Lactation Number Research Articles

Assessment of Ruminating, Eating, and Locomotion Behavior during Heat Stress in Dairy Cattle by Using Advanced Technological Monitoring.

Heat stress (HS) significantly impacts dairy farming, prompting interest in precision dairy farming (PDF) for gauging its effects on cow health. This study assessed the influence of the Temperature-Humidity Index (THI) on rumination, eating, and locomotor activity. Various parameters, like rumination time, drinking gulps, chews per minute, and others were analyzed. The hypothesis was that precision dairy farming technology could help detect HS. Nine healthy Lithuanian Black-and-White cows were randomly selected for the trial. RumiWatch noseband sensors recorded behaviors, while SmaXtec climate sensors monitored THI. The data collection spanned from 14 June to 30 June. Cows in the THI class ≥ 72 exhibited reduced drinking time (51.16% decrease, p < 0.01), fewer chews per minute (12.9% decrease, p < 0.01), and higher activity levels (16.99% increase, p < 0.01). THI showed an inverse correlation with drinking time (r = -0.191, p < 0.05) and chews per bolus (r = -0.172, p < 0.01). Innovative technologies like RumiWatch are effective in detecting HS effects on behaviors. Future studies should explore the impact of HS on RWS biomarkers, considering factors such as lactation stage, number, yield, and pregnancy.

Impact of Inbreeding and Ancestral Inbreeding on Longevity Traits in German Brown Cows.

A recent study on the population structure of the German Brown population found increasing levels of classical and ancestral inbreeding coefficients. Thus, the aim of this study was to determine the effects of inbreeding depression and purging on longevity traits using classical and ancestral inbreeding coefficients according to Kalinowski (2002) (Fa_Kal, FNew), Ballou (1997) (Fa_Bal), and Baumung (2015) (Ahc). For this purpose, uncensored data of 480,440 cows born between 1990 and 2001 were available. We analyzed 17 longevity traits, including herd life, length of productive life, number of calvings, lifetime and effective lifetime production for milk, fat, and protein yield, the survival to the 2nd, 4th, 6th, 8th, and 10th lactation number, and the culling frequencies due to infertility, or udder and foot and leg problems. Inbreeding depression was significant and negative for all traits but for culling due to udder and to foot and leg problems. When expressed in percentages of genetic standard deviations, inbreeding depression per 1% increase in inbreeding was -3.61 to -10.98%, -2.42 to -2.99%, -2.21 to -4.58%, and 5.13% for lifetime production traits, lifetime traits, survival rates, and culling due to infertility, respectively. Heterosis and recombination effects due to US Brown Swiss genes were positive and counteracted inbreeding depression. The effects of FNew were not significantly different from zero, while Fa_Kal had negative effects on lifetime and lifetime production traits. Similarly, the interaction of F with Fa_Bal was significantly negative. Thus, purging effects could not be shown for longevity traits in German Brown. A possible explanation may be seen in the breed history of the German Brown, that through the introgression of US Brown Swiss bulls ancestral inbreeding increased and longevity decreased. Our results show, that reducing a further increase in inbreeding in mating plans is advisable to prevent a further decline in longevity due to inbreeding depression, as purging effects were very unlikely in this population.

Association between blood miR-26a levels following artificial insemination, and pregnancy outcome in dairy cattle.

Early pregnancy diagnosis is key to maximise productivity of dairy herds. We previously showed that an increase in the levels of miR-26 could be detected as soon as day 8 of pregnancy in heifers. The aims of this study were to determine whether 1) plasma miR-26 levels would be distinctly elevated, retrospectively, early after artificial insemination in lactating cows with successful compared to failed pregnancies, 2) the early increase in miRNA levels in cows with successful pregnancy could be accounted for by changes in miRNA expression in white blood cells (WBCs), presumably induced by the effects of embryo-derived interferon tau (IFNt), and 3) plasma miRNA levels may provide a reliable early predictor of pregnancy that could be used at a herd level. Blood samples were taken from a total of 34 dairy cows (lactation number 1 to 4) before (D0) and 9 and 18 days after artificial insemination at oestrus, followed by confirmation of pregnancy status by ultrasound on D32. In addition, WBCs collected from non-pregnant cows (n = 4) were stimulated in vitro with recombinant ovine IFNt (0-100 pg/ml). Levels of miRNAs and ISG15, a known IFNt-induced gene, were quantified by qPCR. Relative to D0, a larger increase in plasma miR-26a (P = 0.04) occurred on D9 in cows later confirmed to be pregnant (n = 12) than in cows with a failed pregnancy (n = 22). Expression of miR-26a in WBCs was not affected (P>0.1) by pregnancy status or IFNt stimulation in vitro, in contrast to ISG15 expression which increased markedly (P<0.0001) both in WBC samples collected on D18 from animals later confirmed to be pregnant, and in WBCs after stimulation with IFNt in vitro. Finally, ROC analyses revealed that miR-26a on D9 or D18 could predict pregnancy outcome with much lower accuracy than WBC ISG15 on D18 (Likelihood ratio, 2.3 vs 15.4). In summary, a modest increase in plasma miR-26a levels occurs during early pregnancy in mature dairy cows which may not accounted for by changes in miRNA levels in WBCs or the effects of IFNt. Moreover, compared to ISG15, changes in miR-26a levels may not provide an accurate test for early diagnosis of pregnancy in cows.

Influence of an eCG administration on puerperal involution and fertility in Simmentaler cows

In the literature, various methods aiming for a promotion of uterine involution and ovarian function in post-partum dairy cattle have been described. Recently, successful use of equine choriongonadotropin (eCG) in this context has been repeatedly reported, while other studies have failed to demonstrate positive effects of eCG administration on puerperal involution in cows. Due to the contradictory results described in the literature, the aim of this field study was to verify whether the administration of eCG on day 10 post-partum exerts a positive effect on uterine involution, ovarian activity and fertility indices in Simmental cows. In nine dairy farms, 205 Simmental cows were divided by lot into three groups: Group 1 animals received 500 I.U. eCG, group 2 received 50 µg gonadorelin, and group 3 animals received 250 mg butafosfan and 125 µg cyanocobalamin (control group). Treatment was administered on day 10 post-partum in each case. The animals were examined clinically and ultrasonographically on the 10th, 25th and 42nd day post-partum and the time to insemination and pregnancy were recorded. Group comparison with respect to the recorded parameters was initially performed without considering confounding factors by analysis of variance. In the second step, potential influencing variables (lactation, milk yield, change in backfat thickness, retentio secundarium and serverity of the obstetric intervention) were taken into account, as well as the combination of the random factors "farm" and "individual animal within the farm". The administration of eCG exhibited no significant effect on uterine involution, however, the cervical involution was influenced significantly. In the group of cows with eCG treatment, ovarian cysts were detected significantly more frequently on day 25 post-partum (p=0.04). This difference did not persist on the 42nd day post-partum. Neither voluntary waiting period nor the days open were significantly shortened by eCG administration. Lactation number showed a significant effect on uterine involution. Heifers exhibited more rapid involution by day 42 post-partum than cows. Administration of eCG in Simmentaler cows at day 10 post-partum showed no positive effect. The use of eCG in early puerperium to promote fertility in the cow should be avoided.

Impact of varying levels of pasture allowance on the nutritional quality and functionality of milk throughout lactation

The objective of this study was to examine the impact of increasing proportions of grazed pasture in the diet on the composition, quality, and functionality of bovine milk across a full lactation. Fifty-four spring-calving cows were randomly assigned to 1 of 3 groups (n = 18), blocked on the basis of mean calving date (February 15, 2020 ± 0.8 d), pre-experimental daily milk yield (24.70 ± 3.70 kg), milk solids yield (2.30 ± 0.27 kg), lactation number (3.10 ± 0.13), and economic breeding index (182 ± 19). Raw milk samples were obtained weekly from each group between March and November 2020. Group 1 (GRS) consumed perennial ryegrass and was supplemented with 5% concentrates (dry matter basis); group 2 was maintained indoors and consumed a total mixed ration (TMR) diet consisting of maize silage, grass silage, and concentrates; and group 3 consumed a partial mixed ration diet (PMR), rotating between perennial ryegrass during the day and indoor TMR feeding at night. Raw milk samples consisted of a pooled morning and evening milking and were analyzed for gross composition, free amino acids, fatty acid composition, heat coagulation time, color, fat globule size, and pH. The TMR milks had a significantly higher total solids, lactose, protein, and whey protein as a proportion of protein content compared with both GRS and PMR milks. The GRS milks demonstrated a significantly lower somatic cell count (SCC), but a significantly higher pH and b*-value than both TMR and PMR milks. The PMR milks exhibited significantly lower total solids and fat content, but also demonstrated significantly higher SCC and total free amino acid content compared with GRS and TMR. Partial least squares discriminant analysis of fatty acid profiles displayed a distinct separation between GRS and TMR samples, while PMR displayed an overlap between both GRS and TMR groupings. Variable importance in projection analysis identified conjugated linoleic acid cis-9,trans-11, C18:2n-6 cis, C18:3n-3, C11:0, and C18:2n-6 trans as the largest contributors to the variation between the diets. Milk fats derived from GRS diets exhibited the highest proportion of unsaturated fats and higher unsaturation, health-promoting, and desaturase indices. The lowest proportions of saturated fats and the lowest atherogenic index were also exhibited by GRS-derived milk fats. This work highlights the positive influence of grass-fed milk for human consumption through its more nutritionally beneficial fatty acid profile, despite the highest milk solid percentages derived from TMR feeding systems. Furthermore, this study demonstrates the proportional response of previously highlighted biomarkers of pasture feeding to the proportion of pasture in the cow's diet.

A time series analysis of milk productivity in US dairy states

As US dairy cow production evolves, it is important to characterize trends and seasonal patterns to project amounts and fluctuations in milk and milk components by states or regions. Hence, this study aimed to (1) quantify historical trends and seasonal patterns of milk and milk components production associated with calving date by parities and states; (2) classify parities and states with similar trends and seasonal patterns into clusters; and (3) summarize the general pattern for each cluster for further application in simulation models. Our data set contained 9.18 million lactation records from 5.61 million Holstein cows distributed in 17 states during the period January 2006 to December 2016. Each record included a cow's total milk, fat, and protein yield during a lactation. We used time series decomposition to obtain each state's annual trend and seasonal pattern in milk productivity for each parity. Then, we classified states and parities with agglomerative hierarchical clustering into groups according to 2 methods: (1) dynamic time warping on the original time series and (2) Euclidean distance on extracted features of trend and seasonality from the decomposition. Results showed distinguishable trends and seasonality for all states and lactation numbers for all response variables. The clusters and cluster centroid pattern showed a general upward trend for all yields [energy-corrected milk (ECM), milk, fat, and protein] and a steady trend for fat and protein percent for all states except Texas. We also found a larger seasonality amplitude for all yields (ECM, milk, fat, and protein) from higher lactation numbers and a similar amplitude for fat and protein percent across lactation numbers. The results could be used for advising management decisions according to farm productivity goals. Furthermore, the trend and seasonality patterns could be used to adjust the production level in a specific state, year, and season for farm simulations to accurately project milk and milk components production.

Mastitis in a flock of milking sheep.

Determination of somatic cell counts (SCC) becomes more and more important also for ewe's milk. SCC can be a useful indicator of milk quality for milk processors while it can be a mastitis indicator for sheep keepers and an important selection criterion for breeders. The objective of our study was to acquire basic information about factors influencing SCC variability in lambing ewes of the Tsigai (T) and Improved Valachian (IV) breeds. Somatic cell counts (SCC) were determined in 866 milk samples in 2017 and 2018, during lamb sucking and during milking period. An instrument Fossomatic 90 (Foss Electric, Hillerød, Denmark) was used for analysis. Average SCC varied from 270 to 1897 × 103 cells/ml during lamb sucking and from 268 to 2139 × 103 cells/ml during milking period. Differences between the sampling periods were statistically significant in 2017. An increase in SCC was observed at the end of both sucking and milking periods. An overall evaluation of lactation brought about the average SCC at 364 × 103 cells/ml in 2017 (log(10) SCC - 2,25) and at 1,091 × 103 cells/ml in 2018 (log(10) SCC - 2,68). The indicator log(10) was significantly influenced by breed in 2017 (T - 2,61; IV - 2,75). The effect of lactation number and number of sucking lambs did not have any significant influence on SCC.

LINEAR EVALUATION OF HOLSTEIN BULLS BY THE EXTERIOR TYPE OF THEIR DAUGHTERS IN "OSTRIYKOVSKE" LLC

Introduction. In the context of intensive milk production technologies, the dairy farming industry faces high demands on animal health, constitutional strength and manufacturability due to mechanization and full automation of production processes. Modern methods of breeding involve the creation of highly productive animals that are well adapted to the least costly production technologies, taking into account an objective assessment of their breeding qualities and the application of population genetics.&#x0D; Materials and methods of research. The study was conducted based on the materials of primary breeding records in the farm "Ostriykivske" LLC, Kyiv region. Evaluation of the milk production of cows was carried out for 305 days of the last completed lactation on the basis of the database of the dairy farming management system (Intersel-Orsek). An eyeball assessment of the exterior of the firstborn heifers was carried out according to the instructions for boning in the modification of Y. P. Polupan and the method of linear classification by type. The exterior of the animals was studied by taking the main 17 measurements at 2–5 months of lactation.&#x0D; The cow type was evaluated using two systems: a linear description of individual exterior traits; evaluation of complex traits on a 100-point scale. The total score was calculated based on complex traits, which in turn were based on linear descriptive traits. In the process of evaluating the animals, the results were recorded in the evaluation sheet for dairy and dairy-meat cows by body type, pre-recording the animal's identification number, nickname, date of birth, date of calving, and lactation number. A total of 114 first-born Holstein cows were evaluated at Ostriykivske LLC.&#x0D; Research results In the herd of Ostriykivske LLC, the best score for the complex of traits was obtained by the daughters of the bull sire Lobby 101916210 of the Eleweishna 1491007 line (83.2 points), which corresponds to "good with a plus". The daughters of the bull sire Kingly 101409948 of the H. H. Starbuck 352790 line received the lowest score – 78.0. The lowest score for the complex of limb traits was observed in the daughters of the bull Sleman 7817774 of the Valiant 1650414 line (70.5 points), and the highest in the descendants of Lobby 101916210 – 79.3 points. The variability of scores for udder traits ranged from 76.2 points in the daughters of Tandem 9434213 to 80.8 points in the daughters of Lobby 101916210 with a difference of 4.6 points between these extreme variants.&#x0D; In addition, the evaluated cows have undesirable development of certain appearance traits, such as additional teats, close proximity of the hind teats, rudiments behind the teats, underdeveloped udder lobes, and diseased limbs. Thus, the use of the linear classification methodology allows you to obtain information about the features of the body structure, identify the advantages and disadvantages of cattle.&#x0D; Such quantitative traits as milk yield, milk fat and protein yield are economically important for dairy producers. The obtained results of the research show that the best score for the complex of traits (83.2 points) and the highest milk yield (milk yield – 10560 kg; fat – 3.92%; protein – 3.15%) are observed in daughters of the bull of the sire Lobby 101916210 of the line Eleveishna 1491007.65. It was found that the firstborn cows with the best type indices are characterized by high milk production. Selection of the best performers by linear evaluation by type for the repair of the dairy herd of firstborn cows will provide more functional reliability and high milk production.&#x0D; Conclusions. Thus, the use of the linear classification methodology in dairy cattle breeding allows to objectively determine the characteristics of cows by type of appearance, and the existence of a relationship between milk production and group linear traits is the key to the effectiveness of animal selection by type of appearance.

Short communication: The biological value of transition milk: analyses of immunoglobulin G, IGF-I and lactoferrin in primiparous and multiparous dairy cows.

Colostrum (the first mammary gland secretion after calving) is known to contain high concentrations of nutrients as well as bioactive substances (including immunoglobulins, growth factors, and antimicrobial factors) to ensure neonatal survival. Due to its immunomodulatory, antibacterial, and antiviral activities, bovine colostrum has been used not only in calves but also in the prevention and treatment of human gastrointestinal and respiratory infections. Transition milk is the mammary secretion from the second milking to the sixth, which may contain these bioactive compounds to a lesser extent. The objective of the present study was to measure IGF-I, immunoglobulin G (IgG), and lactoferrin (LTF) concentrations in colostrum and transition milk of primiparous and multiparous cows to further assess its potential use in veterinary and nutraceutical applications. The results demonstrated that the concentrations of these three bioactive molecules decrease from the first milking to the tenth. Concentrations of IGF-I and LTF were greater in multiparous than in primiparous cows. Also, lactation number interacted with milking number in IGF-I, since primiparous cows had a smoother decline of IGF-I concentrations than multiparous ones. Overall, transition milk from the second milking showed a 46% decrease in the analysed colostrum bioactive molecules. Therefore, further studies are needed to apply this knowledge in neonate farm management practices or in developing pharmaceutical supplements from farm surpluses.

Türkiye’de Herdbook Sistemine Kayıtlı Esmer, Simental ve Siyah Alaca Sığır Irkları ile Melezlerine ait Süt Verimi Özellikleri Üzerine bir Araştırma

This study was conducted to examine the milk yield traits of Holstein Friesian (HF), Brown Swiss (BS), and Simmental (SM) breeds, as well as their crossbreeds raised in enterprises registered in the herdbook system in Türkiye. With this study, the performances of cattle breeds and their crossbreeds widely raised in Türkiye were compared in terms of milk yield characteristics based on agricultural regions of Türkiye. The data used in the study included the completed lactation records of 22 331 heads of cattle for the years 2000-2014. The GLM ANOVA method was used in the statistical analysis of the effects of breed, genotype, and region on traits related to milk yield. Across the herd, the mean and standard deviation values were determined as 7551±2771 kg for lactation actual milk yield (AMY), 4.2±1.8 for total lactation number (TLN), and 382.9±9.2 days for lactation period (LP). The effects of genotypes and regions were found to be significant or very significant (p&amp;lt;0.05 or p&amp;lt;0.001) for all three studied traits, region x genotype interaction was found to be very significant for AMY and TLN (p&amp;lt;0.001), and not significant for LP (p=0.184). As a result, it was revealed that the interaction effects of genotype, region, and genotype x region should be taken into account in determining the milk yield traits of cultured breed and crossbreed cows that are widely raised in Türkiye. Accordingly, it was concluded that the interaction findings should be evaluated in determining the breed preferences by the regions.

Economic valuation of zootechnical indicators in a tropical dairy goat production system

The objective of our study was to promote advances in the economic valuation method of zootechnical indicators in dairy goat farming by incorporating the analysis of the modeling of biological relationships between the indicators. A Multiple Linear Regression model was developed to predict milk production as a function of zootechnical indexes and to determine which indicators influenced and in what proportion the quantity of liters sold. The absolute and relative economic values of these indicators were then calculated. Milk production was influenced by prolificacy (P=0.00325), age at kidding (P=0.01886), duration of lactation (P=&lt; 2e-16) and parity number (P=0.00575), with absolute and relative economic values respectively as follows: $ 0,086/kid/female/year and 62.3% for prolificacy, -$ 0.001/female/month and -0.5% for age at kidding, $ 0.002/female/day and 1.5% for duration of lactation, and $ 0.051/female/parity and 36.7% for parity number. High values for the age at first kidding and interval between kiddings may be responsible for the effect of age and parity number. In conclusion, the procedures were herein employed and validated to improve the economic valuation method proved to be viable and efficient for application in dairy goat farming. In the situation analyzed, more than 90% of the economic value was obtained by prolificacy and parity number; however, the scarcity of research on these aspects of goat farming and the different indicators analyzed demonstrate the need for continuity of research in order to improve the methods so that their use in the field is applicable in more accessible ways.

WPŁYW KOLEJNEJ LAKTACJI ORAZ ŚREDNIEJ DOBOWEJ WYDAJNOŚCI MLEKA W LAKTACJI PEŁNEJ KRÓW RASY POLSKIEJ HOLSZTYŃSKO-FRYZYJSKIEJ NA DŁUGOŚĆ OKRESU ZASUSZENIA

The aim of the study was to determine the effect of average daily milk yield in complete lactation and lactation number in cows producing at least 8,500 kg of milk in 305-day lactation on the length of the dry period before the next lactation. A total of 1,965 complete, extended lactations in Polish Holstein-Friesian cows subject to use value assessment were analysed. The average complete-lactation daily milk yield was shown to influence the length of the dry period. The average dry period length was 44 days. Dry period length decreased in successive milk-yield groups, from 50 days (average daily yield up to 25 kg of milk) to 28 days (average daily yield over 35 kg in complete lactation). Thus it was confirmed that as milk yield increased, it was more difficult to end lactation. The shortest dry period (only 25 days) was recorded in the youngest cows (second and third lactation) with the highest average daily milk yield in complete lactation (&gt;35 kg). In the oldest cows, i.e. those in their sixth lactation and higher, no statistically significant differences were shown in the length of the dry period depending on daily yield.

Comparative productive performance of cows born through embryo transfer, artificial insemination and natural mating in dairy and dual-purpose herds raised in tropical conditions.

A populational, observational and longitudinal-retrospective study with records of 28 dairy specialized and dual-purpose farms, was carried out to compare the productive performance of cows born by embryo transfer (ET), artificial insemination (AI), and natural mating (NM), using the database of Centro Regional de Investigación para la Producción Animal Sostenible (CRIPAS) of cattle herds in Costa Rica. Herds (system × altitude), conception method (ET, AI and NM), genetic background (DSpB: specialized dairy breeds (Bos taurus) and crosses, GYR×HOL: Gyr × Holstein Crossbred and DSpB×BI: crosses between dairy breeds and Bos indicus), year of birth (or at calving), lactation number and days in milk were evaluated for the productive parameters age at first calving (AFC), calving to conception interval (CCI) and lactation milk yield (LMY) using a GLIMMIX procedure on SAS. The AFC, CCI, and LMY were affected (P<0.0001) by all factors considered in each parameter. ET has lower (P<0.0001) AFC in months (33.1) than AI (35.2) and NM (36.44). NM had lower (P=0.004) CCI (110 d) than AI or ET (121 d) values which were similar (P>0.05). The higher LMY (P<0.0001) was observed in ET (4140 kg), compared to AI (3706 kg) and NM (3595 kg). There was no difference between AI and NM. In conclusion, the method of conception in calves affected their future reproduction and production during puberty, postpartum, and lactation. The effects on management decisions will require a rigorous economical study to discern whether ET would be a cost-effective alternative to AI or NM.

Hepatic Global Transcriptomic Profiles of Holstein Cows According to Parity Reveal Age-Related Changes in Early Lactation.

Cows can live for over 20 years, but their productive lifespan averages only around 3 years after first calving. Liver dysfunction can reduce lifespan by increasing the risk of metabolic and infectious disease. This study investigated the changes in hepatic global transcriptomic profiles in early lactation Holstein cows in different lactations. Cows from five herds were grouped as primiparous (lactation number 1, PP, 534.7 ± 6.9 kg, n = 41), or multiparous with lactation numbers 2-3 (MP2-3, 634.5 ± 7.5 kg, n = 87) or 4-7 (MP4-7, 686.6 ± 11.4 kg, n = 40). Liver biopsies were collected at around 14 days after calving for RNA sequencing. Blood metabolites and milk yields were measured, and energy balance was calculated. There were extensive differences in hepatic gene expression between MP and PP cows, with 568 differentially expressed genes (DEGs) between MP2-3 and PP cows, and 719 DEGs between MP4-7 and PP cows, with downregulated DEGs predominating in MP cows. The differences between the two age groups of MP cows were moderate (82 DEGs). The gene expression differences suggested that MP cows had reduced immune functions compared with the PP cows. MP cows had increased gluconeogenesis but also evidence of impaired liver functionality. The MP cows had dysregulated protein synthesis and glycerophospholipid metabolism, and impaired genome and RNA stability and nutrient transport (22 differentially expressed solute carrier transporters). The genes associated with cell cycle arrest, apoptosis, and the production of antimicrobial peptides were upregulated. More surprisingly, evidence of hepatic inflammation leading to fibrosis was present in the primiparous cows as they started their first lactation. This study has therefore shown that the ageing process in the livers of dairy cows is accelerated by successive lactations and increasing milk yields. This was associated with evidence of metabolic and immune disorders together with hepatic dysfunction. These problems are likely to increase involuntary culling, thus reducing the average longevity in dairy herds.

Prevalence of Dichelobacter nodosus and Fusobacterium necrophorum on dairy farms in Slovakia

ABSTRACT The aim of this study was to determine the prevalence of bacteria Dichelobacter nodosus (D. nodosus) and Fusobacterium necrophorum (F. necrophorum) in non-lame dairy cows on eight Slovak dairy herds. In total, 1,631 Holstein Friesian dairy cows were included in the study. Information of the cows was collected from on-farm software included cow ID, lactation number (heifer/cow), year milk yield (kg), and DIM on collection date. The PCR method detected D. nodosus and F. necrophorum on the feet of 1,394 (85.5%) and 373 (22.1%) dairy cows, respectively (p < 0.05). No dairy farm could be found without positive samples for D. nodosus and the majority of the farms were free or had very low prevalence of F. necrophorum (0–9.1%). Statistical difference for the prevalence of D. nodosus and F. necrophorum in different Slovak regions was detected for both strains. Logistic regression revealed an association between both D. nodosus and F. necrophorum identification and annual milk production (odds ratios = 0.69 and 0.32, respectively). Our data demonstrates that D. nodosus is present on the feet of almost every dairy cow what means a potential risk for cattle to develop foot rot. Furthermore, both bacteria are associated with decreased annual milk production.

Evaluation of test-day milk somatic cell count to predict intramammary infection in late lactation grazing dairy cows

Use of selective dry cow antimicrobial therapy requires to precisely differentiate cows with an intramammary infection (IMI) from uninfected cows close to drying-off to enable treatment allocation. Milk somatic cell count (SCC) is an indicator of an inflammatory response in the mammary gland and is usually associated with IMI. However, SCC can also be influenced by cow-level variables such as milk yield, lactation number and stage of lactation. In recent years, predictive algorithms have been developed to differentiate cows with IMI from cows without IMI based on SCC data. The objective of this observational study was to explore the association between SCC and subclinical IMI, taking cognizance of cow-level predictors on Irish seasonal spring calving, pasture-based systems. Additionally, the optimal test-day SCC cut-point (maximized sensitivity and specificity) for IMI diagnosis was determined. A total of 2,074 cows, across 21 spring calving dairy herds with an average monthly milk weighted bulk tank SCC of ≤200,000 cells/mL were enrolled in the study. Quarter-level milk sampling was carried out on all cows in late lactation (interquartile range = 240-261 d in milk) for bacteriological culturing. Bacteriological results were used to define cows with IMI, when ≥1 quarter sample resulted in bacterial growth. Cow-level test-day SCC records were provided by the herd owners. The ability of the average, maximum and last test-day SCC to predict infection were compared using receiver operator curves. Predictive logistic regression models tested included parity (primiparous or multiparous), yield at last test-day and a standardized count of high SCC test-days. In total, 18.7% of cows were classified as having an IMI, with first parity cows having a higher proportion of IMI (29.3%) compared with multiparous cows (16.1%). Staphylococcus aureus accounted for the majority of these infections. The last test-day SCC was the best predictor of infection with the highest area under the curve. The inclusions of parity, yield at last test-day, and a standardized count of high SCC test-days as predictors did not significantly improve the ability of last test-day SCC to predict IMI. The cut-point for last test-day SCC which maximized sensitivity and specificity was 64,975 cells/mL. This study indicates that in Irish seasonal pasture-based dairy herds,with low bulk tank SCC control programs, the last test-day SCC (interquartile range days in milk = 221-240) is the best predictor of IMI in late lactation.

Milk Yield and Composition, Technological Properties and Homeostasis Indices at Different Lactation Stages and Parities of Two Polish Dairy Goat Breeds

Abstract The purpose of the research was to determine the effect of breed, lactation number, and lactation stage on milk efficiency and goat milk ingredients, these being indicators of milk technological parameters and homeostasis disturbances. Goat breed and number of lactation affected energy-corrected milk, value-corrected milk yield, fat corrected milk, protein, casein, lactose contents and free fatty acids. Additionally, differences in non-fat solids and urea contents were found between two Polish common dairy breeds White Improved (PWI) and Fawn Improved (PFI) goats. Moreover, parity affected milk yield, its acidity and somatic cell count (SCC). Milk yield and milk components were found to vary according to lactation stage. At the beginning of lactation, milk is richer in ingredients which have effect on cheese and yoghurt production. All the goats undergo similar changes related to the lactation stage that is at the same time and this can affect the yield and quality of the curd. In production focused on liquid milk, the age structure of the herd should be properly managed, as the goats in their third lactation or above have higher milk yields, regardless of breed. For cheese production, the PWI breed would be more suitable than PFI as the PWI goat milk contains less SCC and more components essential for milk processing, including caseins.

A Review of Genetic and Non-Genetic Parameter Estimates for Milk Composition of Cattle

This review focuses on the genetic and non-genetic parameter estimation for dairy cattle milk composition. Milk is the most widely consumed food in the world, containing proteins, fats, lactose, and various vitamins and minerals. Milk's solids content has a direct impact on both its nutritional and economic value. The milk composition trait performances had obtained in the range from 3.5±0.0038 to 6.1±0.05 for fat percentage, 3.07±0.03 to 4.7±0.09 for protein percentage, 3.3 to 5.52±1.71 for lactose content, 12.16±0.14 to 16.02±0.05 for total solid content and 8.47±0.1 to 9.37±0.24 for the solid not fat content of cow milk, respectively. The composition of cow milk is influenced by breed, animal age and health, lactation phase, nutrition, season, milking method, number of lactations, and individual cows. The heritability of milk composition trait ranged from 0.24 to 0.49±0.03 for fat percentage, 0.28 to 0.53±0.009 for protein percentage, 0.41±0.04 to 0.59 for total solid content and 0.17 to 0.68 for the solid not fat content of cow milk, respectively. The repeatability of fat, protein, total solid and solid not fat percentage of bovine milk ranged between 3.9 to 0.98, 0.4 to 0.99, 0.49 to 0.99 and 0.23 to 0.78, respectively. The genetic and phenotypic correlation between fat and solid not fat of cow milk were weakly positive (0.16±0.15, 0.06 ±0.04), whereas a strong positive relationship was found between protein content and solid not fat of cow milk (0.99±0.05, 0.67±0.03), respectively. Enhancing milk compositional quality through genetic selection based on individual performance is successful.

Important Steps to Decrease the Incidence of Women's Breast Cancer

Breast cancer is a disease occurring once cells in the organ's tissues grow and split in an abandoned process known as a tumor. Despite recent significant advances in diagnosis and treatment, breast cancer remains a problem for societies and individuals. There are several reasons for this, including a lack of information about the mechanism and heterogeneity of breast carcinogenesis cases, despite developments in the treatment modes like hormone therapy, chemo-radiotherapy and surgery. The female human organs' breasts, lobules, ducts and nipples are colonized by a range of bacteria throughout lactation time and numbers of those can yield carcinogenesis and/or stimulate inflammatory processes. Effective prevention programs decrease the occurrence of this cancer by protecting and defending women from evolving cancer disease and avoiding its return by reducing the occurrence of breast cancer by more than 11%, through breastfeeding as an essential protective factor in prevention programs. This article introduces protective steps that may reduce breast cancer occurrence, by expressing women's breast milk using a breast pump device for drawing milk at least annually and using appropriate antibiotics for women who don't breastfeed.

Analysis of The Effect of Region, Province and Breed on Somatic Cell Count in Dairy Cattle in Turkey By Regression Tree Method

This study aimed to determine the effect of various environmental factors on the somatic cell count (SCC) in cow’s milk. The material of the study consisted of an SCC analysis result obtained from 207.614 raw milk samples collected from 65.288 head cattle had different breeds, ages, lactation number, and lactation length between May and December in 2019. They were raised on 6,305 dairy farms that are members of the Cattle Breeders Association (CBAT). In order to determine the effect of region, city, and cattle breed on SCC in raw milk of cattle, a regression tree was created using the Chi-square Automatic Interaction Detection (CHAID) algorithm, a Data Mining (DM) method. Accordingly, the mean SCC value of all enterprises was determined as 201.253 cells/mL. In this study, it was found that the region, city and breed groups with the highest average somatic cell counts were CAR, MSR, MR and SAR region group (285.430 cells/mL); C09, C45, C20, C64, C48, C43 city group (266.744 cells/mL); and HF, MC, and BS breed group (295.705 cells/mL). As a result of this study, the variables affecting SCC were determined as region, city, and breed respectively, in order of importance. Keywords: CHAID; Dairy cattle; Somatic cell count