Cow Characteristics Research Articles

Management factors affecting milk yield, composition, and quality on smallholder dairy farms

A cross-sectional study on 156 smallholder dairy farms in Rwanda was carried out to assess the association between farm management practices and milk yield and quality. A pre-tested questionnaire was used to collect data on cow characteristics and farm management practices. Milk yield was recorded at household level, milk composition was monitored using a Lactoscan device (Milk Analyzer). Somatic cell count (SCC) was determined using a DeLaval cell counter (DCC). A Delvotest SP-NT kit was used to determine antibiotic residues in raw milk. Most dairy cows were kept in zero-grazing system (84.6%) and most farmers had less experience of dairy production (78.2%). Mean daily milk yield was 3.9 L/cow and was associated with type of breed, milking frequency, stage of lactation, and parity. Mean milk content of protein, fat, lactose and solid non-fat, and density were normal and showed no association with different management practices. Based on SCC analyses, 65.8% of the milk samples with less than 300,000 cells/mL were graded as acceptable for delivery to a milk collection centre (MCC) and 12.9% of the samples tested positive for antibiotic residues. These findings suggest low milk yields on smallholder farms in Rwanda that are attributable to type of breed and prevalent high level mastitis, among other factors. The results also indicate possible non-compliance with withdrawal periods, resulting in antibiotic residues in milk, which has public health implications for consumers. Routine testing at MCC for both SCC and antibiotic residues is important for quality control.

Sensory Characteristics of Cow's Milk Yogurt with the Addition of Kecombrang Stem Extract

Sensory Characteristics of Cow's Milk Yogurt with the Addition of Kecombrang Stem Extract

Consequences of weaning and separation for feed intake and milking characteristics of dairy cows in a cow-calf contact system.

In cow-calf contact (CCC) systems breaking the maternal bond may induce stress for the cow, thereby affecting feed intake, milk yield, milk flow rate, and milk electrical conductivity. This study aimed to determine the consequences of weaning and separation strategies in CCC systems for feed intake and milking characteristics of the cow. In 2 experiments, Swedish Holstein and Swedish Red cows either had (experiment 1) whole-day CCC (CCC1, n = 12) for 8.5 ± 1.2 wk (mean ±SD) followed by 12 h of daytime CCC for 8 wk, before abrupt weaning and separation at 16.4 ±1.2 wk, or (experiment 2) whole-day CCC for 16 ± 1.0 wk; thereafter half of the calves were weaned via nose flaps for 2 wk (NF, n = 10) before physical separation and half via nose flaps for 1 wk and fence-line contact for 1 wk (NFFL, n = 9). Cows were compared with conventionally managed cows (CONV1 or CONV2 in experiment 1 or 2) separated from their calves within 12 h postpartum. In experiment 1, the study period included the week before and after the system switch from whole-day to daytime CCC, and the week before and after separation. In experiment 2, the study period included the week before the start of weaning, during weaning, and 1 week after separation. All cows were milked in the same automatic milking unit. In experiment 1, feed intake of CCC1 cows at separation tended to be lower than CONV1 cows. In experiment 2, roughage intake of NF, NFFL, and CONV2 cows did not differ, but the concentrate intake of NF cows was lower than that of CONV2 cows. In experiment 1, the system switch did not affect milking characteristics. However, after separation, machine milk yield and milk electrical conductivity of CCC1 cows increased, remaining lower than CONV1 cows. In experiment 2, machine milk yield of NF and NFFL cows increased when calves were fitted with nose flaps, but remained lower than CONV2 cows. In the week after separation, milk yield of NFFL cows was similar to that of CONV2 cows, and the NF cows remained lower. In the week before weaning, milk flow rates of NF cows were lower than those of CONV2 cows, and the NFFL cows did not differ. Before weaning, milk electrical conductivity of NF and NFFL cows was lower than that of CONV2 cows, but not thereafter. In conclusion, machine milk yield of CCC cows remained lower either until the week of separation, for NFFL cows, or until 3 or 11 wk after weaning and separation for CCC1 and NF cows of experiments 1 and 2, respectively. Cow-calf contact reduced milk electrical conductivity, and milk and peak milk flow rates increased the week after separation of cow and calf. Not for experiment 2, but for experiment 1, cow roughage and concentrate intake decreased at separation and recovered within a week, indicating that abrupt separation exerted a greater impact on the cow than separation after nose flap weaning or fence-line contact. Future studies should compare both weaning strategies within the same experimental setup, also focusing on the consequences for calves.

Seasonal Distribution of Births in Anatolian Buffaloes and Effects of the Season on Some Milk and Reproductive Traits of Cows and Growth Traits of Calves

The aims of this study were i) to evaluate the seasonal changes in births of Anatolian buffaloes, ii) to examine the changes of some milk [lactation milk yield (LMY) and lactation length (LL)] and fertility [first calving age (FCA) and calving interval (CI)] according to seasons and iii) to investigate the effects of seasons on the growth traits of calves [birth weight (BW0), live weight at 6 mo (LW6) and live weight at 12 mo (LW12)]. A total of 8614 to 15605 yield records were evaluated including milk yield and fertility traits of buffalo cows and growth traits of calves between 2012 and 2023. The mean temperature, relative humidity, the duration of sunshine, and temperature humidity index (THI) values were calculated for these years. While the highest birth rate was observed in the summer season (34.27%), the lowest birth rate was determined in the winter season (11.99%). The BW0, LW6 and LW12, LMY, LL, FCA, and CI values of the calves were determined as 30.8±0.04 kg, 107.6±0.23 kg, 172.6±0.27 kg, 994.7±2.05 kg, 262.6±0.22 d 1175.5±3.46 d and 561.7±1.84 d, respectively. Except for CI, all characteristics were significantly affected by seasonal changes (P<0.001). The growth traits of the calves born in autumn were higher than the other seasons. The LMY values in spring and winter were higher than those determined in the different seasons. Also, the highest FCA was obtained in heifers born in the winter. It was concluded that the season could affect both some fertility and milk yield characteristics of buffalo cows and the growth performance of calves.

Assessment of tolerance in dairy cows of the “sv” product for dry hoof baths

The development and implementation of safe, effective means of preventing and treating diseases of the distal extremities of cattle has important veterinary, zoohygienic and economic significance. At present, the participation of saprophytic and opportunistic microorganisms and their associations in the occurrence and spread of infectious diseases of the fingers and hooves in cattle has been established. An important stage in conducting clinical trials of a new drug is studying the tolerability of its increased doses in all target species of animals for which it is intended according to the instructions. The physiological characteristics of cows associated with the birth of calves and milk production limit the range of effective medicines (antibiotics, NSAIDs, etc.) used for this category of productive animals, which creates certain difficulties in organizing therapeutic and preventive measures. In this regard, a promising direction is the use of a new product “SV” (without restrictions on milk) for dry hoof baths, developed at the Federal State Budgetary Institution “FCTRB -VNIVI” for the prevention and treatment of the initial stages of diseases of the distal limbs of cattle. The results of studying the tolerability of the “SV” product in cows with single and repeated use indicate that the developed product does not have an undesirable negative effect on the clinical status, productivity, hematological, biochemical and pathomorphological parameters of experimental animals. The cows tolerated the effect of the product well; there was no decrease in milk yield and quality of milk, damage to the integrity of the skin and hoof horn, or any allergic reactions. The research results obtained confirm the safety of using the “SV” product for dry baths in practice in the recommended dosage regimen and the prospects for extensive production tests.

Stage-Specific Milk Yield Losses and Associated Sweating, Respiration, and Rectal Temperature Responses Under Varying THI Thresholds in Lactating and Dry Cows

Heat stress (HS) may result in changes in the behavior, endocrine system, and physiological characteristics of dairy cows, and it may even lead to death in severe cases. As the effects of global warming have become more notable, the prevalence of HS has increased among dairy cows. Therefore, comprehensive strategies, including not only cooling measures but also dietary adjustments and genetic improvements for heat tolerance, are required to help these animals regulate their body temperature and avoid HS. In addition, detecting HS signs is essential for both lactating and dry cows to ensure appropriate interventions. The temperature-humidity index (THI) is a widely used tool for evaluating the effects of HS on livestock. Since the physiological state of cattle significantly influences their responses to HS, it is imperative to establish specific THI thresholds for both lactating and dry cows to implement appropriate cooling regimens and optimize animal welfare. In this study, we used the THI to investigate the relationship between rectal temperature (RT), respiration rate (RR), and sweating rate (SR) in lactating and dry cows. We also explored the relationships between milk yield at different lactation stages and THI thresholds. The results indicated that lactating and dry cows had different THI thresholds based on their immediate physiological responses. Compared with lactating cows, dry cows had higher THI thresholds for RT, RR, and SR. In addition, cows in early-, intermediate-, and late-lactation stages under thermoneutral conditions produced significantly more milk than did those under mild, moderate, and severe HS conditions, indicating that milk yield losses occur under HS conditions. Taken together, these findings provide valuable insights into how HS can be mitigated in subtropical dairy farms. For lactating cows, implementing cooling measures is recommended when the THI reaches 66 to 67, whereas for dry cows, waiting until the THI reaches 73 is recommended. Milk yield losses may occur when lactating cows are under HS conditions. Therefore, appropriate cooling measures should be implemented at accurate THI thresholds to ensure optimal animal welfare for both lactating and dry cows.

YOLOX-S-TKECB: A Holstein Cow Identification Detection Algorithm

Accurate identification of individual cow identity is a prerequisite for the construction of digital farms and serves as the basis for optimized feeding, disease prevention and control, breed improvement, and product quality traceability. Currently, cow identification faces challenges such as poor recognition accuracy, large data volumes, weak model generalization ability, and low recognition speed. Therefore, this paper proposes a cow identification method based on YOLOX-S-TKECB. (1) Based on the characteristics of Holstein cows and their breeding practices, we constructed a real-time acquisition and preprocessing platform for two-dimensional Holstein cow images and built a cow identification model based on YOLOX-S-TKECB. (2) Transfer learning was introduced to improve the convergence speed and generalization ability of the cow identification model. (3) The CBAM attention mechanism module was added to enhance the model’s ability to extract features from cow torso patterns. (4) The alignment between the apriori frame and the target size was improved by optimizing the clustering algorithm and the multi-scale feature fusion method, thereby enhancing the performance of object detection at different scales. The experimental results demonstrate that, compared to the traditional YOLOX-S model, the improved model exhibits a 15.31% increase in mean average precision (mAP) and a 32-frame boost in frames per second (FPS). This validates the feasibility and effectiveness of the proposed YOLOX-S-TKECB-based cow identification algorithm, providing valuable technical support for the application of dairy cow identification in farms.

154 Forage intake, digestibility, and ruminal fermentation characteristics of beef cows supplemented with a Bacillus-based probiotic

Abstract The aim of this study was to evaluate the influence of a Bacillus-based probiotic supplementation on intake, digestibility, and ruminal fermentation parameters of beef cows consuming a low-quality forage diet (7.0% CP, 60% NDF, 39% ADF, DM basis). Ruminally fistulated Angus × Hereford cows [n = 15; age = 6.1 ± 1 yr; body weight (BW) = 655 ± 57] were used in two identical complete randomized designs, housed in individual pens with water, and forage intake monitored daily. Treatments consisted of 1) 500 g of protein supplement (dry distillers grain + mineral mix) without probiotic (CON n = 15), and 2) 500 g of protein supplement + 3 g of a probiotic containing Bacillus licheniformis and B. subtilis (BOV; n = 15; 2.2 ×109 CFU of the mixture/g; Bovacillus, Novonesis, Hørsholm, Denmark). Each experimental period lasted 33 d, consisting of 21 d of adaptation, 12 d of collection, and 30 d of wash-out between periods. From d 22 to 26, fecal samples were collected to determine intake and nutrient digestibility using titanium dioxide as an indigestible marker. On d 27, ruminal fluid was collected at h 0 (before feeding), 4, 8, 12, 16, and 20 post-feeding to evaluate short-chain fatty acid (SCFA) and N-NH3 concentration. From d 28 to 32, hay samples (4 g) were fitted in Dracon bags and incubated in the rumen for 0, 12, 24, 48, 72, 96, and 120 h to determine nutrient digestibility. Cows receiving BOV had greater (P < 0.001) dry matter intake compared with the CON group (Table 1). Also, cows supplemented with BOV had greater (P < 0.02) dry matter and protein digestibility and a tendency (P ≤ 0.07) for greater NDF and ADF forage digestibility compared with CON. A tendency was also detected (P = 0.09) for the degradability of forage dry matter, which was improved in BOV vs. CON. No effects were observed on rumen fermentation characteristics (P ≥ 0.14; Table 2).). In conclusion, adding bacillus-based probiotics enhanced the intake, nutritional digestibility, and degradability of beef cows fed medium-quality forage diets.

Influence of non-genetic factors on milk production traits of Gangatiri cattle in Varanasi district of Uttar Pradesh

Research was carried out to examine the influence of non-genetic factors on the milk production characteristics of Gangatiri cows. The study was analyzed from 1254 Gangatiri cows across three tehsils (Pindra, Rajatalab, and Sadar) in Varanasi, Uttar Pradesh. The objective was to ascertain the effects of a number of variables on lactation duration, daily milk production, and lactation milk production including the area, calving season, farmer's economic background, parity, and age at first calving. The overall average means for lactation milk production, daily production of milk, and lactation period were discovered to be 794.6413 kg, 3.956 kg, and 203.8327 days, respectively. The comparison of different parameters indicated that non-genetic factors had a significant impact on milk production. These factors include the region where the survey was conducted, the calving season, the financial context of the farmer, parity or lactation, and first calving age. By analyzing the mean of these parameters, we could determine their impact on milk yield potentials. Given the influence of external variables and differences in the qualities under investigation, the study indicates that significant improvements in the population of Gangatiri cattle can be accomplished by improved management.

Multiple factors shape social contacts in dairy cows

Cattle develop preferential relationships with other individuals in the herd. These social interactions between individuals have a significant impact on both animal welfare and production. Given the relevance of social behaviour in dairy cattle, scientific studies have focused on understanding social interactions among cattle. These may also be influenced by individual area preferences, particularly when animals are housed in confined spaces. Therefore, investigating the relationship between individual area preferences and social interactions is essential for understanding social behaviour in dairy cattle. Real-time location systems provide the opportunity to monitor individual area preferences and social contacts at the same time. This study aims to assess the impact of dairy cows' area preferences on their daily social contacts and to determine the potential implications of overlooking individual area preferences in social behaviour studies. The individual position of the lactating cows was automatically collected once per second for two months on a Swedish commercial farm housing dairy cows inside a free-stall barn. The location data of 243 lactating cows was used to construct the social networks and to estimate the similarity of the area utilisation distributions between these individuals. The effect of utilisation distribution similarity in social networks was investigated by applying separable temporal exponential random graph mixed models. The role of different cow characteristics in the similarity of the utilisation distributions was assessed through a linear mixed model. Our analyses stressed the importance of similarity of area preference, parity, kindergarten effect, and filial relatedness in shaping daily social contacts in dairy cattle. The kindergarten effect refers to the effect on cow behaviour of being grouped together in the early stages of their lives. Similarity of area preference was influenced by the kindergarten effect and relatedness by pedigree, which favoured interactions between these individuals. The described approach allowed to disassociate the area preference from the social contacts between cows, providing more accurate results of the importance of the cow’s characteristics on their social behaviour.

Study of physical and chemical characteristics of cow’s milk evaporated by climbing film evaporator method

Study of physical and chemical characteristics of cow’s milk evaporated by climbing film evaporator method

Physico-chemical characteristics of goat, cow and buffalo milk

The present investigation entitled “Physico-chemical characteristics of goat, cow and buffalo milk” was carried out during March to May 2023 at the Dairy Farm Rajola Livestock Production and Management (Unit), Department of Natural resource management, Faculty of Agriculture, Mahatma Gandhi Chitrakoot Gramodaya Vishwavidyalaya, Chitrakoot – Satna (Madhya Pradesh), to the study physico-chemical qualities of raw milk of goat, cow and buffalo. The results of the investigation regarding the chemical qualities of milk of goat, cow and buffalo have been presented in this chapter with the help of tables and graphs. The study has been divided into the following sub- headings. Protein (%), specific gravity (cc), fat (%), lactose (%), ash (%), total solid (%), water (%) and solid not fat (SNF) (%). In view of the findings and results presented above, it may be concluded that the physico-chemical quality of milk of buffalo was superior to cow and goat milk, due to higher protein. Specific gravity, fat content, lactose, total solid and SNF and lower ash and water content in buffalo milk.

Effectiveness of cooling interventions on heat-stressed dairy cows based on a mechanistic thermoregulatory model

Addressing heat stress in dairy farming is a substantial challenge, and there is an increasing need for efficient cooling systems, even in regions with moderate climates. Accurately predicting the efficacy of diverse cooling options under different climatic conditions is crucial for reducing heat stress in modern high-producing dairy cows, aligning with sustainability goals. This study assessed the effectiveness and feasibility of different cooling measures, including fans, sprinklers with fans, and evaporative air cooling, using a dynamic thermoregulatory model. This 3-node dynamic model was developed based on recent animal data simulating the processes of dairy cows' physiological regulation and heat dissipation under various environmental conditions. The cooling methods were based on two principles: enhancing heat loss from cows using fans with/without sprinklers; lowering the ambient temperature by evaporative air cooling. The predicted results were discussed and partly validated using the experimental data from the literature. The predictions indicated that fan cooling alone was effective in ambient temperatures below 26 °C, while higher temperatures required a combination of fans and sprinklers for effective heat stress alleviation. Consideration of individual cow characteristics and environmental factors, including fan speed and wetting area, is crucial for optimal cooling. In regions with high relative humidity, evaporative air cooling could be counterproductive to some extent. The model's predictions largely aligned with experimental data, demonstrating its capability to forecast cooling effects under various climatic conditions. Future model improvements included refining calculations for water holding capacity, wetted skin area, and dry time, depending on the influence of spraying time and rate.

Effect of oxytocin use during colostrum harvest and the association of cow characteristics with colostrum yield and immunoglobulin G concentration in Holstein dairy cows

Our objectives were to determine the effect of oxytocin use during colostrum harvest on colostrum yield and IgG concentration in Holstein dairy cows on a commercial dairy in New York and to describe associations of cow characteristics with these outcomes. Animals were enrolled between July and October 2023 using a randomized block design, with day of enrollment as the unit of randomization. A median (range) of 10 (3-19) cows were enrolled per day. Treatments were (1) 40 IU oxytocin (OXY40), (2) 20 IU oxytocin (OXY20), and (3) an untreated control group (CNTR). Oxytocin was administered i.m. ∼45 s before unit attachment in a rotary parlor. Colostrum weight was measured using the colostrum bucket-embedded scale or a platform scale when the yield was less than the smallest bucket scale. The concentration of IgG ([IgG]) in colostrum was determined using radial immunodiffusion and used to calculate total IgG, and DM (%) was determined by oven drying. Individual cow characteristics such as parity, calf sex, weight, dystocia score, stillbirth, and milk production in wk 4 of lactation; additionally, for multiparous cows, dry period length and previous lactation dry-off linear SCS were collected. Data were analyzed separately for primiparous and multiparous cows using backward stepwise elimination. To produce final mixed effects ANOVA models, primiparous cows (n = 201) were randomized to 35.8% (n = 72) OXY40, 32.8% (n = 66) OXY20, and 31.3% (n = 63) CNTR. Multiparous groups (n = 435) were randomized to 34.7% (n = 151) OXY40, 29.7% (n = 129) OXY20, and 35.6% (n = 155) CNTR. The median (range) colostrum yield was 6.0 (0-20.6) kg and [IgG] was 98.5 (0.1-293.6) g/L in the study population. In primiparous cows, OXY40 had a higher colostrum yield (LSM [95% CI]) of 5.4 (4.9-5.9) kg compared with both OXY20 (4.1 [3.5-4.7] kg) and CNTR (3.8 [3.3-4.3] kg). In multiparous cows, OXY40, OXY20, and CNTR did not differ in colostrum yield (5.9 [5.3-6.5], 5.7 [5.1-6.3], and 5.4 [4.8-6.0] kg, respectively), but colostrum yield was greater in parity 2 compared with all other parities, cows giving birth to male calves, cows with the highest milk production at wk 4 of lactation, and cows with a dry period of >65 d. Oxytocin use did not affect [IgG] in either primiparous or multiparous cows, but [IgG] was highest in cows in parity ≥4 and lowest in cows dry >65 d. In summary, oxytocin use at 40 IU i.m. was associated with a higher colostrum yield in primiparous cows only and no change in [IgG]. Oxytocin use likely addressed disturbed milk ejection and therefore increased colostrum yield in heifers milked for the first time in a rotary parlor. This study confirms cow characteristics associated with colostrum production within a single herd.

Variation in partial direct costs of dry cow therapy on 37 large dairy herds

The objective of this observational study was to estimate partial direct costs of dry cow antibiotic therapy (DCT) protocols used on 37 large dairy herds in Wisconsin and to estimate the potential monetary savings and reduction in antimicrobial usage (AMU) if selective DCT was used. Partial direct costs of DCT were calculated using costs of intramammary (IMM) antimicrobials and teat sealants. Data were retrospectively collected on 37 large dairy farms for a period of 1 yr and included the total number of cows dried off, types of IMM antimicrobial used, and product prices (obtained from farm invoices). A single farm visit was performed to verify data. Clinical mastitis (CM) and SCC history across lactation were used as the criteria to identify cows eligible to receive only teat sealants (no antibiotic DCT) based on adoption of a hypothetical selective DCT program. Descriptive statistics were performed using PROC MEANS to summarize continuous herd and cow characteristics. Differences in costs among IMM antibiotic products and eligibility to not receive antibiotics at dry-off by parity were analyzed using ANOVA. Differences in milk yield at the last test-day and DIM at dry-off based on eligibility for selective DCT were analyzed using PROC MIXED. A total of 35,691 cows were dried off across all herds (n = 37) and most of the herds used IMM antibiotic DCT at dry-off in most of the cows. Teat sealant was used as part of the dry-off protocol in all but 3 herds. Of the enrolled farms, 30 used blanket antibiotic DCT in all quarters of all cows and 7 herds used selective DCT with no administration of antibiotics given to 0.8% to 58% of the dry cows within the herd. Across all farms, the average cost of products given per dried cow was $19.57 ± 0.64 (mean ± SE) and ranged from $8.72 to $24.04. As expected, the cost per dried cow was greater ($23.45 ± $0.38) in herds that used higher cost IMM antibiotics as compared with herds that used lower cost IMM antibiotics ($16.64 ± $0.40). When using an algorithm based on udder health records to hypothetically select cows that would be eligible to receive teat sealants only (no antibiotic DCT), eligibility ranged from 27.3% to 93.3% within-herds and varied by parity, milk yield at last test-day, and DIM at dry-off. If a selective DCT program based on udder health records was used, an overall reduction of $5.37 (27% of total costs) per dry cow would be expected. Likewise, adoption of selective DCT based on udder health records would reduce AMU at dry-off by approximately 51%. However, neither of these estimates included potential adverse health complications (such as increased CM) that can occur if selective DCT programs are not effectively performed. Variations in partial direct costs at dry-off were observed among herds based on treatment protocols. In herds that have good udder health management and contagious mastitis pathogens controlled, adoption of selective DCT based on SCC and history of CM can reduce AMU and partial direct costs of dry cow management.

A comprehensive integration of factors affecting vitamin B12 concentration in milk of Holstein cows: Genetic variability, milk productivity, animal characteristics, and feeding management

Daily vitamin B12 (VB12) requirements of humans can naturally be fulfilled by animal product consumption, especially products from ruminants because of bacteria dwelling in their rumen. Indeed, only bacteria can synthesize this vitamin. Milk is hence an excellent source of VB12. This cross-sectional study was undertaken to unravel factors, such as genetic variation, diet and cow characteristics, and milk production, explaining the large variation in milk VB12 concentration among cows by using an integrative approach. Milk samples from 2 consecutive milkings were collected from 3,533 Canadian Holstein cows (1,239 first, 932 second, and 1,362 third and more lactations) located in 99 herds with various feeding management. For the purpose of genetic variation analysis, pedigrees were traced back for 3 complete generations for each sire and dam. A total of 10,021 identities were used in the subsequent genetic analyses. Milk VB12 averaged 4.2 ng/mL with a range between 0.7 and 9.0 ng/mL. Dietary fiber (NDF from forage, dietary NDF, ADF, and lignin) increased and dietary components related to energy (NFC, starch, NEL, and percentage of concentrate) decreased VB12 in milk. Milk VB12 varied with DIM, with a similar pattern as milk fat and protein concentration lactation curves. Milk VB12 increased as age at calving increased. When disregarding the herd variance, the heritability value was 0.37, meaning that milk VB12 can be modified by genetic selection. The final model including factors related to the diet, animal characteristics and milk productivity, and genetic variation explained 79% (pseudo-R2) of the milk VB12 variation. When excluding the random effect of the cow (i.e., excluding the animal and genetic relationships), the pseudo-R2 dropped to 43%, reinforcing the importance of genetic variation in explaining milk VB12 variation. To our knowledge, the present study is the most comprehensive evaluation of factors affecting milk VB12 variation including the greatest number of cows from various lactation stages.

Identification of some genetic markers as productive and reproductive traits in Ukrainian dairy cattle breeding

A Selection based on DNA markers is a breeding technique grounded in the genomic selection value of animals. The aim of the research is to study the genotypic profile of cows of different breeds in Ukrainian breeding in relation to the genes LEP, CSN3, TG5, BLG, and Pit-1 and to identify the probability of using them as markers for reproductive traits in cows. During the study, the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method was used to analyze the genes and determine their polymorphic characteristics. The obtained data indicated that the same gene variants have varying effects in the studied breeds due to their diverse influences on the genomic background. Specifically, the homozygous state of leptin genes (LEPCC) and pituitary-specific transcription factor (PIT-1BB) was observed to impact the reproductive characteristics of cows in the evaluated breeds. Meanwhile, for the genes casein (CSN3AB), thyroglobulin (TG5CT), and beta-lactoglobulin (BLGAВ), the heterozygous state of alleles was found to influence the key reproductive traits of dairy cattle of Holstein origin. The polymorphism of the genes CSN3, βLG, TG, PIT-1, and LEP indicated the presence of genetic potential for the reproductive function of cows and can be utilized as molecular markers in selective breeding, providing significant progress in improving not only the traits of dairy cattle productivity but also reproductive function. Therefore, in the implementation of selective breeding work, it is advisable to consider genotyping for the genes CSN3, βLG, TG, PIT-1, and LEP as an additional criterion for the selection of animals to enhance both their milk and reproductive characteristics.

Effect of Steam Pressure Toasting Duration on Snowbird Faba Bean Seeds and the Impact on the Intestinal and Metabolic Characteristics in Dairy Cows

The response of feedstuffs to thermal processing depends on the type of feed and the thermal processing methods being applied. Steam pressure toasting (SPT) has been used to modify the nutrient degradability and enhance the nutritional quality of pulses, including faba bean seeds (FBS). Strategic feeding approaches are essential for balancing diets and maintaining adequate nutrition, especially in high-performing ruminants. This research aimed to determine the effects of SPT duration in FBS on the intestinal and metabolic characteristics of dairy cows. Faba Bean seeds (three harvesting years) were processed at 121 °C for 0, 30, 60, 90, and 120 min. Rumen degradation and intestinal digestion were determined using the in situ and modified in vitro three-step techniques. The true protein supplied to the small intestine was also determined using the NRC and DVE systems. Our results showed a reduced total digested DM (TDDM) with longer SPT duration (quadratic, p = 0.02). The intestinally digested crude protein (IADP) increased from 62 to 220 g/kg DM with 0 to 120 min of SPT, respectively (p < 0.01), whereas the total tract digestible starch (TDSt) gradually decreased from 321 to 182 g/kg DM based on SPT time (p < 0.01). On the other hand, the truly digested protein in the small intestine (DVE) and the total metabolizable protein (MP) increased from 138 to 282 g/kg DM and 129 to 282 g/kg DM, respectively, with 0 to 120 min of SPT (quadratic, p < 0.01). The Feed Milk Value (FMV), based on both the DVE/OEB and NRC dairy nutrition systems, also increased with SPT (Quadratic, p < 0.01). The processing of FBS with SPT at 121 °C effectively reduced the highly degradable protein fraction in the rumen, shifting to a higher rumen undegraded protein (RUP) which was able to reach the small intestine. In the current study, the total MP, DVE, and FMV in dairy cows showed an overall increase with SPT in FBS.

Quality assessment of chemical and microbiological characteristics of cow’s milk and some dairy products in the New Valley governorate

Quality assessment of chemical and microbiological characteristics of cow’s milk and some dairy products in the New Valley governorate

Comparative Analysis of Milking and Behavior Characteristics of Multiparous and Primiparous Cows in Robotic Systems.

Robotic milking systems are successful innovations in the development of dairy cattle. The objective of this study was to analyse the milking characteristics and behavior of dairy cows of different calving orders in "milk first" robotic milking systems. The data were collected from a commercial herd located in the Midwest region of Minas Gerais (Brazil), which uses an automatic milking system (AMS TM, DeLaval). Were analysed 26,574 observations of 235 Holstein cows were available. Data were evaluated by multivariate analysis of variance and the Tukey test. - Tthe characteristics milk flow and milking efficiency were more favourable for multiparous cows (p <0.01), while the time in the stall was more favourable for primiparous females (p <0.01). The values of handling time were better in the primiparous cows (p <0.01). Primiparous cows had higher amounts of kick-off (p <0.001), and multiparous cows had higher incomplete milkings (p <0.001). The number of incomplete milkings showed a higher ratio in terms of reduction in milk production in 26.6% in primiparous cows and 26.7% in multiparous cows (p <0.01). Regarding the behavioral characteristics, primiparous cows had higher amounts of kickbacks, while multiparous cows had greater quantities of incomplete milkings.