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RESUMO - Na conservação m vitro do capim-elefante foi observado que, ao longo dos subcultivos sucessivos de meristemas picais, ocorre gradual perda de vigor nas plântulas. Essa limitação torna necessária a reintrodução de acessos na coleção, comprometendo a eficiência do processo. Visando solucionar o problema, foi conduzido um estudo com 51 cultivares de capimelefante, onde, na repicagem efetuada a cada 4 a 6 meses, foram inoculados meristemas axilares da plântula, dispostos horizontalmente sobre meio MS, adicionado ou não de ácido naftalenoacético (ANA). Neste ciclo, que durou 45 dias, foram avaliadas as seguintes variáveis: número e comprimento dos explantes, gemas brotadas por explante, início e vigor da brotação, número de brotos desenvolvidos e percentagem de morte. Os resultados sugerem que esse método melhorou o vigor acentuadamente; embora as respostas, com e sem adição de ANA ao meio, tenham sido muito variadas entre cultivares. Apenas a cv. Mercker Comum Pinda não apresentou resposta satisfatória, devendo ser futuramente submetida a outras alternativas para propagação. Com base na produção de brotos, as cvs. Napier e Sem Pêlo apresentaram o melhor desempenho, na presença de ANA. O método mostrou-se promissor também pelo uso mínimo de reguladores do crescimento, reduzindo custos e a possibilidade de mutações. ABSTRACT - The continuous utiliwtion of explants obtainedfrom cultured apical meristems limits elephantgrass in vitro conservation because of gradual loss of vigor. Such a restriction makes it necessary to periodícally replace accessions in the coilection, reducing the efficiency of the technique. To overcome this problem, a study was carried out with 51 elephantgrass cultivars, where reculturing was conducted every 4 to 6 months using in vitro seediing axiliary meristems, with or without the addition of naphtaleneacetic acid (NAA) to the MS culture médium. During this reculturing cycle, which lasted 45 days, the following variables were evaluated: explant number and length, sprouted buds per explant, days to sprouting onset, sprouting vigor, number of developed shoots and percentage of death. The results suggest that the method improved seediing vigor markediy, altfwugh cultivar responses, regardiess of NAA addition, showed high variation. 'Mercker Comum Pinda' was the sole case showing no or weak response to either MS or NAA-enriched MS médium. Based on the number of sprouts developed, 'Napier' and 'Sem Pêlo' exhibited the best performance, when NAA was added to the médium. This method showed high potential to lower costs and reduce risks of mutations because of the limited utilization of growth regulators. Made available in DSpace on 2022-08-22T15:19:36Z (GMT). No. of bitstreams: 1 Conservacao-in-vitro-germoplasma-capim-elefante-micropropagacao-meristemas-axilares.pdf: 3008546 bytes, checksum: de8605dfc7b12dd3f83db9eb2a91e22a (MD5) Previous issue date: 1998

Our objective was to determine the effects of feeding 25-hydroxyvitamin D3 [25(OH)D3], or vitamin D3 (cholecalciferol) on plasma, mineral, and metabolite concentrations, mineral balance, mineral excretion, rumination, energy balance, and milk production of dairy cows. We hypothesized that supplementing 3 mg/d of 25(OH)D3 during the prepartum period would be more effective than supplementing vitamin D3 at the National Research Council (2001) levels to minimize calcium imbalance during the transition period and improve milk production of dairy cows. Forty multiparous, pregnant nonlactating-Holstein cows were enrolled in this study. Body weight, body condition score, parity, and milk yield in the previous lactation (mean ± standard deviation) were 661 ± 59.2, 3.46 ± 0.35, 1.79 ± 0.87, and 33.2 ± 6.43 kg/d, respectively. Cows were enrolled into the blocks (n = 20 for each treatment) at 30 d of the expected day of calving to receive an acidogenic diet (373 g/kg of neutral detergent fiber and 136 g/kg of crude protein, dry matter basis; -110 mEq/kg) associated with the treatments: (1) control (CTRL), vitamin D3 at 0.625 mg/d (equivalent to 25,000 IU of vitamin D3/d) or (2) 25(OH)D3 at 3 mg/d (equivalent to 120,000 IU of vitamin D3/d). All cows were fed with the base ration for 49 d after calving. Blood samples were taken on d 7, 0, 1, 2, 21, and 42, relative to calving. No effect of treatment was observed for prepartum dry matter intake or body condition score. A trend for increase of ionized Ca was observed for the cows fed 25(OH)D3, compared with the CTRL, but no effect of treatment was detected for total Ca or total P. Feeding 25(OH)D3 increased colostrum yield. The plasmatic concentration of 25-hydroxyvitamin D3 was increased with 25(OH)D3 supplementation. 25-Hydroxyvitamin D3 supplementation increased plasma glucose concentration at parturition. The postpartum dry matter intake was not influenced by treatments. Feeding 25(OH) D3 increases milk yield, 3.5% fat-corrected milk, and energy-corrected milk and improves milk yield components in early lactation. Overall, these findings suggest that 25(OH)D3 at 3 mg/d can improve the energy metabolism and lactation performance, compared with the current-feeding practice of supplementing vitamin D3 at 0.625 mg/d. Made available in DSpace on 2022-07-07T12:20:19Z (GMT). No. of bitstreams: 1 Effects-of-feeding-25-hydroxyvitamin-D3-with-an-acidogenic-diet.pdf: 810895 bytes, checksum: 6b70fe5ba2a4620281c061a6a0d712a1 (MD5) Previous issue date: 2022

This study evaluated if the milk ring test (MRT) used to the brucellosis diagnostic at dairy herd level can be done in milk samples with conservative (Bronopol®) collected to the somatic cell count (SCC) that is used to mastitis monitoring. It were analyzed 38 bulk tank milk samples (BTMS) from 19 dairy herds artisanal cheese producers and 36 BTMS from a brucellosis free dairy herd, used as negative control (NC) and positive control (PC), when was added serum from vaccinated animals. The milk samples were collected in two different bottles (with or without Bronopol®). All the 38 BTMS from artisanal cheese producers (samples with and without Bronopol®) were non-reagent to MRT, as all NC. All PC were reagent to MRT, without interference of Bronopol®. Results showed that the milk sample used to SCC presented the proportion of agreement of results in all milk samples (100%), that is, false positive and false negative results were not observed. Results indicated that Bronopol® did not interfere with the color in the time of MRT reading suggesting that the same milk samples could be used to monitoring mastitis and brucellosis. RESUMO: O objetivo deste estudo foi avaliar se o teste do anel do leite (TAL), utilizado para o diagnóstico da brucelose em nível de rebanho leiteiro, pode ser realizado em amostras de leite com conservador (Bronopol®) coletado para contagem de células somáticas (CCS) que é utilizado para monitoramento de mastite. Foram analisadas 38 amostras de leite de tanques de expansão (ALTE) de 19 rebanhos leiteiros produtores de queijo artesanal e 36 ALTE de rebanho leiteiro livre de brucelose, utilizadas como controle negativo (CN) e controle positivo (CP), quando foi adicionado soro de animais vacinados. As amostras de leite foram coletadas em dois frascos diferentes (com e sem Bronopol®). Todos as 38 ALTE de produtores artesanais de queijo (amostras com e sem Bronopol®) foram não reagentes ao TAL, como todos os CN. Todos os CP foram reagentes ao TAL, sem interferência do Bronopol®. Os resultados mostraram que a amostra de leite utilizada para CCS apresentaram a proporção de concordância dos resultados em todas as amostras de leite (100%), ou seja, não foram observados resultados falso-positivos e falso-negativos. Os resultados indicam que o Bronopol® não interferiu na cor no momento da leitura do TAL, sugerindo que as mesmas amostras de leite poderiam ser usadas para monitorar mastite e brucelose Made available in DSpace on 2022-06-14T13:26:13Z (GMT). No. of bitstreams: 1 Ring-test-in-milk-samples-preserved-with-Bronopol.pdf: 434937 bytes, checksum: 4a207aa1a41d27da10a579a8e328a8ac (MD5) Previous issue date: 2023

Elephant grass is a promising plant for economic and sustainable energy production. However, adapted cultivars and efficient strategies for selecting genotypes aimed at energy biomass production is essential. Remote sensing techniques provide spatiotemporal information from plants in an agile, non-destructive and non-invasive way. The present study aimed to use remote sensors onboard an unmanned aerial vehicle (UAV) to monitor elephant grass genotypes and assist in plant phenotyping for energy biomass production. The experimental plots were imaged in the visible and near infrared bands. Imaging was carried out in 66 experimental plots in the José Henrique Bruschi Experimental Field (CEJHB), located in Coronel Pacheco, MG, Brazil. The experiment was arranged in a randomized block design with three replications, and 22 elephant grass genotypes were evaluated. The aggregated index iMAPNDRE was strongly correlated with the dry matter production observed in the field, therefore a method with potential application for estimating the biomass of elephant grass genotypes. Thus, sensors aboard UAV platforms can assist breeders to select the best elephant grass genotypes for energy production. Made available in DSpace on 2022-01-23T01:56:40Z (GMT). No. of bitstreams: 1 Unmanned-aircraft.pdf: 584154 bytes, checksum: 475c4cdcc49b856ec5b3ecfe765dd2f3 (MD5) Previous issue date: 2022

Elephantgrass (Pennisetum purpureum Schum. syn. Cenchrus purpureus) is one of the most important forage plants worldwide, cultivated in almost all tropical and subtropical regions due to its high potential for dry matter production, nutritional value, acceptability by different animal species and categories, vigor, and persistence. It has shown great potential for biomass energy production and other forms of non-forage use. This study aimed to review the current knowledge about the cultivation and use elephantgrass focused on pasture and silage. The study also describes the main morphological, genetic, and cytogenetic characteristics of the species, and methods and strategies for obtaining improved cultivars. The release of dwarf type cultivars for grazing and cultivars with high-yield potential for silage has increased the interest in the cultivation of elephantgrass in the beef and dairy cattle production. RESUMO - O capim-elefante (Pennisetum purpureum Schum. sin. Cenchrus purpureus) é uma das mais importantes plantas forrageiras, sendo cultivado em quase todas as regiões tropicais e subtropicais do globo devido ao seu elevado potencial de produção de forragem, valor nutritivo, aceitabilidade por diferentes categorias e espécies de animais, vigor e persistência. O capim elefante também enorme potencial para produção de biomassa energética e outras formas de uso não forrageiro. O objetivo deste trabalho foi revisar o conhecimento atual sobre o cultivo e uso do capim elefante, principalmente como pastagem e na forma de silagem. O estudo também descreve as principais características morfológicas, genéticas e citogenéticas, bem como os métodos e estratégias para obtenção de cultivares melhoradas. O desenvolvimento de cultivares melhoradas de porte baixo, específicas para pastejo, e de elevado potencial produtivo, para ensilagem, tem resultado no aumento de interesse pelo cultivo dessa forrageira na produção de carne e leite. Made available in DSpace on 2021-08-31T19:00:24Z (GMT). No. of bitstreams: 1 Elephantgrass-tropical.pdf: 5654375 bytes, checksum: 844385cc68a18af9c589f96e90a3f5b7 (MD5) Previous issue date: 2021

This study evaluated the effect of energy supplementation with ground corn on the performance of crossbred dairy cows in BRS Kurumi elephant grass pastures managed under rotational stocking during the rainy season. Six Holstein × Gyr cows were used, with average milk production, body weight, body condition score, and days in milk of 18.0±2.89 kg day−1, 560±66 kg, 2.50±0.21, and 99±12, respectively. The experimental design used was the complete reversion (switchback), and the evaluations were conducted over three grazing cycles, with adaptation periods of 14 days and six days of sample collection. The concentrate supplement (ground corn) was supplied twice a day, at a rate of 2 kg cow−1 day−1 in the morning and 1 kg cow−1 day−1 in the afternoon (as-fed basis). A reduction of 23.4% was observed in the pasture dry matter (DM) intake (PDMI) in cows that received energy supplementation, which corresponds to 2.96 kg day-1 less of PDMI when compared to the group without supplementation. This corresponds to a substitution rate of 1.1 kg of pasture per kg of concentrate consumed (DM basis), which reduced the intake (kg cow−1 day−1) of neutral detergent fiber and crude protein by 18.9% and 13.9% in the cows that received ground corn. There were increases of 11.8%, 9.0%, and 10.1%, respectively, in the milk yield, the 3.5% fat-corrected milk yield, and the energy-corrected milk yield of the cows that received ground corn. The response to supplementation in kg of milk per kg of DM of concentrate consumed was 0.57, and the milk contents of fat, protein, and lactose did not differ between treatments. The energy supplementation with 3 kg cow−1 day−1 of ground corn resulted in an increase of 11.8% in the milk yield of Holstein × Gyr dairy cows grazed on BRS Kurumi elephant grass, as well as promoted increases in the daily protein, lactose, and total solids yields. In addition, the provision of 3 kg day−1 of ground corn for lactating cows grazing on BRS Kurumi increased the efficiency in the use of dietary nitrogen. Made available in DSpace on 2021-08-16T13:00:39Z (GMT). No. of bitstreams: 1 Performance-crossbred.pdf: 181350 bytes, checksum: 13760d624af8d618e5c2eb8b05254d98 (MD5) Previous issue date: 2021

RESUMO As raças taurinas de origem ibérica Limonero e Carora (Bos primigenius taurus) possuem o fenótipo de pelo curto, liso e com baixa densidade folicular, o que confere a esses animais maior tolerância térmica e melhor produtividade em regiões quentes. Diferentes mutações associadas a esse fenótipo foram descritas no gene do receptor de prolactina PRLR, localizado no cromossomo bovino BTA20. Uma mutação recentemente encontrada é a substituição do nucleotídeo C por T, SNP 39136666 (p. R497*), no exon 11, que gera um códon de parada e, consequentemente, uma menor isoforma desse receptor. Neste trabalho, desenvolveu-se um protocolo rápido e de baixo custo para detecção desse SNP, utilizando-se a técnica de tetra-primer ARMS-PCR. Assim, foi possível detectar essa mutação nas raças brasileiras de origem ibérica localmente adaptadas: Caracu, Crioulo Lageano, Mocho Nacional e Pantaneiro. O alelo T foi mais frequente na raça Caracu (80%), enquanto o alelo C foi mais frequente na raça Crioulo Lageano (84%). Essa simples metodologia pode ser usada para genotipar esse SNP e ajudar na aplicação dessas informações moleculares em programas de melhoramento focados na tolerância térmica em bovinos taurinos e seus mestiços.

Traditional procedures for biomass estimation usually use destructive methods with great demands on time, resources, and labor. The development of models for automated estimation of pasture biomass, particularly from images captured by Unmanned Aerial Vehicle (UAV), in addition to high spatiotemporal resolution combined with flexibility in image acquisition, provides agility, the economy of resources, and labor. The objective of this work was to establish a technical feasibility study for the use of multispectral sensors onboard an Unmanned Aerial Vehicle (UAV) to estimate the vigor classes of Brachiaria ruziziensis pastures. For this purpose, imaging cameras in the visible (RGB), near-infrared and red edge ranges were used for continuous monitoring of 20 pasture paddocks with an area of 1,350 m2 each, totaling 27,000 m2 of the experimental area. The indices performed well and were sensitive in class discrimination at intervals that range from soil exposure and stresses caused by pest and disease infestation (low vigor) to conditions in which the vegetation is in good development, in class intervals with high levels of vegetation and, consequently, pointing to high values of biomass. Made available in DSpace on 2021-12-29T02:02:03Z (GMT). No. of bitstreams: 1 Estimate-vigor.pdf: 616163 bytes, checksum: 238dd95d008ca34f7e3df28c14b2b693 (MD5) Previous issue date: 2021

BACKGROUND: Ionophore antibiotics improve the efficiency of energy metabolism, which has driven their use as a feed additive in ruminants for decades. Currently, they have not been approved in many countries, generating a challenge for the immediate search for plant extracts with a similar mode of action on rumen metabolism. This study evaluated the effects of enriched Prosopis juliflora (mesquite) piperidine alkaloid extract (MPA) levels as an alternative phytoadditive to sodium monensin (MON) in sheep. RESULTS: The MPA diet did not differ from MON with regard to nutrient intake. A quadratic effect (P < 0.05) was observed for organic matter and neutral detergent fibre digestibility, with respective maximum point at 25.40 and minimum point at 0.95 mg kg-1 MPA. The MPA levels linearly decreased (P < 0.05) faecal nitrogen loss. MPA did not differ from MON with regard to nutrient digestibility, and MPA levels increased (P < 0.05) the proportion of digestible energy and metabolizability from dietary gross energy. The MPA levels linearly decreased (P < 0.05) enteric CH4 production, the yield showing lower (P < 0.05) energy loss as CH4 than MON. CONCLUSION: The results show that MPA levels of 17.3 and 27.8 mg kg-1 are enteric CH4 inhibitors and enhance energy and protein utilization, indicating a promising alternative to MON for ruminants. Made available in DSpace on 2022-08-15T04:00:42Z (GMT). No. of bitstreams: 1 Prosopis-juliflora-piperidine-alkaloid-extract-levels-in-diet-for-sheep-change-energy.pdf: 444293 bytes, checksum: e23ba7fb96dc508852a5618ca9eb6494 (MD5) Previous issue date: 2022

RESUMEN - Diversos estudios han comprobado que la progesterona tiene un efecto directo en la calidad ovocitaria y el desarrollo inicial embrionario. El objetivo de este estudio fue evaluar el efecto de la concentración de la progesterona (P4) plasmática en el desarrollo de embriones in vitro en vacas de raza Bos taurus taurus (Holstein) y Bos taurus indicus (Gyr). Se utilizaron vacas Holstein y Gyr multíparas, presincronizadas con la aplicación de dos dosis de D-cloprostenol con intervalo de once días. Posteriormente, se distribuyeron en uno de tres grupos experimentales inducidos a diferentes niveles plasmáticos de progesterona. El grupo control fue sincronizado utilizando únicamente D-cloprostenol sin progesterona exógena, el grupo progesterona baja recibió un implante auricular de norgestomet de segundo uso y al grupo progesterona alta se le aplicaron dos implantes auriculares de norgestomet nuevos. Los resultados evidencian que la concentración plasmática de progesterona fue significativamente diferente (P < 0,05) tanto para las vacas Holstein (0,22 ± 0,15, 2,23 ± 0,17 y 5,32 ± 0,22 ng/mL) como para las vacas Gyr (0,24 ± 0,19, 2,05 ± 0,17, 4,85 ± 0,20 ng/mL) entre los grupos control, progesterona baja y progesterona alta, respectivamente. Las vacas Gyr presentaron diferencia (P < 0,05) en la tasa de clivaje del grupo progesterona baja en relación con los grupos control y progesterona alta (87,9 % ± 0,11 vs 77,5 % ± 0,13 y 76,4 % ± 0,10, respectivamente) y en la variable tasa de blastocistos del grupo progesterona baja (48,3 % ± 0,16) en relación con el grupo control (35,8 % ± 0,10) y el grupo progesterona alta (30,4 % ± 0,20). Se concluye que la progesterona tuvo efecto sobre el desarrollo embrionario en vagas de raza Gyr, el cual no se evidenció en las vacas de raza Holstein. ABSTRACT - Studies have shown that progesterone has a direct effect on oocyte quality and early embryonic development. The objective of this study was to evaluate the effect of plasma progesterone (P4) concentration on in vitro embryo development in Bos taurus taurus (Holstein) and Bos taurus indicus (Gyr) cows. Multiparous Holstein and Gyr cows were used, and they were presynchronized with the application of two doses of D-cloprostenol with an interval of 11 days. They were latter distributed in one of three experimental groups induced to different plasma levels of progesterone: control group was synchronized using only D-cloprostenol without exogenous progesterone, low progesterone group received an auricular implant of norgestomet of second use, and high progesterone group received two new auricular implants of norgestomet. The plasma progesterone concentration was significantly different (P < 0.05) for both Holstein cows (0.22 ± 0.15, 2.23 ± 0.17 and 5.32 ± 0.22 ng/mL) and Gyr cows (0.24 ± 0.19, 2.05 ± 0.17, 4.85 ± 0.20 ng/mL) between control, low progesterone, and high progesterone groups respectively. Gyr cows presented differences (P < 0.05) in the cleavage rate of the low progesterone group in relation to the control and high progesterone groups (87.9 % ± 0.11 vs. 77.5 % ± 0.13 and 76.4 % ± 0.10, respectively) and in the variable blastocyst rate of the low progesterone group (48.3 % ± 0.16) in relation to the control group (35.8 % ± 0.10) and the high progesterone group (30.4 % ± 0.20). It is concluded that there is an effect of progesterone on embryonic development of Gyr cows. However, this effect is not evidenced in Holstein cows. Made available in DSpace on 2022-06-09T11:19:50Z (GMT). No. of bitstreams: 1 Efecto-de-la-progesterona-plasmatica-en-la-competencia-para-el-desarrollo-embrionario.pdf: 255349 bytes, checksum: 1805cc445c7c4eae516f25506817085c (MD5) Previous issue date: 2022

The livestock performance in tropical regions has been limited by environmental conditions that causes heat stress and favors the development of parasites and diseases, impairing animal health. Heat stress disturbs animal homeostasis and afects animal production and fertility, with negative impacts on meat and milk quality. Flies and ticks proliferate easily under hot-humid weather, which makes difcult the control of their population, resulting in an increased parasitism. Tropical pastures usually have high dry matter production, but it is challenging to keep high production and quality under diferent environmental conditions throughout the year, constraining animal performance. Several strategies have been adopted in an attempt to overcome such hurdles in the tropical regions, but defnitive solutions are yet to be implemented. In the last 20 years, biotechnologies, such as in vitro embryo production and genomic selection, have played an important role on cattle production in tropical countries. Genome editing (GnEd) is the novel tool in the toolbox for cattle production. GnEd with genomic selection ofers the opportunity to boost the genetic gain in breeding programs of tropical cattle in fewer generations. It can be applied for disease resistance, to control parasite population, and to improve pasture quality and tolerance to biotic and abiotic stresses, favoring animal health and nutrition. Moreover, there is a perspective for the use of GnEd to control cattle methane emission by editing genes of methanogens present in the rumen. Although GnEd can already be applied to improve some traits, studies are still required for the identifcation of candidate genes in animals, tropical pastures, parasites, and microorganisms that can be targeted by gene editing in order to ofer a robust contribution to the improvement of cattle production in the hot regions. Some examples of the use of GnEd are presented in this review, focusing on new perspectives of using GnEd to increase cattle production under the challenges of the tropical environments. Made available in DSpace on 2022-03-22T13:00:21Z (GMT). No. of bitstreams: 1 Genome-editing.pdf: 3034362 bytes, checksum: 710e9d57d3d55119b9a76cef0de78148 (MD5) Previous issue date: 2022

No artigo: Roberta Aparecida Carnevalli.

Waste is a environmental problem. Waste generation increases exponentially, and the management to minimize environmental impacts. The launch of the 17 (SDGs), by the U.N., aimed to mobilize to implement public policies based on the pillars of sustainability. At (studied company) routines of research laboratorial activities, farms and administrative areas generate waste. We evaluated the waste management at the (studied company) research institution. We applied methodologies for a comprehensive view. Gravimetric method for characterization of waste in each category. Monitoring of waste generator points resulted in the diagnosis of waste separation. The methodology of the Discourse of the Collective Subject was used to understand the perception of employees. We development the SWOT matrix, to identify the factors that affect the waste management. We understand and rank the strengths, weaknesses, opportunities and threats, and they can be used for the development of management. RESUMO - O lixo é um problema ambiental. A geração de resíduos aumenta exponencialmente, e a gestão minimiza os impactos ambientais. O lançamento dos 17 (ODS), pela ONU, teve como objetivo mobilizar para a implementação de políticas públicas baseadas nos pilares da sustentabilidade. Nas rotinas de atividades laboratoriais de pesquisa, fazendas e áreas administrativas geram resíduos (empresa estudada). Avaliou-se a gestão de resíduos em uma instituição de pesquisa. Aplicou-se metodologias para uma visão abrangente. Método gravimétrico para caracterização de resíduos em cada categoria. O monitoramento dos pontos geradores de resíduos resultou no diagnóstico da separação de resíduos. A metodologia do Discurso do Sujeito Coletivo (DSC) foi utilizada para compreender a percepção dos funcionários. Desenvolveu-se uma matriz SWOT, para identificar os fatores que afetam a gestão de resíduos. Foram entendidos e classificados os pontos fortes, fracos, oportunidades e ameaças, e eles podem ser usados para o desenvolvimento da gestão. Made available in DSpace on 2022-07-18T14:19:37Z (GMT). No. of bitstreams: 1 Solid-waste-management-performance-a-case-study-in-a-research-institution.pdf: 350214 bytes, checksum: d11807291cd87f0ec902937a04b4a7e5 (MD5) Previous issue date: 2022

RESUMO - Os dejetos animais podem ser utilizados em biodigestores anaeróbicos com intuito de produzir biogás e biofertilizante. Entretanto, a identificação e o conhecimento do perfil de resistência a antimicrobianos da microbiota presente no composto se faz necessário. Microrganismos presentes nas amostras foram identificados genotipicamente pelo sequenciamento do rRNA 16S. O perfil de susceptibilidade a antimicrobianos foi determinado pelo método de disco-difusão. Os grupos microbianos encontrados foram os Bacilos Gram Negativos da família Enterobacteriaceae e cocos Gram positivos. Quanto a susceptibilidade aos antimicrobianos, para os isolados do gênero Staphylococcus a penicilina foi a droga que apresentou o maior índice de resistência (78,9%), seguida da oxacilina (57,9%), sendo a maioria dos isolados (94,7%) sensíveis à combinação de ampicilina-sulbactam e ao levofloxacino (78,9%). Para os isolados do gênero Enterococcus os maiores índices de resistência foram detectados para a rifamicina (48%) e eritromicina (32%), com elevada sensibilidade ao levofloxacino (88%) e à vancomicina (80%). As linhagens de Escherichia coli avaliadas apresentaram uma alta sensibilidade à amicacina (85,7%) e a maior resistência se deu para o antimicrobiano ampicilina (42,8%). A utilização do biofertilizante gerado deve ser criteriosa devido à persistência de espécies potencialmente patogênicas no efluente final, onde algumas das quais apresentam relevante resistência a antimicrobianos. ABSTRACT - Animal waste can be used in anaerobic digesters to produce biogas and biofertilizers. However, the identification and knowledge of the antimicrobial resistance profile of the microbiota present in the compound is necessary. Microorganisms present in the samples were genotypically identified by 16S rRNA sequencing. The antimicrobial susceptibility profile was determined by the disk-diffusion method. The microbial groups found were Gram-negative Bacillus of the Enterobacteriaceae family and Gram-positive cocci. As for antimicrobial susceptibility, for the isolates of the Staphylococcus genus, penicillin was the drug that presented the highest resistance rate (78.9%), followed by oxacillin (57.9%), with most isolates (94.7 %) sensitive to the combination of ampicillin-sulbactam and levofloxacin (78.9%). For isolates of the Enterococcus genus, the highest resistance rates were for rifamycin (48%) and erythromycin (32%), with high sensitivity to levofloxacin (88%) and vancomycin (80%). The Escherichia coli strains evaluated showed high sensitivity to amikacin (85.7%) and the highest resistance was to the antimicrobial ampicillin (42.8%). The use of the generated biofertilizer must be judicious due to the persistence of potentially pathogenic species in the final effluent, where some of which present relevant resistance to antimicrobials. Made available in DSpace on 2022-07-22T10:20:13Z (GMT). No. of bitstreams: 1 Identificacao-e-perfil-de-sensibilidade-a-antimicrobianos-de-bacterias.pdf: 388959 bytes, checksum: c0125244f7059f2737e83a9a12fd1fda (MD5) Previous issue date: 2022

Rhipicephalus microplus causes huge losses in cattle. Host genetic background greatly affects the immune efficiency in resistance or susceptibility to tick infestation, which is one of the many factors that play a role on that trait. We performed a systematic review of genome-wide association studies (GWAS) for tick resistance in cattle resulting in 1353 candidate genes for post-GWAS analyses. From those, genes showing possible structural variants from the bovine genome were classified by the Variant Effect Predictor from Ensembl. Ninety-two candidate genes showed potential structural variants in 5' UTR and coding region and were used for functional annotation. Enriched biological processes (e.g. regulation of eosinophil chemotaxis, RIG-I signalling pathway and monocyte differentiation) and candidate genes (e.g. DAPK2, PUM1, ACIN1, INPP5D) linked with immune system function were identified and thus associated with tick resistance. Besides, gene-transcription factors (TFs) networks were obtained from TFs associated with immune system (FOXO3, PPARG, STAT3, NFKB1, GATA3 and ARNT) and the candidate genes associated with tick resistance in cattle highlighted (e.g. OR4L1, PNP, LRRIQ1, GIMAP8, MYO6, MEP1A and LRFN2). Thus, promising candidate genes with a possible functional role for tick resistance in cattle are presented for further in vitro and/or in vivo analyses. Made available in DSpace on 2022-07-25T13:20:05Z (GMT). No. of bitstreams: 1 Candidate-genes-for-tick-resistance-in-cattle.pdf: 1963506 bytes, checksum: b97dc4a9f2a268ebd1d7f0d2f8ecec48 (MD5) Previous issue date: 2022

We aimed to measure the efficiency of visual selection of plant vigor for green biomass production of U. ruziziensis using single- and multitrait approaches to maximize the predictive accuracy of the genetic value. The green biomass production and plant vigor of 254 U. ruziziensis clones were measured over nine evaluation cuttings to determine the efficiency of these approaches for production improvement. Individual and multicutting analyses were performed under single-trait and multitrait approaches using mixed models. The efficiency of visual selection was assessed by measuring plant vigor based on direct and indirect genetic gains. Plant vigor showed a high genetic association with green biomass and could be selected for production, especially in the initial phases of breeding programs. The multitrait approach was superior to the single-trait approach in predicting the genetic value of the clones, and it can be used in U. ruziziensis breeding programs. Made available in DSpace on 2022-08-25T18:19:22Z (GMT). No. of bitstreams: 1 Efficiency-of-indirect-selection-for-green-biomass.pdf: 397687 bytes, checksum: ec35d48775bd35e36079a87ccdddb536 (MD5) Previous issue date: 2022

This study evaluated the effect of crude protein (CP) reduction in four diets (156, 139, 132, and 127 g Kg-1 DM) maintaining constant metabolizable protein (188 g/day) on the follicular fluid and cumulus-oocyte complexes of mid-lactating Girolando cows. Twenty-two Girolando cows with average of 21.55 ±3.19 L daily milk yield, 105.30 ±22.62 days in lactation and 3.22 ±0.03 body condition score were selected. To reduce CP in diets and maintain constant metabolizable protein, urea and soybean meal were gradually replaced by lignosulfonate-treated soybean meal (SoyPass®, Cargill), resulting in an increase in rumenundegradable protein and a reduction in rumen degradable protein. A linear and quadratic reduction was observed in the plasma and follicular fluid urea nitrogen concentration following CP reduction, with the most intense reduction occurring in the 127 g Kg-1 DM group (p

The objective of this study was to estimate sugar content variation (°Brix) in 95 accessions from the elephant grass germplasm active bank of Embrapa Dairy Cattle research center, located in Coronel Pacheco, MG, Brazil. The accessions with the highest sugar content were identified, and the effect of plant age on sugar concentration was evaluated. The experiment was conducted in randomized blocks design with two replications. Sugar content analysis occurred twice during the growth-cycle (at 70 and 100 days) along two points of the stem, one 30 cm from the base and the other at the midpoint. The analysis of variance considered the split plot model, with accessions as main plots and plant age as subplots. The means were compared using the Scott Knott test. While there was sugar content variation between accessions, increased plant age had no significant effect on the sugar content. However, some accessions did have a significant increase or decrease in sugar content as they aged. The highest and lowest mean sugar content was 6.96% (in the accession BAG80) and 4.03% (in the accession BAG13) °Brix, respectively Made available in DSpace on 2021-08-22T01:54:43Z (GMT). No. of bitstreams: 1 Sugar-content.pdf: 475552 bytes, checksum: c5a3708917b5d64b25098f12ce41d690 (MD5) Previous issue date: 2022

O que a transição marcante do perfi l demográfico da população sinaliza sobre a complexa previsão de consumo de lácteos no Brasil?

RESUMO - Os padrões alimentares podem variar nas regiões geográficas brasileiras, que foram afetadas de forma diferente pela pandemia de COVID-19. Este estudo teve como objetivo verificar se o local de residência dos indivíduos afetou o consumo de laticínios durante a pandemia, considerando tanto a quantidade de produto consumida quanto os fatores que influenciam a decisão de compra. Resíduos de Pearson ajustados foram utilizados para avaliar a associação entre a variável estado e aquelas relacionadas ao consumo de laticínios. A coleta de dados foi realizada por meio de aplicação de questionário online, no período de 23 de abril a 3 de maio de 2020. Os resultados mostraram que, para a maioria dos laticínios, foi observada associação significativa entre o local de residência e o consumo de laticínios. Uma maior associação com a manutenção ou maior consumo foi observada para as regiões com maior consumo de laticínios, sendo a marca que os consumidores estavam acostumados a comprar foi o fator determinante no momento da compra, mesmo diante de uma crise financeira. Também foi possível determinar os estados que estavam mais atentos às ações das empresas durante a pandemia e a importância da boa alimentação em uma crise de saúde pública. Por fim, os resultados podem contribuir para um melhor entendimento das particularidades do consumo de laticínios no Brasil, além de avaliar o comportamento do consumidor na atual crise econômica. ABSTRACT - Dietary patterns can vary in the Brazilian geographic regions, which have been affected differently by the COVID-19 pandemic. This study aimed to determine whether the place of residence of the individuals affected the consumption of dairy products during the pandemic, considering both the amount of product consumed and the factors that influence the purchase decision. Adjusted Pearson residuals were used to evaluate the association between the variable state and those related to the consumption of dairy products. Data collection was performed using an online questionnaire application, from April 23 to May 3, 2020. The results showed that, for most dairyproducts, a significant association was observed between the place of residence and the consumption of dairy products. A greater association with the maintenance or higher consumption was observed for the regions with a higher intake of dairy products, and the brand that consumers were used to buy was the determining factor at the time of purchase, even in the face of a financial crisis. It was also possible to determine the states that were most aware of the actions of companies during the pandemic and the importance of good nutrition in a public health crisis. Finally, the results can contribute to a better understanding of the particularities of the consumption of dairy products in Brazil, besides assessing the consumers? behavior in the current economiccrisis. Made available in DSpace on 2022-08-15T18:19:39Z (GMT). No. of bitstreams: 1 A-localizacao-geografica-como-fator-determinante-na-compra-de-laticinios-durante-a-pandemia.pdf: 961491 bytes, checksum: 8f37065cbf0b316e2e08c55902628c8e (MD5) Previous issue date: 2022

Objective: The aim of this study was to estimate genetic parameters for 305-day cumulative milk yield and components, growth, and reproductive traits in Guzerá cattle. Methods: The evaluated traits were 305-day first-lactation cumulative yields (kg) of milk (MY305), fat (FY305), protein (PY305), lactose (LY305), and total solids (SY305); age at first calving (AFC) in days; adjusted scrotal perimeter (cm) at the ages of 365 (SP365) and 450 (SP450) days; and adjusted body weight (kg) at the ages of 210 (W210), 365 (W365) and 450 (W450) days. The (co)variance components were estimated using the restricted maximum likelihood method for single-trait, bi-trait and tri-trait analyses. Contemporary groups and additive genetic effects were included in the general mixed model. Maternal genetic and permanent environmental effects were also included for W210. Results: The direct heritability estimates ranged from 0.16 (W210) to 0.32 (MY305). The maternal heritability estimate for W210 was 0.03. Genetic correlation estimates among milk production traits and growth traits ranged from 0.92 to 0.99 and from 0.92 to 0.99, respectively. For milk production and growth traits, the genetic correlations ranged from 0.33 to 0.56. The genetic correlations among AFC and all other traits were negative ( 0.43 to 0.27). Scrotal perimeter traits and body weights showed genetic correlations ranging from 0.41 to 0.46, and scrotal perimeter and milk production traits showed genetic correlations ranging from 0.11 to 0.30. The phenotypic correlations were similar in direction (same sign) and lower than the corresponding genetic correlations. Conclusion: These results suggest the viability and potential of joint selection for dairy and beef traits in Guzerá cattle, taking into account reproductive traits. Made available in DSpace on 2022-07-12T10:19:22Z (GMT). No. of bitstreams: 1 Genetic-study-of-quantitative-traits-supports-the-use-of-Guzera.pdf: 565236 bytes, checksum: dfaa8a1ebf81c017549a592d9e4ae054 (MD5) Previous issue date: 2022

Research on genes affecting phenotypic variation in milk production and composition from indicine (Bos indicus) cattle is imperative, since these breeds are important tropical genetic resources, and there have been few studies investigating the genetic basis of these traits. We identified polymorphisms in k-casein (CSN3), b-lactoglobulin (LGB), thyroglobulin (TG) and prolactin (PRL) and examined their effect on milk and composition traits in the Guzerá breed. DNA samples of 260 Guzerá cattle selected for dual purpose use were genotyped. Allele frequencies observed for the A allele were 0.83, 0.18 and 0.25 respectively for CSN3, LGB and PRL genes, while for the TG gene T allele had an allele frequency of 0.09. For all polymorphisms evaluated, observed genotypic frequencies were in agreement with those expected according to the Hardy-Weinberg Equilibrium hypothesis. A polymorphism association study evaluated breeding values (BV) for 305-day milk (BV-M), fat (BV-F), and protein (BV-P) production, employing the allele substitution model using a sample of 139 cows belonged to 27 full and half-sib families of a MOET (multiple ovulation and embryo transfer) selection nucleus. Association was found between the LGB polymorphism and BV-M, BV-F and BV-P. Animals with LGB AA genotype have, on average, higher BV when compared to animals with LGB AB and BB genotypes (277.85 kg for BV-M, 12.09 kg for BV-F and 9.33 kg for BV-P). These findings contribute to a better understanding on the influence of these polymorphisms on milk production traits in Guzerá cattle. Made available in DSpace on 2022-08-25T17:20:01Z (GMT). No. of bitstreams: 1 Polymorphisms-in-genes-coding-milk-proteins-and-protein-hormones.pdf: 773850 bytes, checksum: 7276f37bf01b3e47be7ff66f1064736f (MD5) Previous issue date: 2022

Made available in DSpace on 2022-04-29T19:43:04Z (GMT). No. of bitstreams: 1 Oscilacoes-e-correlacoes.pdf: 628100 bytes, checksum: fa7e4b8286d22b889d84fd62d3059f92 (MD5) Previous issue date: 2022

Background: Elephant grass plants propagated by seeds are more likely to have injuries to herbicides, in their initial cultivation phase, when compared to those from cuttings. There are selective herbicides for elephant grass developed from seeds. Objective: This work evaluated the tolerance of elephant grass implanted by seeds to auxinic herbicides and tembotrione. Methods: Two experiments were conducted in the municipalities of Valença, Rio de Janeiro State, Brazil, and Coronel Pacheco, Minas Gerais State, Brazil. The experimental design was in randomized complete blocks, with four replications. The experimental treatments were: Auxinic herbicides {fluroxypyr + picloram [160 + 160 g a.e. ha-1]; fluroxypyr + aminopyralid [160 + 80 g a.e. ha-1]; fluroxypyr + triclopyr [160 + 480 g a.e. ha-1]; 2,4-D amine (1,340 g a.e. ha-1); 2,4-D amine + picloram [720 + 45 g a.e. ha-1]}, and tembotrione (84 g a.i. ha-1 without mineral oil), in addition to the control without herbicides. Results: Tembotrione was the most phytotoxic treatment to elephant grass propagated by seed, causing leaf bleaching and, consequently, reducing forage dry matter yield. The treatments with fluroxypyr + picloram, fluroxypyr + aminopyralid, fluroxypyr + triclopyr, 2,4-D and 2,4-D + picloram did not cause symptoms of phytotoxicity capable of providing a reduction in forage productivity, being potential herbicides for spraying in seed-propagated elephant grass fields. Conclusions: the herbicides: fluroxypyr + picloram, fluroxypyr + aminopyralid, fluroxypyr + triclopyr, 2,4-D and 2,4-D + picloram can be sprayed in the elephant grass developed from seeds. RESUMO - Introdução: Plantas de capim-elefante propagadas por sementes têm maior possibilidade em apresentar injúrias a herbicidas, na sua fase inicial de cultivo, quando comparadas àquelas provenientes de estacas. Há herbicidas seletivos para o capim-elefante proveniente de sementes. Objetivo: Este trabalho avaliou a tolerância do capim-elefante implantado por sementes a herbicidas auxínicos e ao tembotrione. Métodos: Dois experimentos foram conduzidos nos municípios de Valença, RJ, e em Coronel Pacheco, MG. O delineamento experimental foi em blocos casualizados, com quatro repetições. Os tratamentos foram: herbicidas auxínicos {fluroxypyr + picloram [160 + 160 g e.a. ha-1]; fluroxypyr + aminopyralid [160 + 80 g e.a. ha-1]; fluroxypyr + triclopyr [160 + 480 g e.a. ha-1); 2,4-D (1.340 g e.a. ha-1); 2,4-D + picloram [720 + 45 g e.a. ha-1]} e o tembotrione (84 g i.a. ha-1 sem adição de óleo mineral), além da testemunha se aplicação. Resultados: O tembotrione foi o tratamento mais fitotóxico ao capimelefante propagado por sementes, causando branqueamento de folhas e, consequentemente, redução na produtividade de matéria seca de forragem. Os tratamentos com fluroxypyr + picloram, fluroxypyr + aminopyralid, fluroxypyr + triclopyr, 2,4-D e 2,4-D + picloram não causaram sintomas de fitotoxicidade capazes de proporcionar redução na produtividade de forragem, sendo herbicidas potenciais para aplicação em capim-elefante propagado por sementes. Conclusões: os herbicidas fluroxypyr + picloram, fluroxypyr + aminopyralid, fluroxypyr + triclopyr, 2,4-D e 2,4-D + picloram podem ser aplicados em capim-elefante propagado por sementes. Made available in DSpace on 2022-08-05T13:20:17Z (GMT). No. of bitstreams: 1 Auxinic-herbicides-and-tembotrione-sprayed-on-seed-propagated-elephant-grass.pdf: 594987 bytes, checksum: 801284de16c0bc1061e1e5c818193389 (MD5) Previous issue date: 2022

The delivery of nucleic acids to cells is considered a crucial step for the success of genetic modifications aimed at therapeutic purposes or production of genetically modified animals. In this context, nanotechnology is one of the most promising fields of science, with the potential to solve several existing problems. Nanostructures have desirable characteristics to be used as carriers, such as nanometric size, large surface area, cell internalization capacity, prolonged and controlled release, among others. Genetically modified animals can contribute to the production of biopharmaceuticals, through the expression of high-associated-value molecules. The production of these animals, also known as biofactories, further enhances Brazilian agribusiness, since it allows adding value to the final product, and favors the integration between the agricultural market and the pharmaceutical sector. However, there is a growing concern about the safety and possible harmful effects of nanostructures, since data on the safe use of these materials are still insufficient. The objective of this review was to address aspects of the use of nanostructures, mainly carbon nanotubes as nucleic acid carriers, aiming at the production of genetically modified animals, with the certainty that progress in this field of knowledge depends on more information on the mechanisms of interaction between nanostructures, cells and embryos, as well as on its toxicity. Made available in DSpace on 2022-05-10T16:12:42Z (GMT). No. of bitstreams: 1 Challenges-use-nanostructures.pdf: 603206 bytes, checksum: 533820a862c7319ede6a9cab4fb3fa87 (MD5) Previous issue date: 2022

This study aimed to evaluate the chemical composition and fatty acid (FA) profile of forage and silage of a seed-propagated elephant grass genotype called “PCEA” harvested at 75, 90, 105 and 120 days of regrowth. A randomized block design with five replications was used. The results were analyzed by mixed models (P < 0.05) that included treatment (regrowth age) as a fixed effect and block as a random effect. Linear and quadratic effects of the treatments were analyzed using orthogonal contrasts. There was linear increase on total dry matter (DM) forage production and linear decrease on leaf:stem ratio as a function of the increase in regrowth age (P < 0.05). In response to the advance of regrowth age, “PCEA” forage and silage showed linear decreases on crude protein (CP) content (g kg-1 DM) and in vitro DM digestibility (g kg-1); and linear increases on DM (g kg-1), lignin (g kg-1 DM), and acid detergent insoluble protein (%CP) contents (P < 0.05). All “PCEA” silages had DM content < 200 g kg-1, pH > 4.0, and ammonia N content > 10% total N. In response to the advance of regrowth age, linear decreases (P < 0.05) were observed on forage and silage linoleic, alfa-linolenic, and total FA contents (g kg-1 DM). From 75 to 120 days of regrowth, the seed-propagated elephant grass genotype “PCEA” presents forage and silage with low nutritional quality for feeding dairy cattle, moderate to high linoleic acid contents, and moderate to low alfa-linolenic acid contents. The “PCEA” forage and silage obtained from 75 to 120 days of regrowth presents low potential for production of milk naturally enriched with bioactive FAs beneficial to human health. Objetivou-se por meio deste estudo avaliar a composição química e o perfil de ácidos graxos (AG) da forragem e da silagem de um genótipo de capim-elefante propagado por sementes denominado “PCEA”, colhido aos 75, 90, 105 e 120 dias de rebrota. O delineamento experimental foi em blocos casualizados com cinco repetições, sendo os resultados analisados por modelos mistos (P < 0,05), que incluíram tratamento (idade de rebrota) como efeito fixo, e bloco como efeito aleatório. Os efeitos lineares e quadráticos dos tratamentos foram analisados por contrastes ortogonais. Houve aumento linear na produção total de matéria seca (MS) de forragem e decréscimo linear na relação folha:colmo, em função do aumento na idade de rebrota do capim (P < 0,05). Em resposta ao avanço na idade de rebrota, houve redução linear no teor de proteína bruta (PB) (g kg-1 MS) e na digestibilidade in vitro da MS (g kg-1); e aumento linear nos teores de MS (g kg-1), lignina (g kg-1 MS) e proteína insolúvel em detergente ácido (% da PB) da forragem e da silagem de “PCEA” (P < 0,05). Todas as silagens produzidas apresentaram teor de MS < 200 g kg-1, pH > 4,0 e teor de N amoniacal > 10% do N total. Em resposta ao avanço da idade de rebrota, decréscimos lineares (P < 0,05) foram observados nos teores (g kg-1 MS) dos ácidos linoleico, alfa-linolênico e AG totais. De 75 a 120 dias de rebrota, o genótipo de capim-elefante propagado por sementes “PCEA” apresenta forragem e silagem com baixa qualidade nutricional para alimentação do gado leiteiro, com moderado a alto teor de ácido linoleico, e moderado a baixo teor de ácido alfa-linolênico. A forragem e a silagem do “PCEA” obtidas de 75 a 120 dias de rebrota apresentam baixo potencial para produção de leite naturalmente enriquecido com AG bioativos benéficos à saúde humana.

We aimed to determine the energy requirements for maintenance and gain of 18 prepubertal dairy heifers of three breed compositions (BC; Holstein, Gyr, and Holstein × Gyr). Diets were formulated for gains of 0, 400, and 800 g/day, corresponding to 1.0×, 1.5×, and 2.0× maintenance, respectively. Each dairy BC had six animals with an initial body weight (iBW) of 219.8 ± 32 kg, 215.8 ± 33 kg, and 228.3 ± 33 kg for Holstein, Gyr, and Holstein × Gyr, respectively. The experiment was designed as a completely randomized design in a factorial scheme 3 × 3 [three BC and three feeding levels (FL)]. Digestibility and metabolism assays were performed to determine energy losses through feces and urine. Heat production was determined using the continuous measurement of oxygen consumption, carbon dioxide production, and methane emissions in respiration chambers. Energy requirements for maintenance (NEm) were calculated based on the relationship between heat production (HP) and metabolizable energy intake (MEI). The efficiency of use of metabolizable energy for maintenance (km) was obtained from the ratio between NEm and metabolizable energy requirements for maintenance. The net energy requirements for growth (NEg) were estimated from the model RE = β0 × EBW0.75 × EBGβ1, where RE is the retained energy (Mcal/day), EBW is empty body weight (kg0.75), and EBG is the empty body gain (kg/day). The efficiency of use of metabolizable energy for gain (kg) was estimated as the slope of the regression between RE and MEI for gain. Gyr heifers presented NEm 15% lower (98 kcal/kg of BW0.75) than HG crossbred animals. Holstein and crossbred heifers had similar NEm, 102 and 112 kcal/kg of BW0.75, respectively. The km was 0.71, 0.74, and 0.75 for HG, Holstein, and Gyr, respectively. Net energy requirement for gain (NEg) did not differ across BC, and a single equation was fit for all BC: RE = 0.069 × BW0.75 × BGW0.852. A single kg of 0.65 was observed for all three BC. Breed composition affected the energy requirements for maintenance and the energy partition, and those differences should be considered when estimating requirements for Gyr, Holstein × Gyr crossbred, and Holstein heifers.

The objective of this work was to evaluate the effects of breed and heterosis on the estimates of genetic parameters of 305-day milk yield (305MY), by fitting milk yield data to the Wood, Mixed Log, Morgan, and Wilmink non-linear models. A total of 258,891 test-day milk yield records of 37,965 Holstein (H), Gyr (G), and Girolando (1/2 H, 1/4 H, 3/4 H, 3/8 H, 5/8 H and 7/8 H genetic groups) cows from 1840 herds were collected in the state of Minas Gerais, Brazil, in the period of 1998 to 2014. The pedigree file included 36,640 animals, 3677 bulls and 24,472 cows. The genetic parameters were obtained by one-character analysis using the AIREMLF90 software. The heritability estimates of 305MY, and of 305MY fitted to the different nonlinear models ranged from 0.14 to 0.20. Most genetic groups had heterosis effect, with the greatest effects for 305MY on 1/2 H (1/2 Holstein × 1/2 Gyr) cows, presenting a milk yield of 1112.73 kg higher than the average of their parents. The results indicate that most genetic groups of Girolando present heterosis effect for 305MY estimated through nonlinear models, and the possibility of obtaining moderate genetic gains when these animals are subjected to selection procedures.HIGHLIGHTS The use Girolando cows in production systems in Brazil has shown positive results of production. This greater productive efficiency may be because of heterosis on the production and adaptation of these animals. The effect of breed and heterosis can be included in traditional models for the improvement of selection.

Simple Summary Waste milk (WM) is commonly used in the feeding of calves. Due to its legal prohibition in commercialization, the destination of WM has become an environmental issue for dairy farms. Many dairy farms pasteurize WM, focusing on reducing the microbial load and related sanitary challenges. However, pasteurized milk may still contain toxins of bacterial origin, spores, and antibiotic residues. Few studies have evaluated the effects of whole milk, WM, and pasteurized WM (PWM) on the intake, ruminal parameters, blood parameters, health, and performance of dairy calves. In our study, feeding WM or PWM did not show significant negative effects on the intake, ruminal parameters, blood parameters, health, or performance of dairy calves. Understanding the effects of using WM and PWM on the health and performance of dairy calves requires further investigation. Abstract The aim of this study was to evaluate the effects of bulk tank milk (BTM), WM, and PWM on the intake, ruminal parameters, blood parameters, health, and performance of dairy calves. Forty-five male crossbred dairy calves (Gyr × Holstein) were used. On their fourth day of age, animals were grouped according to body weight, serum protein levels, and genetic composition. Three treatments were assessed: BTM (n = 15), WM from cows in antibiotic treatment (n = 15), and PWM via high-temperature, short-time pasteurization (72–74 °C for 16 s) (n = 15). During the experimental period (from 4 to 60 d of age), animals were fed 6 L of milk/d, divided into two equal meals. Water and concentrate were provided ad libitum. Daily measurements were made for milk, concentrate, and water intakes, as well as for fecal and respiratory scores. Rumen fluid and blood were sampled weekly. The following parameters were evaluated: volatile fatty acids (VFAs), pH and ammonia-N in rumen fluid, and β-hydroxybutyrate (BHB) and glucose in blood. Animals were weighed at birth, 4 d of age, and weekly up to 60 d of age. At the end of the experimental period (60 ± 1 d), all animals were euthanized for pulmonary evaluation. The randomized complete design with an interaction between treatment and week was the experimental method of choice for testing the hypothesis of the treatment’s effect on all evaluated outcomes. Animals in the BTM treatment had higher milk dry matter intake (DMI), followed by WM and PWM calves. Concentrate DMI was lower for BTM in comparison to WM and PWM calves. However, total DMI showed no significant differences between treatments. The rumen fluid from calves receiving PWM had higher concentrations of acetate and propionate than that of BTM and WM animals. No differences were observed between treatments for blood glucose and BHB concentrations. Health parameters (fecal and respiratory scores) and pneumonia occurrence showed no significant difference between treatments. No differences were observed for average daily gain (ADG) or body growth. Feeding WM and PWM did not show significant negative effects on the intake, ruminal parameters, blood parameters, health, or performance of dairy calves.

Simple Summary Understanding the perception of dairy farmers regarding precision livestock technologies is crucial for creating strategic actions that will increase the rate of adoption and usage of such technologies. A survey study was applied to 378 dairy farms located in Brazil. The farmers were characterized based on technology usage, farmer profile, farm characteristics, and production indexes. The farms were classified into seven clusters: (1) top yield farms; (2) medium–high yield, medium-tech; (3) medium yield and top high-tech; (4) medium yield and medium-tech (5); young medium–low yield and low-tech; (6) elderly medium–low yield and low-tech; and (7) low-tech grazing. Our study helped to elucidate the farmer’s perception about precision technologies and to shed light on challenges that need to be addressed by scientific research and extension programs. Abstract The use of precision farming technologies, such as milking robots, automated calf feeders, wearable sensors, and others, has significantly increased in dairy operations over the last few years. The growing interest in farming technologies to reduce labor, maximize productivity, and increase profitability is becoming noticeable in several countries, including Brazil. Information regarding technology adoption, perception, and effectiveness in dairy farms could shed light on challenges that need to be addressed by scientific research and extension programs. The objective of this study was to characterize Brazilian dairy farms based on technology usage. Factors such as willingness to invest in precision technologies, adoption of sensor systems, farmer profile, farm characteristics, and production indexes were investigated in 378 dairy farms located in Brazil. A survey with 22 questions was developed and distributed via Google Forms from July 2018 to July 2020. The farms were then classified into seven clusters: (1) top yield farms; (2) medium–high yield, medium-tech; (3) medium yield and top high-tech; (4) medium yield and medium-tech; (5) young medium–low yield and low-tech; (6) elderly medium–low yield and low-tech; and (7) low-tech grazing. The most frequent technologies adopted by producers were milk meters systems (31.7%), milking parlor smart gate (14.5%), sensor systems to detect mastitis (8.4%), cow activity meter (7.1%), and body temperature (7.9%). Based on a scale containing numerical values (1–5), producers indicated “available technical support” (mean; σ2) (4.55; 0.80) as the most important decision criterion involved in adopting technology, followed by “return on investment—ROI” (4.48; 0.80), “user-friendliness” (4.39; 0.88), “upfront investment cost” (4.36; 0.81), and “compatibility with farm management software” (4.2; 1.02). The most important factors precluding investment in precision dairy technologies were the need for investment in other sectors of the farm (36%), the uncertainty of ROI (24%), and lack of integration with other farm systems and software (11%). Farmers indicated that the most useful technologies were automatic milk meters systems (mean; σ2) (4.05; 1.66), sensor systems for mastitis detection (4.00; 1.57), automatic feeding systems (3.50; 2.05), cow activity meter (3.45; 1.95), and in-line milk analyzers (3.45; 1.95). Overall, the concerns related to data integration, ROI, and user-friendliness of technologies are similar to those of dairy farms located in other countries. Increasing available technical support for sensing technology can have a positive impact on technology adoption.