Proteolipídica de la Mielina/genética , Vaina de Mielina/genética , Vaina de Mielina/ultraestructura , Glicoproteína Asociada a Mielina/genética , Conducción Nerviosa , Nervios Periféricos/metabolismo , Nervios Periféricos/ultraestructura , Fenotipo , Transcripción Genética
8.
J Biol Chem ; 275(20): 14809-16, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10809722

RESUMEN

We have recently cloned MMP-19, a novel matrix metalloproteinase, which, due to unique structural features, was proposed to represent the first member of a new MMP subfamily (Pendás, A. M., Knäuper, V. , Puente, X. S., Llano, E., Mattei, M. G., Apte, S., Murphy, G., and López-Otin, C. (1997) J. Biol. Chem. 272, 4281-4286). A recombinant COOH-terminal deletion mutant of MMP-19 (proDelta(260-508)MMP-19), comprising the propeptide and the catalytic domain, was expressed in Escherichia coli, refolded, and purified. Interestingly, we found that proDelta(260-508)MMP-19 has the tendency to autoactivate, whereby the Lys(97)-Tyr(98) peptide bond is hydrolyzed, resulting in free catalytic domain. Mutation of two residues (Glu(88) --> Pro and Pro(90) --> Val) within the propeptide latency motif did not prevent autoactivation but the autolysis rate was somewhat reduced. Analysis of the substrate specificity revealed that the catalytic domain of MMP-19 was able to hydrolyze the general MMP substrate Mca-Pro-Leu-Gly-Dpa-Ala-Arg-NH(2) and, with higher efficiency, the stromelysin substrate Mca-Pro-Leu-Ala-Nva-Dpa-Ala-Arg-NH(2). Kinetic analysis of the interactions of the catalytic domain of MMP-19 with the natural MMP inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), showed strong inhibition using TIMP-2, TIMP-3, and TIMP-4, while TIMP-1 was less efficient. We also demonstrated that synthetic hydroxamic acid-based compounds efficiently inhibited the enzyme. The catalytic domain of MMP-19 was able to hydrolyze the basement membrane components type IV collagen, laminin, and nidogen, as well as the large tenascin-C isoform, fibronectin, and type I gelatin in vitro, suggesting that MMP-19 is a potent proteinase capable of hydrolyzing a broad range of extracellular matrix components. Neither the catalytic domain nor the full-length MMP-19 was able to degrade triple-helical collagen. Finally, and in contrast to studies with other MMPs, MMP-19 catalytic domain was not able to activate any of the latent MMPs tested in vitro.


Asunto(s)
Metaloendopeptidasas/química , Metaloendopeptidasas/metabolismo , Secuencia de Aminoácidos , Membrana Basal/metabolismo , Dominio Catalítico , Clonación Molecular , Escherichia coli , Humanos , Metaloproteinasas de la Matriz Secretadas , Datos de Secuencia Molecular , Mutagénesis , Oligopéptidos/química , Oligopéptidos/metabolismo , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Reacción en Cadena de la Polimerasa , Desnaturalización Proteica , Pliegue de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia , Especificidad por Sustrato
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