Influence of Molybdenum and Organic Sources of Copper and Sulfur on the Performance, Carcass Traits, Blood Mineral Concentration, and Ceruloplasmin Activity in Lambs.

This study aimed to evaluate the effects of molybdenum (Mo) and organic and inorganic sources of copper (Cu) and sulfur (S) on the performance, carcass traits, and blood concentration of these minerals in lambs. Forty male non-castrated crossbred Dorper x Santa Inês lambs (20 ± 1.2 kg of body weight and 90 ± 2 d of age) were randomly allocated into one of the ten following treatments: (T0) control, basal diet; (T1) Mo; (T2) inorganic Cu and inorganic S; (T3) inorganic Cu and organic S; (T4) organic Cu and inorganic S; (T5) organic Cu and organic S; (T6) Mo plus inorganic Cu and inorganic S; (T7) Mo plus inorganic Cu and organic S; (T8) Mo plus organic Cu and inorganic S; and (T9) Mo plus organic Cu and organic S. Regardless of the source, Mo, Cu, and S were added at levels of 10 mg, 10 mg, and 2000mg/kg DM, respectively. The mineral supplements (Mo, Cu, and S) were added into the total mixed ration (TMR) by mixing them apart with the mineral and vitamin premix and then put into the TMR. The animals were kept in individual pens and received a total mixed ration for 84 days. Body weight and blood sampling was performed every 28 days. All animals were slaughtered after 84 days, and carcass traits were evaluated. Although organic sources of Cu and S added to Mo supplementation had increased the ADG throughout the study, this effect did not reflect in the heavier final BW outcomes for this treatment. In addition, no effect of these treatments was observed on the carcass traits. The serum Cu concentration was higher for the T0 group compared to the other groups; otherwise, Mo reduced the serum Cu concentration compared to the other groups. Considering the interaction among the minerals and their sources at 84 d of study, organic sources of Cu and S treatment and Mo associated with inorganic sources of Cu plus organic S treatment had an increased serum Cu concentration compared to other groups. Regardless of time, organic sources of Cu and S increased serum S concentration. At 84 days after enrollment, serum Mo concentration was lower for the control group compared to the other groups. Further, Mo supplementation increased its blood concentration compared to the control group throughout the study. The control group had the highest ceruloplasmin activity compared to the other groups; otherwise, at 84 d of the study, either Mo or inorganic S supplementation reduced ceruloplasmin activity. Serum ceruloplasmin activity was higher when Cu supplementation, regardless of source, was associated with organic S. However, at d 84 of the study, inorganic Cu associated to organic S supplements increased serum ceruloplasmin activity. In this current study, it was not possible to identify a pattern in the variables studied, however, further studies are needed to confirm that organic sources of Cu and S interacted alone without a defined pattern.

Pigeon Pea Intercropped with Tropical Pasture as a Mitigation Strategy for Enteric Methane Emissions of Nellore Steers.

In this study, we evaluate the effects of intercropping pigeon pea (Cajanus cajan (L.) Millsp.) with tropical pastures for feeding Nellore cattle and compared animal performance and enteric CH4 emissions with other pasture-based systems during the dry and rainy seasons of 2021. Thirty-six Nellore steers (with a body weight of 221 ± 7 kg and an age of 15-16 months) were randomly distributed in three treatments with three replicates (in paddocks of 1.5 hectares each): (1) a degraded pasture of Urochloa spp. (DEG); (2) a recovered and fertilized pasture of Urochloa spp. (REC); and (3) pigeon pea intercropped with Urochloa spp. (MIX). Enteric CH4 emissions were estimated using the sulfur hexafluoride (SF6) tracer gas technique, and dry matter intake (DMI) was determined using internal (iNDF) and external (TiO2) markers. Forages were collected by hand plucking after observations of ingestive behavior, and feces was collected after voluntary defecation. The proportion of grass and legume intake was estimated by C stable isotopes, and the forage nutritional quality was determined, while animal performance was monitored monthly, and the stocking rate was adjusted by the "put and take" technique. The results indicated that intercropping pigeon pea with tropical grasses is an interesting strategy for sustainable livestock production based on pastures. The MIX treatment was able to meet the nutritional requirements of the animals, which presented higher performance. In addition, there was a reduction in CH4 emissions up to 70% when expressed per average daily weight gain in comparison to the DEG treatment.

Greenhouse gas balance and mitigation of pasture-based dairy production systems in the Brazilian Atlantic Forest Biome.

Brazilian cattle production is mostly carried out in pastures, and the need to mitigate the livestock's greenhouse gas (GHG) emissions and its environmental footprint has become an important requirement. The adoption of well-suited breeds and the intensification of pasture-based livestock production systems are alternatives to optimize the sector's land use. However, further research on tropical systems is necessary. The objective of this research was to evaluate the effect of Holstein (HO) and Jersey-Holstein (JE x HO) crossbred cows in different levels of pasture intensification (continuous grazing system with low stocking rate-CLS; irrigated rotational grazing system with high stocking rate-RHS), and the interaction between these two factors on GHG mitigation. Twenty-four HO and 24 JE x HO crossbred dairy cows were used to evaluate the effect of two grazing systems on milk production and composition, soil GHG emissions, methane (CH4) emission, and soil carbon accumulation (0-100 cm). These variables were used to calculate carbon balance (CB), GHG emission intensity, the number of trees required to mitigate GHG emission, and the land-saving effect. The number of trees necessary to mitigate GHG emission was calculated, considering the C balance within the farm gate. The mitigation of GHG emissions comes from the annual growth rate and accumulation of C in eucalyptus trees' trunks. The CB of all systems and genotypes presented a deficit in carbon (C); there was no difference for genotypes, but RHS was more deficient than CLS (-4.99 to CLS and -28.72 to RHS ton CO2e..ha-1.year-1). The deficit of C on GHG emission intensity was similar between genotypes and higher for RHS (-0.480 to RHS and -0.299 to CLS kg CO2e..kg FCPCmilk-1). Lower GHG removals (0.14 to CLS higher than 0.02 to RHS kg CO2e..kg FCPCmilk-1) had the greatest influence on the GHG emission intensity of milk production. The deficit number of trees to abatement emissions was higher to HO (-46.06 to HO and -38.37 trees/cow to JE x HO) and to RHS (-51.9 to RHS and -33.05 trees/cow to CLS). However, when the results are expressed per ton of FCPCmilk, there was a difference only between pasture management, requiring -6.34 tree. ton FCPCmilk-1 for the RHS and -3.99 tree. ton FCPCmilk-1 for the CLS system. The intensification of pastures resulted in higher milk production and land-saving effect of 2.7 ha. Due to the reservation of the pasture-based dairy systems in increasing soil C sequestration to offset the GHG emissions, especially enteric CH4, planting trees can be used as a mitigation strategy. Also, the land-save effect of intensification can contribute to the issue, since the area spared through the intensification in pasture management becomes available for reforestation with commercial trees.

Two Hours of Separation Prior to Milking: Is This Strategy Stressful for Jennies and Their Foals?

The goal of this study was to assess whether or not a separation period of 2 h is stressful for jennies and foals, as measured by changes in behaviour, salivary cortisol, and milk production. This study was reviewed and approved by the Committee for the Use and Care of Animals in Research (CEUA) of the School of Veterinary Medicine and Animal Science of the University of São Paulo. Fourteen multiparous Pêga jennies (245 kg average body weight) and their foals were assessed from day 45 to 135 of lactation. Dams and foals were separated for 2 h prior to milking. Behavioural assessments and saliva samples were collected before and after separation, every 15 days, resulting in 14 samples per individual animal. Behavioural states (affiliative and inactivity) and events (agonistic, abnormal, eliminative and vocalisations) of the jennies were observed during 6 min in both periods. Moreover, milk yield was measured. Few significant behavioural and salivary cortisol changes were observed, and milk yield was not affected by cortisol levels in response to the separation. The 2-h separation period, on the basis of the collected variables, did not appear to be stressful for the assessed group of Pêga jennies or foals; however, their ability to adapt to milking routine stress remains to be investigated.

Evaluation of liquid and powdered forms of polyclonal antibody preparation against Streptococcus bovis and Fusobacterium necrophorum in cattle adapted or not adapted to highly fermentable carbohydrate diets.

OBJECTIVE: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet. METHODS: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly. RESULTS: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals. CONCLUSION: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

Mini review on photosensitization by plants in grazing herbivores.

Photosensitization is severe dermatitis or oxidative/chemical changes in the epidermal tissues activated by the light-induced excitation of molecules within the tissue. It is a series of reactions mediated through light receptors and is more common when the plant-produced metabolites are heterocyclic/polyphenols in nature. The areas affected are exposed body parts and mostly non-pigmented areas with least ultraviolet protection. Similarly, cellular alteration also occurs in the affected animal's dermal tissues and body parts and grazing animals by the accumulation and activation of photodynamic molecules. Photo-oxidation can also occur within the plant due to the generation of reactive oxygen species causing damage and degradation in the form of free radicals and DNA. During the last few decades, many new tropical grass species have been introduced in the grazing lands which are genetically modified, and the animals grazing on them are facing various forms of toxicity including photosensitization. The plant's secondary metabolites/drugs may cause toxicity when bacteria, viral agents, fungi (Pithomyces chartarum), or neoplasia injures the liver and prevents the phylloerythrin excretion. All these may disturb the liver enzymes and blood profile causing a decrease in weight and production (wool and milk etc.) with severe dermal, digestive, and nervous problems. Recent advancements in OMICS (cellomics, ethomics, metabolomics, metabonomics, and glycomics) have enabled us to detect and identify the plants' secondary metabolites and changes in the animal's physiology and histopathology as a causative of photosensitivity. The review focuses on types of photosensitization, reasons, secondary metabolic compounds, chemistry, and environmental effect on plants.

Slow-release urea in supplement fed to beef steers

Replacing regular urea (RU) by slow-release urea (SRU) at two levels of non-protein nitrogen (NPN) in concentrate, offered with low-quality roughage, was evaluated in beef steers on dry matter intake (DMI), ruminal fermentation parameters, plasma urea nitrogen (PUN), total tract apparent digestibility of diets and in situ degradability of nitrogen sources. Eight ruminally cannulated steers were allocated into two 4x4 Latin squares, totalizing four treatments: 40 NPN/0 SRU: 40% of concentrate crude protein (CP) as NPN, resulting from 0% of SRU and 100% of RU; 40 NPN/50 SRU: 40% of concentrate CP as NPN, resulting from 50% of SRU and 50% of RU; 40 NPN/100 SRU: 40% of concentrate CP as NPN, resulting from 100% of SRU and 0% of RU; 80 NPN/100 SRU: 80% of concentrate CP as NPN, resulting from 100% of SRU and 0% of RU. Results showed that partial substitution of regular urea by slow-release urea did not alter dry matter intake, pattern of ruminal fermentation or plasma urea nitrogen concentrations and increased the total tract apparent digestibility of crude protein in steers diets. The increase in non-protein nitrogen content in crude protein of the concentrate could compromise feed intake and the efficiency of nutrient utilization in the steers fed complete diets based on low quality forage.

Metabolic profile and ruminal and abomasal pH in sheep subjected to intravenous ranitidine / Perfil metabólico ruminal e pH abomasal em ovinos tratados com ranitidina por via intravenosa

Brazilian sheep production has intensified, predisposing sheep to an increased incidence of digestive disorders, such as abomasal ulcers. Ranitidine is used to prevent and treat this disease; however, there is little information on the parenteral use of this drug in adult ruminants. Few data exist on the concomitant metabolic changes and the behavior of the digestive system associated with its use. For this study, five healthy male sheep with ruminal and abomasal cannulas were used. A 5x5 Latin square experiment with a 2x2+1 factorial arrangement of the treatments was performed. Sheep treated with drug doses of 1 or 2mg/kg ranitidine administered intravenously every 8 or 12 hours were compared with the control group, was treated intravenously with 1 mL of physiological solution per 25 kg every 12 hours. Higher total protein concentrations, hemoglobin levels, as well as increased aspartate aminotransferase activity and increased abomasal pH for up to 150 min following drug administration were observed in all animals that received the drug, regardless of dose and frequency. The animals treated every 12 hours showed a decrease in leukocyte number compared with the control group and with the animals treated every 8 hours. Increased serum creatinine concentrations were observed in the animals treated every 8 hours. Treatments of 1mg/kg every 8 hours and 2mg/kg every 12 hours increased the red blood cell count and decreased the serum pepsinogen. All protocols studied were safe for healthy sheep, but 1mg/kg ranitidine every 8 hours and 2mg/kg ranitidine every 12 hours were the most effective protocols for gastric protection.(AU)

A ovinocultura brasileira tem se intensificado, o que predispõe os animais à maior incidência de transtornos digestivos, como a úlcera de abomaso. A ranitidina é utilizada na prevenção e tratamento desta afecção, no entanto há pouca informação sobre a indicação parenteral deste fármaco para ruminantes adultos. São escassas as informações a respeito das alterações metabólicas e do comportamento do sistema digestório associados ao seu uso. Para este estudo foram utilizados cinco ovinos, machos, hígidos, providos de cânula ruminal e abomasal. O delineamento foi Quadrado Latino 5x5 com arranjo fatorial de tratamentos 2x2+1. Os ovinos tratados com as doses de 1 e 2mg/kg de ranitidina administrada por via intravenosa a cada 8 ou 12 horas foram comparados aos animais do grupo controle, tratados por via intravenosa com 1mL de solução fisiológica por 25 kg a cada 12 horas. Maiores concentrações de proteína total e hemoglobina, maiores atividades de AST e aumento do pH abomasal por até 150 minutos foram observados em todos os animais que receberam o fármaco, independentemente de dose e frequência. Os animais tratados a cada 12 horas mostraram diminuição do número de leucócitos comparados aos animais tratados a cada 8 horas e aos animais do grupo controle. Observou-se aumento das concentrações de creatinina nos animais tratados a cada 8 horas. Os tratamentos 1mg/kg a cada 8 horas e 2mg/kg a cada 12 horas aumentaram o número de hemácias e diminuíram as concentrações séricas de pepsinogênio. Todos os protocolos estudados foram seguros para ovinos sadios, porém 1mg/kg de ranitidina a cada 8 horas e 2mg/kg a cada 12 horas mostraram-se mais eficientes quanto à proteção gástrica.

Características fermentativas de silagens de cana-de-açúcar com erva-sal / Fermentation characteristics of sugarcane silages with saltbush

Objetivou-se com o presente estudo avaliar diferentes níveis (0, 20, 40 e 60%) de inclusão de erva-sal na dinâmica fermentativa da silagem de cana-de-açúcar. Utilizou-se delineamento experimental inteiramente casualizado com quatro tratamentos e seis repetições. Após 90 dias, com a abertura dos silos, determinou-se os teores de carboidratos solúveis (CHO-Sol), etanol, ácidos orgânicos (lático, acético, propiônico, butírico), proteína bruta (PB), matéria mineral (MM), matéria seca (MS), fibra em detergente neutro livre de cinzas (FDNc), pH e poder tampão (PT); estimou-se a perda total de MS, perdas por efluente e gases, densidade e a recuperação da MS. Os níveis crescentes de erva-sal propiciaram diminuição das perdas totais de MS e por efluente, aumento de seu teor e recuperação desta. As silagens apresentaram pH adequado à conservação (≤3,70) e concentração de minerais acrescidos. As concentrações de etanol foram influenciadas (P<0,05) pelo incremento de erva-sal, em que se observou redução de 51,84%, com 40% de erva-sal na silagem de cana. A adição de erva-sal reduz as perdas de MS e a produção de etanol e, melhora a qualidade fermentativa da silagem de cana-de-açúcar.

The objective of this study was to evaluate different inclusion levels (0, 20, 40 and 60%) of old man saltbush in the fermentation dynamics of sugarcane silages. The experiment was carried out as a completely randomized design with four treatments and six replicates. After 90 days, with the opening of the silos, the levels of water soluble carbohydrates, ethanol, organic acids (lactic, acetic, propionic, butyric acid), crude protein (CP), mineral matter (MM), dry matter (DM), neutral detergent fiber ash free (NDFa), pH and buffer capacity were determined; and, the losses by gas, effluent and total of dry mater, density and dry matter recovery were estimated. Increasing levels of saltbush propitiated reduction in losses: by effluent and total dry matter, it also increased the concentration and recovery. The silages showed pH suitable for conservation (≤3.70) and mineral concentration increased. The ethanol concentrations were influenced (P<0.05) by the increase of saltbush, where reduction of 51.84% was observed, with 40% saltbush in sugarcane silage. The addition of saltbush reduces dry matter losses and ethanol production and, improves the quality of sugarcane silage.

Composição bromatológica e digestibilidade de cana-de-açúcar colhida em duas épocas do ano / Chemical composition and digestibility of sugarcane harvested at two periods of the year

Objetivou-se com este estudo avaliar o efeito da época de corte sobre a composição bromatológica e digestibilidade in vitro de genótipos de cana-de-açúcar, comparar a composição bromatológica e digestibilidade in vitro das frações colmo e folhas, e estabelecer possíveis correlações entre composição química e digestibilidade in vitro da planta inteira de genótipos da cana-de-açúcar. Nove genótipos foram colhidos em maio e setembro de 2006. Em maio, somente a fração planta inteira foi analisada, em setembro foram separados em colmos, folhas ou planta inteira para determinação da composição bromatológica, sacarose (POL) e digestibilidade in vitro. Colmos apresentaram menor teor de fibra em detergente neutro (FDN) e lignina na MS, e maior digestibilidade in vitro da matéria seca (DIVMS) do que folhas. Em contrapartida, apresentaram menor digestibilidade in vitro da FDN (DIVFDN), maior teor de lignina na FDN e menor concentração de proteína bruta (PB). Houve redução no teor e digestibilidade da FDN com o avanço da maturidade, enquanto que DIVMS, POL e lignina aumentaram. A DIVMS se mostrou negativamente correlacionada com FDN e FDN/POL, porém não houve correlação entre DIVFDN e FDN ou FDN/POL. Conclui-se que o avanço da maturidade promoveu redução na DIVFDN e aumento na DIVMS, não existindo correlação genética entre acúmulo de açúcar e digestibilidade in vitro da fibra. Os dados deste artigo indicam não ser esperado que a seleção de genótipos com maior DIVFDN do colmo altere o teor de açúcar do mesmo.

The objectives of this study were to evaluate the effect of time of harvest on chemical composition and in vitro digestibility of sugarcane genotypes, to compare chemical composition and in vitro digestibility of the stem and leaf fractions, and to determine possible correlations between chemical composition and in vitro digestibility of the whole plant in sugarcane genotypes. Nine genotypes were harvested in May and September of 2006. In May, only the whole-plant fraction was analyzed, in September the genotypes were separated in stems, leaves or whole-plant for determination of chemical composition, sucrose (POL) and in vitro digestibility. Stems had lower neutral detergent fiber (NDF) and lignin in the DM, and greater in vitro dry matter digestibility (IVDMD) than leaves. However, stems had lower in vitro NDF digestibility (IVNDFD), higher lignin in the NDF and lower crude protein (CP). The NDF and IVNDFD were reduced with advanced maturity, while IVDMD, POL and lignin were increased. IVDMD was negatively correlated with NDF and NDF/POL, however there was no correlation between IVFDND and NDF or NDF/POL. It can be concluded that with the advance in maturity the IVNDFD was reduced and IVDMD was increased, and there was no genetic correlation between accumulation of sugar and in vitro fiber digestibility. Data from this study indicate that it is not expected that selection of genotypes with greater stem IVNDFD would alter the sugar content of the plant.

Composição bromatológica e digestibilidade de cana-de-açúcar colhida em duas épocas do ano / Chemical composition and digestibility of sugarcane harvested at two periods of the year

Objetivou-se com este estudo avaliar o efeito da época de corte sobre a composição bromatológica e digestibilidade in vitro de genótipos de cana-de-açúcar, comparar a composição bromatológica e digestibilidade in vitro das frações colmo e folhas, e estabelecer possíveis correlações entre composição química e digestibilidade in vitro da planta inteira de genótipos da cana-de-açúcar. Nove genótipos foram colhidos em maio e setembro de 2006. Em maio, somente a fração planta inteira foi analisada, em setembro foram separados em colmos, folhas ou planta inteira para determinação da composição bromatológica, sacarose (POL) e digestibilidade in vitro. Colmos apresentaram menor teor de fibra em detergente neutro (FDN) e lignina na MS, e maior digestibilidade in vitro da matéria seca (DIVMS) do que folhas. Em contrapartida, apresentaram menor digestibilidade in vitro da FDN (DIVFDN), maior teor de lignina na FDN e menor concentração de proteína bruta (PB). Houve redução no teor e digestibilidade da FDN com o avanço da maturidade, enquanto que DIVMS, POL e lignina aumentaram. A DIVMS se mostrou negativamente correlacionada com FDN e FDN/POL, porém não houve correlação entre DIVFDN e FDN ou FDN/POL. Conclui-se que o avanço da maturidade promoveu redução na DIVFDN e aumento na DIVMS, não existindo correlação genética entre acúmulo de açúcar e digestibilidade in vitro da fibra. Os dados deste artigo indicam não ser esperado que a seleção de genótipos com maior DIVFDN do colmo altere o teor de açúcar do mesmo.

The objectives of this study were to evaluate the effect of time of harvest on chemical composition and in vitro digestibility of sugarcane genotypes, to compare chemical composition and in vitro digestibility of the stem and leaf fractions, and to determine possible correlations between chemical composition and in vitro digestibility of the whole plant in sugarcane genotypes. Nine genotypes were harvested in May and September of 2006. In May, only the whole-plant fraction was analyzed, in September the genotypes were separated in stems, leaves or whole-plant for determination of chemical composition, sucrose (POL) and in vitro digestibility. Stems had lower neutral detergent fiber (NDF) and lignin in the DM, and greater in vitro dry matter digestibility (IVDMD) than leaves. However, stems had lower in vitro NDF digestibility (IVNDFD), higher lignin in the NDF and lower crude protein (CP). The NDF and IVNDFD were reduced with advanced maturity, while IVDMD, POL and lignin were increased. IVDMD was negatively correlated with NDF and NDF/POL, however there was no correlation between IVFDND and NDF or NDF/POL. It can be concluded that with the advance in maturity the IVNDFD was reduced and IVDMD was increased, and there was no genetic correlation between accumulation of sugar and in vitro fiber digestibility. Data from this study indicate that it is not expected that selection of genotypes with greater stem IVNDFD would alter the sugar content of the plant.

Effects that bovine sperm cryopreservation using two different extenders has on sperm membranes and chromatin.

The process of cryopreservation impairs sperm cell function, potentially leading to a reduction in fertility. The objectives of the present study were to evaluate the effects that cryopreservation using two different extenders has on sperm motility and mitochondrial function, as well as on the integrity of plasma membranes, acrosomal membranes and chromatin, using practical and objective techniques. The focus of the present study was to identify correlations between alterations in sperm membranes and sperm motility in cryopreserved bovine spermatozoa. Seven ejaculates were collected from eight Simmental bulls (n=56). After collection, semen volume and concentration were assessed for purposes of dilution. Sperm motility was evaluated subjectively and by computer-assisted semen analysis, morphological characteristics were evaluated by differential interference microscopy, the integrity of plasma and acrosomal membranes, as well as mitochondrial function, were determined using a combination of fluorescent probes containing fluorescein isothiocyanate-Pisum sativum agglutinin, propidium iodide or 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide. Chromatin integrity was evaluated using the acridine orange technique. The semen was subsequently divided into two aliquots and diluted with one of two extenders (Bioxcell or Botu-Bov), after which both were packaged in 0.5 mL straws and frozen using an automated system. Two straws of semen from each treatment were thawed, and the semen parameters were evaluated as described above. Cryopreservation of sperm reduced motility, damaging plasma and acrosomal membranes, as well as decreasing mitochondrial function. The Botu-Bov extender was more effective in preserving sperm motility and membrane integrity than was the Bioxcell extender.

Parâmetros fisiológicos do desempenho de cavalos de alta performance hidratados voluntariamente com água ou solução isotônica contendo carboidrato / Physiological parameters of high performance horses watered spontaneously with regular (ordinary) water or isotonic solution containing carbohydrate

Durante 8 semanas, no verão, 4 cavalos de alta performance treinados para enduro, realizaram exercício de resistência recebendo 2 tipos diferentes de hidratação, água ou solução isotônica contendo carboidrato, com o objetivo de comparar seus parâmetros fisiológicos. Somente as variáveis Tr, Fc, Fr, peso e proteína total, consumo, glicose, os eletrólitos K, Ca e a enzima muscular CK apresentaram efeito de distância. Dos demais parâmetros avaliados não foram identificados os efeitos de tratamento e de interação da distância com o tratamento estudado (P>0,05), concluindo assim que a solução isotônica contendo carboidrato não teve influencia na performance dos animais, quando comparada com a água.

During eight weeks, in summer, four endurance trained high performance horses were worked in resistence exercise, recieving two different types of hydratatio, water or an isotonic solution containing carbohydrates, with the objective to compare their performance physiological parameters. Only the RT (rectal temperature), HR (heart rate), RR (respiratory rate), weight, total protein, glucose, the electrolytes K, Ca and the muscular enzyme CK presented distance effect. The others parameters evaluated, there weren’t any identified effects of treatment and of the interaction between distance and treatments, with a significancy level of 5%, and it was concluded that the isotonic solution containing carbohydrate didn’t have any significant influence on the animal’s performance when compared to water.

Uso do hCG, GnRH ou 17beta-Estradiol e progesterona associados ao acetato de melengestrol e prostaglandina f2alfa em novilhas cruzadas (Bos taurus indicus x Bos taurus taurus) / Use of hCG, GnRH or 17beta-estradiol and progesterone associated with melengestrol acetate and prostaglandin F2alfa in cross-bred heifers (Bos taurus indicus x Bos taurus taurus)

O objetivo do presente experimento foi avaliar a performance reprodutiva e as características de estros em novilhas cruzadas de corte (Bos taurus indicus x Bos taurus taurus) tratadas com o protocolo MGA/Prostaglandina (PG) em associação a outros hormônios. No dia 0 (Dia 0 = início da ingestão do MGA) as novilhas foram distribuídas ao acaso para receber 2mL de solução salina (grupo Salina), 2500UI de hCG (grupo hCG), 20müg de acetato de buserelina (grupo GnRH) ou 5mg de 17beta-estradiol + 100mg de progesterona (grupo 17beta-E2 +P4. Amostras de sangue foram colhidas nos dias - 7, 0, 7 e 10 para a mensuração das concentrações plasmáticas de progesterona. Independentemente do tratamento, todas as novilhas receberam 0,5mg MGA/ animal/ dia durante 8 dias (Dia 0 ao 7) e PG (Dia 7). Os estros foram observados durante 120h, a partir da injeção de PG, pelo sistema Heat- Watch. As novilhas foram inseminadas 12 horas após o início dos estros ou 72h depois da injeção de PG. O diagnóstico de gestação foi realizado 35 dias após a última inseminação, por ultrasonografia. As respostas em estros foram de 50,0%, 22,2%, 59,5% e 71,8% para os grupos Salina, hCG, GnRH e 17beta-E2 +P4, respectivamente (P< ou =0,01). O intervalo médio da injeção de PG ao estro foi de 72,8 + ou - 22,2, 102,0 + ou - 22,7,84,6 + ou - 19,0 e 72,5 + ou - 24,4 horas (P< ou =0,01), sendo o grau de sincronização similar entre os grupos. As taxas de concepção foram de 57,9%, 37,5%, 40,9% e 39,3% e as taxas de prenhez de 29,0%, 11,1 %,27,0% e 28,2%, para os grupos Salina, hCG, GnRH e 17beta-E2 +P4, respectivamente. Não houve efeito do tratamento na duração dos estros (10,4 + ou - 5,7 horas), número de montas (23,0 + ou - 16,9) e duração das montas (2,7 + ou - 0,3 segundos), sendo os valores entre parênteses correspondentes às médias gerais e desvios padrão. Em conclusão, a performance reprodutiva não foi alterada pela adição do hCG, GnRH ou 17beta-E2 +P4 ao protocolo de sincronização MGA/PG.

Supplementation of dairy cows with propylene glycol during the periparturient period: effects on body condition score, milk yield, first estrus post-partum, beta-hydroxybutyrate, non-esterified fatty acids and glucose concentrations

O objetivo do presente estudo foi o de analisar os efeitos da suplementação de propilenoglicol (PPG) para vacas no período peri-parto sobre a produção de leite, mudanças no escore de condição corporal (ECC), número de dias para o primeiro cio pós-parto, concentrações plasmáticas de b-hidroxibutirato (BHBA), ácidos graxos não-esterificados (AGNE) e glicose. Vinte e três vacas da raça Holandesa foram alocadas em dois tratamentos: a) 300 mL de PPG (grupo tratamento, 11 vacas), b) 300 mL de água (grupo controle, 12 vacas), administrados através de beberagem no período peri-parto. Amostras de plasma foram coletadas durante os dias -10, -5, 0, 3, 7, 14, 21, 28, 35, 42 e 49 em relação à data do parto para análises de BHBA, AGNE e glicose. O ECC foi avaliado nos dias -10, 0, 15, 30, 45 e 60 em relação à data do parto. Não houve efeito do tratamento ou tempo sobre a produção de leite, embora a interação tempo*tratamento foi significativa, sendo que entre a 4ª e 5ª semana de lactação, a produção de leite foi significativamente maior para o grupo tratamento. Não houve efeito do tratamento sobre o ECC do parto até 60 dias de lactação. O número de dias para o primeiro cio pós-parto para o grupo PPG e controle foi em média 40,2 e 45,2, respectivamente. Não houve efeito do tratamento da interação tempo*tratamento sobre as concentrações plasmáticas de BHBA, AGNE e glicose, mas houve efeito do tempo sobre a concentração de glicose e AGNE. A suplementação de PPG apresenta efeito pouco importante na redução dos efeitos metabólicos negativos que ocorrem durante o início da lactação de vacas leiteiras.

Avaliaçäo da atividade da mieloperoxidase neutrofílica em bovinos da raça Holandesa e sua correlaçäo com níveis plasmáticos de ácido ascórbico / Evaluation of neutrophilic myeloperoxidase activity in Holstein cows and its correlation to plasma ascorbic acid levels

A mieloperoxidase (MPO) é uma enzima que desempenha papel fundamental nos mecanismos bactericidas dos mamíferos, sendo encontrada principalmente em leucócitos polimorfonucleares neutrófilos. A MPO está diretamente relacionada com os mecanismos bactericidas dependentes de O2, sendo catalisadora do processo de formaçäo de radicais altamente reativos como o ácido hipocloroso (HCLO), a partir de H2O2 e íons halogênios, constituindo, portanto, importante mecanismo de defesa contra microrganismos patogênicos. O ácido ascórbico apresenta efeitos estimulatórios sobre a atividade fagocitária de leucócitos, sobre a funçäo do sistema reticuloendotelial e sobre a síntese de anticorpos, além de estimular a atividade de MPO in vitro em humanos, aumentando a produçäo de HCIO. No homem, foi descrito um quadro de deficiência de MPO que leva à diminuiçäo da capacidade bactericida dos neutrófilos contra Staphylococcus aureus e Candida albicans, e também a uma maior susceptibilidade desses indivíduos às infecçöes em geral. Neste trabalho foram coletadas amostras de sangue de 100 vacas da raça Holandesa, distribuídas em diferentes estágios de lactaçäo e provenientes de três rebanhos comerciais. Utilizou-se o método de Kaplow, originalmente utilizado em humanos, para a avaliaçäo da atividade MPO de neutrófilos e a técnica de HPLC (®High Performance Liquid Chromatograph¼) para a determinaçäo dos níveis plasmáticos de ácido ascórbico. Os resultados da correlaçäo entre a atividade MPO e os níveis de ácido ascórbico foram analisados através do programa ®Computacional Statistical Analysis System¼ (SAS Institute Inc., 1985), mostrando associaçäo negativa entre a atividade enzimática da MPO e o nível plasmático de ácido ascórbico in vivo. Além disto, houve efeito significativo do número de lactaçöes sobre esta associaçäo.

Efeitos da lasalocida sódica e proporçäo volumoso/concentrados sobre a fermentaçäo ruminal em vacas secas / Effects of sodium lasalocid and roughage/concentrate ratio on ruminal fermentation in dry cows

Efeitos da lasalocida sódica e de diferentes proporçöes volumoso:concentrados foram estudados em experimento em Quadrado Latino 4 x 4, utilizando-se quatro fêmeas bovinas (500 kg P.V.) dotadas de cânulas ruminais. Os tratamentos foram dispostos em arranjo fatorial 2 x 2 com 40 por cento ou 70 por cento de volumoso (feno de Coast Cross) e zero ou 200 mg de lasalocida/animal/dia. Colheitas de líquido ruminal foram realizadas no 21§ dia de cada subperíodo experimental às 0, 1, 2, 3, 4, 6 e 8 horas após a 1ª refeiçäo. Observou-se interaçäo entre tratamentos sobre a porcentagem molar de propionato e a relaçäo acetato:propionato (p < 0,05): o emprego de menos volumoso aumentou o propionato em 19,0 por cento na presença de lasalocida e 0,6 por cento na sua ausência. Similarmente, a relaçäo A:P diminuiu 20,6 por cento na presença de lasalocida e 4,9 por cento, na sua ausência (p < 0,05). Menor proporçäo de volumoso fez diminuir a porcentagem molar de acetato em 4,7 por cento e aumentar a de butirato em 15,7 por cento, independentemente da lasalocida (p < 0,05). O decréscimo da proporçäo de volumoso aumentou a ingestäo de MS (p < 0,05), diminuiu a concentraçäo ruminal de amônia a partir de 4 horas após a 1ª refeiçäo (p < 0,05), diminuiu o pH do líquido ruminal a partir de 2 horas (p < 0,05) e o fluxo ruminal de líquidos/kg de MS consumida (p < 0,05), mas näo alterou o volume líquido ruminal ou as concentraçöes séricas de uréia

Efeitos da lasalocida sódica e proporçäo volumoso/concentrados sobre a degradabilidade in situ do farelo de soja e do feno coast cross [Cynodon dactylon (L) Pers] em vacas secas / Efects of sodium lasalocid and roughage/concentrate ratio on in situ degradability of soybean meal and coast cross hay [Cynodon dactylon (L) Pers] in dry cows

Foram estudados os efeitos da lasalocida sódica e de diferentes proporçöes volumoso:concentrados sobre a degradabilidade da fibra (FDN e FDA) e PB através de experimento em Quadrado Latino 4 x 4, utilizando-se quatro fêmeas bovinas dotadas de cânulas ruminais, pesando em média 500 kg de peso vivo. Os tratamentos foram dispostos em arranjo fatorial 2 x 2 com 40 por cento ou 70 por cento de volumoso na dieta (39 por cento ou 59 por cento de FDN) e zero ou 200 mg de lasalocida/animal/dia. Utilizaram-se subperíodos de 21 dias, sendo os 16 primeiros destinados à adaptaçäo dos animais à dieta, composta de feno de Coast Cross (Cynodon dactylon) e mistura de concentrados. O ensaio de degradabilidade in situ pela técnica dos sacos de náilon foi realizado do 17§ ao 21§ dia, incubando-se o farelo de soja durante 0, 1,5, 3, 6, 12, 24 e 48 horas e o feno por 0, 6, 12, 24, 48, 72 e 96 horas. Interaçäo foi observada entre lasalocida e a proporçäo volumoso:concentrados da dieta sobre a degradabilidade efetiva da FDN e FDA do feno (p < 0,05). Na ausência de lasalocida, menor proporçäo de volumoso diminuiu a degradabilidade da FDN e FDA em 12,0 por cento e 12,7 por cento, respectivamente, enquanto na sua presença as diminuiçöes foram de 7,0 por cento e 4,9 por cento. Nenhum dos tratamentos alterou significativamente a degradabilidade efetiva da PB do farelo de soja

Desempenho de bezerros desaleitados, recebendo proteína de soja na forma líquida, via goteira esofageana / Weaned valve's performance fed liquid soybean protein through oesophageal groove

Vinte bezerros machos Holandeses, desaleitados, com cerca de 100 dias de idade e 109 kg de peso, foram alimentados com proteína texturizada de soja (PTS) na forma sólida ou líquida.Os animais foram manejados de forma a manter-se a formaçäo de suas goteiras esofageanas, após o desaleitamento, e receberam quatro tratamentos, dentro de um delineamento em blocos ao acaso: A) 100 por cento PTS na forma sólida, mais 4 kg de água; B) 66 por cento PTS na forma sólida, e 33 por cento PTS dissolvida em 4 kg de água; C) 33 por cento PTS na forma sólida, e 66 por cento PTS dissolvida em 4 kg de água; D) 100 por cento PTS dissolvida em 4 kg de água. As porçöes líquidas das dietas foram fornecidas em biberöes e à temperatura de 35 graus centígrados. Desempenhos em ganhos de peso, ingestöes de matéria seca e conversöes alimentares näo mostraram diferenças entre tratamentos

Relações entre as características intervalo desmame-cio, duração do cio e momento da ovulação diagnosticado pela ultra-sonografia em fêmeas da espécie suína / Relationships between the characteristics weaning-to-estrus interval, estrus duration and moment of ovulation by ultrasonography in sows

Estudaram-se as relações entre o intervalo desmame-cio (IDC), a duração do cio (DC) e o momento da ovulação (MO). Foram observadas 236 fêmeas para a obtenção dos dados de IDC e DC, as quais eram testadas para o diagnóstico de cio 4 vezes ao dia, na presença do macho. A ovulação foi diagnosticada em 77 fêmeas, pela ultra-sonografia, por via transcutânea, em 3 exames diários com 8 horas de intervalo. Houve correlação negativa entre intervalo desmame-cio e duração do cio (r=-0,4657; p=0,0001) e entre intervalo desmame-cio e momento da ovulação (r=-0,3955; p=0,0004), no entanto, não houve correlação entre duração do cio e momento da ovulação (r=0,2201; p=0,0578). A porcentagem de fêmeas que ovularam entre 0 e 24, 24 e 48, 48 e 72 e acima de 72 horas após o início do cio foi de, respectivamente, 0 por cento, 58,4 por cento, 37,5 por cento e 4,2 por cento para o IDC de 3 dias, 3,2 por cento, 67,7 por cento, 29,2 por cento e 0 por cento para o IDC de 4 dias, 0 por cento, 91,6 por cento, 8,3 por cento e 0 por cento para o IDC de 5 dias e 10 por cento, 90 por cento, 0 por cento e 0 por cento para o IDC de 6 e 7 dias. Nestas condições, o IDC não se mostrou uma referência confiável para ser utilizado como um preditor do momento ideal da inseminação. No entanto, o conhecimento das características IDC, DC e MO dentro de cada rebanho ajuda a apontar falhas e elaborar programas eficientes de IA.