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1.
J Dairy Sci ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39033913

RESUMEN

Lameness in dairy cattle is a clinical sign of impaired locomotion, mainly caused by painful foot lesions, compromising the US dairy industry's economic, environmental, and social sustainability goals. Combining technology and on farm data may be a more precise and less labor-intensive lameness detection tool, particularly for early detection. The objective of this observational study was to describe the association between average weekly autonomous camera-based (AUTO) locomotion scores and hoof trimming (HT) data. The AUTO data were collected from 3 farms from April 2022 to March 2023. Historical farm HT data were collected from March 2016 to March 2023 and used to determine cow lesion history and date of HT event. The HT events were categorized as a regular HT (TRIM; n = 2290) or a HT with a lesion recorded (LESION; n = 670). Events with LESION were sub-categorized based on lesion category: digital dermatitis (DD; n = 276), sole ulcer (SU; n = 79), white line disease (WLD; n = 141), and other (n = 174). The data also contained the leg of the LESION, classified as front left (FL; n = 54), front right (FR; n = 146), rear left (RL; n = 281), or rear right (RR; n = 183) leg with 6 events missing the leg. Cows' HT histories were classified as follows: cows with no previous recorded instance of any lesion were classified as TRIM0 (n = 1554). The first instance of any hoof lesion was classified as LESION1 (n = 238). This classification was retained until a subsequent TRIM occurred - recorded as TRIM1 (n = 632). The next unique instance of any lesion following a TRIM1 was classified as LESION2 (n = 86). Any LESION events occurring after LESION1 or LESION2 without a subsequent TRIM were considered a hoof lesion recurrence and classified as LESIONRE1 (n = 164) and LESIONRE2 (n = 22), respectively. TRIM events after LESION2 or LESION2RE (n = 104) or LESION events after LESIONRE1 or LESIONRE2 were classified as LESION_OTHER (n = 160). The AUTO scores from -28 to -1 days prior to the HT event were summarized into weekly scores and included if cows had at least 1 observation per week in the 4 weeks before the event. For all weeks, LESION cows had a higher median AUTO score than TRIM cows. Cows with TRIM0 had the lowest and most consistent median weekly score compared to LESION and other TRIM classifications. Before HT cows with TRIM0 and TRIM1, both had median score increases of 1 across the 4 weeks, while the LESION categories had an increase of 4 to 8. Scores increased with each subsequent LESION event compared to the previous LESION event. Cows with SU lesions had the highest median score across the 4 weeks, WLD had the largest score increase, and DD had the lowest median score and score increase. When grouping a LESION event by leg the hoof lesion was found on, the AUTO scores for four groups displayed comparable median values. Due to the difference between TRIM and LESION events, this technology shows potential for the early detection of hoof lesions.

2.
J Dairy Sci ; 105(9): 7728-7737, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35879157

RESUMEN

Lameness assessments are commonly conducted at a single point in time, but such assessments are subject to multiple sources of error. We conducted a longitudinal study, assessing the gait of 282 lactating dairy cows weekly during the first 12 wk of lactation, with the aim of assessing how lameness prevalence changed in relation to case definition and assessment frequency. Gait was scored using a 5-point scale where scores of 1 and 2 were considered sound, 3 was clinically lame, and 4 and 5 were severely lame. We created 5 lameness definitions using increasingly stringent thresholds based upon the number of consecutive events of locomotion score ≥3. In LAME1, a cow was considered lame when locomotion score was ≥3 at any scoring event, in LAME2, LAME3, LAME4, and LAME5, a cow was considered lame when locomotion score was 3 or higher during 2, 3, 4, and 5 consecutive scoring events, respectively. We also assessed the effect of assessment frequency on measures of prevalence and incidence using weekly assessment (ASSM1), 1 assessment every 2 wk (ASSM2), 1 assessment every 3 wk (ASSM3), and 1 assessment every 4 wk (ASSM4). Using LAME1, 69.2% of cows were considered lame at some point during the trial, with an average point prevalence of 31.8% (SD: 2.8) and average incidence rate of 10.9 cases/100 cow weeks (SD: 3.7). Lameness prevalence decreased to 28.0% when using LAME5. Survival analysis was used to assess the effects of parity, using these different case definitions. Parity is a known risk for lameness, such that case definitions and prevalence estimates should be stratified by parity to inform management decisions. Using the LAME3 criterion, primiparous cows had the highest chance of reaching 12 wk without a lameness event, and fourth and higher parities had the lowest. Weighted linear and quadratic kappa values were used to assess agreement between different assessment frequencies and lameness definitions; we found substantial to excellent agreement between ASSM1 and ASSM2 using LAME1, LAME2, and LAME3 definitions. Agreement was fair to substantial between ASSM1 and ASSM3 and low to fair between ASSM1 and ASSM4. Likewise, the agreement between LAME1 and LAME2 was fair in primiparous cows, substantial in second and third parity cows, and poor to fair in fourth and greater parity cows. We conclude that lameness prevalence estimates are dependent upon case definition and that the use of more stringent case definitions results in fewer cows classified as lame. These results suggest that routine locomotion assessments be conducted at least every 2 wk, and that cows should be defined as lame on the basis of 2 consecutive assessments.


Asunto(s)
Enfermedades de los Bovinos , Cojera Animal , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/etiología , Industria Lechera/métodos , Femenino , Marcha , Lactancia , Cojera Animal/etiología , Estudios Longitudinales , Embarazo , Prevalencia
3.
J Dairy Sci ; 103(11): 10494-10505, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32981735

RESUMEN

Objectives were to evaluate the association between behavior and hoof lesions (HL) in lactating dairy cows. Jersey cows without any visible HL on all 4 legs were enrolled at 20 ± 3 d in milk (DIM), examined for body condition score (BCS), and had an automatic activity monitor (AfiTag II, AfiMilk, Afikim, Israel) attached to their right hind leg. At 120 ± 3 DIM, activity monitors were removed and cows were re-examined for HL and BCS. Cows were classified according to HL status as either healthy or with HL at d 120. Because sole hemorrhage (SH) accounted for over 80% of HL on d 120, SH was reclassified according to the number of feet affected. Daily activity data (daily lying duration, lying bouts, lying bout duration, and number of steps) of 344 cows collected between d 20 and d 120 were analyzed using restricted maximum likelihood linear mixed models with an autoregressive covariance structure. Separate models were built to include specific activities, HL status at d 120, DIM, interaction between lesion status at d 120 and DIM, parity, season of calving, and BCS change from d 20 to d 120 as fixed effects. Cow was included in all models as random effect. Incidence of HL at d 120 was 58.4% (n = 201 out of 344). Compared with healthy cows, cows with HL at d 120 had reduced daily lying duration (-0.53 h; 95% CI: -0.78 to -0.28 h) in the early postpartum period. We found no evidence for a difference in number of lying bouts (0.41; 95% CI: -0.76 to 1.59;), lying bout duration (-3.04 min; 95% CI: -6.6 to 0.49), and number of steps (62.14; 95% CI: -89.62 to 213.91) between cows that remained healthy and those that developed HL. Compared with healthy cows, cows that developed SH in 1 or more feet had reduced daily lying duration in the early postpartum period. Irrespective of lesion status at d 120, daily lying duration and lying bout duration increased from d 20 to d 120, whereas lying bout number and number of steps decreased from d 20 to d 120. We concluded that cows that developed HL had a reduced daily lying duration in the early postpartum period. Therefore, reduced daily lying duration should be considered a risk factor for HL development in lactating dairy cows.


Asunto(s)
Enfermedades de los Bovinos/psicología , Enfermedades del Pie/veterinaria , Pezuñas y Garras/patología , Animales , Conducta Animal , Bovinos , Enfermedades de los Bovinos/patología , Femenino , Enfermedades del Pie/psicología , Israel , Lactancia , Leche , Periodo Posparto , Embarazo , Descanso/psicología , Estaciones del Año
4.
J Dairy Sci ; 103(4): 3401-3413, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32057429

RESUMEN

The objectives of this study were to evaluate the association between hoof lesions and fertility in dairy cows. Lactating Jersey cows (n = 1,639) were enrolled at 20 ± 3 d in milk (D20), examined and treated for presence of hoof lesions (HL), and evaluated for body condition score (BCS). Afterward, they were managed according to standard farm procedures, including estrus detection and presynchronization and a 5 d Cosynch-72 protocol for cows that failed to show estrus. Ovaries were scanned at 27 and 41 ± 3 d in milk, and cows with a corpus luteum greater than 20 mm on at least 1 exam were considered cyclic. At 120 ± 3 d in milk (D120), cows were re-examined for HL and BCS. Cows were classified at D20 according to HL status as healthy (n = 1,197) or having HL (n = 429), and according to HL category as healthy (n = 1,197) or having a sole hemorrhage (n = 280), noninfectious HL (sole ulcer, toe ulcer, or white line disease; n = 113), or infectious HL (digital dermatitis and foot rot; n = 36). Cows with HL at D20 had reduced odds of being cyclic (38.3 vs. 51.9%) and a longer interval from calving to first service (58 vs. 51 d) compared with healthy cows. Cows with infectious HL at D20 had reduced odds of pregnancy to first service (16.7 vs. 38.3%) compared with healthy cows. Cows with sole hemorrhage at D20 were more likely to lose pregnancies between d 32 and 64 after the first service postpartum compared with healthy cows (10.5 vs. 5.2%). Cows with sole hemorrhage at D20 had a smaller hazard of pregnancy (67.9 vs. 75.5%) at 150 d in milk and more days open (88 vs. 77d) compared with healthy cows. To assess the relationship between the development of HL and fertility, cows were classified as healthy (no HL at D20 and D120; n = 308), cured (any HL at D20 and no HL at D120; n = 72), new HL (no HL at D20 and any HL at D120; n = 597), and chronic (any HL at D20 and D120; n = 226). Sole hemorrhage accounted for 93% of new HL. The proportions of cows with HL at D20 and D120 were 26.9 and 68.4%, respectively. We found no evidence for a difference in pregnancy hazard at 150 d in milk between cows that remained healthy (n = 308) and cows that developed new HL (n = 597). Hoof lesions at D20, but not new HL, were associated with decreased odds of cyclicity, longer interval from calving to first service postpartum, and reduced pregnancy hazard in Jersey cows. The effect of an HL diagnosis in early lactation and management to reduce chronic HL in dairy cows warrants further investigation.


Asunto(s)
Enfermedades de los Bovinos/fisiopatología , Fertilidad , Pezuñas y Garras/patología , Cojera Animal/fisiopatología , Animales , Bovinos , Enfermedades de los Bovinos/patología , Cuerpo Lúteo/diagnóstico por imagen , Detección del Estro/métodos , Femenino , Pezuñas y Garras/diagnóstico por imagen , Lactancia , Cojera Animal/patología , Leche , Periodo Posparto , Embarazo
5.
J Dairy Sci ; 102(7): 6383-6390, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31030913

RESUMEN

Hoof pathologies in dairy cows have a major effect on both production and animal welfare. Trimming of excess or diseased hoof tissue is essential for the treatment of many of these conditions. Trimming hoof lesions can cause severe pain, resulting in adverse behavioral responses with risk for animal and human safety. Interventions are usually carried out by nonveterinary technicians in the absence of pain management training. Pain control during trimming is not only an ethical obligation but also allows for better manipulation and more meticulous treatment. The aim of this study was to test the efficacy of Tri-Solfen (Bayer Australia Ltd., Pymble, NSW, Australia), a combination of local anesthetics in a topical gel form, containing lidocaine, bupivacaine, adrenaline, and cetrimide, for the treatment of pain associated with trimming of hoof lesions. Sixty-two Holstein-Frisian cows were selected for trimming at the drying-off period and were visually scored for lameness before entering the chute. After diagnosis of the hoof lesion but before deep trimming was initiated, each animal was randomly distributed to 2 groups: C, usual trimming with no pain control, and T, trimming with a local anesthetic formulation being applied immediately after live corium was exposed. During curative trimming, behavior observation was conducted by 2 observers blind to treatment. In 27 cows, algometry measurements were performed before and after the procedure to assess animal reaction to pressure. Lameness scoring was again performed as the cow left the chute. Nonparametric tests and ANOVA were performed. Results showed that use of the topical anesthetic formulation significantly reduced reaction to trimming and lameness score after trimming when compared with nontreated animals. Algometry values showed increased pressure threshold after application of topical anesthetics. This study suggests that the use of topical local anesthesia with lidocaine and bupivacaine helps reduce pain associated with corrective trimming of severe hoof lesions, enhancing animal welfare and potentially ensuring safety of trimmers.


Asunto(s)
Anestésicos Locales/administración & dosificación , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades del Pie/veterinaria , Pezuñas y Garras/lesiones , Dolor/veterinaria , Anestesia Local , Animales , Australia , Bovinos , Enfermedades de los Bovinos/fisiopatología , Femenino , Enfermedades del Pie/tratamiento farmacológico , Enfermedades del Pie/fisiopatología , Marcha , Pezuñas y Garras/efectos de los fármacos , Masculino , Dolor/tratamiento farmacológico
6.
Transl Anim Sci ; 3(1): 74-83, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32704780

RESUMEN

Lameness is a major animal welfare and economic issue for the dairy industry and is a challenge to overcome due to multifaceted causes. Digital cushion thickness (DCT) is a strong predictor of lameness and is phenotypically associated with incidence of claw horn disruption lesions (CHDL; sole ulcers and white line disease). We hypothesized that DCT varies between digits and across lactation within the cow. This variation could be characterized to predict the occurrence of CHDL or compromised locomotion. BCS, visual locomotion score (VLS), DCT, and presence or absence of lesions were collected at 4 time points: <40 d prepartum (DPP), 1 to 30 d in milk (DIM), 90 to 120 DIM, and ≥255 DIM for 183 commercial Holstein cows enrolled in the study. Cows underwent digital sonographic examination for the measurement of DCT evaluated at the typical sole ulcer site beneath the flexor tuberosity for the right front medial and lateral digits and right hind medial and lateral digits. Factors such as parity number and stage in lactation were obtained from farm management software (DairyComp 305; Valley Agricultural Software, Tulare, CA). Cows were grouped by parity: primiparous (parity = 1) or multiparous (parity ≥ 2). The prevalence of CHDL among time points ranged from 0% to 4.2% for primiparous cows vs. 2.5% to 25% for multiparous cows, whereas the prevalence of lameness based on VLS of 3 to 5 ranged from 1.7% to 8.3% for primiparous cows vs. 12.7% to 33% for multiparous cows. DCT varied within primiparous and multiparous cows based on stage of lactation and digit (P < 0.05) and was thicker for both parity groups prior to dry off (≥255 DIM) and thinnest prior to calving (<40 DPP) and after peak lactation (90 to 120 DIM). The DCT of the front medial digit was thickest for primiparous heifers, whereas the hind lateral digit was thickest for multiparous cows. The DCT of the hind medial digit was thinnest for both parity groups. Parity group and DCT of the hind lateral digit <40 DPP were important predictors of CHDL (P < 0.05), whereas parity group and DCT of the hind lateral digit and front lateral digit at 1 to 30 DIM were key predictors of VLS lameness (P < 0.05). These results may help identify animals with higher odds of developing these diseases by highlighting key time points and specific digits of importance for monitoring. In addition, it improves our biological understanding of the relationship between DCT and lameness.

7.
J Dairy Sci ; 101(7): 6322-6335, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29627245

RESUMEN

The objective of this study was to determine if a 3-dimensional computer vision automatic locomotion scoring (3D-ALS) method was able to outperform human observers for classifying cows as lame or nonlame and for detecting cows affected and nonaffected by specific type(s) of hoof lesion. Data collection was carried out in 2 experimental sessions (5 mo apart). In every session all cows were assessed for (1) locomotion by 2 observers (Obs1 and Obs2) and by a 3D-ALS; and (2) identification of different types of hoof lesions during hoof trimming (i.e., skin and horn lesions and combinations of skin/horn lesions and skin/hyperplasia). Performances of observers and 3D-ALS for classifying cows as lame or nonlame and for detecting cows affected or nonaffected by types of lesion were estimated using the percentage of agreement (PA), kappa coefficient (κ), sensitivity (SEN), and specificity (SPE). Observers and 3D-ALS showed similar SENlame values for classifying lame cows as lame (SENlame comparison Obs1-Obs2 = 74.2%; comparison observers-3D-ALS = 73.9-71.8%). Specificity values for classifying nonlame cows as nonlame were lower for 3D-ALS when compared with observers (SPEnonlame comparison Obs1-Obs2 = 88.5%; comparison observers-3D-ALS = 65.3-67.8%). Accordingly, overall performance of 3D-ALS for classifying cows as lame and nonlame was lower than observers (Obs1-Obs2 comparison PAlame/nonlame = 84.2% and κlame/nonlame = 0.63; observers-3D-ALS comparisons PAlame/nonlame = 67.7-69.2% and κlame/nonlame = 0.33-0.36). Similarly, observers and 3D-ALS had comparable and moderate SENlesion values for detecting horn (SENlesion Obs1 = 68.6%; Obs2 = 71.4%; 3D-ALS = 75.0%) and combinations of skin/horn lesions (SENlesion Obs1 = 51.1%; Obs2 = 64.5%; 3D-ALS = 53.3%). The SPEnonlesion values for detecting cows without lesions when classified as nonlame were lower for 3D-ALS than for observers (SPEnonlesion Obs1 = 83.9%; Obs2 = 80.2%; 3D-ALS = 60.2%). This was translated into a poor overall performance of 3D-ALS for detecting cows affected and nonaffected by horn lesions (PAlesion/nonlesion Obs1 = 80.6%; Obs2 = 78.3%; 3D-ALS = 63.5% and κlesion/nonlesion Obs1 = 0.48; Obs2 = 0.44; 3D-ALS = 0.25) and skin/horn lesions (PAlesion/nonlesion Obs1 = 75.1%; Obs2 = 75.9%; 3D-ALS = 58.6% and κlesion/nonlesion Obs1 = 0.35; Obs2 = 0.42; 3D-ALS = 0.10), when compared with observers. Performance of observers and 3D-ALS for detecting skin lesions was poor (SENlesion for Obs1, Obs2, and 3D-ALS <40%). Comparable SENlame and SENlesion values for observers and 3D-ALS are explained by an overestimation of lameness by 3D-ALS when compared with observers. Thus, comparable SENlame and SENlesion were reached at the expense high number of false positives and low SPEnonlame and SPEnonlesion. Considering that observers and 3D-ALS showed similar performance for classifying cows as lame and for detecting horn and combinations of skin/horn lesions, the 3D-ALS could be a useful tool for supporting dairy farmers in their hoof health management.


Asunto(s)
Enfermedades de los Bovinos/diagnóstico , Pezuñas y Garras , Imagenología Tridimensional/veterinaria , Cojera Animal/diagnóstico , Locomoción , Variaciones Dependientes del Observador , Animales , Bovinos , Femenino , Pezuñas y Garras/patología , Humanos , Observación , Proyectos de Investigación
8.
J Dairy Sci ; 100(4): 2828-2836, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28131577

RESUMEN

A national genetic evaluation program for hoof health could be achieved by using hoof lesion data collected directly by hoof trimmers. However, not all cows in the herds during the trimming period are always presented to the hoof trimmer. This preselection process may not be completely random, leading to erroneous estimations of the prevalence of hoof lesions in the herd and inaccuracies in the genetic evaluation. The main objective of this study was to estimate genetic parameters for individual hoof lesions in Canadian Holsteins by using an alternative cohort to consider all cows in the herd during the period of the hoof trimming sessions, including those that were not examined by the trimmer over the entire lactation. A second objective was to compare the estimated heritabilities and breeding values for resistance to hoof lesions obtained with threshold and linear models. Data were recorded by 23 hoof trimmers serving 521 herds located in Alberta, British Columbia, and Ontario. A total of 73,559 hoof-trimming records from 53,654 cows were collected between 2009 and 2012. Hoof lesions included in the analysis were digital dermatitis, interdigital dermatitis, interdigital hyperplasia, sole hemorrhage, sole ulcer, toe ulcer, and white line disease. All variables were analyzed as binary traits, as the presence or the absence of the lesions, using a threshold and a linear animal model. Two different cohorts were created: Cohort 1, which included only cows presented to hoof trimmers, and Cohort 2, which included all cows present in the herd at the time of hoof trimmer visit. Using a threshold model, heritabilities on the observed scale ranged from 0.01 to 0.08 for Cohort 1 and from 0.01 to 0.06 for Cohort 2. Heritabilities estimated with the linear model ranged from 0.01 to 0.07 for Cohort 1 and from 0.01 to 0.05 for Cohort 2. Despite a low heritability, the distribution of the sire breeding values showed large and exploitable variation among sires. Higher breeding values for hoof lesion resistance corresponded to sires with a higher prevalence of healthy daughters. The rank correlations between estimated breeding values ranged from 0.96 to 0.99 when predicted using either one of the 2 cohorts and from 0.94 to 0.99 when predicted using either a threshold or a linear model.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Pezuñas y Garras , Animales , Cruzamiento , Bovinos , Dermatitis Digital/genética , Femenino , Enfermedades del Pie/veterinaria , Modelos Lineales , Modelos Genéticos , Fenotipo
9.
Prev Vet Med ; 133: 52-63, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27720027

RESUMEN

The importance of lameness in primiparous dairy heifers is increasingly recognised. Although it is accepted that clinical lameness in any lactation increases the risk of future lameness, the impact of foot lesions during the first lactation on long-term lameness risk is less clear. This retrospective cohort study aimed to investigate the impacts of foot lesions occurring around the time of first calving in heifers on future lameness risk, daily milk yield and survival within a dairy herd. Records were obtained for 158 heifers from one UK dairy herd. Heifers were examined in 2 month blocks from 2 months pre-calving through to 4 months post-calving. Sole lesions and white line lesions were scored on a zero to 10 scale and digital dermatitis on a zero to 3 scale. Outcomes investigated were; lameness risk based on weekly locomotion scores, average daily milk yield and culling risk. Mixed effect models were used to investigate associations between maximum lesion scores and outcomes. Lesion scores in the highest score categories for claw horn lesions (sole lesions and white line lesions) in the 2 to 4 month post-calving period were associated with an increased risk of future lameness; heifers with white line lesion scores ≥3 compared with scores zero to 1 and heifers with sole lesion scores ≥4 compared with score 2, at this time point, had a predicted increased risk of future lameness of 1.6 and 2.6 respectively. Sole lesions ≥4 were also associated with a reduction in average daily milk yield of 2.68kg. Managing heifers to reduce claw horn lesions during this time period post-calving may provide health, welfare and production benefits for the long-term future of those animals. A novel finding from the study was that mild lesion scores compared with scores zero to 1, were associated with a reduced risk of future lameness for white line lesions and sole lesions occurring in the pre-calving or 2 to 4 months post-calving periods respectively. Mild sole lesions in the pre-calving period were also associated with a reduced risk of premature culling. One hypothesis for this result is that a mild insult may result in adaptive changes to the foot leading to greater biomechanical resilience and so increased longevity.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades del Pie/veterinaria , Lactancia , Cojera Animal/epidemiología , Longevidad , Leche/metabolismo , Factores de Edad , Animales , Bovinos , Enfermedades de los Bovinos/etiología , Estudios de Cohortes , Femenino , Enfermedades del Pie/epidemiología , Enfermedades del Pie/etiología , Cojera Animal/etiología , Modelos Lineales , Modelos Logísticos , Reproducción , Estudios Retrospectivos , Escocia/epidemiología
10.
J Dairy Sci ; 98(2): 1286-95, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25497826

RESUMEN

Performing a genome-wide association study (GWAS) might add to a better understanding of the development of claw disorders and the need for trimming. Therefore, the aim of the current study was to perform a GWAS on claw disorders and trimming status and to validate the results for claw disorders based on an independent data set. Data consisted of 20,474 cows with phenotypes for claw disorders and 50,238 cows with phenotypes for trimming status. Recorded claw disorders used in the current study were double sole (DS), interdigital hyperplasia (IH), sole hemorrhage (SH), sole ulcer (SU), white line separation (WLS), a combination of infectious claw disorders consisting of (inter-)digital dermatitis and heel erosion, and a combination of laminitis-related claw disorders (DS, SH, SU, and WLS). Of the cows with phenotypes for claw disorders, 1,771 cows were genotyped and these cow data were used for the GWAS on claw disorders. A SNP was considered significant when the false discovery rate≤0.05 and suggestive when the false discovery rate≤0.20. An independent data set of 185 genotyped bulls having at least 5 daughters with phenotypes (6,824 daughters in total) for claw disorders was used to validate significant and suggestive SNP detected based on the cow data. To analyze the trait "trimming status" (i.e., the need for claw trimming), a data set with 327 genotyped bulls having at least 5 daughters with phenotypes (18,525 daughters in total) was used. Based on the cow data, in total 10 significant and 45 suggestive SNP were detected for claw disorders. The 10 significant SNP were associated with SU, and mainly located on BTA8. The suggestive SNP were associated with DS, IH, SU, and laminitis-related claw disorders. Three of the suggestive SNP were validated in the data set of 185 bulls, and were located on BTA13, BTA14, and BTA17. For infectious claw disorders, SH, and WLS, no significant or suggestive SNP associations were detected. For trimming status, 1 significant and 1 suggestive SNP were detected, both located close to each other on BTA15. Some significant and suggestive SNP were located close to SNP detected in studies on feet and leg conformation traits. Genes with major effects could not be detected and SNP associations were spread across the genome, indicating that many SNP, each explaining a small proportion of the genetic variance, influence claw disorders. Therefore, to reduce the incidence of claw disorders by breeding, genomic selection is a promising approach.


Asunto(s)
Enfermedades de los Bovinos/genética , Enfermedades del Pie/veterinaria , Estudio de Asociación del Genoma Completo/veterinaria , Pezuñas y Garras , Crianza de Animales Domésticos/métodos , Animales , Cruzamiento , Bovinos , Enfermedades de los Bovinos/prevención & control , Dermatitis Digital/genética , Femenino , Pie , Enfermedades del Pie/genética , Enfermedades del Pie/prevención & control , Genotipo , Masculino , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Reproducibilidad de los Resultados
11.
Vet J ; 201(1): 116-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24821362

RESUMEN

A circumferential ring in the hoof horn of foals occurs at birth and grows down to the distal border as the fetal hoof is replaced. Horn growth and complete hoof capsule renewal have not been measured in Thoroughbred foals but the determination of time of hoof renewal may allow accurate predictions of healing time to be made in cases of hoof lesions. The objective of this study was to measure the time taken for the fetal hoof of newborn foals to grow to the distal border and be replaced by hoof grown since birth. The age of the foal in days on the day that routine hoof trimming removed the hoof ring of the front hooves was recorded. The mean age at which the fetal hoof was removed was 145 ± 15 days (95% CI, 141.8-147.2), range 120-165 days. Thoroughbred foals replaced the fetal hoof in approximately half the time taken for mature horses (270-365 days).


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Pezuñas y Garras/crecimiento & desarrollo , Caballos/crecimiento & desarrollo , Animales , Factores de Tiempo
12.
Rev. cient. (Maracaibo) ; 16(5): 466-471, oct. 2006. ilus, tab
Artículo en Español | LILACS | ID: lil-630968

RESUMEN

Con la finalidad de determinar la eficacia y eficiencia de la antibioterapia sistémica en la terapéutica de las lesiones podales agudas y sub-agudas, se desarrollo una investigación durante los meses de julio y agosto del año 2000, en dos explotaciones lecheras del estado Zulia, Venezuela, en la cual se evaluaron 29 vacas cojas determinando el grado de claudicación presente y clasificando las diferentes lesiones encontradas en los dígitos. Los animales fueron asignados en tres grupos: dos experimentales (sistémico y local) y uno control, tratando de mantener el mismo reto en cuanto a claudicaciones y lesiones en cada uno, los datos clínicos fueron registrados en fichas individuales. La metodología establecida permitió el chequeo clínico a las 0; 48 y 120 horas con la finalidad de determinar la eficacia comparativa de cada uno de los tratamientos, basado en dos variables respuesta: Grado de claudicación (GC) y Características clínicas de la Lesión (CL). Los resultados mostraron que ambos tratamientos fueron capaces de lograr una reducción en el grado de claudicación (GC) y en las características clínicas de la lesión (CL) de los animales, al compararlos con el grupo control (P < 0,05). Sin embargo, en relación a la eficiencia (costos del tratamiento) el uso del tratamiento local resultó superior al tratamiento sistémico, recomendándose su difusión y aplicación para la terapéutica de las lesiones podales.


With the goal to determine the efficacy and efficiency of the systemic antibiotherapy on the acute and sub acute hoof lesions a research was developed in two milking farms at Zulia state, Venezuela. In a period within July and August 2000, 29 cows were evaluated to determine the degree of lameness and to classify the different lesions founds at the digits. The experimental animals were group in three lots: two experimental groups (treated either intramuscular or local) and one control group. As far as it was possible the three groups were maintained with the same challenge in relation of lameness and lesions in each one. The clinical data were recorded individually. The established method allowed to monitor the animals at 0; 48: 120 h with the goal to determine the efficacy and efficiency of each treatment supported by two variable responds: grade of lameness (GC) and the clinical characteristics of lesions (CL). The results showed that both treatments were able to diminish the degree of lameness (GC) and over the clinical characteristics of lesions (CL) of experimental animals when it was compared with the control group (P < 0.05). However in relation to efficiency (treatment cost), the use of local treatment was better than the systemic treatment. Therefore its promotion and application is recommended for the treatment of hoof lesions.

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