Association between chronic Anaplasma marginale and Babesia spp. infection and hematological parameters of taurine heifers / Associação entre infecção crônica por Anaplasma marginale e Babesia spp. e parâmetros hematológicos de novilhas taurinas

The aim of this study was to investigate the association between chronic Anaplasma marginale and Babesia spp. infection and hematological parameters of pregnant and non-pregnant taurine heifers. Blood samples from 94 females were collected on the first day (D-10) of timed artificial insemination (TAI) protocol and on pregnancy diagnosis (D+34). Hematological parameters were determined and compared between pregnant (PG) and non-pregnant (NPG) heifers, and within group at different sampling days. Real-time PCR (qPCR) was used to determine A. marginale and Babesia bovis infection, and for absolute quantification of Babesia spp. between PG and NPG groups. Correlation analysis was performed between the number of gDNA copies (CN) of Babesia spp. and hematological parameters. On D-10, mean hemoglobin concentration was higher for NPG, and hematocrit and total plasma protein were higher on D+34 for both groups. There was no difference in Babesia spp. CN between groups. In the first qPCR, all heifers were positive for A. marginale and B. bovis. Significant correlations were found between hemoglobin and erythrocyte and between hemoglobin and hematocrit (r = 0.8082 and r = 0.3009, respectively). Low levels of A. marginale and Babesia spp. did not affect hematological parameters of chronically infected pregnant and non-pregnant taurine heifers.(AU)

O objetivo deste estudo foi investigar a associação entre infecção crônica por Anaplasma marginale e Babesia spp. e parâmetros hematológicos de novilhas taurinas prenhes e não prenhes. Sangue de 94 fêmeas foi coletado no primeiro dia (D-10) do protocolo de inseminação artificial em tempo fixo (IATF) e no diagnóstico de gestação (D+34). Parâmetros hematológicos foram comparados entre novilhas prenhes (PG) e não prenhes (NPG) e dentro dos grupos entre dias de coleta. Usando-se PCR em tempo real (qPCR), determinou-se a infecção por A. marginale e Babesia bovis e quantificação absoluta de Babesia spp. Entre os grupos PG e NPG. A análise de correlação foi realizada entre o número de cópias (CN) de Babesia spp. e parâmetros hematológicos. No D-10, a concentração de hemoglobina foi maior para NPG e hematócrito, e proteína plasmática total foram maiores em D+34 para ambos os grupos. Não houve diferença para CN de Babesia spp. entre os grupos. Na primeira qPCR, todas as novilhas foram positivas para A. marginale e B. bovis. Correlações significativas foram encontradas entre hemoglobina/eritrócito e hemoglobina/hematócrito (r=0,8082 e r=0,3009, respectivamente). Baixos níveis de A. marginale e Babesia spp. não afetaram os parâmetros hematológicos de novilhas taurinas prenhes e não prenhes cronicamente infectadas.(AU)

Induction of lactation: an economic study of tool for dairy heifers with successive reproductive failures / Indução de lactação: levantamento econômico da utilização desta ferramenta em novilhas leiteiras com sucessivas falhas reprodutivas

The aim of this study was to evaluate the economic viability of the use of a lactation induction protocol in Holstein heifers. Were collected data of nutritional, reproductive and sanitary management pre and post-lactation period from 30 induction heifers (IG) and 30 pregnant heifers (CG). All animals were inseminated around 14 months of age and started lactation at 23±4 months. The animals of IG were heifers do not pregnant after two inseminations and natural service e were induced to lactation according to protocol: from the 1st to the 8th day, 30 mg of estradiol benzoate were administered daily, together with 300 mg of progesterone. From the 9th until the 14th, animals only received daily doses of 20 mg estradiol benzoate. On 16th day, 0.56 mg of sodium cloprostenol was administered and injections of 40 mg of dexamethasone sodium phosphate were administered daily from the 19th to the 21st day. On the 1st, 8th, 15th and 22nd day, the animals received a dose of sometribove zinc. The animals of CG were managed according to the farm routine. The costs of the CG during pre and post lactation (nutrition, sanitary, reproduction management) e were higher than the IG, however, when evaluating the economic viability due to lower milk production, the induced group did not leave profit in the first year of use. When comparing the lactation induction with the sale of animals that did not conceive and purchase of animals for replacement, this last scenario showed itself as a better alternative.

O objetivo deste estudo foi avaliar a viabilidade econômica do uso de um protocolo de indução a lactação em novilhas da raça Holandês. Foram coletados dados econômicos do manejo nutricional, reprodutivo e sanitário pré e pós lactação de 30 novilhas induzidas à lactação (IG) e 30 novilhas prenhes (CG). Todos os animais foram inseminados em torno de 14 meses de idade e iniciaram a lactação com aproximadamente 23±4 meses. Os animais do IG foram novilhas que não conceberam após duas inseminações e monta natural, e foram induzidas à lactação com o protocolo: do 1° ao 8° dia receberam aplicação de 30 mg de benzoato de estradiol juntamente com 300 mg de progesterona. A partir do 9° dia até o 14° receberam 20 mg de benzoato de estradiol. No dia 16 ocorreu uma aplicação de 0.56 mg cloprostenol sódico e nos dias 19 ao 21, de 40 mg de dexametasona. Nos dias 1, 8, 15, e 22, os animais receberam 500 mg somatotropina recombinante bovina. Os animais do CG foram manejados conforme a rotina da propriedade. Os custos do CG durante o pré e lactação (nutrição, sanidade, reprodução) foram superiores ao grupo induzido. No entanto, ao avaliar a viabilidade econômica, devido a menor produção leiteira, o grupo induzido não deixou lucro na propriedade no primeiro ano de utilização. Ao comparar a indução de lactação com a venda de animais que não conceberam e a compra de animais para reposição, este último cenário mostrou-se como uma melhor alternativa.

Endocrine profile and reproductive performance in heifers induced to lactation

Background: Low reproductive efficiency has been one of the main factors that lead to dairy herd culling in the reproductive age. In multiparous animals, such inefficiency and culling can occur because of various factors and may be associated with occasional endocrine failures. To avoid revenue losses that incur due to lack of lactation, lactation is artificiallyinduced in the animals that are not pregnant, using a defined protocol. The aim of this study was, therefore, to evaluateand compare the reproductive performance of heifers submitted to the induction protocol with that of pregnant heifersduring the transition period.Materials, Methods & Results: Sixty Holstein heifers, 32 ± 0.6 months of age, were divided into two groups: ControlGroup (Control, n = 30) comprising pregnant heifers that were accompanied since 21 days before the expected calvingdate until 224 days in milk (DIM) and an Induction Group (Induction, n = 30) comprising non-pregnant heifers submittedto a lactation induction protocol, accompanied from the beginning of the protocol until 224 DIM. For evaluation of theendocrine profile (progesterone and estradiol concentrations) of these animals, blood samples were collected at two periods: the pre-lactation (weeks -3, -2 and -1) and post-lactation (weeks 1 and 4). Heifers from both groups were submittedto weekly reproductive evaluations, from the beginning of lactation until 35 DIM. Uterine examinations were performedusing ultrasonography and vaginoscopy to evaluate uterine content, cervical opening, and mucosal aspect. Females ingood reproductive health were subjected to a hormonal protocol for timed artificial insemination (TAI). The pregnancyrate of heifers that could reproduce (Control, n = 13, and Induction, n = 20) were evaluated and inseminated until 49 DIM.Progesterone levels were similar (P > 0.05) in the two groups at both pre- and post-start of lactation. Estradiol...

Endocrine profile and reproductive performance in heifers induced to lactation

Background: Low reproductive efficiency has been one of the main factors that lead to dairy herd culling in the reproductive age. In multiparous animals, such inefficiency and culling can occur because of various factors and may be associated with occasional endocrine failures. To avoid revenue losses that incur due to lack of lactation, lactation is artificiallyinduced in the animals that are not pregnant, using a defined protocol. The aim of this study was, therefore, to evaluateand compare the reproductive performance of heifers submitted to the induction protocol with that of pregnant heifersduring the transition period.Materials, Methods & Results: Sixty Holstein heifers, 32 ± 0.6 months of age, were divided into two groups: ControlGroup (Control, n = 30) comprising pregnant heifers that were accompanied since 21 days before the expected calvingdate until 224 days in milk (DIM) and an Induction Group (Induction, n = 30) comprising non-pregnant heifers submittedto a lactation induction protocol, accompanied from the beginning of the protocol until 224 DIM. For evaluation of theendocrine profile (progesterone and estradiol concentrations) of these animals, blood samples were collected at two periods: the pre-lactation (weeks -3, -2 and -1) and post-lactation (weeks 1 and 4). Heifers from both groups were submittedto weekly reproductive evaluations, from the beginning of lactation until 35 DIM. Uterine examinations were performedusing ultrasonography and vaginoscopy to evaluate uterine content, cervical opening, and mucosal aspect. Females ingood reproductive health were subjected to a hormonal protocol for timed artificial insemination (TAI). The pregnancyrate of heifers that could reproduce (Control, n = 13, and Induction, n = 20) were evaluated and inseminated until 49 DIM.Progesterone levels were similar (P > 0.05) in the two groups at both pre- and post-start of lactation. Estradiol...(AU)

Induction of lactation: an economic study of tool for dairy heifers with successive reproductive failures / Indução de lactação: levantamento econômico da utilização desta ferramenta em novilhas leiteiras com sucessivas falhas reprodutivas

The aim of this study was to evaluate the economic viability of the use of a lactation induction protocol in Holstein heifers. Were collected data of nutritional, reproductive and sanitary management pre and post-lactation period from 30 induction heifers (IG) and 30 pregnant heifers (CG). All animals were inseminated around 14 months of age and started lactation at 23±4 months. The animals of IG were heifers do not pregnant after two inseminations and natural service e were induced to lactation according to protocol: from the 1st to the 8th day, 30 mg of estradiol benzoate were administered daily, together with 300 mg of progesterone. From the 9th until the 14th, animals only received daily doses of 20 mg estradiol benzoate. On 16th day, 0.56 mg of sodium cloprostenol was administered and injections of 40 mg of dexamethasone sodium phosphate were administered daily from the 19th to the 21st day. On the 1st, 8th, 15th and 22nd day, the animals received a dose of sometribove zinc. The animals of CG were managed according to the farm routine. The costs of the CG during pre and post lactation (nutrition, sanitary, reproduction management) e were higher than the IG, however, when evaluating the economic viability due to lower milk production, the induced group did not leave profit in the first year of use. When comparing the lactation induction with the sale of animals that did not conceive and purchase of animals for replacement, this last scenario showed itself as a better alternative.(AU)

O objetivo deste estudo foi avaliar a viabilidade econômica do uso de um protocolo de indução a lactação em novilhas da raça Holandês. Foram coletados dados econômicos do manejo nutricional, reprodutivo e sanitário pré e pós lactação de 30 novilhas induzidas à lactação (IG) e 30 novilhas prenhes (CG). Todos os animais foram inseminados em torno de 14 meses de idade e iniciaram a lactação com aproximadamente 23±4 meses. Os animais do IG foram novilhas que não conceberam após duas inseminações e monta natural, e foram induzidas à lactação com o protocolo: do 1° ao 8° dia receberam aplicação de 30 mg de benzoato de estradiol juntamente com 300 mg de progesterona. A partir do 9° dia até o 14° receberam 20 mg de benzoato de estradiol. No dia 16 ocorreu uma aplicação de 0.56 mg cloprostenol sódico e nos dias 19 ao 21, de 40 mg de dexametasona. Nos dias 1, 8, 15, e 22, os animais receberam 500 mg somatotropina recombinante bovina. Os animais do CG foram manejados conforme a rotina da propriedade. Os custos do CG durante o pré e lactação (nutrição, sanidade, reprodução) foram superiores ao grupo induzido. No entanto, ao avaliar a viabilidade econômica, devido a menor produção leiteira, o grupo induzido não deixou lucro na propriedade no primeiro ano de utilização. Ao comparar a indução de lactação com a venda de animais que não conceberam e a compra de animais para reposição, este último cenário mostrou-se como uma melhor alternativa.(AU)

Evaluation of follicular growth and progesterone production in Bos taurus cows strategically treated with insulin / Avaliação do crescimento folicular e da produção de progesterona em vacas Bos taurus tratadas estrategicamente com insulina

The goal of this study was to evaluate the effects of strategic insulin administration on follicular growth, progesterone production, and pregnancy rate in beef cattle. Two experiments were conducted, in experiment 1, 215 cows crossbreed cows (Bos indicus × Bos taurus) (Control Group, n = 109; Insulin Group, n = 106) were submitted to fixed-time artificial insemination (TAI) with application of 2 mg of estradiol benzoate and a vaginal device containing progesterone on day 0. On day 9, the device was removed and 0.5 mg of estradiol cypionate was administered with 12.5 mg of dinoprost and 0.25 UI kg-1 of insulin for the treated animals. On day 11, artificial insemination (AI) was performed on all animals. On days 9 and 11 according to the protocol, was evaluated follicular growth and estrus manifestation, and 30 days after AI the pregnancy rate. In experiment 2, 85 cows were utilized, including Aberdeen Angus, Hereford, and crossbreeds (Control Group, n = 49 and Insulin Group, n = 36), and were submitted to the protocol for fixed-time embryo transfer (FTET), and progesterone concentrations were evaluated. On day 0, the cows received 2 mg of estradiol benzoate and a vaginal device containing progesterone. On day 5 of the protocol, 0.150 mg of cloprostenol was administered. On day 8, the vaginal device was removed and 20 mg of purified porcine pituitary extract and 0.25 UI kg-1 of insulin was given to the animals in the treatment group, and on day 9, 1 mg of estradiol benzoate was administered. On day 17, an embryo transfer was performed and blood collection for evaluation of progesterone levels in animals submitted to FTET were collected. In experiment 1, the follicular growth rate and the pregnancy rate were similar between groups (P > 0.05) and in experiment 2, the production of P4 was not different between the animals that received the insulin application and the control group...

O objetivo deste estudo foi avaliar o efeito da aplicação estratégica de insulina sobre o crescimento folicular, produção de progesterona e taxa de prenhez em bovinos de corte. Foram realizados 2 experimentos, no experimento 1, 215 vacas cruzas (Bos indicus x Bos taurus) (Grupo Controle = 109; Grupo Insulina = 106) foram submetidas a um protocolo que consistiu na aplicação de 2 mg de benzoato de estradiol e inserção de um dispositivo intravaginal de liberação lenta de progesterona (P4) sendo este o dia zero do protocolo. No dia 9, foi realizada a remoção do dispositivo de P4, a aplicação de 0,5 mg de cipionato de estradiol, e 12,5 mg de dinoprost. Os animais do grupo insulina receberam ainda a aplicação de 0,25 UI kg-1 de insulina. No dia 11 foi realizada a inseminação artificial de todos os animais. Nos dias 9 e 11 de acordo com o protocolo, foi avaliado crescimento folicular e manifestação de estro, e 30 dias após IA foi avaliado a taxa de prenhez. O experimento 2 foi realizado com 85 vacas da raça Aberdeen Angus, Hereford e cruzas (Grupo Controle = 49; Grupo Insulina = 36) submetidas a um protocolo de Transferência de Embrião em Tempo Fixo (TETF). No dia 0 fez-se aplicação de 2 mg de benzoato de estradiol e a inserção de um dispositivo intravaginal de liberação lenta de progesterona. No 5º dia do protocolo foi aplicado 0,150 mg de d- Cloprostenol. No dia 8 fez-se a remoção do dispositivo de P4 e aplicação de 20 mg de foltropina de pituitária suína e de 0,25 UI kg-1 de insulina nos animais tratados e no dia 9 foi aplicado 1 mg de benzoato de estradiol. No dia 17 procedeu-se com a transferência dos embriões e coleta de sangue para avaliação dos níveis de progesterona nos animais submetidos a TETF. No experimento 1 a taxa de crescimento folicular e a taxa de prenhez foram semelhantes entre os grupos (P > 0,05) e no experimento 2 a produção de P4 não foi diferente entre os animais que receberam a aplicação de insulina e o grupo controle...

Evaluation of follicular growth and progesterone production in Bos taurus cows strategically treated with insulin / Avaliação do crescimento folicular e da produção de progesterona em vacas Bos taurus tratadas estrategicamente com insulina

The goal of this study was to evaluate the effects of strategic insulin administration on follicular growth, progesterone production, and pregnancy rate in beef cattle. Two experiments were conducted, in experiment 1, 215 cows crossbreed cows (Bos indicus × Bos taurus) (Control Group, n = 109; Insulin Group, n = 106) were submitted to fixed-time artificial insemination (TAI) with application of 2 mg of estradiol benzoate and a vaginal device containing progesterone on day 0. On day 9, the device was removed and 0.5 mg of estradiol cypionate was administered with 12.5 mg of dinoprost and 0.25 UI kg-1 of insulin for the treated animals. On day 11, artificial insemination (AI) was performed on all animals. On days 9 and 11 according to the protocol, was evaluated follicular growth and estrus manifestation, and 30 days after AI the pregnancy rate. In experiment 2, 85 cows were utilized, including Aberdeen Angus, Hereford, and crossbreeds (Control Group, n = 49 and Insulin Group, n = 36), and were submitted to the protocol for fixed-time embryo transfer (FTET), and progesterone concentrations were evaluated. On day 0, the cows received 2 mg of estradiol benzoate and a vaginal device containing progesterone. On day 5 of the protocol, 0.150 mg of cloprostenol was administered. On day 8, the vaginal device was removed and 20 mg of purified porcine pituitary extract and 0.25 UI kg-1 of insulin was given to the animals in the treatment group, and on day 9, 1 mg of estradiol benzoate was administered. On day 17, an embryo transfer was performed and blood collection for evaluation of progesterone levels in animals submitted to FTET were collected. In experiment 1, the follicular growth rate and the pregnancy rate were similar between groups (P > 0.05) and in experiment 2, the production of P4 was not different between the animals that received the insulin application and the control group...(AU)

O objetivo deste estudo foi avaliar o efeito da aplicação estratégica de insulina sobre o crescimento folicular, produção de progesterona e taxa de prenhez em bovinos de corte. Foram realizados 2 experimentos, no experimento 1, 215 vacas cruzas (Bos indicus x Bos taurus) (Grupo Controle = 109; Grupo Insulina = 106) foram submetidas a um protocolo que consistiu na aplicação de 2 mg de benzoato de estradiol e inserção de um dispositivo intravaginal de liberação lenta de progesterona (P4) sendo este o dia zero do protocolo. No dia 9, foi realizada a remoção do dispositivo de P4, a aplicação de 0,5 mg de cipionato de estradiol, e 12,5 mg de dinoprost. Os animais do grupo insulina receberam ainda a aplicação de 0,25 UI kg-1 de insulina. No dia 11 foi realizada a inseminação artificial de todos os animais. Nos dias 9 e 11 de acordo com o protocolo, foi avaliado crescimento folicular e manifestação de estro, e 30 dias após IA foi avaliado a taxa de prenhez. O experimento 2 foi realizado com 85 vacas da raça Aberdeen Angus, Hereford e cruzas (Grupo Controle = 49; Grupo Insulina = 36) submetidas a um protocolo de Transferência de Embrião em Tempo Fixo (TETF). No dia 0 fez-se aplicação de 2 mg de benzoato de estradiol e a inserção de um dispositivo intravaginal de liberação lenta de progesterona. No 5º dia do protocolo foi aplicado 0,150 mg de d- Cloprostenol. No dia 8 fez-se a remoção do dispositivo de P4 e aplicação de 20 mg de foltropina de pituitária suína e de 0,25 UI kg-1 de insulina nos animais tratados e no dia 9 foi aplicado 1 mg de benzoato de estradiol. No dia 17 procedeu-se com a transferência dos embriões e coleta de sangue para avaliação dos níveis de progesterona nos animais submetidos a TETF. No experimento 1 a taxa de crescimento folicular e a taxa de prenhez foram semelhantes entre os grupos (P > 0,05) e no experimento 2 a produção de P4 não foi diferente entre os animais que receberam a aplicação de insulina e o grupo controle...(AU)

Distal bone lesions diagnosed by radiographic examination in dairy cows without claudication

Background: During decades, dairy cows have been selected for its productive character, with the main focus on the breeding production, being submitted to constant conditions of metabolic disorders, likewise submitted to permanent or intermittent episodes of systemic and / or mechanical aggression, anatomofunctional of its orthopedic system, appearing locomotion injuries. The present approach brings up the variable aspect of lesions in the extensor process of the third phalanx bone, diagnosed by digital radiography, in 17 Holstein cows, with or without joint involvement, the study was conducted in a commercial farm located in the South of Rio Grande do Sul State, Brazil.Case: This case report describes the identification and the appearance of lesions on the extensor process of the third phalanx bone in dairy cattle from a commercial herd. 17 Holstein cows with three lactations, with average production in two milking of 30.67 ± 5.39 L of milk submitted to semi-extensive system, with daily walk of 2.2 km between pasture, food and milking parlor. Weekly, the cows were submitted to clinical diagnosis and radiological exploration, on two periods (pre- and postpartum), from 14 days prepartum to 50 days postpartum. All animals despite the zero score of locomotion, demonstrated no abnormalities of posture or walking, however expressed at least one radiographic change in at least one member. Thereafter, radiographic lesions were evaluated for their variety and severity, indeed animals that had only injury extensor process, with fracture and / or joint involvement were detected. In the animals evaluated in this study there was antecedent clinical record of macroscopic lesions to the digit, without lameness.[...](AU)

Effects of the bull on conception rate of dairy cows in different seasons and according to AI type

Background: Reproductive efficiency is one of the most important factors affecting the performance dairy cattle, and fixedtime artificial insemination (TAI) is an important biotechnology factor employed in bovine livestock. The achievement of satisfactory results in TAI protocols depends of several factors, such as health and body condition, milk yield, environmental temperatures, ovulation time, semen manipulation, as well as semen quality. The goal of this study was to evaluate the conception rate of heifers and multiparous cows based on different Holstein bulls used for artificial insemination (AI). The effects of the type of management AI, animal category, and season of the year were also examined.Materials, Methods & Results: A three-year database on the reproductive management of a dairy farm was formed. All the cows and heifers were of the Holstein breed, in semi-intensive nutritional management, milked twice a day, and received a total mix ration. After 45 days in milk, when cows were observed twice daily with estrus signs, posterior artificial insemination occurred 12 h after estrus visualization was made. However, cows that were not observed in estrus were submitted to a timed artificial insemination (TAI). In this study, these fixed factors were considered: bulls utilized for the AI (totalizing 10 animals with at least 100 inseminations in each season, denoted by the letter B and a number - B1, B2, B3, B4, B5, B6, B7, B8, B9, B10); the season of the insemination (spring/summer being from November to April and autumn/winter from May to October), category animal (heifers, animals that never have been calved, or multiparous, animals that have already given birth more than once), and the type of AI (which included TAI using a protocol for synchronization, but cows having not necessarily shown estrus signs at the AI; ETAI: using protocol of synchronization, cows showing estrus signs at the AI;[...]

Distal bone lesions diagnosed by radiographic examination in dairy cows without claudication

Background: During decades, dairy cows have been selected for its productive character, with the main focus on the breeding production, being submitted to constant conditions of metabolic disorders, likewise submitted to permanent or intermittent episodes of systemic and / or mechanical aggression, anatomofunctional of its orthopedic system, appearing locomotion injuries. The present approach brings up the variable aspect of lesions in the extensor process of the third phalanx bone, diagnosed by digital radiography, in 17 Holstein cows, with or without joint involvement, the study was conducted in a commercial farm located in the South of Rio Grande do Sul State, Brazil.Case: This case report describes the identification and the appearance of lesions on the extensor process of the third phalanx bone in dairy cattle from a commercial herd. 17 Holstein cows with three lactations, with average production in two milking of 30.67 ± 5.39 L of milk submitted to semi-extensive system, with daily walk of 2.2 km between pasture, food and milking parlor. Weekly, the cows were submitted to clinical diagnosis and radiological exploration, on two periods (pre- and postpartum), from 14 days prepartum to 50 days postpartum. All animals despite the zero score of locomotion, demonstrated no abnormalities of posture or walking, however expressed at least one radiographic change in at least one member. Thereafter, radiographic lesions were evaluated for their variety and severity, indeed animals that had only injury extensor process, with fracture and / or joint involvement were detected. In the animals evaluated in this study there was antecedent clinical record of macroscopic lesions to the digit, without lameness.[...]

Effects of the bull on conception rate of dairy cows in different seasons and according to AI type

Background: Reproductive efficiency is one of the most important factors affecting the performance dairy cattle, and fixedtime artificial insemination (TAI) is an important biotechnology factor employed in bovine livestock. The achievement of satisfactory results in TAI protocols depends of several factors, such as health and body condition, milk yield, environmental temperatures, ovulation time, semen manipulation, as well as semen quality. The goal of this study was to evaluate the conception rate of heifers and multiparous cows based on different Holstein bulls used for artificial insemination (AI). The effects of the type of management AI, animal category, and season of the year were also examined.Materials, Methods & Results: A three-year database on the reproductive management of a dairy farm was formed. All the cows and heifers were of the Holstein breed, in semi-intensive nutritional management, milked twice a day, and received a total mix ration. After 45 days in milk, when cows were observed twice daily with estrus signs, posterior artificial insemination occurred 12 h after estrus visualization was made. However, cows that were not observed in estrus were submitted to a timed artificial insemination (TAI). In this study, these fixed factors were considered: bulls utilized for the AI (totalizing 10 animals with at least 100 inseminations in each season, denoted by the letter B and a number - B1, B2, B3, B4, B5, B6, B7, B8, B9, B10); the season of the insemination (spring/summer being from November to April and autumn/winter from May to October), category animal (heifers, animals that never have been calved, or multiparous, animals that have already given birth more than once), and the type of AI (which included TAI using a protocol for synchronization, but cows having not necessarily shown estrus signs at the AI; ETAI: using protocol of synchronization, cows showing estrus signs at the AI;[...](AU)

Concentration of minerals in the hoof horny capsule of healthy and lame dairy cows / Concentração de minerais no estojo córneo do casco em vacas leiteiras sadias e com claudicação

The aim of this study was to evaluate the mineral concentrations in the hoof horny capsule of healthy Holstein cows and cows with hoof problems associated with laminitis. Twenty-one multiparous Holstein cows with an average production of 24 L of milk/day, reared with semi-extensive nutritional management, were studied. The animals were evaluated and divided into two groups based on their locomotion score (LS, range: 0 to 4). LS greater than 2 indicated laminitis-associated lesions (lame cow group: LC), and LS = 0 indicated cows without laminitis (CWL). A sample of 30 mm2 was collected from the hoof horny capsule at the abaxial wall to evaluate the concentrations of calcium, phosphorus, zinc, and magnesium. Calcium blood concentration was also evaluated. The LC group had lower magnesium concentration (P=0.008) and showed a trend (P=0.06) for lower calcium concentration compared to healthy animals (CWL), even though all animals were normocalcemic. The concentration of other minerals did not differ between the LC and CWL group. In conclusion, the magnesium concentration in the hoof horny capsule was lower in cows with lesions associated with laminitis, while phosphorus and zinc concentrations were not affected. The relationship between hoof lesions and calcium concentration requires further investigation...(AU)

O objetivo deste trabalho foi avaliar as concentrações de minerais no tecido córneo de vacas leiteiras da raça Holandês saudáveis e com afecções podais associadas à laminite. Foram utilizados 21 bovinos, fêmeas, multíparas, da raça Holandês, com produção média de 24 litros de leite por dia, submetidas a manejo semi extensivo de alimentação. Os animais foram avaliados quanto ao seu escore de locomoção (EL) e divididos em dois grupos: EL acima de dois, apresentando lesões associadas à laminite (vacas com laminite - VCL); e EL igual a zero (vacas sem laminite - VSL). Foi realizada uma coleta de tecido córneo com aproximadamente 30 mm² de área da região abaxial da muralha do casco, a partir destas amostras foi realizada análise de cálcio, fósforo, zinco e magnésio. Foi realizada coleta de sangue para análise dos níveis de cálcio. Os animais do grupo VCL apresentaram níveis de magnésio menores (P=0,008), já com o cálcio foi observado aproximação da significância (P=0,06) para menores concentrações desse mineral quando comparado às vacas sadias (VSL) apesar de todos os animais serem normocalcêmicos. Os demais minerais avaliados não apresentaram diferença entre grupos. Em conclusão, vacas com lesões associadas à laminite apresentam menores concentrações de magnésio no tecido córneo digital, sem variação nas concentrações de fósforo e zinco. A relação entre lesões podais e os níveis de...(AU)

Concentration of minerals in the hoof horny capsule of healthy and lame dairy cows / Concentração de minerais no estojo córneo do casco em vacas leiteiras sadias e com claudicação

The aim of this study was to evaluate the mineral concentrations in the hoof horny capsule of healthy Holstein cows and cows with hoof problems associated with laminitis. Twenty-one multiparous Holstein cows with an average production of 24 L of milk/day, reared with semi-extensive nutritional management, were studied. The animals were evaluated and divided into two groups based on their locomotion score (LS, range: 0 to 4). LS greater than 2 indicated laminitis-associated lesions (lame cow group: LC), and LS = 0 indicated cows without laminitis (CWL). A sample of 30 mm2 was collected from the hoof horny capsule at the abaxial wall to evaluate the concentrations of calcium, phosphorus, zinc, and magnesium. Calcium blood concentration was also evaluated. The LC group had lower magnesium concentration (P=0.008) and showed a trend (P=0.06) for lower calcium concentration compared to healthy animals (CWL), even though all animals were normocalcemic. The concentration of other minerals did not differ between the LC and CWL group. In conclusion, the magnesium concentration in the hoof horny capsule was lower in cows with lesions associated with laminitis, while phosphorus and zinc concentrations were not affected. The relationship between hoof lesions and calcium concentration requires further investigation...

O objetivo deste trabalho foi avaliar as concentrações de minerais no tecido córneo de vacas leiteiras da raça Holandês saudáveis e com afecções podais associadas à laminite. Foram utilizados 21 bovinos, fêmeas, multíparas, da raça Holandês, com produção média de 24 litros de leite por dia, submetidas a manejo semi extensivo de alimentação. Os animais foram avaliados quanto ao seu escore de locomoção (EL) e divididos em dois grupos: EL acima de dois, apresentando lesões associadas à laminite (vacas com laminite - VCL); e EL igual a zero (vacas sem laminite - VSL). Foi realizada uma coleta de tecido córneo com aproximadamente 30 mm² de área da região abaxial da muralha do casco, a partir destas amostras foi realizada análise de cálcio, fósforo, zinco e magnésio. Foi realizada coleta de sangue para análise dos níveis de cálcio. Os animais do grupo VCL apresentaram níveis de magnésio menores (P=0,008), já com o cálcio foi observado aproximação da significância (P=0,06) para menores concentrações desse mineral quando comparado às vacas sadias (VSL) apesar de todos os animais serem normocalcêmicos. Os demais minerais avaliados não apresentaram diferença entre grupos. Em conclusão, vacas com lesões associadas à laminite apresentam menores concentrações de magnésio no tecido córneo digital, sem variação nas concentrações de fósforo e zinco. A relação entre lesões podais e os níveis de...