Fermentation of Soybean Meal with Lactobacillus acidophilus Allows Greater Inclusion of Vegetable Protein in the Diet and Can Reduce Vibrionacea in the Intestine of the South American Catfish (Rhamdia quelen).

The objective of this study was to evaluate the effect of diets containing different inclusion levels (0%, 7%, 14%, 21% and 28%) of soybean meal fermented by Lactobacillus acidophilus (SMFL) on the zootechnical performance and intestinal health of South American catfish juveniles (Rhamdia quelen). The experimental design was completely randomized with five treatments and four replications and lasted 56 days. Five isoproteic (39% crude protein) and isoenergetic (4300 kcal of gross energy kg-1) diets were formulated where SMFL was included in replacement of fish meal. Two hundred forty South American catfish juveniles (3.0 ± 0.5 g) were distributed in 20 tanks (70 L) connected in a recirculation aquaculture system. At the end of the experiment, the inclusion of SMFL up to 21% in replacement of fish meal did not affect the zootechnical performance and also decreased the concentration of Vibrionaceae bacteria present in the intestine compared to the control group. The amount of total lactic and heterotrophic bacteria, the enzymatic activity and the intestinal morphometry did not differ between dietary treatments. The results demonstrate that fermentation with Lactobacillus acidophilus enables greater inclusion of soybean protein in South American catfish diets and promotes the control of intestinal pathogenic bacteria.

Rumination time, activity index, and productive performance of Holstein and crossbred Holstein × jersey cows exposed to different temperature-humidity indexes.

The aim of this study was to evaluate the rumination time, activity index, milk yield (MY), physicochemical milk characteristics, and physiological indicators of pure Holstein (H) and first (F1- ½ Holstein × Jersey) and second-generation (R1- ¾ Holstein × » Jersey) of crossbred cows in a pasture-based system under the influence of different temperature-humidity indexes (THI). Twenty-two multiparous cows (H = 7, F1 = 5, and R1 = 10) were evaluated throughout 1-year period. Daily information on rumination time and activity index was obtained using the software HealthyCow24® and the daily THI was determined from data logger information. Weekly, MY, physicochemical milk characteristics, body weight, body condition score, and physiological indicators were evaluated. THI were grouped into six classes from safe (< 68) to emergency (≥ 84). Variance analyses were performed. There was no interaction between the genetic group and THI classes for any trait. The rumination time was longer for crossbred R1 and F1 cows than for Holstein cows. The activity index increased, and rumination time decreased as the THI classes increased. There was no difference in MY between the genetic groups, but crossbred cows showed higher milk fat and protein content. Our study indicated that the high THI increases the activity index and decreases the rumination time, MY, and the physicochemical quality of milk, BW, BCS, RF, and RT of the three genetic groups (H, F1, and R1).

Evaluation of an electronic system for monitoring dairy cow rumination in a grazing-based system.

This research aimed to compare the rumination time estimated by an electronic monitoring system with direct visual observations of the rumination of dairy cows in a grazing-based system. Also, it aimed to estimate the agreement between different time intervals of the direct visual observations. To that end, we have observed twelve lactating cows for 16 h a day for 11 days. Then, we compared the data provided by the HealthyCow24® software with the visual observations to use as reference. After that, we estimated the Pearson's correlation coefficients, the linear regression, and the Bland-Altman plot by using the SAS software. Results showed that the rumination data estimated by the HealthyCow24® software and the visual observations were highly correlated (0.81; P < 0.0001). In the Bland-Altman analysis, we observed that the average of the standard deviations between the visual observation and the electronic monitoring system was - 2.14 min during a 2-h period. The upper limit (95%) was 30.61 min/2 h and the lower limit (95%) was - 34.88 min/2 h. Moreover, visual observations at intervals of up to 15 min were correlated with the data estimated by the electronic monitoring system and observed at 5-min intervals. In conclusion, the Allflex SCR electronic monitoring system is efficient in measuring the rumination time of grazing cows. Also, direct visual observations with intervals no longer than 15 min are reliable when used for evaluating the behavior of cows without losing data accuracy.

Prevalence of Anaplasma marginale, Babesia bovis, and Babesia bigemina in cattle in the Campos de Lages region, Santa Catarina state, Brazil, estimated by multiplex-PCR.

This study aimed to determine the prevalence of three common hemoparasites (Anaplasma marginale, Babesia bovis and Babesia bigemina) in cattle from 16 counties in the Campos de Lages region, Santa Catarina state, Brazil, and the factors affecting disease occurrence. The study population consisted of 257 clinically healthy animals from 21 rural farms. Bovine blood samples were collected by jugular venipuncture. DNA was extracted from whole blood by the phenol/ chloroform method. Genomic DNA extracted from blood samples was subjected to Multiplex PCR for screening of B. bovis, B. bigemina, and A. marginale using specific primers. Prevalences of A. marginale, B. bigemina, and B. bovis were 27%, 16%, and 29%, respectively. Mixed infection was observed in 17.5% of samples. The most frequent was Babesia bovis and Babesia bigemina in 6.62% of samples. A. marginale infection rates were statistically correlated with age groups of cattle. The infections detected in the study population were considered to be subclinical, based on the presence pathogen DNA and absence of clinical symptoms. Seasonality of the pathogens resulted in various degrees of infection, related to the age of the animals and the season. The Campos de Lages region is characterized by enzootic instability for these pathogens because of its climatic and geographic features.

Multiplicação microbiana no leite cru armazenado em tanques de expansão direta / Microbial multiplication in raw milk stored in direct expansion bulk tanks

O presente estudo objetivou avaliar o efeito do tempo de armazenagem do leite em tanques de expansão direta, modelo de duas e quatro ordenhas, sobre a contagem bacteriana total (CBT) e a contagem de bactérias psicrotróficas (CBP). As avaliações foram conduzidas em 19 propriedades leiteiras, localizadas nas regiões Serrana e Oeste de Santa Catarina, as quais utilizavam equipamentos de refrigeração do leite por expansão direta, modelo de duas ou quatro ordenhas, com taxa de ocupação variando de 60 a 100% de sua capacidade. Antes e após cada ordenha, foram coletadas amostras de leite para análise de CBT, CBP e contagem de células somáticas (CCS), totalizando aproximadamente 36 horas de armazenagem (quatro ordenhas). O tempo de armazenagem do leite cru resfriado não afetou a CBT e CBP (P>0,05) em ambos os modelos. O modelo de tanque de expansão afetou somente a CBP (P<0,05), com média inferior para amostras de leite de tanques de duas ordenhas em relação ao de quatro ordenhas (3,61±0,104 e 4,00±0,120UFC mL-1 (log10), respectivamente). Conclui-se que tanques de resfriamento por expansão direta, utilizados dentro de suas especificações quanto ao volume de leite a ser resfriado, permitem a manutenção da CBT e da CBP em sistemas de transporte do leite ao laticínio a cada 48 horas.

The purpose of this study was to evaluate the effect of the cold storage period of raw milk in bulk tanks, using two and four milking models, on total bacterial count (TBC) and psychrotrophic bacterial count (PBC). A total of 19 dairy farms, located in West and Uplands of the Santa Catarina State - Brazil, was been evaluated. Each dairy farm had direct expansion bulk milk tank and an occupancy rate varying from 60% to 100%. Samples were collected before and after each milking procedure to determine PBC and TBC, totalizing four milking and a storage period of 36 hours. The storage time did not affect TBC and PBC (P>0.05). The bulk tank model only affected the PBC (P < 0.05), with two-milking model presenting a lower mean than four-milking model (3.61±0.104 and 4.00±0.120CFU mL-1 (log10)). It was possible to conclude that bulk tanks, when used properly concerning raw milk volume to be chilled, allow the TBC and PBC to remain stable in the transportation systems of raw milk to the industry each 48 hours.