Ingestive behavior of Holstein × Zebu cows managed on deferred supplemented pasture

This study aimed to evaluate the ingestive behavior of F1 Holstein × Zebu cows grazing on deferred pasture receiving different supplementation strategies. The experimental design was completely randomized, in a 3×4 factorial, with three supplementation strategies and four evaluation periods. The ingestive behavior of 24 cows divided into three groups of supplementation provided at milking was observed, and two of these groups received protein in the pasture. Ingestive behavior was monitored every 10 minutes for 24 hours and analyzed in the form of periods (morning, afternoon, night, and dawn) and total time. The animals remained longer grazing during the afternoon when the BGHI presented values of 83.8. Protein consumption did not influence grazing time but interfered with forage consumption. For the total grazing time, the animals in group 2 spent less time grazing. The groups of animals presented no difference concerning the time spent on rumination and idleness. During night and dawn, when the climate was characterized as thermal comfort, the animals spent more time ruminating. The climatic conditions did not influence the ingestive behavior, as the grazing peak was observed at times of higher BGHI. However, supplementation of the animals in group 2 modified the ingestive behavior of F1 H × Z cows.

Deeper exploration of inflammatory cell populations in milk to monitor udder health in dairy cows

The present study explored the predictive values of milk leukocyte differentials (MLD) as a basis for improving the diagnosis of intramammary infections (IMIs) and subclinical mastitis. Quarter milk samples were collected for bacteriological analysis, quarter somatic cell count (qSCC), and MLD. The MLD were assessed using the cytospin technique, direct microscopic smears, and flow cytometry. The predictive values of each single leukocyte population and useful potential indices that could better reflect immune complexity were also calculated. Changes in the percentage of any leukocyte alone failed to substantially improve the predictive value of qSCC in diagnosing IMIs. Although certain parameters increased the area under the receiver operating characteristic curve (ROC curve) as a result of increased specificity values, a slight reduction in sensitivity was observed. The so-called CD8 complex was a unique parameter which improved both the sensitivity (78.79 %) and the specificity (80.77 %) in IMI diagnosis, resulting in the highest area under the ROC curve (0.87). To diagnose subclinical mastitis, the percentage of macrophages and the sum of the percentage PMNLs and T CD8+ cells divided by the percentage of macrophages showed the highest predictive values (sensitivity = 79.63, specificity = 73.68, and area under the ROC curve = 0.83) in the differentiation of the inflammatory condition status of cows. In conclusion, this study provides further insights into using T CD8+ lymphocytes in diagnosing bovine IMIs, combined with PMNLs and macrophages. The antidromic trend of macrophages vs. PMNLs and T CD8+ lymphocytes due to the increasing qSCCs was crucial to differentiating quarters under both inflammatory and non-inflammatory conditions.

Diagnóstico precoce de acetonemia subclínica em vacas holandesas por mensuração de corpos cetônicos / Early diagnosis of subclinical acetonemia in holstein cows by measuring ketone bodies / Diagnóstico precoz de acetonemia subclínica en vacas holstein mediante la medición de cuerpos cetónicos

O trabalho foi realizado em uma fazenda de exploração leiteira em Castrolanda, no município de Castro ­ PR. O sistema de manejo é free-stall, com 220 vacas da raça Holandesa com RHA305 de 6.740 litros. Foram coletadas amostras de sangue de 18 vacas de pré-parto, 4 dias antes da data prevista para o parto; e nos dias 4, 7 e 12 pós-parto, mediante punção venosa coccígea, utilizando-se SnapTest digital Ketovet®, constituindo 72 amostras, no período de fevereiro a maio de 2020. Em 4 vacas o BHB do sangue total apresentou-se acima do limite para cetose subclínica no quarto dia após o parto e 17 apresentaram-se acima do limite no sétimo dia, declinando em seguida, principalmente devido às intervenções clínicas. As médias e desvios-padrão foram: D - 4: 0,89 ± 0,257061; D 4: 1,05 ± 0,283279; D 7: 1,81 ± 0,456131; e D 12: 1,19 ± 0,437762. O benefício do monitoramento de BHB foi a imediata intervenção clínica, evitando-se a severidade por instalação de quadro clínico e as enfermidades concomitantes.(AU)

The study was carried out on a dairy farm in Castrolanda, in the county of Castro - PR. The management system is free stall, with 220 Holstein cows with RHA305 of 6,740 liters. Blood samples were collected from 18 pre-calving cows, 4 days before the expected date of calving; and on days 4, 7 and 12 postpartum, by means of coccygeal venipuncture, using SnapTest digital Ketovet®, constituting 72 samples, from February to May 2020. In 4 cows the BHB of whole blood was shown above the limit for subclinical ketosis on the fourth day after delivery and 17 presented above the limit on the seventh day, then declining mainly due to clinical interventions. The means and standard deviations were D -4: 0.89 ± 0.257061; D 4: 1.05 ± 0.283279; D 7: 1.81 ± 0.456131; and D 12: 1.19 ± 0.437762. The benefit of monitoring BHB was immediate clinical intervention, avoiding clinical ketosis and concomitant illnesses.(AU)

El estudio se realizó en una explotación lechera de Castrolanda, en la comarca de Castro - PR. El sistema de manejo es estabulación libre, con 220 vacas Holstein con RHA305 de 6.740 litros. Se recogieron muestras de sangre de 18 vacas pre- parto, 4 días antes de la fecha prevista de parto; y en los días 4, 7 y 12 postparto, mediante venopunción coccígea, utilizando SnapTest digital Ketovet®, constituyendo 72 muestras, desde febrero a mayo de 2020. En 4 vacas la BHB de sangre total se mostró por encima del límite para cetosis subclínica en el cuarto día después del parto y 17 presentaron por encima del límite en el séptimo día, disminuyendo después debido principalmente a intervenciones clínicas. Las medias y desviaciones estándar fueron D -4: 0,89 ± 0,257061; D 4: 1,05 ± 0,283279; D 7: 1,81 ± 0,456131; y D 12: 1,19 ± 0,437762. El beneficio de monitorizar la BHB fue la intervención clínica inmediata, evitando la cetosis clínica y las enfermedades concomitantes.(AU)

Epidemiological and anatomopathological findings of type 1 and 2 abomasum ulcers in cattle with different comorbidities / Achados epidemiológicos e anatomopatológicos de úlceras do abomaso tipo 1 e 2 em bovinos com diferentes comorbidades primárias

This study aimed to investigate the epidemiological and pathological findings of type 1 and 2 abomasal ulcers in cattle with different primary comorbidities. A total of 201 animals; 40/201 (20%) were young cattle under the age of two years and 161/201 (80%) were adult cattle over the age of two years, which were hospitalized for clinical care 152/201 (75,62%), 19/201 (9,45%) obstetric care, 17/201 (8,46%) surgical care and 13/201 (6,47%) for anatomopathological diagnosis, being euthanized or had natural death. The diagnosis of ulcers was based on the result of the post-mortem examination (macroscopic and histopathological analysis). Histopathological examination was performed on 201 fragments of ulcers and classified as type 1 or type 2. Of these, 193/201 (96.01%) corresponded to type 1 ulcers, of which 12/193 (5.97%) corresponded to subtype 1a lesions, 101/193 (50.25%) to subtype 1b, 77/ 193 (38.31%) to subtype 1c, 03/193 (1.49%) to subtype 1d, while 08/201 (3.98%) were type 2 ulcers. The ulcers were characterized by a focal, focally extensive, multifocal or diffuse inflammatory process, mainly by mononuclear cells. Abomasitis associated with ulcerated mucosa was found in 160/201 (79.60%). In 26/201 (12.93%) the abomasitis had diffuse foci of multifocal lymphocytic proliferation by atypical lymphocytes. Digestive and reproductive comorbidities were seen more frequently in cattle with type 1 or type 2 ulcers. The Subtype 1b focal ulcers and subtype 1a and 1b multifocal ulcers were more prevalent. In addition to the presence of comorbidities, most cases occur in the dry period, associated with feeding with higher amounts of concentrates and silages.(AU)

Objetivou-se estudar os achados epidemiológico e anatomopatológico de úlceras do abomaso tipo 1 e 2 em bovinos com diferentes comorbidades primárias. Um total de 201 animais; 40/201 (20%) eram bovinos jovens com idade inferior a dois anos e 161/201 (80%) eram bovinos adultos com idade superior a dois anos, os quais foram internados para atendimento clínico 152/201 (75,62%), 19/201 (9,45%) obstétrico, 17/201 (8,46%) para atendimento clínico-cirúrgico e 13/201 (6,47%) para diagnóstico anatomopatológico, sendo eutanasiados ou tiveram morte natural. O diagnóstico das úlceras foi baseado no exame post-mortem (análise macroscópica e histopatológica). O exame histopatológico foi realizado em 201 fragmentos de úlceras e classificado como tipo 1 ou do tipo 2. Destes, 193/201 (96,01%) corresponderam a úlceras tipo 1, das quais, 12/193 (5,97%) corresponderam a lesões subtipo 1a, 101/193 (50,25%) a subtipo 1b, 77/193 (38,31%) a subtipo 1c, 03/193 (1,49%) ao subtipo 1d, enquanto 08/201 (3,98%) foram úlceras tipo 2. As úlceras foram caracterizadas por processo inflamatório focal, focalmente extenso, multifocais ou difusos, principalmente por células mononucleares. Abomasite associada à mucosa ulcerada foi encontrada em 160/201 (79,60%). Em 26/201 (12,93%) a abomasite apresentava focos difusos de proliferação linfocítica multifocal por linfócitos atípicos. As comorbidades digestivas e reprodutivas foram observadas com maior frequência em bovinos com úlceras tipo 1 ou tipo 2. As úlceras focais subtipo 1b e úlceras multifocais subtipo 1a e 1b foram mais prevalentes. Além da presença de comorbidades, a maioria dos casos ocorrerem no período seco, associados à alimentação com maiores aportes de concentrados e silagens.(AU)

A principal component analysis required in technical assistance guidance for chilled raw milk producers

The purpose of the present study was to evaluate the principal component analysis (PCA) to guide technical assistance regarding several dairy farms' issues, which includes improving microbiological quality and physical-chemical composition of raw refrigerated milk. Data of monthly analysis of fat, protein, lactose, dry defatted stratum, somatic cell count, total bacterial count, milk temperature of 8,101 samples of milk from expansion tanks and production of 78 farms located in the northern region of Minas Gerais, Brazil were processed. Descriptive statistical measures and Pearson correlation coefficient were estimated involving all evaluated traits during the dry and rainy seasons. In addition, multivariate analyses were performed using PCA. The results showed that two farm sites were negatively related to milk quality in both seasons. One farm stood out positively, being able to be used as a herd management model to drive technical assistance actions. Thus, PCA is efficient in simplifying large amounts of data, allowing simpler and faster technical herd management interpretation.(AU)

Evaluation of techniques for diagnosis of Trypanosoma vivax infections in naturally infected cattle in the Zona da Mata Mineira / Avaliação de técnicas para diagnóstico de infecções por Trypanosoma vivax em bovinos naturalmente infectados na Zona da Mata Mineira

Abstract This study aimed to evaluate diagnostic techniques for trypanosomiasis, caused by Trypanosoma vivax, in naturally infected cattle in Minas Gerais, Zona da Mata. The deaths of six lactating cows with similar clinical conditions—characterized by hyporexia, hypogalactia, and recumbency—had been reported from one property. Initially, two animals were examined and diagnosed with trypanosomiasis through identification of the protozoan in a blood smear. After the initial diagnosis, all lactating cows (n=37) on the property were examined, and blood samples were collected for tests including whole blood smear, buffy coat smear, Woo's technique, enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction (PCR). Woo's test, buffy coat smears, and whole blood smears indicated that 4/37 (10.81%) animals were positive for trypanosomiasis, whereas ELISA and PCR indicated that 33/37 (89.19%) and 27/37 (72.97%) animals, respectively, were positive. The agreement obtained between parasitological techniques was classified as high, while between ELISA and PCR, no agreement. In conclusion, parasitological techniques have a low capacity to identify infected animals in the chronic stage of T. vivax infection. Therefore, techniques such as PCR and/or ELISA should be used to minimize the occurrence of false negatives.

Resumo Este estudo objetiva avaliar as técnicas de diagnóstico da tripanossomíase, causada pelo Trypanosoma vivax, em bovinos naturalmente infectados, em Minas Gerais, Zona da Mata. A morte de seis vacas em lactação com condições clínicas semelhantes - caracterizadas por hiporexia, hipogalaxia e decúbito - foi relatada em uma propriedade. Inicialmente, dois animais foram examinados e diagnosticados com tripanossomíase através da identificação do protozoário em esfregaço sanguíneo. Após o diagnóstico inicial, todas as vacas em lactação (n = 37) na propriedade foram examinadas, e amostras de sangue foram coletadas para testes, incluindo esfregaço de sangue total, esfregaço de capa leucocitária, técnica de Woo, ensaio imunoenzimático (ELISA) e reação em cadeia da polimerase (PCR). O teste de Woo, os esfregaços de capa leucocitária e de sangue total indicaram que 4/37 (10,81%) animais foram positivos para tripanossomíase, enquanto ELISA e PCR indicaram que 33/37 (89,19%) e 27/37 (72,97%) animais, respectivamente, foram positivos. A concordância entre técnicas parasitológicas foi classificada como alta, enquanto entre ELISA e PCR, sem concordância. As técnicas parasitológicas apresentam baixa capacidade para identificar animais infectados na fase crônica da infecção por T. vivax. Dessa forma, técnicas como PCR e/ou ELISA devem ser utilizadas para minimizar a ocorrência de falsos negativos.

Ketosis in dairy cows during early lactation - detection in pooled blood serum samples

Background: Ketosis is the most important metabolic disease with prevalence from 15 to 45%. Ketosis is diagnosed using a metabolic profile. Due to the high prevalence, it is necessary to determine a large number of metabolic profiles within farm, which represents an additional cost, so the implementation of pooled serum in assessing the metabolic status of cows was examined. The aim of this study was to validate and evaluate the influence of the relative position (Z-score) of the value of pooled sample metabolic parameters within the known reference value of healthy cows in the detection of ketosis in herd during early lactation. Materials, Methods & Results: The experiment has been carried out using blood samples collected by puncture of coccygeal vein from 50 ketotic and 50 healthy cows. Laboratory analysis includes determination of beta-hydroxybutyrate-BHB, non-esterified fatty acids-NEFA, cholesterol-CHOL, triglycerides-TGC, glucose-GLU, albumin-ALB, total protein-TPROT, UREA, Ca, P, total bilirubin-TBIL and aspartat aminotransferase-AST. The pooled serum was made from 10 individual samples originating from 10 different cows. A serum aliquot of 0.1 mL was taken from each sample, and a 1 mL volume of pooled serum was finally formed. Three types of serum pools were made: 1) 30 pooled sample were from ketosis; 2) 30 pooled sample were from healthy cows and 3) 60 pooled samples containing mixed sera of healthy cows and cows with ketosis were made as follows: 10 pools contain 10% to 60% of ketotic cows (1/10 to 6/10 samples). Statistical analysis includes: a) difference in metabolite concentration and Z-score in pooled sample and arithmetic mean individual sample in healthy and ketotic cow, b) correlation between Z-score of pooled sample and arithmetic mean of individual sample, c) ability of Z-score of metabolite to divide ketotic from healthy cow, d) correlation between Z-score and % of ketotic cow in pooled sample; and e) calculation of 95%CI of pooled sample Z-scores for each % of ketotic cow in pools. Z-score and all analysis were calculated for each metabolic parameter. The results of the study show that the mean values and Zscores of the pool and the calculated average value of the individual samples participating in that pool differ significantly in healthy cows and cows in ketosis, except for TPROT and Ca. A higher value and a higher Z-score were found for BHB, NEFA, UREA, TBIL and AST, and a lower value and a lower Z-score for TGC, CHOL, GLU, ALB and P in ketotic cows compared to healthy cows. The value of the Z-score of the pooled sample and the calculated mean values of individual samples participating in the pool are highly correlated with each other (coefficient of determination over 99%). Z-score of metabolites in the pooled sample can be used to distinguish healthy from ketotic cows (ROC AUC= 0.711 to 0.989), except for TPROT and Ca. The Z-score value of the pooled sample shows a linear correlation with the percentage of ketotic cows in the pool and the reference ranges of Z-scores change significantly as a function of the percentage of ketosis cows. Discussion: Modern research on the metabolic profile in cows requires obtaining a large amount of information from as few samples as possible. The advantages of using the Z-score are reflected in the following: this score does not depend on the absolute value of the metabolite, but on the position within the known population reference value, Z-score of sample and the arithmetic mean of individual samples included in the same pool are almost identical, the Z-score of these 2 groups of results is ideally correlated, the Z-score significantly correlates with the % of ketosis samples in the pooled sample. The use of pooled sample Z-score can be a useful in a herd level assessment of metabolic status and detection of ketosis as most important metabolic disease in dairy cows.

Stephanofilariasis in Holstein cows - Diagnostic approach

Background: Stephanofilariasis is a parasitic disease caused by the nematode Stephanofilaria spp., considered a zoonotic disease, that affects several species, mainly dairy cattle. The condition causes chronic ulcerative dermatitis, due to the mechanical action of the parasite on the hair follicles and dermal papillae. The recommended diagnostic method is histopathological examination, but alternative methods have been studied for the detection of the agent since it does not demonstrate good results. There is no specific treatment, however, the use of organophosphates is recommended. The objective of this work is to report an outbreak of stephanofilariasis with unusual lesions in cattle from a dairy cattle farm in the city of Boa Vista do Buricá, RS, Brazil, as well as to demonstrate an alternative method for the diagnosis of the disease. Cases: We prospectively evaluated 15 Holstein cows, aged between 1 and 10-year-old whose data and materials for diagnosis, were provided by the property owner. The outbreak occurred in the summer, in a period of greater rainfall, affecting cows of different ages and totaling 48% of the herd. These showed ulcerative lesions on the skin of the groin, limbs and interdigital regions, and less frequently in the udder. The samples were obtained through tissue biopsy and scraped from the lesions, being packed in 10% formaldehyde for fixation. Afterward, the formaldehyde was centrifuged at 800 g for 5 min, which consisted of analyzing the sediment through optical microscopy and without staining, aiming at the direct search of the agent. The tissues, on the other hand, underwent routine processing and stained with Hematoxylin and Eosin. Histopathological analysis did not reveal Stephanofilaria sp. subjects in morphological analysis and revealed acanthosis, spongiosis, ulcers and fibrosis in the analyzed tissue. The examination of direct research with formaldehyde proved to be efficient, and fast. In the direct examination of the agent, structures similar to filarial and compatible with Stephanofilaria sp. in all samples. Thus, the present study demonstrated that filariasis can present in the form of outbreaks and with unusual injuries. The examination of direct research with formaldehyde, proved to be efficient and fast. Discussion: Semi-confined and confined animals may have a higher occurrence of strephanofilariasis, since the parasite needs humid and warm environments to proliferate and that, the proliferation of stephanophilariasis vectors is intensified in environments with low sunlight, high temperatures, high humidity, and low cleaning frequency. The city of Boa Vista do Buricá, where the outbreak occurred, reached a minimum average temperature of 18.5ºC and an average of 29ºC, with an average rainfall of 120.5 mm. Cutaneous lesions have been seen in animals from 1 to 10 years of age and no racial predisposition, age, or blackout stage is reported. The histological diagnosis, although mentioned as a form of diagnosis, has low efficacy in finding parasites in the tissue, is also used as a diagnosis, direct examination of the agent with saline solution, and impression of the lesion stained by the Romanoswsky method. However, in this report, formaldehyde proved to be a new option, as efficiently as saline.

Pesquisa qualitativa no contexto da Medicina Veterinária / Qualitative research in Veterinary Medicine

Em saúde animal, ainda são poucos os estudos com ênfase na pesquisa qualitativa, o que reduz a capacidade de compreensão do processo saúde/doença sob a ótica dos atores sociais envolvidos na produção familiar, dificultando assim a construção de propostas para a elaboração de modelos mais eficientes de atenção à saúde animal e uma consequente melhoria dos níveis de produtividade e qualidade de vida no campo. Assim, torna-se necessário incrementar estudos epidemiológicos com abordagens qualitativas em Medicina Veterinária, visando uma análise mais ampla e minuciosa da realidade não quantificável da cadeia produtiva como um todo, ou seja, visando identificar o universo de significados, motivos, aspirações, crenças, paradigmas, dificuldades, necessidades, valores e atitudes dos proprietários, assim como aqueles dos profissionais da área de saúde animal que os assistem. O presente trabalho teve como objetivo a revisão do referencial teórico e a problematização desse tema, engendrando a construção histórica do paradigma científico em epidemiologia e sua complementaridade com a abordagem qualitativa, visando contribuir para o avanço de um processo transdisciplinar, ao perceber os processos de saúde/doença animal a partir de um novo paradigma.

In animal health, there are still few studies with emphasis on qualitative research, which reduces the capacity to understand the health/disease process from the perspective of the social actors involved in family production, making it difficult to construct proposals for the elaboration of more efficient models of health in attention to animal health and a consequent improvement in levels of productivity and quality of life in the field. Thus, it is necessary to increase epidemiological studies with qualitative approaches in veterinary medicine, aiming at a broader and more detailed analysis of the non-quantifiable reality of the production chain as a whole, that is, aiming to identify the universe of meanings, motives, aspirations, beliefs, paradigms, difficulties, needs, values and attitudes of the owners, as well as those of the animal health professionals who assist them. This study aimed to review the theoretical framework and discuss this topic, engendering the historical construction of the scientific paradigm in epidemiology and its complementarity with the qualitative approach, in order to the contribute to the advancement of a transdisciplinary process, by understanding the health processes /animal disease from a new paradigm.

Breed and heterosis effects on reproduction and production traits of Girolando cows

The objective of this study was to evaluate the breed and heterosis effects on reproductive traits, test-day milk yield, and 305-day milk yield in different lactations of crossbred Girolando cows. Data consisted of test-day milk yield records of first (118,831 records), second (63,227), and third lactation (44,512) and their relative productive (test-day milk yield, 305-day milk yield, and lactation length) and reproductive (age at first calving, calving interval, days open, and dry period) records of 35,582 Girolando cows from Brazil, collected from 1998 to 2014. The heterosis effect of the evaluated traits in Girolando cattle was estimated by MIXED procedure in SAS. Girolando cows showed a negative (favorable) and significant heterosis effect for reproductive traits. The dry periods between the first and second calving and between the second and third calving showed the greatest gains in heterosis (21.93 and 10.41%, respectively). All the evaluated productive traits showed a significant and similar heterosis effect between the three lactations. The use of crossbreeding strategies between the Holstein and Gyr breeds, instead of using the pure breed, is indeed a good alternative to increase the economic efficiency of the dairy activity in the different production systems in tropical environments.(AU)

Genetic evaluation of oocyte and embryo production in dairy Gir cattle using repeatability and random regression models

The objective of this work is to estimate genetic parameters and breeding values to improve embryo and oocyte production, using repeatability and random regression models (RRM) for Gir dairy cattle. We used 11,398 records of ovum pick-up from 1,747 dairy Gir donors and evaluated sixteen different models: the traditional repeatability model and fifteen RRM, each of which considered a different combination of Legendre polynomial regressors to describe the additive genetic and permanent environment effects. The 4G1P model (four regressors for the genetic effect and one regressor for the permanent environment effect) is the most suitable model to analyze the number of viable and total oocytes, while the 3G1P is the best model to analyze the number of cleaved and viable embryos, according to the values of the Akaike information criterion (AIC) and the Bayesian information criterion (BIC). The heritability estimated with the RRM was higher than that estimated with the repeatability model. The high repeatability reported for oocyte and embryo count traits indicates that donors, which had high oocyte and embryo counts in the first ovum pick-up, should maintain this result in the next ovum pick-up. Genetic correlations between adjacent ages were high and positive, while genetic correlations between extreme ages were weak. We observed a reranking of the top sires and females (heifers and cows) over the period evaluated. The reliability of the estimated breeding values by RRM showed changes across age, and the expected genetic gains by RRM are larger. This shows that RRM is most suitable alternative for the evaluation and selection of oocyte and embryo count traits.(AU)

Prevalence and risk factors associated with anti-Leptospira spp agglutinins in cattle from dairy farmers in Ji-Paraná, RO, Brazil / Prevalência e fatores associados ao risco da presença de aglutininas anti-Leptospira spp em bovinos de agricultores familiares da bacia leiteira do município de Ji-Paraná - RO, Brasil

Leptospirosis affects several animal species, including man. This study aimed to evaluate the prevalence of Leptospira spp. and to identify factors associated with the risk of Leptospira spp. in dairy cattle in the municipality of Ji-Paraná, RO, Brazil, sampled by rural sector, from September 2012 to November 2013. Blood samples from 627 dairy cows were randomly collected from 63 farms belonging to six rural sectors. Leptospirosis was diagnosed by the microscopic serum agglutination technique. Of the 627 animals tested, 255 had anti-Leptospira antibodies (40.48%, 95% CI: 36.64-44.31) and 57 of the 63 studied dairy farms (90.5%, 95% CI: 83.23-97.72) had at least one reactive animal. The results indicate that serovar Hardjo had the highest (12.38%. 95% CI: 10.03-15.18) followed by serovars Shermani, Wolffi, Hebdomadis and Canicola occurrence in dairy cows. Additionally, infection was also associated with abortion occurrences in cows of 36 farms (57.14%) and the presence of dogs roaming free with access to pasture, water and cattle in 47 farms (74.60%). Therefore, free-roaming animals are considered a predisposing factor, highlighting the need for adopting prophylactic measures while raising the awareness from rural producers about the importance and the economic losses that leptospirosis may cause.

A leptospirose acomete diversas espécies animais, inclusive o homem. Este estudo teve como objetivo avaliar a prevalência de anticorpos contra Leptospira spp., bem como identificar fatores associados ao risco da infecção por Leptospira spp. em bovinos de leite do município de Ji-Paraná - RO, amostrados por setor rural, de setembro de 2012 a novembro de 2013. Amostras de sangue foram coletadas sistematicamente de 627 fêmeas leiteiras, oriundas de 63 propriedades pertencentes a seis setores rurais. O diagnóstico da leptospirose foi realizado por meio da soroaglutinação microscópica. Constatou-se que 255 animais possuíam anticorpos anti-Leptospira (40,48%, IC95%: 36,64-44,31). Das 63 propriedades estudadas, 57 (90,5%, IC95%: 83,23-97,72) apresentavam pelo menos um animal reagente. Observou-se maior ocorrência do sorovar Hardjo nas fêmeas bovinas (12,38%, IC95%: 10,03-15,18), seguido dos sorovares Shermani, Wolffi, Hebdomadis e Canicola. Observaram-se, como fatores associados à infecção por sorovar, a ocorrência de aborto em fêmeas de 36 propriedades estudadas (57,14%), bem como a existência de cães criados livres em 47 propriedades (74,60%) e com acesso ao pasto, à água e aos bovinos, o que reforça a necessidade de adoção de medidas profiláticas e a conscientização dos produtores rurais sobre a importância e os prejuízos que podem ser causados pela leptospirose.

An outbreak of systemic intoxication with irritant contact dermatitis due cypermethrin in dairy cows: case report / Surto de intoxicação sistêmica com dermatite de contato irritante devido à cipermetrina em vacas leiteiras: relato de caso

Pyrethroids are ectoparasiticides safe for mammals and widely used in farm animals. An outbreak of systemic intoxication with irritant contact dermatitis resulting from the use of cypermethrin pour on in dairy cows is reported in the state of Pernambuco. Eight adult animals were affected, three died on the property and five were referred to the Clínica de Bovinos, Universidade Federal Rural de Pernambuco, Campus Garanhuns. These received 100 mL of pour on Cypermethrin (Ectonil ®, Cipermetrina, Labgard, Brasil). Apathy, hyperexcitability, muscle tremors, sialorrhea, bradycardia and crusted lesions were observed on the dorsum of the neck, scapula, ears and ulcerations in the oral and vaginal mucosa. There was hyperfibrinogenemia and leukocytosis due to neutrophilia with a regenerative left shift. Histopathology showed areas of erosion and ulceration of the epidermis and perivascular lymphohistiocytic and neutrophilic infiltrate in the superficial dermis. Supportive treatment was done with improvement of systemic signs and skin lesions, however, in one animal (with 19 days hospitalized), there was no complete regression of neurological alterations of bradycardia and muscle tremors, even so, it was possible to return to productive activity. High doses of pour on cypermethrin may cause systemic intoxication in cattle and result in bradycardia, hyperexcitability, muscle tremors and sialorrhea with irritant contact dermatitis, and death in severe cases.

Os piretroides são ectoparasiticidas com grande segurança para mamíferos, utilizados amplamente em animais de produção. Relata-se um surto de intoxicação sistêmica com dermatite irritante por contato, resultante do uso de Cipermetrina Pour-On em bovinos, no estado de Pernambuco. Oito animais adultos foram acometidos: três deles morreram na propriedade e cinco foram recebidos na Clínica de Bovinos da Universidade Federal Rural de Pernambuco, Campus Garanhuns. Todos haviam recebido 100mL de Cipermetrina Pour-On (Ectonil®, Cipermetrina, Labgard, Brasil). Observou-se apatia, hiperexcitabilidade, tremores musculares, sialorreia, bradicardia e lesões crostosas no dorso da região de pescoço, na escápula, mas orelhas, bem como ulcerações em mucosa oral e vaginal. No hemograma, verificou-se hiperfibrinogenemia e leucocitose por neutrofilia com desvio à esquerda regenerativo. Na histopatologia, foram constatadas áreas de erosão e ulceração da epiderme e infiltrado linfo-histiocitário e neutrofílico perivascular na derme superficial. O tratamento de suporte gerou melhora dos sinais sistêmicos e das lesões cutâneas, porém, em um dos animais (que esteve internado por 19 dias), não houve regressão completa das alterações neurológicas de bradicardia e de tremores musculares; mesmo assim, foi possível o retorno à atividade produtiva. Doses elevadas de Cipermetrina Pour-On podem causar intoxicação sistêmica em bovinos e resultarem em bradicardia, hiperexcitabilidade, tremores musculares e sialorreia com dermatite irritante por contato, bem como morte em casos severos.

Effect of milk production scale on the economic return of dairy farmers in the Triângulo Mineiro/Alto Paranaíba mesoregion / Efeito da escala de produção de leite na rentabilidade de pecuaristas leiteiros da mesorregião do Triâgulo Mineiro e Alto Paranaíba

This study proposes to evaluate the relationship between the economic return of dairy production and its scales. Economic and production data were collected from 28 dairy farms located in the Triângulo Mineiro/Alto Paranaíba mesoregion, MG, Brazil. The farms were stratified into three scales of milk production: small (less than 150 kg), medium (151 to 400 kg), and large (over 400 kg). Data collected between January and December 2013 were analyzed statistically using SPSS 27.0 software, considering a minimum significance level of 95% (P < 0.05). Gross Margin, Net Margin, and Outcome were used as indicators of return. Among the fixed costs, depreciation corresponded to 16.56, 15.90, and 12.54% of total costs for the small, medium, and large producers, respectively. Among the variable costs, feeding accounted for 26.26, 34.94, and 44.58% of total costs on the small, medium, and large farms, respectively. Only the large-scale producers had positive outcomes (BRL 27,010.73), whereas the small and medium producers had losses (BRL -28,615.21 and BRL -18,233.83, respectively). In conclusion, increasing the scale of production positively influences the economic return of dairy farming.(AU)

Objetivou-se avaliar a relação entre a rentabilidade da atividade leiteira e suas escalas de produção. Para isso, foram levantados dados econômicos e produtivos de 28 propriedades leiteiras localizadas na mesorregião do Triângulo Mineiro/Alto Paranaíba, MG. As propriedades leiteiras foram estratificadas em três escalas de produção: pequena (inferior a 150 kg), média (entre 151 a 400kg) e grande (acima de 400 kg). Os dados coletados entre janeiro a dezembro de 2013 foram analisados estatisticamente através do software SPSS 27.0, considerando-se nível mínimo de significância de 95% (P < 0,05). Foram utilizados como indicadores de rentabilidade a Margem Bruta, a Margem Líquida e o Resultado. Dentre os custos fixos, a depreciação correspondeu a 16,56%, 15,90% e 12,54% dos custos totais para pequenos, médios e grandes produtores, respectivamente. Dentre os custos variáveis, a alimentação representou 26,26%, 34,94% e 44,58% dos custos totais para pequenos, médios e grandes produtores, respectivamente. Somente os grandes produtores apresentaram resultados positivos (R$27.010,73), enquanto que os pequenos e médios produtores obtiveram prejuízos (-R$28.615,21 e -R$18.233,83, respectivamente). Conclui-se que o aumento da escala de produção influencia positivamente a rentabilidade da pecuária leiteira.(AU)

Influence of the seasons on the quality and composition of milk from dairy farms in the northern region of Rio Grande do Sul, Brazil / Influência das estações do ano sobre a qualidade microbiológica do leite de fazendas leiteiras da região norte do Rio Grande do Sul, Brasil

This study aimed to verify the relationship between parameters of physicochemical composition, microbiological quality, and volume of milk delivered to a dairy in the northern region of Rio Grande do Sul, Brazil, at four different times in 2020. For this purpose, the parameters volume, protein, fat, lactose, total solids, somatic cell count (SCC), and standard plate count (SPC) were evaluated. The data were collected in January, April, July, and October from 1634 dairy farms located in the northern region of Rio Grande do Sul. The data were evaluated using Pearson's correlation, while the means were compared using Tukey's test, both at a 5% significance. Milk fat and protein contents were higher during fall (4.02 and 3.35%) and winter (3.90 and 3.36%, respectively), contributing to a higher concentration of solids. The microbiological quality of milk, especially SCC, is compromised during the warmer months due to the thermal stress suffered by the animals, challenging their immune system and increasing their susceptibility to diseases. The highest milk SPC in the winter (247.12 CFU/mL) refers to the transfer of contamination from the teat to the tank due to the inefficiency of pre-milking procedures. Therefore, the microbiological quality of milk was variable between the studied periods, and fat and protein contents suffered reductions during the summer, reflecting lower remuneration for quality given the high SCC in the same season.

O objetivo desse estudo foi verificar a relação entre parâmetros da composição físico-química, qualidade microbiológica e volume de leite entregue a um laticínio na região Norte do Rio Grande do Sul, no ano de 2020, em quatro diferentes épocas do ano. Para isso, foram avaliados os parâmetros volume, proteína, gordura, lactose, sólidos totais, contagem de células somáticas (CCS) e contagem padrão em placas (CPP). Os dados foram coletados nos meses de janeiro, abril, julho e outubro, em 1634 propriedades leiteiras localizadas na região Norte do Rio Grande do Sul. Os dados foram avaliados por meio da correlação de Pearson e as médias foram comparadas pelo teste de Tukey, ambos a 5% de significância. Os teores de gordura e proteína do leite foram maiores durante o outono (4,02 e 3,35%) e o inverno (3,90 e 3,36%, respectivamente), contribuindo para a maior concentração de sólidos no mesmo período. A qualidade microbiológica do leite, principalmente a CCS, é comprometida durante os meses mais quentes, em virtude do estresse térmico sofrido pelos animais, desafiando o sistema imune e aumentando a susceptibilidade a enfermidades. A maior CPP do leite no período de inverno (247,12 UFC/mL) remete à transferência de sujidades do teto para o tanque, em virtude da ineficiência dos procedimentos pré-ordenha. Portanto, a qualidade microbiológica do leite foi variável entre os períodos estudados, sendo que os teores de gordura e proteína sofreram reduções durante o verão, refletindo em menores remunerações por qualidade, visto a alta CCS na mesma estação.

Productive and reproductive performance of crossbred dairy heifers with induced lactation and efficacy of antimicrobial therapy associated with internal teat sealants / Desempenho produtivo e reprodutivo de novilhas com lactação induzida e eficácia da terapia antimicrobiana associada com selante interno de tetos

This study evaluated (a) the efficacy of an association between injectable antibiotic therapy and sealant (ATBS) on milk yield (MY), somatic cell count (SCC), and prevalence of intramammary infections (IMI); and (b) the efficacy of gonadotropin-releasing hormone (GnRH) on follicular cyst (FCs) resolution (cyclicity at the 45th day in milk; DIM) and cumulative pregnancy rate (CPR) in heifers submitted to a lactation induction protocol (LIP). A total of 114 crossbred (Holstein × Jersey) heifers, with 34.7 ± 4.8 months and 439 ± 56.35 kg were submitted to LIP. On the 5th day of the LIP, the heifers were assigned to (i) ATBS (n = 57) with 7 mg/kg of norfloxacin associated with sealant and (ii) Control 1 (n = 57; CONT1) with no treatments. Lactation began on the 21st day of LIP and the 15th DIM, FCs were diagnosed and 106 heifers were randomized into two treatment groups with 53 heifers each: (i) GnRH (5 mL injectable GnRH) and (ii) Control 2 (CONT2; no treatment). Of the 114 heifers initially induced, 83.33% (n = 95) responded to LIP with an average MY of 15.19 kg/milk/day during 22 weeks of lactation. In the first 14 DIM, the IMI prevalence was 18% and 28% for heifers ATBS and CONT1 treated, respectively. Additionally, coagulase-negative Staphylococcus was the most frequently isolated group of pathogens. Mammary quarters that received ATBS treatment had a lower risk of IMI and SCC than CONT1. The cyclicity at 45 DIM was 68% (ATBS) and 35% (CONT1), and 57% and 46% for animals in the GnRH and CONT2. CPR was 60% in the ATBS group and 89% in CONT1, but GnRH treatment did not affect the CPR. In conclusion, LIP was effective in stimulating MY in heifers, and the IMI prevalence decreased with ATBS treatment. Also, the use of GnRH did not affect the FC regression, cyclicity at 45 DIM, and CPR.(AU)

Este estudo avaliou a (i) eficácia da associação entre antibioticoterapia injetável e selante interno de tetos (ATBS) na produção de leite (PL), contagem de células somáticas (CCS), e prevalência de infecções intramamárias (IIM); e (ii) eficácia do hormônio liberador de gonadotrofina (GnRH) na resolução de cistos foliculares (CFs), ciclicidade ao 45º dia em lactação (DEL) e taxa de prenhez cumulativa (TPC) em novilhas submetidas a um protocolo de indução de lactação (PIL). Um total de 114 novilhas mestiças (Holandês × Jersey), com 34,7 ± 4,8 meses e 439 ± 56,35 kg foram submetidas ao PIL. No 5º dia do PIL, as novilhas receberam: (i) ATBS (n = 57) com 7 mg/kg de norfloxacina associada ao selante interno de tetos e (ii) Controle 1 (n = 57; CONT1) sem tratamento. A lactação teve início no 21º dia do PIL e no 15º DEL, foram diagnosticados CFs e 106 novilhas foram agrupadas em dois grupos de tratamento com 53 novilhas em cada: (i) GnRH (5 mL de GnRH injetável) e (ii) Controle 2 (CONT2; sem tratamento). Das 114 novilhas inicialmente induzidas, 83,33% (n = 95) responderam ao PIL com PL média de 15,19 kg/leite/d durante 22 semanas de lactação. Nos primeiros 14 DEL a prevalência de IIM foi de 18% e 28% para as novilhas tratadas com ATBS e CONT1, respectivamente. Além disso, estafilococos coagulase negativa foram o grupo de patógenos mais frequentemente isolados. Quartos mamários tratados com ATBS tiveram menor risco (0,56) de IIM e menor CCS do que CONT1. A ciclicidade a 45 DEL foi de 68% (ATBS) e 35% (CONT1), e 57% e 46% para os animais no GnRH e CONT2. A TPC foi de 60% no grupo ATBS e 89% no CONT1, porém o tratamento com GnRH não afetou a TPC. Em conclusão, o PIL foi eficaz em estimular a PL em novilhas tardias e a prevalência de IIM diminiuiu com o tratamento ATBS. Além disso, o uso de GnRH não afetou a regressão de CF, ciclicidade em 45 DEL e a TPC.(AU)

Bull-bull mounts in Holstein bulls: a survey of its incidence, possible causes, and consequences in Uruguayan bull' breeders

Abstract Bulls frequently display male-male mounts, with consequences in the incidence of injuries, and possibly affecting the reproductive performance of the bulls. This behavior is known as the "buller syndrome" when appears in steers, with several individuals mounting one or a few penmates. The study aimed to collect information on the incidence of bull-bull mounts, the possible associated factors, the productive consequences, and management applied by distributing a survey to Holstein bull breeders in Uruguay. A survey was applied and responded by most Holstein breeders in Uruguay (30/33). Nineteen of the 30 breeders observed mounting behavior among bulls, and 15 of them considered it as a relevant problem. The breeders that observed the behavior had a greater number of bulls than those that did not observe it (P = 0.002). All of them observed that mounts were persistently directed towards the same individual (considering a specific period, while it remained in the group). Of these, 11 (58%) considered that this stopped only when the "buller" bull was removed from the group, mentioning that the behavior was frequently redirected to another individual. The mounts between bulls are a major problem in the breeding of Holstein bulls, with important consequences on weight gain and animal health, reproductive problems such as low libido and seminal quality, and even provoking the death of animals. Although not all breeders reported the existence of the problem, those with the bigger herds did. While some management and/or environmental conditions seem to influence (higher density, regrouping, managements that involve movement of animals, and spring) the incidence of bull-bull mounts, there are no standardized managements to avoid this behavior. Considering that most breeders were interested in including practices to minimize this problem if available, it would be essential to understand better the causes and predisposing factors to decrease its negative impacts.

Milking practices on commercial Holstein-Friesian farms

The objective of this study was to survey and analyze milking practices of commercial Holstein-Friesian farms. A total of 43 Hungarian dairy farms with 31,430 cows was surveyed by using a questionnaire via personal interviews. Furthermore, seven in-depth, individual interviews were conducted with farm managers. In the statistical analysis, we used ANOVA models. The results showed that 57.8% of the milking parlors had a herringbone design, followed by parallel (20.0%) and rotary (17.8%) milking systems. For the interviewed farm managers, gentle (71.4%) and quick milking (57.1%) as well as herd size (57.1%) were the most important factors in determining the milking system design. In 62.8% of the farms, cows were milked twice a day, and the average milking time was 5.0 h with an average of 3.1 laborers. The average daily milking time per cow was 15 min and the average daily walking time per cow to the milking parlor and back was 24 min. Furthermore, 85.4% of the farms used traditional elastic milk liners, whereas 14.6% used silicone ones. In total, 57.1% of the interviewed farm managers said that the ideal teat liner should fit the teats correctly and provide gentle milking. Prior to milking, 65.1% of the farms used disinfectant dip and 11.6% used a disinfectant wash, whereas 23.3% still washed the udder with water. The udder was wiped with paper towels in 73.8% of the herds and with cloth in 26.2% of the herds. Forestripping was performed in all herds: 51.2% onto the floor, 46.5% into a cup, and in 2.3% into a paper towel. Further, 85.7% of the interviewed farm managers considered the use of a cup to be the ideal method, but 57.1% deemed a dark-colored piece of rubber/flooring to be similarly acceptable. Cows with mastitis were milked separately in 91.9% of the farms.

Breed, heterosis, and recombination effects for lactation curves in Brazilian cattle

The objective of this study was to estimate the breed, heterosis, and recombination effects on different components of the lactation curve of Girolando cattle. The dataset used consisted of 12,121 purebred cows of Holstein (H) and Gyr (G) breeds, and six H×G crossbred cows (Girolando). The model used presents random effects of herd and cow, regression coefficient associated with linear effect of proportion of H breed, regression coefficient associated with the linear effect of heterosis between H and G breeds, regression coefficient associated with the linear effect of recombination between H and G breeds, and random effect of residual. Dijkstra's (DJ), Nelder's (ND), Wilmink's (WL), and Wood's (WD) models were tested to fit production records of these different genetic groups. These models were then tested according to evaluation criteria of quality of fit (AIC, BIC, and RMSE), and the two best models (WD and WL) were chosen for estimation of 305-day milk yield (MY305), peak yield, time to peak, and persistency of milk yield. The breed effect was significant for all traits and components of the lactation curve. The heterosis effect was significant for all traits, and was more significant for MY305 (945.62±79.17 kg). Peak yield was the component of lactation curve that presented the most significant heterosis effect, partially explaining the heterosis effect (12 to 21%) found for MY305. The recombination effect was positive only for lactation period and time to peak of lactation in Girolando cows.

Accuracy and physical characteristics of total mixed rations and feeding sorting behavior in dairy herds of Castro, Parana

The objective of this study was to assess the accuracy of the content of total mixed rations (TMR) offered to high-producing cows from 20 dairy herds of Castro, Paraná State, Brazil. The average milk yield during the sample collection period was 38.0±6.8 kg/day, with 3.47±0.25% milk fat and 3.05±0.18% milk protein. The particle size distribution of samples of fresh diet and leftovers was evaluated using the Penn State Particle Separator (PSPS) and chemical analysis was also conducted. The TMR homogeneity was estimated by the coefficient of variation (CV) of particles retained on the two intermediary sieves (1.18 mm), in which a CV higher than 5% indicated a poorly mixed TMR. The TMR offered exceeded the formulated TMR only for NDF (+7.3%) and was lower than the formulated TMR for CP (−6.5%), ADF (−10.1%), and ash (−18.6%) contents. These differences are due to daily variations in feed quality, mixing equipment, and ingredient mixing order, mostly for forage. Differences between leftovers and TMR offered were substantial: −9.4% for CP, +25.1% for NDF, +31.6% for ADF, and +13.1% for ash, suggesting a feed sorting effect against long forage particles and in favor of small concentrate particles. The proportion of the offered TMR retained in the top PSPS sieve showed positive correlations with NDF (r = 0.58) and ADF (r = 0.54) contents of the refusals, which indicates that cows sort against long particles. Positive correlations were also found between the CV in the second sieve and NDF (r = 0.56) and ADF (r = 0.47) contents of refusals, suggesting that poorly mixed diets are more easily sorted by cows. Therefore, evaluating the chemical and physical properties of TMR, especially for forage, is extremely important for providing a consistent diet.