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Background: Mastitis is an inflammatory disease of the mammary gland, mostly associated with bacterial infections. It is responsible for great economic losses due to decreased milk yield, discarded milk, milk composition alterations and treatment costs, besides it impairs the animal health and welfare. The rumination time is an important behavioral marker and its assessment can be used as an early diagnosis tool, which can improve cure rate. Therefore, the aim of the present study was to evaluate the sensitivity of behavior monitoring system collars in the diagnosis of mastitis and the average rumination time (RT) of Holstein cows during the healthy period and affected by the disease. Materials, Methods & Results: The study was conducted on a commercial property located in the municipality of Rio Grande, Rio Grande do Sul, Brazil. The RT data from 39 multiparous Holstein cows with an average milk yield of 38.4 L/ day was collected. RT monitoring was performed using C-Tech1 collars combined with CowMed® software, which assess behavior data from the animals and emits warning signals when it finds abnormalities in any parameter. In order to verify whether the animals were determined correlated with diseases, the sensitivity of the data was evaluated, when the system had given the alert to animals considered ill, they underwent to a further clinical evaluation performed by a veterinarian to confirm the diagnosis. From the diagnosis, the cows were divided into subclinical mastitis (SM) and clinical mastitis (CM) groups. SM was detected by the California Mastitis Test (CMT) and cows that were graded 1 (++), 2 (++) or 3 (+++) without the presence of any other clinical sign were assigned to the SM group. CM was assessed by observation of abnormalities in milk such as changes in color and consistency, as well as the presence of lumps, clots or blood; and clinical examination of the udder was performed for detection of hot, hard, swollen or painful quarters. Thereafter, variations in the mean RT between the healthy (15 days) and sick periods (days when there was an alert) were evaluated. For the identification of the etiological agents involved in the cases of CM, microbiological cultures were performed on Accumast® plates with milk samples, which were incubated at a temperature of 37°C and the diagnosis of the pathogens were performed after16 hours of incubation. During the study, 57 cases of mastitis were observed, 42 were SM and 15 were CM. The sensitivity of the system, which is the ability to detect positive cases of the disease, was 73.8% for SM and 73.3% for MC. The RT of the animals were compared individually during the healthy period with the sick period and it was observed that SM reduced the RT by 5.33% whereas MC reduced the RT by 14.9%. Discussion: The maximum RT values were lower during the disease period in relation to the period in which the animals were healthy, for both SM and CM, which is due to the fact that the disease is responsible for causing inappetence in animals, among other clinical signs, therefore, reducing feed consumption. The lowest variation in RT, between the healthy and sick period, was observed in cases of SM, which was already expected, since the clinical form tends to cause more discomfort to the animals. As for the main etiological agents involved in the clinical condition, Streptococcus agalactiae and S. uberis were detected. In view of the above, the evaluation of the mean RT of multiparous dairy cows was efficient in the predictive diagnosis of SM and CM up to two days before the onset of the disease. In addition, the variability of this result demonstrated that animals with subclinical cases presented less fluctuation in RT. [ABSTRACT FROM AUTHOR]

The accumulation of industrial by-products increases the use of sweet potato waste for ruminants, but ruminal pH characteristics are still not well known. The objective was to assess the fluctuation of ruminal pH in sheep supplemented with different levels of sweet potato flour inclusion in their diet. Four rumen-fistulated sheep were used; they were fed a diet based on ryegrass haylage (Lolium multiflorum) and sweet potato flour (Ipomoea batatas), provided according to the level of inclusion in the total diet (0, 0.5, 1.0 and 1.5%). Approximately 80 ml of ruminal fluid was collected for reading on a bench pH meter. Statistical data analysis was run on Statistical Analysis System (SAS Institute INC. Cary, NC, USA), and statistical difference was considered for p < 0.05. The animals that received 1.5% of sweet potato flour in their diet presented acid rumen pH; the 1.0% group presented rumen pH acidification in the first 6 hours after feeding, and the 0.5% level of inclusion did not change the rumen environment. It is concluded that the inclusion of 0.5% sweet potato flour in sheep diet proved to be an efficient energy supplementation strategy. [ABSTRACT FROM AUTHOR]

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Background: Reproductive efficiency is one of the most important factors affecting the performance dairy cattle, and fixedtime artificial insemination (TAI) is an important biotechnology factor employed in bovine livestock. The achievement of satisfactory results in TAI protocols depends of several factors, such as health and body condition, milk yield, environmental temperatures, ovulation time, semen manipulation, as well as semen quality. The goal of this study was to evaluate the conception rate of heifers and multiparous cows based on different Holstein bulls used for artificial insemination (AI). The effects of the type of management AI, animal category, and season of the year were also examined. Materials, Methods & Results: A three-year database on the reproductive management of a dairy farm was formed. All the cows and heifers were of the Holstein breed, in semi-intensive nutritional management, milked twice a day, and received a total mix ration. After 45 days in milk, when cows were observed twice daily with estrus signs, posterior artificial insemination occurred 12 h after estrus visualization was made. However, cows that were not observed in estrus were submitted to a timed artificial insemination (TAI). In this study, these fixed factors were considered: bulls utilized for the AI (totalizing 10 animals with at least 100 inseminations in each season, denoted by the letter B and a number - B1, B2, B3, B4, B5, B6, B7, B8, B9, B10); the season of the insemination (spring/summer being from November to April and autumn/winter from May to October), category animal (heifers, animals that never have been calved, or multiparous, animals that have already given birth more than once), and the type of AI (which included TAI using a protocol for synchronization, but cows having not necessarily shown estrus signs at the AI; ETAI: using protocol of synchronization, cows showing estrus signs at the AI; and AI with estrus visualization, without protocol of synchronization when animals were observed in estrus and were inseminated 12 h later. The fertility parameter of the bulls and reproductive performance in AI was based on conception rate. There was a statistical difference among different bulls in the same season (P = 0.05). There was also a difference in reproductive performance of the same bulls between seasons, autumn/winter and spring/summer; B8 37.8% vs. 32.0% (P = 0.05) and B10 35.1% vs. 20.7% (P = 0.003). Regarding the individual animal category, only one bull (B6) demonstrated higher reproductive performance when utilized in the AI of heifers than multiparous 39.2% vs. 27.2% (P = 0.01). Similarly, regarding the effect of the type of AI, only one bull (B8) exhibited different results, obtaining better results for conception rate when utilized in fixed TAI with estrus visualization (35.5%) and in the AI with estrus visualization (39.0%) compared with that of TAI [19.9%] (P < 0.05). Discussion: From these results, it was observed that some bulls exhibited better performance in situations of greater challenge. In addition, some animals presented variation in efficiency with the demonstration of estrus or not. Therefore, bulls that present semen with higher fertility in certain types of AI could be utilized on a larger scale for to increase the reproductive rates in artificial insemination. The results of this study indicate that despite the tests indicating the semen that is submitted is adequate, there are still variations in quality and the reproductive efficiency of each bull. With the effects varying based on fertility and on different environmental and management situations. [ABSTRACT FROM AUTHOR]

Background: The timed artificial insemination (TAI) protocols have been used worldwide as a first service artificial insemination (AI) breed system as well as to resynchronize cows diagnosed as not pregnant. The benefits associated to Heatsynch are the lower cost of the protocol and the increase in the number of cows detected in estrus. Furthermore, it has been suggested that protocols combining AI after estrus detection followed by TAI could increase overall conception rates, as well as increased AI submission rates. The aim of this study was evaluate reproductive responses of dairy cows submitted to a Heatsynch protocol according the estrus behavior and controlled internal device release (CIDR) uses. Material, Methods & Results: Holstein lactating cows (n = 562) were enrolled in protocol using (CIDR) (1.9 g of progesterone) insertion at (day 0) D0 either a new one, a previous used once (7 days - second use) or twice used (14 days - third use). Based on the detection of estrus and the moment of AI after the CIDR removal, cows were divided into 3 groups: cows showing signs of estrus and therefore AI 36 to 60 h after CIDR removal (EPTAI group; n = 241); cows showing estrus and AI 72 h after CIDR removal (ETAI group; n = 207); and cows that did not show any sign of estrus after CIDR removal and were TAI 72 h later (NoETAI group; n = 335). Previous to the first postpartum insemination (47.01 ± 5.43 days in milk) cows were pre-synchronized using one dose of PGF2α (Lutalyse, Pfizer Saúde Animal, Brazil). At 60 ± 3.52 days in milk (DIM), day 0 of the Heatsynch protocol, cows were subjected to gynecological examination by a Veterinarian, where only those animals considered as healthy cows with no signs of uterine disease were kept in the study. In a subset of animals (105/783; 13.4%) an ovary evaluation was performed by ultrasonography (WED-3000, B-mode, linear array, ultrasound scanner equipped with a 5.0-MHz transducer, Welld, Shenzhen, China) at the beginning of synchronization protocol aiming to check the presence of a corpus luteum (CL) and classify the cows as cycling or not cycling. Ovarian structures were examinated aiming to check the CL presence on day zero of the program in a subset of the cows and pregnancy status was also determined by ultrasonography. Higher conception rates were found in EPTAI and ETAI groups than NoETAI, respectivaly 44.8%, 38.2% and 24.8%. Pregnancy losses were calculating considering cows that were not pregnant at 60-65 days re-check and those that showed signs of estrus before the first pregnancy determination. The CIDR reutilization did not affect the estrus behavior, conception rate or pregnancy losses. In conclusion, reproductive responses in dairy cows during a Heatsynch protocol are not affected by CIDR reutilization and are improved in cows showing estrus signs. Discussion: Cows submitted to Heatsynch protocols that demonstrate estrus signs have increased pregnancy rates and lower pregnancy losses. In addition to that, cows exposed to low estradiol concentrations were more likely to experience subsequent premature luteolysis. Thus, coupled with the estradiol cypionate (ECP) action, it can be postulated that cows showing estrus signs during a timed AI protocol could have a higher ovulation rate. This can assume great importance in high producing dairy herds, since in response to ECP becomes possible to overcome the lower concentrations of estradiol due to high hepatic clearance and catabolism o esteroid hormones. [ABSTRACT FROM AUTHOR]

The aim of this study was to confirm the possible consequences of prepartum lameness on subsequent lactation among Holstein cows. In this research, 27 multiparous cows, were monitored from the 30th to 63rd day, relative to calving. Thirty days prior to parturition, the animals were segregated into two groups based on the locomotion score (LS), where LS 1 is attributed to animals without claudication, LS 2 to those with suspected lameness and LS 3, 4 and 5 to those with mild, moderate and severe lameness, respectively; in the lame cows group (LC) (n=15), the animals displayed LS ≥ 3, whereas in the non-lame cows group (NLC) (n=12) they showed LS 1. Milk production, body condition score (BCS) and blood concentration levels of β-hydroxybutyrate (BHB), urea, phosphorus, calcium aspartate aminotransferase (AST), gamma glutamyl transferase (GGT) and total plasma proteins (PPT) were evaluated. Milk production (17.675 ± 0.31 L of milk/day) and blood calcium concentration (7.42 ± 0.12 mg/dL) were lower in the lame cows in comparison to those without lameness (22.27 ± 0.42 L of milk/day and 9.63 ± 0.13 mg/dL). Besides, the lame cows showed higher BCS loss during the early postpartum period. The metabolites AST, GGT, PPT, urea, BHB and phosphorus revealed no difference between the groups during the period evaluated. The lameness evident in cows during prepartum exerted major negative effects on the milk production and calcemia, making the LS evaluation during these period an important tool in the early diagnosis of losses for future lactation. [ABSTRACT FROM AUTHOR]