Comparison between intrauterine application of an antibiotic and an herbal product to treat clinical endometritis in dairy cattle - A randomized multicentre field study.

Uterine diseases are main indications for antibiotic use in dairy cows. To test a non-antibiotic treatment option, we compared the effect of an intrauterine cephapirin (Metricure®; cefapirin benzathin 500 mg per dosis; CEPH) with an intrauterine applied herbal product (25 ml of EucaComp® PlantaVet containing alcoholic extracts of Calendula officinalis L., Mellissa officinalis L., Origanum majorana L. and Eucalyptus globulus Labill. (EUC)) on the clinical cure of endometritis. Examinations of 816 cows between 21 and 35 days after calving were performed and cases of clinical endometritis (n = 169) were included. Diagnosis based on a scoring system for vaginal discharge. Study animals were randomly assigned to one of two treatment groups and treated immediately. After excluding animals with incomplete datasets, 136 cows (EUC: n = 61; CEPH: n = 75) remained for the final analysis. In total, 64% (EUC: 61%, CEPH: 67%) of analysed endometritis cases were considered as clinically cured 14 ± 2 days after the first treatment, 15% stayed uncured after the application of a maximum of two consecutive treatments, leading to an overall clinical cure rate of 85% (EUC: 82%, CEPH: 88%). No statistically difference in clinical cure rates could be observed between both treatment groups nor 14 ± 2 days after the first treatment (p = 0.956) neither regarding the overall cure rate (p = 0.923). In conclusion, the clinical cure of dairy cows' endometritis after the intrauterine application of the herbal product was non-inferior to the intrauterine application of the antibiotic cephapirin. These results could contribute to reduce the antimicrobial use in the daily veterinary routine treatment of endometritis.

Supplementation of rumen-protected lysine during the close-up period improves vaginal discharge clearance in Holstein dairy cows.

We aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on uterine involution and the resumption of ovarian function in dairy cows. Fifty-two multiparous Holstein cows were categorized based on parity and expected calving date and randomly assigned to the RPL or control (CON) groups. The RPL group received 80 g of RPL daily from day 21 before the expected calving date until parturition. Blood samples were obtained twice weekly from pre-supplementation to 6 weeks postpartum. The onset of luteal activity postpartum was determined via ultrasonography twice weekly for up to 6 weeks postpartum. Uterine involution was tracked at 3 and 5 weeks postpartum through the vaginal discharge score, percentage of polymorphonuclear cells (PMN) in endometrial cytology samples, presence of intrauterine fluid, and gravid horn diameter via ultrasonography. Before supplementation, the RPL group showed amino acid imbalance, which was improved by RPL supplementation. There were no significant differences in the onset of luteal activity, percentage of PMN, intrauterine fluid, or the diameter of the uterine horn between the two groups. The vaginal discharge score in the RPL group decreased from 3 to 5 weeks postpartum, whereas that in the CON groups did not decrease. The number of cows with clinical endometritis was lower in the RPL group. Overall, RPL supplementation during the close-up period enhanced vaginal discharge clearance, potentially averting clinical endometritis, but did not affect the first ovulation in dairy cows.

Utilisation of indigenous knowledge to control gastrointestinal nematodes in Southern Africa.

Gastrointestinal nematodes (GIN) exacerbate the impact of droughts on the survival of cattle. The inadequacies of the conventional system make it increasingly important to explore indigenous knowledge (IK) to create drought-tolerant and GIN resilient herds. The objective of the study was to assess the indigenous strategies for controlling GIN during droughts. Face-to-face interviews with experts on IK were conducted to give insight into the importance, methods and ranking of GIN control. The experts identified 86 cattle that were used to test their assertions. The control methods used were identifying cattle that were susceptible to high GIN loads using predisposing factors, diagnosis of GIN burdens using faecal appearance, and treatment using phytotherapy. Experts ranked predisposing factors as the most critical control strategy and identified body condition, class, sex, coat colour, pregnancy status and lactation status as predisposing factors to high GIN burdens. Thin, older, dark-coloured cattle, as well as pregnant and lactating cows, were considered susceptible to GIN. However, pregnancy status, coat colour and sex were significantly associated with high GIN burdens. Cows were 2.6 times more likely to have high GIN burdens than bulls. Dark-coloured cattle were 3.5 times more likely to have high GIN burdens than light-coloured ones, and the likelihood of pregnant cows was 4.9 times higher than non-pregnant cows. A dark-coloured pregnant cow was extremely susceptible to high GIN burdens. In conclusion, knowledge of predisposing factors informs selection decisions when purchasing foundation stock. Cattle that are susceptible to high GIN loads are prioritised during droughts or culled where resources are scarce.

Factors affecting N-acetyl-ß-D-glucosaminidase as an indicator for mastitis detection in dairy sheep.

The study of new indirect methods for mastitis detection is of great relevance both at the economic level of the farm and dairies, and in terms of consumer health, and animal welfare. These methods help us to monitor the disease and speed up the decision-making process on treatment of the affected animal and the destination of the milk. The main aim of this work was to study the effect of intramammary infection and other non-infectious factors on the activity of the enzyme N-acetyl-ß-D-glucosaminidase (NAGase) in milk, in order to evaluate its use as an indicator for the early diagnosis of mastitis in sheep that could be less expensive, easier to measure and a better marker of inflammation or complementary to existing methods such as somatic cell count (SCC). Seven biweekly samplings were carried out, in which NAGase activity, SCC and milk were analyzed. Glands were classified according to their sanitary status based on the results of the SCC and bacteriological analysis. Non-infectious factors such as lactation stage, parity number and milking session had a statistically significant effect on NAGase values, finding the highest NAGase values at the onset and end of the study, in infectious mastitic glands of multiparous females and at morning milking. However, among the NAGase variation factors studied, the health status of the gland was the factor that caused the highest variation in enzyme levels, with infectious mastitic glands showing higher values than healthy glands. The predictive ability of NAGase was also studied by means of several logistic regression models, with the one that included NAGase together with lactation stage and parity obtaining the best results if sensitivity is to be prioritized, or the model that included NAGase, lactation stage, parity, milking and production if specificity is to be prioritized. From the results obtained, it can be concluded that the use of NAGase as an intramammary infection detection method in sheep can be useful when non-infectious factors that cause changes in the concentration of the enzyme are also considered.

Construction of luciferase-expressing Neospora caninum and drug screening.

BACKGROUND: Neospora caninum is an apicomplexan parasite that is particularly responsible for abortions in cattle and neuromuscular disease in dogs. Due to the limited effectiveness of currently available drugs, there is an urgent need for new therapeutic approaches to control neosporosis. Luciferase-based assays are potentially powerful tools in the search for antiprotozoal compounds, permitting the development of faster and more automated assays. The aim of this study was to construct a luciferase-expressing N. caninum and evaluate anti-N. caninum drugs. METHODS: Luciferase-expressing N. caninum (Nc1-Luc) was constructed using clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9). After testing the luciferase expression and phenotype of the Nc1-Luc strains, the drug sensitivity of Nc1-Luc strains was determined by treating them with known positive or negative drugs and calculating the half-maximal inhibitory concentration (IC50). The selective pan-rapidly accelerated fibrosarcoma (pan-RAF) inhibitor TAK-632 was then evaluated for anti-N. caninum effects using Nc1-Luc by luciferase activity reduction assay and other in vitro and in vivo studies. RESULTS: The phenotypes and drug sensitivity of Nc1-Luc strains were consistent with those of the parental strains Nc1, and Nc1-Luc strains can be used to determine the IC50 for anti-N. caninum drugs. Using the Nc1-Luc strains, TAK-632 showed promising activity against N. caninum, with an IC50 of 0.6131 µM and a selectivity index (SI) of 62.53. In vitro studies demonstrated that TAK-632 inhibited the invasion, proliferation, and division of N. caninum tachyzoites. In vivo studies showed that TAK-632 attenuated the virulence of N. caninum in mice and significantly reduced the parasite burden in the brain. CONCLUSIONS: In conclusion, a luciferase-expressing N. caninum strain was successfully constructed, which provides an effective tool for drug screening and related research on N. caninum. In addition, TAK-632 was found to inhibit the growth of N. caninum, which could be considered as a candidate lead compound for new therapeutics for neosporosis.

Immunophenotyping of peripheral circulating lymphocytes and serum selenium levels in calves with neonatal diarrhea.

This work aims to: (1) elucidate the immune response exhibited by CD4 + and CD8 + T lymphocyte cells in response to various infectious agents in calves suffering with neonatal diarrhea; and (2) determine and investigate the association between serum selenium levels and T lymphocyte subtypes in neonatal calves afflicted with neonatal diarrhea and infected with various infectious agents. The study encompassed a cohort of 50 calves, encompassing both sexes and various breeds, within the neonatal age range (1-28 days old). Subdivided into distinct groups, the calves were categorized based on the causative agents of neonatal diarrhea, including Rotavirus (n = 10), Cryptosporidium parvum (C.parvum) (n = 10), Coronavirus (n = 5), Rotavirus+C.parvum (n = 5), and a Control group (n = 20). Blood samples were meticulously obtained from the vena jugularis of all animals utilizing specific techniques-8 ml in tubes devoid of anticoagulant and 3 ml in blood collection tubes containing EDTA. Serum selenium levels were analyzed by ICP-MS. Flow Cytometry device was used to determine CD4 + and CD8 +T lymphocyte levels. In this study, although there was no statistically significant difference in serum selenium levels between all study groups, it was found that the selenium level in the control group was not sufficient. CD4 T lymphocyte levels, the rotavirus+C.parvum group exhibited a statistically significant elevation compared to the coronavirus group. Regarding CD8 + T lymphocyte levels, the coronavirus group demonstrated a statistically significant increase when compared to the control group. In intragroup analyses of CD8 + T lymphocyte levels, the coronavirus group exhibited a significant elevation compared to the rotavirus group, C.parvum group, and the C.parvum + Rotavirus group. A significant negative correlation was detected between selenium levels and CD4 + T lymphocytes, while no correlation was found between CD8 + T lymphocytes. Fibrinogen concentration exhibited statistical significance, being higher in the Rotavirus group (p < 0.008) compared to the control group, in the C.parvum group (p < 0.004) compared to the control group, and in the Coronavirus group (p < 0.001) compared to the control group. The leukocyte count demonstrated statistical significance, being higher in the Rotavirus group compared to the control group (p < 0.001), in the Rotavirus+C.parvum group compared to the control group (p < 0.002), and in the Coronavirus group compared to the control group (p < 0.011). In conclusion, the data derived from this study illuminate discernible disparities in CD4 + and CD8 + T lymphocyte immune responses, contingent upon the specific etiological agent associated with neonatal diarrhea. Furthermore, the study underscores the importance of considering selenium deficiency as a relevant factor in calves affected by neonatal diarrhea.

Immunomodulatory effect of Lacticaseibacillus casei CB054 supplementation in calves vaccinated against infectious bovine rhinotracheitis.

Probiotics are live microorganisms that, confer health benefits to the host when supplemented in adequate amounts. They can promote immunomodulation by inducing phagocyte activity, leukocyte proliferation, antibody production, and cytokine expression. Lactic acid bacteria (BAL) are important probiotic specimens with properties that can improves ruminant nutrition, productivity and immunity. The aim of the present study was to evaluate the immunomodulatory effect of the supplementation with Lacticaseibacillus casei CB054 in calve vaccinated against bovine infectious rhinotracheitis (IBR). Calve were vaccinated with a commercial IBR vaccine, on day 0 and received a booster dose on day 21. L. casei CB054 was orally administered (4 ×109 UFC) for 35 days, while a non-supplemented control group received Phosphate Buffer Saline (PBS). Stimulation of bovine splenocytes with L. casei CB054 markedly enhanced mRNA transcription levels of cytokines IL2, IL4, IL10 and IL17 genes. Calves supplemented with L. casei CB054 showed significantly higher (p < 0.05) specific anti-BoHV-1 IgG levels, higher serum neutralization, as well as higher mRNA transcription for IL2, IL4, IL10 and IL17 genes in Peripheral Blood Mononuclear Cells (PBMCs) comparing with control calves. Supplemented calve had an average weight gain of ∼14 kg more than non-supplemented during the experimental period. These results suggest that L. casei CB054 supplementation increase immunogenicity of a commercial IBR vaccine in cattle and improve weight gain.

Alternatives to conventional antibiotics for the prevention and treatment of commonly occurring diseases in feedlot cattle.

Antibiotic-resistant bacteria are a problem in human medicine. The development of antibiotic resistance in bacteria in feedlot cattle could have negative effects on their health and welfare and there is a theoretical possibility of transmission of antibiotic-resistant bacteria from food animals to humans. Alternatives to conventional antibiotics in feedlot health management could reduce the selective pressure for the development of antibiotic resistance. This review assesses the evidence supporting potential alternatives to conventional antibiotics in the prevention and treatment of diseases in feedlot cattle, including nitric oxide, plant extracts, supplemental yeast or yeast products, bacterial probiotics, organic acids, bacteriophages and non-specific immunostimulants. Further research is warranted with lactate utilising bacteria, the organic acid malate, bacteriophages and the non-specific immunostimulants ß-1,3 glucan and those based on pox viruses. However, none of the alternatives to conventional antibiotics investigated in this review have sufficient supporting evidence to date to justify their use with feedlot cattle. Frequently, statistically weak results and studies without negative controls are cited as support for similar studies. The health and welfare of feedlot cattle are dependent on the use of products that have robust supporting data to ensure efficacy and to avoid adverse outcomes.

Estimation of epidemiological cut-off values for eight antibiotics used for treatment of bovine mastitis caused by Streptococcus uberis and Streptococcus dysgalactiae subsp. dysgalactiae.

Interpretive criteria for antimicrobial susceptibility testing are lacking for most antimicrobials used for bovine streptococcal mastitis. The objectives of this study were to determine (tentative) epidemiological cut-off ((T)ECOFF) values for clinically relevant antibiotics used for treatment of bovine mastitis, and to estimate the proportion of acquired resistance (non-wild-types) in Streptococcus dysgalactiae subsp. dysgalactiae and Streptococcus uberis. A total of 255 S. uberis and 231 S. dysgalactiae subsp. dysgalactiae isolates were obtained in Denmark and Norway from bovine mastitis. The isolates were tested for susceptibility to 10 antibiotics using broth microdilution. In accordance with the European Committee on Antimicrobial Susceptibility Testing (EUCAST) standard operating procedure, additional published MIC distributions were included for the estimation of ECOFFs for cloxacillin, cephapirin, lincomycin and tylosin, and TECOFFs for amoxicillin, benzylpenicillin, cephapirin and oxytetracycline. The proportion of non-wild-type (NWT) isolates for the beta-lactams was significantly higher in the Danish S. uberis (45-55%) compared to the Norwegian isolates (10-13%). For oxytetracycline, the proportion of NWT was significantly higher in the Danish isolates, both for S. uberis (28% vs. 3%) and S. dysgalactiae (22% vs. 0%). A bridging study testing in parallel MICs in a subset of isolates (n = 83) with the CLSI-specified and the EUCAST-specified broths showed excellent correlation between the MICs obtained with the two methods. The new ECOFFs and TECOFFs proposed in this study can be used for surveillance of antimicrobial resistance, and - for antimicrobials licensed for streptococcal bovine mastitis - as surrogate clinical breakpoints for predicting their clinical efficacy for this indication.

The effect and mechanism of selenium supplementation on the proliferation capacity of bovine endometrial epithelial cells exposed to lipopolysaccharide in vitro under high cortisol background.

Bovine endometritis severely inhibits uterine repair and causes considerable economic loss. Besides, parturition-induced high cortisol levels inhibit immune function, reduce cell proliferation, and further inhibit tissue repair. Selenium (Se) is an essential trace element for animals to maintain normal physiological function and has powerful antioxidant functions. This study investigated whether Se supplementation reduces endometrial damage and promotes tissue repair in cows with endometritis under stress and explored the underlying mechanism. Primary bovine endometrial epithelial cells were isolated and purified from healthy cows. The cells were treated with different combinations of lipopolysaccharide (LPS), cortisol, and various concentrations of Se. Data showed that LPS stimulation inhibited cell proliferation and increased cell apoptosis. High levels of cortisol further exacerbated these effects. Flow cytometry, scratch wound healing tests, and 5-ethynyl-2'-deoxyuridine (EdU) proliferation assays showed that Se supplementation promoted cell cycle progression, cell migration, and cell proliferation in the presence of LPS and cortisol. The quantitative PCR results showed that the expression of related growth factors was increased after Se supplementation. After administering various inhibitors, we further demonstrated that Se supplementation decreased the activity of glycogen synthetase kinase 3ß (GSK-3ß) through the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway to reduce the degradation of ß-catenin except the Wnt signal to promote cell proliferation. In conclusion, Se supplementation attenuated the cell damage induced by LPS at high cortisol levels and increased cell proliferation to promote uterine repair by elevating the mRNA expression of TGFB3 and VEGFA and activating the PI3K/AKT/GSK-3ß/ß-catenin signaling pathway.

After parturition, endometritis is a common bovine disease, which hinders endometrial repair and reduces bovine economic value. Besides, parturition-induced high cortisol levels cause immunosuppression, aggravate infection, and further inhibit cell proliferation and tissue repair. As an essential trace element, adding selenium to feed helps to maintain the normal physiological function of animals. This study developed a cellular model using lipopolysaccharide (LPS) and cortisol to simulate cows with endometritis in stress conditions. The results showed that Se supplementation attenuated bovine endometrial epithelial cell damage and promoted their proliferation in the presence of LPS and high cortisol levels, which are positively correlated with the concentration of Se. Besides, this study proved another molecular mechanism for Se to regulate ß-catenin except for the Wnt signal by affecting the ß-catenin degradation pathway.

Effects of dietary rumen-protected choline supplementation to periparturient dairy cattle on inflammation and metabolism in mammary and liver tissue during an intramammary lipopolysaccharide challenge.

The objective of this experiment was to examine the effects of supplementation and dose of rumen-protected choline (RPC) on markers of inflammation and metabolism in liver and mammary tissue during an intramammary lipopolysaccharide (LPS) challenge. Parous Holstein cows were blocked by calving month and randomly assigned within block to receive 45 g/d of RPC (20.4 g/d of choline ions; CHOL45), 30 g/d of RPC (13.6 g/d of choline ions; CHOL30), or no RPC (CON) as a top-dress starting 24 d before expected calving until 21 d postpartum. Cows were alternately assigned within treatment group to either receive an intramammary LPS challenge (200 µg in each rear quarter; Escherichia coli O111:B4) or not at 17 DIM (CHOL45, n = 9; CHOL45-LPS, n = 9; CHOL30, n = 11; CHOL30-LPS, n = 10; CON, n = 10; CON-LPS, n = 9). Hepatic and mammary tissues were collected from all cows on d 17 postpartum. Hepatic and mammary tissues were collected at ∼7.5 and 8 h, respectively, after the LPS challenge. An additional mammary biopsy was conducted on LPS-challenged cows (CHOL45-LPS, CHOL30-LPS, and CON-LPS) at 48 h postchallenge. Hepatic and mammary RNA copy numbers were quantified for genes involved in apoptosis, methylation, inflammation, oxidative stress, and mitochondrial function using NanoString technology. Targeted metabolomics was conducted only on mammary tissue samples (both 8 and 48 h biopsies) to quantify 143 metabolites including choline metabolites, amino acids, biogenic amines and derivatives, organic acids, carnitines, and glucose. Hepatic IFNG was greater in CHOL45 as compared with CON in unchallenged cows, suggesting an improvement in type 1 immune responses. Hepatic CASP3 was greater in CHOL45-LPS as compared with CON-LPS, suggesting greater apoptosis. Mammary IL6 was reduced in CHOL30-LPS cows as compared with CHOL45-LPS and CON-LPS (8 and 48 h). Mammary GPX4 and COX5A were reduced in CHOL30-LPS as compared with CON-LPS (8 h), and SDHA was reduced in CHOL30-LPS as compared with CON-LPS (8 and 48 h). Both CHOL30-LPS and CHOL45-LPS cows had lesser mammary ATP5J than CON-LPS, suggesting that dietary RPC supplementation altered mitochondrial function following LPS challenge. Treatment did not affect mammary concentrations of any metabolite in unchallenged cows, and only 4 metabolites were affected by dietary RPC supplementation in LPS-challenged cows. Mammary concentrations of isobutyric acid and 2 acyl-carnitines (C4:1 and C10:2) were reduced in CHOL45-LPS as compared with CHOL30-LPS and CON-LPS. Taken together, reductions in medium- and short-chain carnitines along with an increase in long-chain carnitines in mammary tissue from CHOL45-LPS cows suggests less fatty acid entry into the ß oxidation pathway. Although the intramammary LPS challenge profoundly affected markers for inflammation and metabolism in liver and mammary tissue, dietary RPC supplementation had minimal effects on inflammatory markers and the mammary metabolome.

Pollen beetle (Astylus atromaculatus)-associated gastroenteric disease in cattle: report of 6 natural outbreaks.

Astylus atromaculatus is a pollen beetle native to South America, commonly found in crop flowers. Experimental intoxication of sheep and guinea pigs by this beetle resulting in fibrinonecrotizing enteritis has been reported. We describe here 6 natural outbreaks of intoxication in cattle associated with consumption of alfalfa (5 of 6) and mixed native (1 of 6) pastures heavily contaminated with A. atromaculatus. The outbreaks occurred during the summer (January-February) of 2023 in Argentina (n = 4) and Uruguay (n = 2), in beef cattle under extensive or semi-extensive rearing systems, with overall cumulative incidence and mortality of 22.3% and 17.8%, respectively. The main clinical signs included acute onset of anorexia, lethargy, hyperthermia, hindlimb weakness, reluctance to move, and diarrhea, for up to 15 d. In 2 outbreaks, sudden death was observed. Eight Hereford, Angus, and/or crossbreed heifers, cows, steers, and/or calves were autopsied. Gross and microscopic findings included multifocal necrosis with fibrinous pseudomembranes in the forestomachs and/or small and large intestines. Fragments or whole specimens of A. atromaculatus were identified in the ruminal content of all animals. Testing for multiple gastroenteric pathogens was negative as was testing of A. atromaculatus for cantharidin and batrachotoxin. GC-MS and LC-MS/MS performed on the beetles did not identify any known toxic compounds. Based on the exposure to A. atromaculatus-contaminated pasture, gross and microscopic lesions, and negative results of all testing for multiple gastroenteric pathogens, a diagnosis of intoxication by A. atromaculatus is proposed. Disease caused by A. atromaculatus consumption has not been reported previously in cattle, to our knowledge.

Effect of rumen-protected choline on dairy cow metabolism, immunity, lactation performance, and vaginal discharge microbiome.

Rumen-protected choline (RPC) promotes benefits in milk production, immunity, and health in dairy cows by optimizing lipid metabolism during transition period management and early lactation. However, the RPC success in dairy cows depends on choline bioavailability, which is affected by the type of protection used in rumen-protected choline. Therefore, our objectives were to determine the effects of a novel RPC on dry matter intake (DMI), identify markers of metabolism and immunity, and evaluate lactation performance. Dry Holstein (n = 48) cows at 245 ± 3 d of gestation were blocked by parity and assigned to control or RPC treatment within each block. Cows enrolled in the RPC treatment received 15 g/d of CholiGEM (Kemin Industries, Cavriago RE, Italy) from 21 d prepartum and 30 g/d of CholiGEM from calving to 21 d postpartum. During the transition period, DMI was measured daily, and blood was sampled weekly for energy-related metabolites such as ß-hydroxybutyrate (BHB), glucose, and nonesterified fatty acids (NEFA), as well as immune function markers such as haptoglobin (Hp) and lipopolysaccharide-binding protein (LPB). Vaginal discharge samples were collected at the calving and 7 d postpartum and stored in microcentrifuge tubes at -80°C until 16S rRNA sequencing. The main responses of body condition score, body weight, DMI, milk yield, milk components, and immune function markers were analyzed using the GLIMMIX procedure of SAS with the effects of treatment, time, parity, and relevant covariates added to the models. The relative abundance of microbiome α-diversity was evaluated by 3 indexes (Chao1, Shannon, and Simpson) and ß-diversity by principal coordinate analysis and permutational multivariate ANOVA. We found no differences in DMI in the pre- and postpartum periods. Cows fed RPC increased the yields of energy- and 3.5% fat-corrected milk and fat yield in primiparous and multiparous cows, with an interaction between treatment and parity for these lactation variables. However, we found no differences in milk protein and lactose up to 150 DIM between treatments. Glucose, NEFA, and BHB had no differences between the treatments. However, RPC decreased BHB numerically (control = 1.07 ± 0.13 vs. RPC = 0.63 ± 0.13) in multiparous on the third week postpartum and tended to reduce the incidence of subclinical ketosis (12.7% vs. 4.2%). No effects for Hp and LPB were found in cows fed RPC. Chao1, Shannon, and Simpson indexes were lower at calving in the RPC treatment than in the Control. However, no differences were found 7 d later for Chao1, Shannon, and Simpson indexes. The vaginal discharge microbiome was altered in cows fed RPC at 7 d postpartum. Fusobacterium, a common pathogen associated with metritis, was reduced in cows fed RPC. Rumen-protected choline enhanced lactation performance and health and altered the vaginal discharge microbiome which is a potential proxy for uterine healthy in dairy cows. The current study's findings corroborate that RPC is a tool to support adaptation to lactation and shed light on opportunities for further research in reproductive health.

[The lipidosis in the liver of the dairy cow: Part 2 Genetic predisposition and prophylaxis]. / Die Leberverfettung der Milchkuh: Teil 2.

Hepatic lipidosis in dairy cows is the result of a disturbed balance between the uptake of non-esterified fatty acids (NEFA), their metabolism in the hepatocytes, and the limited efflux of TG as very-low-density lipoprotein (VLDL). Lipidosis and the associated risk for ketosis represents a consequence of selecting dairy cows primarily for milk production without considering the basic physiological mechanisms of this trait. The overall risk for lipidosis and ketosis possesses a genetic background and the recently released new breeding value of the German Holstein Friesian cows now sets the path for correction of this risk and in that confirms the assumed genetic threat. Ectopic fat deposition in the liver is the result of various steps including lipolysis, uptake of fat by the liver cell, its metabolism, and finally release as very-low-density lipoprotein (VLDL). These reactions may be modulated directly or indirectly and hence, serve as basis for prophylactic measures. The pertaining methods are described in order to support an improved understanding of the pathogenesis of lipidosis and ketosis. They consist of feeding a glucogenic diet, restricted feeding during the close-up time as well as supplementation with choline, niacin, carnitine, or the reduction of milking frequency. Prophylactic measures for the prevention of ketosis are also included in this discussion.

Evaluation of synergism in essential oils against the cattle tick Rhipicephalus microplus in Burkina Faso.

The cattle tick Rhipicephalus microplus affects animal production economically by reducing weight gain and milk production and causing diseases, such as babesiosis and anaplasmosis. Using synthetic acaricides to reduce their incidence has caused the emergence of resistant tick populations. The present study aimed to assess the in vitro acaricidal activity of combinations of essential oils (EOs) from Ocimum americanum, Ocimum gratissimum, and Lippia multiflora against R. microplus larvae. In fact, numerous biological properties have been reported on EOs from these three plants, including acaricidal properties. Hence, a larval immersion test was performed using a population of R. microplus resistant to synthetic acaricides used in Burkina Faso. Results revealed that EO from O. gratissimum was the most effective on R. microplus larvae with LC50 and LC90 values at 10.36 and 15.51 mg/mL, respectively. For EO combinations, the most significant synergistic effect was obtained by combination 6 (1/3 O. americanum + 2/3 O. gratissimum +1/6 L. multiflora), with a combination index value of 0.44. All combinations presented dose reduction index >1, indicating a favorable dose reduction. According to the literature, this is the first study to determine the combination effect of EOs from the abovementioned plants in controlling R. microplus activity in vitro. Thus, the combination of these EOs is an alternative to control the resistant populations of invasive cattle ticks.

Efficacy of oral administration of specific immunoglobulins in preventing neonatal calf diarrhoea in dairy herds.

BACKGROUND: The aim of this study was to evaluate the efficacy of bovine concentrated lactoserum (BCL) containing specific immunoglobulin G against Escherichia coli, rotavirus and coronavirus in preventing neonatal calf diarrhoea (NCD). METHODS: A total of 489 newborn calves from 35 herds were orally given either BCL or a placebo before the first feeding of colostrum and clinically supervised by the farmers for the first 14 days of life. The diarrhoea score was defined according to the following criteria: 0 = no diarrhoea; 1 = light diarrhoea without medical treatment; 2 = diarrhoea requiring oral treatment (rehydration and/or antibiotic therapy); and 3 = severe diarrhoea requiring parenteral rehydration or resulting in death. RESULTS: A total of 138 calves suffered from diarrhoea (28%), and 65 (13%) showed signs of diarrhoea requiring treatment. The odds of getting NCD were reduced (odds ratio = 0.326; p < 0.001) in the BCL group. There was a tendency towards a reduction in the duration of NCD in the BCL group (2.25 (±1.7) days vs. 2.88 (±2.7) days in the placebo group) (p = 0.052). Furthermore, no calves died in the BCL group, whereas four calves died in the placebo group. LIMITATIONS: Because of the design of the study using animals in practice, the mechanisms explaining the clinical findings remain as hypotheses. Diarrhoea scoring performed by farmers has to be analysed and interpreted with caution. CONCLUSIONS: This study demonstrates that BCL as a single preventive treatment is effective in reducing the incidence of NCD even in a region with good general management of dairy calves and overall good colostrum quality.

Utilizing intramammary Melaleuca alternifolia as an organic internal sealant for dry-off therapy in Murrah buffaloes.

The effects of intramammary dry cow therapy based on the administration of 5% Melaleuca alternifolia tea tree essential oil (TTO) as an internal teat sealant to Murrah cows were evaluated. A longitudinal prospective and retrospective negative control study was performed using 12 buffaloes from a total of 20 Murrah buffaloes on an organic farm, with the cow used as a control for herself. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for treatments with pure oil (TTO) and medication containing 5% TTO (O5) were determined. The buffaloes were clinically examined, and the teats were evaluated using thermography and ultrasound. Udder health was monitored during the first 100 days in milk (DIM) using milk somatic cell count (SCC) and California mastitis test (CMT). Laboratory tests against standard strains Staphylococcus aureus ATCC®25,923™, Escherichia coli ATCC®25,922™, and wild bacterial strains showed maximum MIC values of 50 µL/mL for the TTO and O5 treatments. One wild-type S. aureus strain showed no MBC. No adverse effects were observed after the intramammary application of TTO. The CMT and SCC values were similar (P > 0.05) for all observations. The medication containing 5% TTO was effective in vitro and compatible with the intramammary tissue in vivo of Murrah buffaloes. TTO was safe, not inducing inflammatory processes or other modifications of the teat detectable by thermography or ultrasound. It was able to protect buffaloes during the dry period under field conditions, demonstrating potential use as a teat sealant for organic farms.

Modelling the burden of disease for cattle-A case of ticks and tick-borne diseases in cattle in a rural set-up in South Africa.

BACKGROUND: The study aimed to estimate the burden of ticks and tick-borne diseases (TBDs) among rural cattle-keeping households of the Eastern Cape province of South Africa using Productivity Adjusted Life Years (PALYs). We modified Disability Adjusted Life Year (DALY) equations for humans to PALYs to estimate the societal burden of tick-borne animal diseases. Whilst the World Health Organization has indicated the adaptability of DALYs to assess burden of animal diseases, nothing has been done in this regard. This could be due to several reasons including that the assessment of animal disease burden is often less of a priority compared to human diseases, particularly in low- and middle-income countries where resources may be limited. As a result, less funding and attention may be given to developing and implementing PALYs for animal diseases. Furthermore, technical and conceptual challenges may be associated with applying DALYs equations to animal diseases, such as determining appropriate measures of productivity loss for different types and categories of animals and diseases. This motivated our study, which is focused on modelling the burden of ticks and TBDs in cattle (cows, oxen and bulls) reared in resource-poor settings. METHOD: We formulated a PALYs approach for cattle populations by adapting the DALYs approach to assess the burden of ticks and TBDs for cattle populations in 20 villages in the Eastern Cape province of South Africa. PALYs is a measurement used to assess the burden of disease in cattle populations, quantifying the years of life lost due to premature mortality and disability. It encompasses years of life lost due to premature mortality (YLL) and years lost due to disability (YLD) caused by health conditions. PALYs provide a comprehensive perspective on the effective number of years lost due to disability and premature death in cattle populations. The PALYs model involves several parameters that are examined to understand their impact on the model's behavior. To illustrate this, we used a structured questionnaire to collect data on parameters that feed into PALY equations. We coded and entered data from questionnaires directly into Statistical Package of Social Sciences (IBM SPSS Version 20) and entered the estimated values of PALY parameters to calculate PALYs equations, which were to estimate the societal disease burden of ticks and TBDs in cattle. PALYs calculations were done in three categories; PALYs without discounting and age weighting, PALYs with only discounting, and PALYs with discounting and age weighting in a practical example to study how these parameters influence the outcomes of the PALYs model. RESULTS: Our results revealed that the years of productivity lost by a cow, bull, and ox that suffered from ticks and TBDs could be estimated at various disability weights. Approximately 26%, 23% and 35% of the productivity years of a cow, ox and bull, respectively, reared by resource-poor livestock owners are lost due to the burden of ticks and TBDs in the Eastern Cape province of South Africa. However, introducing tick control measures reduces the loss to approximately 3%, 2% and 3% of their lifespan productivity, an indication that tick control will save approximately 23%, 21% and 32% of years of the productive life of cows, oxen and bulls, respectively. Therefore, it is evident that using ticks and TBD prevention measures at an early age of cattle will improve cattle productivity and hence the socioeconomic welfare of resource-poor rural farming communities in the Eastern Cape province of South Africa. CONCLUSION: The findings generated from the PALYs approach are helpful in projections for the future burden of any livestock disease. They may be used as a basis in policy formulation and decision-making by various stakeholders, and hence a priority in animal health economics. We recommend that a classification of livestock diseases of national economic importance should consider both the societal burden (non-monetary) and economic impact instead of the common practice of only considering the economic (monetary) impact. Adding a societal burden measure to existing economic measures provides a holistic understanding of the impact of a disease on society especially in resource-limited settings where the livestock value goes beyond monetary value.

Efficacy of hydroethanolic extract of Randia aculeata seed against the southern cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) on naturally infested cattle under field conditions.

The cattle tick Rhipicephalus (Boophilus) microplus is a major problem of concern for cattle industry in tropical and subtropical areas. Control of cattle tick is based mainly on the use of chemical acaricides, which has contributed to the emerging problem of selection of resistant tick lineages. Plants have been used as an alternative to conventional acaricidal drugs. On the other hand, the acaricidal activity of hydroethanolic extract of Randia aculeata seed (EHRA) has been demonstrated against R. microplus under laboratory conditions. However, the utility of EHRA seed as a potential acaricidal needs to be determined under field conditions. For this reason, the aim of this study was to evaluate the efficacy of the EHRA against R. microplus sprayed on naturally infested calves, determine the effect of the EHRA seed on acetylcholinesterase activity in R. microplus larval and identify the chemical composition of EHRA. Forty-five male calves were divided in three groups and treated with: G1 water; G2 EHRA 20% w/v and G3 coumaphos 0.2% v/v. Acetylcholinesterase (AChE) activity in R. microplus larvae was determined by a colorimetric assay. The chemical composition of EHRA was accessed through HPLC/MS. Significantly fewer ticks were observed after 24 h on the treated group compared to control group. EHRA significantly inhibited in vitro AChE activity in R. microplus at all tested concentrations. Chlorogenic acid, vanillinic acid, p-coumaric acid, caffeic acid. rutin, quercetin, (-)-epicatechin, 4-hydroxybenzoic acid, quercetin, vanillin, 2,4-dimethoxy-6-methylbenzoic acid, scopoletin and ferulic acid were identified in the extract. The results provided new data for the elucidation of the mechanisms of EHRA acaricide action and to further evaluate the use as a new alternative control agent against R. microplus under in vivo conditions.

Characterization of lesions of nutritional congenital goitre in cattle.

There are few studies that classify and characterize the morphometric and immunohistochemical features of goitre in bovine thyroid glands (TGs). We investigated 39 bovine TGs (fetuses [9], stillbirths [18], neonates [12]) born to dams with low T4 hormone levels and no iodine supplementation and 10 (fetuses [3], stillbirths [3], neonates [4]) born to dams with normal T4 levels and supplemented with iodine. Body weight (BW), TG weight (TGW), TGW:BW ratio and histological lesions were determined. The TGs were classified histopathologically as normal gland (G0), mild goitre (G1), moderate goitre (G2) or severe goitre (G3). Various morphological and morphometric parameters were calculated from microscopic images using image analysis software. Immunohistochemistry was performed to detect proliferating cell nuclear antigen (PCNA). There were significant differences in the TGW:BW ratio among groups (P <0.05): 0.3 ± 0.1 in G0, 0.5 ± 0.3 in G1, 0.8 ± 0.3 in G2 and 1.3 ± 0.7 in G3. In G0, large homogeneous follicles with eosinophilic colloid were seen. In the groups with lesions (G1, G2 and G3), heterogeneity in follicle shape and size, height and area of thyroid follicular cells, height of thyroid follicular epithelium and PCNA immunolabelling were directly related to histopathological grade, with significant differences among groups (P <0.001), gradually increasing from G1 to G3 compared with G0. The TGW:BW ratio and histological grade were positively correlated (P = 0.008).