Brown Swiss Cows Research Articles

Parameters of blood metabolites from Brown Swiss cows in production in the Puno Region. An evaluation according to the number of births

Parameters of blood metabolites from Brown Swiss cows in production in the Puno Region. An evaluation according to the number of births

Effects of Two Types of Estrogen on the Follicular Wave for in Vivo Oocyte Collection in Brown Swiss Cows

The manipulation of follicular waves through hormonal treatments, such as estrogen administration, plays a crucial role in optimizing in-vivo oocyte collection for assisted reproductive technologies. The present study aimed to evaluate the effect of two specific types of estrogen on follicular wave dynamics and their impact on in-vivo oocyte collection in Brown Swiss cows. Fourteen cows, in their first lactation, weighing approximately 340 kg were randomly assigned to one of two treatments including T1 (estradiol cypionate) and T2 (estradiol benzoate). Both treatments were administered at 1.2 mg of estrogen, at day 0 of the experiment. All Brown Swiss cows were provided with a diet entirely consisting of alfalfa grazing. On day 7, follicular wave dynamics were assessed using a DP-50 vet ultrasound device equipped with a 7.5 MHz transducer for transvaginal follicular aspiration guidance. Follicle counts were categorized into three size ranges including 2-4 mm (small), 4-8 mm (medium), and greater than 8 mm (large). Additionally, the quantity and quality (viable oocytes) of the collected oocytes were evaluated by the Ovum Pick Up (OPU) team for oocyte viability on day 7. The study assessed the follicular dynamics (number of follicles) and efficiency of oocyte collection (viable oocytes) in cows treated with Estradiol Cypionate (T1) and Estradiol Benzoate (T2). The average number of small, medium-sized, and large follicles size were 6.048 ± 6.037, 3.16 ± 2.01, and 0.53 ± 0.67 respectively. The total number of follicles was 9.59 ± 3.56. The mean number of viable oocytes recovered was 3.024 ± 1.66, while the mean number of non-viable oocytes was 1.47 ± 1.01. The results indicated no significant differences between treatments in the size of small, medium, and large follicles, nor in the total number of follicles and viable oocytes recovered. However, a significant difference was observed in the number of non-viable oocytes recovered, with a higher mean in T2 (1.86) compared to T1 (1.09). The results indicated an adequate follicular response and viable oocyte recovery in both treatment groups (estradiol cypionate and estradiol benzoate). However, variations in oocyte viability were observed, with estradiol cypionate showing a slight advantage.

225 Kidney function and nitrogen excretion in Brown Swiss and Holstein dairy cows

Abstract The agricultural sector contributes to nitrogen (N) emissions since farm animals excrete considerable N amounts via feces and urine. To reduce N emissions by dairy cattle, methods predicting accurately individual N emissions are of great interest. Recent data showed that Brown Swiss (BS) cows have greater urea concentrations in milk and blood than Holstein (HO) cows. However, it is still unknown if greater BUN concentrations in a particular breed are congruently reflected by concomitantly increased contents of nitrogenous compounds in other media (e.g., urine and saliva). Thus, the present study simultaneously assessed biomarkers for kidney function like urea, and creatinine and symmetric dimethylarginine (SDMA) concentrations in several body fluids (i.e., blood, urine, milk, and saliva) as well as nitrogen excretion in feces in BS and HO cows under identical feeding conditions. Blood, saliva, urine, and feces were sampled in 31 multiparous BS and 46 HO cows kept under identical feeding and management conditions. Samples were collected at different lactational stages after the monthly DHIA control test-day. Concentrations of urea and creatinine were measured in serum, urine, and saliva. Symmetric dimethylarginine was determined in serum, which is an established indicator for glomerular filtration rate (GFR). Feces were analyzed for dry matter content and nitrogen concentrations. Data on milk urea and protein concentrations, and daily milk yield were obtained from the monthly DHIA test-day records. The effects of breed, time, and parity number on blood, saliva, urine, feces, and milk parameters were evaluated with the GLM procedure with breed, time, and parity number as fixed effects. Differences between BS and HO were assessed by the Tukey-corrected t-test at P < 0.05. Dry matter intake and body weight were similar in BS and HO cows (P > 0.05). No differences between BS and HO were observed for milk yield, fecal DM and nitrogen content. BS cows showed greater urea concentration (25.8 ± 0.7 vs 21.8 ± 0.7 mg/dL), and protein content in milk (3.70 ± 0.08 vs 3.45 ± 0.07%) than HO cows (P < 0.01). Concentrations of urea, creatinine, and SDMA in serum, were greater in BS than in HO cows (P < 0.01) with 5.46 ± 0.19 vs 4.72 ± 0.13 mmol/L for urea, 105.96 ± 2.23 vs 93.07 ± 1.50 mmol/l creatinine, and 16.78 ± 0.69 vs 13.39 ± 0.44 µg/dL SDMA, respectively. Urea and creatinine concentrations in urine and saliva did not differ among breeds. Despite greater urea and creatinine concentrations in blood, and milk urea content in BS compared with HO, excretion of these parameters did not differ between breeds in urine. Our results suggest a reduced renal glomerular filtration rate in BS compared with HO. The underlying mechanisms require further investigations.

Benchmarking claw health across three dairy cow breeds in 508 dairy farms using numerical claw health indicators

Currently, prevalence and incidence of claw lesions are used as parameters for benchmarking claw health. The aims of this study were to create a benchmarking system for claw health utilizing the claw health indicators Farm-Claw-Score (FCS) for the herd and Cow-Claw-Score (CCS) for the individual animal, and to benchmark claw health of the three predominant dairy cattle breeds in Austria. Claw health data from 17,642 cows from 508 Austrian dairy farms were analyzed. The CCS and FCS were calculated based on recorded claw lesions and their three severity levels using geometrically weighted scoring. The FCS of each of the dairy farms was classified into five percentile thresholds (P10, P25, P50, P75, P90), with the FCS calculated using the median value of CCS in each herd. Furthermore, claw health was benchmarked for three breeds (Fleckvieh, Holstein, Brown Swiss cows), using claw lesion prevalences and CCS values.When the median FCS was calculated, dairy farms in P50 and below had an FCS of 20.0, indicating very good claw health. However, P90 farms showed an FCS-MEDIAN of 67.5. Evaluation of the prevalences of the 14 claw lesions considered and the CCS values revealed that Fleckvieh cows (CCS-MEDIAN: 24.0), followed closely by Holstein cows (CCS-MEDIAN: 22.7) had significantly poorer claw health (P < 0.0001) compared to Brown Swiss cows (CCS-MEDIAN: 12.0). The use of CCS and FCS as primary claw health indicators allowed for a quick assessment of the current state of an individual cow and a dairy herd in a benchmarking system. Detailed information on the claw health of each animal and the dairy herd can be easily reviewed by examining diagnosis lists that display prevalences, particularly those related to lameness, in the respective electronic documentation systems.

Biochemical and morphological blood parameters and the level of natural resistance of imported cows in Armenia

The article presents the results of a comparative study morphological and biochemical features of blood and indicators natural resistance of imported Holstein cows, Simmental and brown Swiss cows, in the conditions of the farm LLC “Agroholding Armenia” near the city of Spitak, mountainous area of the Republic Armenia. For the purpose of conducting the experiment, 3 groups of animals were formed I – Holstein, II – Simmental and III – brown Swiss, 15 heads each one. The groups were compiled using the method of analog groups. Conditions the contents and feeding were the same and in accordance with the accepted According to the technology, the cows had an average fatness. The results of our research have been confirmed, what are the fluctuations morphological and biochemical parameters of the blood of the bred farms of imported breeds have minor difference from existing physiological norms, but according to the content of cow globulin groups II and III were inferior to the norm, which may be due to pedigree features in the existing conditions of feeding and maintenance. Hematological date and indicators of natural resistance they testify to the best adaptive qualities and adaptive the possibilities of imported animals.

Factors influencing pregnancy loss between days 30 and 70 in a single cattle herd: A comprehensive analysis of sire, cow, and other contributing factors

This retrospective study utilized a mixed-effects logistic model analysis to investigate variables associated with the probability of pregnancy loss (PL) between days 30 and 70 in a dataset comprising 9507 pregnancies from a single cattle herd over 10 years. The model incorporated fixed-effect variables including cow breed (Holstein, Crossbred, and Brown Swiss), parity (1st, 2nd, 3rd, and 4th or more), insemination seasons, insemination number (≤3 vs >3), estrus nature (spontaneous vs synchronized), postpartum problems, sire breed (Holstein, Fleckvieh, Brown Swiss, and Montbéliarde), zygote genotypic (pure vs crossbred), days in milk (DIM) at insemination, actual 305-day milk yield, and sire conception rate. Additionally, random effects included sire (n = 129), cow (n = 3463), and production years (n = 10). The results revealed that cows inseminated with Brown Swiss sires or sires with lower initial conception rates had higher PL rates. Biparous cows, cows with lower 305-day milk yield, cows inseminated later in DIM, cows receiving the 4th or subsequent insemination, and cows inseminated during winter or autumn had lower PL rates. The estrus type and zygote genotype did not significantly impact PL. The random effects of cow, sire, and production years were estimated at 0.230, 0.054, and 0.112, respectively. In conclusion, the study findings suggested that improving management practices for high-yielding cows, cows in early lactation stages, and cows exposed to thermal stress conditions, along with utilizing Brown Swiss cows and sires with high initial conception rates per insemination, could potentially decrease overall PL rates on the farm. Nonetheless, the results did not support the use of Crossbred cows, sires from different breeds, or specific sires to mitigate PL rates on the farm.

Factors effecting the lactation curve parameters of Brown Swiss and Jersey cows in Türkiye

Factors effecting the lactation curve parameters of Brown Swiss and Jersey cows in Türkiye

Milk productivity of brown swiss cows of different genotypes

Milk productivity of brown swiss cows of different genotypes

Kidney function, but not nitrogen excretion, differs between Brown Swiss and Holstein dairy cows

Brown Swiss (BS) cows have greater urea concentrations in milk and blood compared with Holstein (HO) cows. We tested the hypothesis that BS and HO cows differ in kidney function and nitrogen excretion. Blood, saliva, urine, and feces were sampled in 31 multiparous BS and 46 HO cows kept under identical feeding and management conditions. Samples were collected at different lactational stages after the monthly DHIA control test-day. To test the glomerular filtration rate (GFR) and urea excretion, concentrations of creatinine and urea were measured in serum, urine, and saliva. As an additional marker to estimate GFR, we determined symmetric dimethylarginine (SDMA) in serum. Feces were analyzed for dry matter content and nitrogen concentration. Data on milk urea and protein concentrations, and daily milk yield were obtained from the monthly DHIA test-day records. The effects of breed, time, and parity number on blood, saliva, urine, feces, and milk parameters were evaluated with the GLM procedure with breed, time, and parity number as fixed effects. Differences between BS and HO were assessed by the Tukey-corrected t-test at P < 0.05. Concentrations of urea, creatinine, and SDMA in serum, were greater in BS than in HO cows (P < 0.01): 5.46 ± 0.19 vs 4.72 ± 0.13 mmol/L (urea), 105.96 ± 2.23 vs 93.07 ± 1.50 mmol/l (creatinine), and 16.78 ± 0.69 vs 13.39 ± 0.44 µg/dL (SDMA). We observed a greater urea concentration in BS cows (25.8 ± 0.7 vs 21.8 ± 0.7 mg/dL) and protein content in milk (3.70 ± 0.08 vs 3.45 ± 0.07%) than in HO cows (P < 0.01). Urea and creatinine concentrations in urine and saliva did not differ among breeds. No differences between BS and HO were observed for milk yield, fecal DM, and fecal nitrogen content. Dry matter intake and body weight were similar in BS and HO cows (P > 0.05). Despite greater urea, creatinine, and SDMA concentrations in blood as well as a higher milk urea content in BS compared with HO, respective concentrations in urine did not differ between breeds. In conclusion, our results demonstrate a lower renal GFR in BS compared with HO cows, thereby contributing to the greater plasma urea concentration in BS cows. However, estimation of nitrogen excretion via milk, urine, and feces does not entirely reflect nitrogen turnover within the animal.

Heat stress has divergent effects on the milk microbiota of Holstein and Brown Swiss cows.

Heat stress (HS) is one of the pivotal causes of economic losses in dairy industries and affects welfare and performance, but its effect on milk microbiota remains elusive. It is also unclear if and how different breeds may cope with HS in sustaining productive performance. The objectives of this study were to compare a) the performance of 2 dairy breeds, namely Holstein and Brown Swiss, subjected to HS and b) the different effects of HS on the milk microbiota of the 2 breeds in thermal comfort conditions and HS. The study was carried out on 36 dairy cows, 18 per breed. The HS was induced by switching off the cooling system during a natural heat wave for 4 d. Besides the Temperature Humidity Index (THI), the animal stress was confirmed by measuring respiratory frequency and rectal temperature twice daily at 4 a.m. and 3 p.m. The HS differently impacted the 2 breeds. Rectal temperatures were higher in Holstein cows, while no changes in rectal temperature were found in Brown Swiss. Milk yield recording and sampling were performed during the morning milking of d 1 (at 4.00 a.m.) and afternoon milking of d 4 (at 5.00 p.m.). Productive parameters were also different: milk yield, fat-corrected milk, energy-corrected milk, protein and casein content, and renneting parameters were decreased in Holstein but remained unaffected in Brown Swiss. The HS also modified the milk microbiota of the 2 breeds differently. During HS, the Brown Swiss milk microbiota was richer (α diversity) than the Holstein one. Comparing the time points before and during HS within breeds showed that Brown Swiss milk microbiota was less affected by HS than Holstein's. Under the same thermal comfort condition, milk microbiota did not discriminate between Brown Swiss and Holstein. Consistently with α and β diversity, the number of operational taxonomic units (OTUs) at the genus level that changed their abundance during HS was higher in Holstein (74 OTUs) than in Brown Swiss (only 20 OTUs). The most significant changes in abundance affected Acinetobacter, Chryseobacterium, Cutibacterium, Enterococcus, Lactococcus, Prevotella-9, Serratia, and Streptococcus. In conclusion, the present report confirms and extends previous studies by demonstrating that Brown Swiss cows regulate their body temperature better than the Holstein breed. The relative thermal tolerance to HS compared with Holstein is also confirmed by changes in milk uncultured microbiota, which were more evident in Holstein than in Brown Swiss.

The A1/A2 β-casein genotype of cows, but not their horn status, influences peptide generation during simulated digestion of milk

The effect of the horn status of cows on their milk composition and quality is a controversial research topic. In this study, 128 milk samples from 64 horned and 64 disbudded Brown Swiss and Original Braunvieh cows were collected from alpine farms where both horned and disbudded cows were grazing on mountain pastures. The samples were analyzed for their detailed composition and protein digestion in a simulated in vitro digestion (INFOGEST). To exclude probable influences on digestion, the β-CN genotype with its variants A1 and A2 was also included in the study. The effects of horn status and β-CN genotype were investigated in linear mixed models, which included additional influencing random factors such as Original Braunvieh blood proportion, stage of lactation, and farm. Horn status did not have any effect on milk composition or digestion. In contrast, milk from A1A1 cows showed a different protein digestion than milk of A1A2 and A2A2 cows in the gastric phase, including smaller amounts of β-casomorphin(BCM)21-associated peptides and larger amounts of BCM11-associated peptides. Abundances of BCM7 did not differ between β-CN genotypes. At the end of the intestinal phase, the digested milk of A1A1 and A2A2 β-CN genotypes did not differ.

Association of three single nucleotide polymorphisms in the LPIN1 gene with milk production traits in cows of the Yaroslavl breed.

Lipin-1 is a member of the evolutionarily conserved family of proteins and is expressed predominantly in adipose tissue and skeletal muscle. On the one hand, lipin-1 is an enzyme that catalyzes the dephosphorylation of phosphatidic acid to diacylglycerol (DAG) and thus participates in the metabolic pathways of biosynthesis of storage lipids in the cell, membrane phospholipids, and intracellular signaling molecules. On the other hand, lipin-1 is able to be transported from the cytoplasm to the nucleus and is a coactivator of lipid metabolism gene transcription. It was shown, using the analysis of single nucleotide polymorphism (SNP) associations, that the lipin-1 coding gene (LPIN1) is a promising candidate gene for milk production traits in Holstein and Brown Swiss cows. However, it is unclear how much of its effect depends on the breed. The Yaroslavl dairy cattle breed was created in the 18-19 centuries in Russia by breeding northern Great Russian cattle, which were short and poor productive, but well adapted to local climatic conditions and bad food base. It was shown by whole genome genotyping and sequencing that the Yaroslavl breed has unique genetics compared to Russian and other cattle breeds. The aim of the study was to assess the frequency of alleles and genotypes of three SNPs in the LPIN1 gene and to study the association of these SNPs with milk production traits in Yaroslavl cows. Blood samples from 142 cows of the Yaroslavl breed were obtained from two farms in the Yaroslavl region. Genotyping of SNPs was carried out by polymerase chain reaction-restriction fragment length polymorphism method. Associations of SNPs with 305-day milk yield, fat yield, fat percentages, protein yield, and protein percentages were studied from the first to the fourth lactation. Statistical tests were carried out using a mixed linear model, taking into account the relationship between individuals. We identified three SNPs - rs110871255, rs207681322 and rs109039955 with a frequency of a rare allele of 0.042-0.261 in Yaroslavl cows. SNP rs110871255 was associated with fat yield during the third and fourth lactations. SNP rs207681322 was associated with milk yield for the second, third and fourth lactations, as well as protein yield for the third lactation. Thus, we identified significant associations of SNPs rs207681322 and rs110871255 in the LPIN1 gene with a number of milk production traits during several lactations in Yaroslavl cows.

The first results of the use of the gene pool of the Kalmyk breed on the brown stock of Brown Swiss cattle

The given investigation is devoted to a comparative assessment of the growth, meat productivity and efficiency of beef production by bulls of different genotypes. It was formed 3 groups of bull calves, 15 heads in eachon the 2nd-3rd days after birth: group firstis brown Swiss calves, the second is Kalmyk breed, the third is crossbreeds obtained from crossing Brown Swiss cows and Kalmyk bulls. It has been established that to the age of 18 months, the advantage of Kalmyk bulls and their crossbreeds in terms of live weight over purebred animals of the Brown Swiss breed averaged 16.3-28.2 kg (P&gt;0.999). According to the average daily increase in live weight for the entire production cycle, animals of the Kalmyk breed favorably differed among the analyzed genotypes of young animals, the superiority of which over their peers of different origin varied within 29-61 g (P&gt; 0.999). The difference between bulls of the Brown Swiss breed and crossbreds was 32 g (P&gt;0.999) in favor of the latter. From bull-calves of the Kalmyk breed and their crosses, in contrast to those of the Brown Swiss breed, heavier carcasses were obtained - by 24.8 (P&gt; 0.99) and 14.9 (P&gt; 0.99) kg, slaughter yield is by 2.4 (P&gt;0.99) and 1.4 abs.%, respectively. Representatives of the Kalmyk breed and crossbred peers differed in the highest yield of pulp, whose superiority over bulls of the improved breed was 12.0 (P&gt;0.99) and 7.5 (P&gt;0.99) kg, respectively. A higher level of profitability at the level of 34.6-37.9% was characterized by the descendants of bulls of the Kalmyk breed versus 26.7% in the group of brown Swiss breed.

PRODUCTIVE RESPONSE OF LACTATING DUAL-PURPOSE COWS GRAZING IN AN AGROSILVOPASTORAL SYSTEM DURING THE DRY SEASON SUPPLEMENTED WITH LOW LEVELS OF CRUDE PROTEIN

&lt;p&gt;&lt;strong&gt;Background. &lt;/strong&gt;Cattle production in tropical regions of Mexico is in dual-purpose farms (DP) on unintended agrosilvopastoral systems (ASPS) with pastures dominated by tropical grasses with scattered shrubs and trees. During the dry season due to the forage diminished nutritional value and availability most farmers supplement their cattle to sustain milk production and weight gains of calves, without taking into consideration the wide variety of forages available in grazing lands to decide the composition of supplements offered to their cattle. &lt;strong&gt;Objective/hypothesis. &lt;/strong&gt;The objective of the study was to determine the effect of low levels of crude protein (CP) content in supplements (S10 = 100, S11 = 110 and S12 = 120 g CP/kg of DM) on the performance of lactating Brown Swiss (BS) cows on an ASPS during the dry season. We hypothesize that low levels of CP in supplements of lactating grazing cows on an agrosilvopastoral system during the dry season would not affect animal performance. &lt;strong&gt;Methodology. &lt;/strong&gt;The study was carried out in the dry season (March to June of 2012), in a commercial DP in the State of Mexico. Eighteen multiparous BS cows and their calves were used in the study, randomly allocated to three groups (six cows/group), to receive one of three supplements (4.5 kg DM/cow/day), consisting of 100, 110 or 120 g/kg DM of crude protein (CP) S10, S11 and S12, respectively. Data were analysed as a complete random experimental design with a mixed model. &lt;strong&gt;Results. &lt;/strong&gt;There were no significant differences in most of the animal performance variables (P &amp;gt; 0.05), except for fat protein corrected milk (FPCM) where S12 (6.4) was significantly higher than S10 and S11 (4.7 and 4.5 kg/day, respectively). Milk protein yields (kg/day) significantly increased as the CP level increased in supplements. High levels of milk urea nitrogen (MUN) were detected (mean 14.0 mg/dL). &lt;strong&gt;Implications. &lt;/strong&gt;In similar DP farms where cattle have access to other sources of forages like shrubs and trees, it is possible to reduce the CP content of supplements and to increase the efficiency of utilization of those alternative forages as well as a reduction in supplementation costs. &lt;strong&gt;Conclusion. &lt;/strong&gt;There were no significant differences in the performance of BS cows grazing on an ASPS during the dry season receiving supplements with low crude protein levels. When correcting to fat-protein milk yields a significant difference was found in favour of supplement with 120 g CP/kg of DM.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;

Genetic parameters for lifetime productivity in Holstein and Brown Swiss dairy cows in Honduras

Objective. To estimate the heritability (h2) of age at first parturition (AFP), longevity (L), useful life (UL), and productivity (P), as well as the genetic (rg) and phenotypic correlations between those traits in Brown Swiss and Holstein cows in Northwestern Honduras. Materials and methods. Cattle were raised under tropical conditions and intensive management. The model for AFP assessed the effect of contemporary group (herd, year and birth season combination) as fixed. The model used for L, UL and P included the contemporary group, age group at first calving and their interaction. Data were analyzed using restricted maximum likelihood procedure, adjusted to a univariate and to a bivariate animal model. Results. The h2 estimated for AFP, L, UL and P were 0.16, 0.18, 0.25 and 0.09, respectively, in Brown Swiss cows, and 0.53, 0.49, 0.7 and 0.22, respectively in Holstein. Negative but favorable rg among Brown Swiss cow traits ranged from 0.31 to 0.46 between AFP and the other traits. However, for Holsteins cows, positive rg among AFP and the other traits here studied varied from 0.49 to 0.96. In both cattle breeds, rg among L, UL and P, traits were positive. Conclusions. For all traits evaluated low to medium heritability’s for BS suggest that a slow genetic improvement could be achieved if independent selection of traits is applied, and better response could be expected for H breed. For both breeds the positive rg among L, UL and P suggest thar similar selection criteria could be used.

Case study of the market situation of calves from Alpine dairy farms and the effect of dams’ grazing during the last three months of gestation on auction parameters

The main aim of the study was to assess the recent evolution of cattle breeding in Alpine areas based on the number, quality and price of calves sold at local auctions in the South Tyrol region over the last decade, as case study. In addition, the effect of grazing during dam’s late gestation on calves’ auction quality was investigated to assess whether the inclusion of pasture in Alpine production system has an impact on auction parameters of calves beside its well-known positive effects on cattle welfare and the environment. Similarly, to other geographical areas, the study revealed that the numbers of crossbred calves (especially from specialised dairy breeds) has increased over the last years also in the Alpine area, because of more targeted breeding plans with an intensive use of beef bulls’ semen. Further, purebred calves from dual-purpose breeds (Simmental, Alpine Grey, Pinzgauer) received a higher remuneration in terms of price and market value at auction than purebred calves from specialised Holstein Friesian and Brown Swiss cows. A part of these animals could be available to support an innovative alpine meat supply chain which, if grass-fed, could further strengthen the current landscape maintenance service provided by the mountain livestock husbandry. Dams grazing during the last 90 days of gestation had a limited negative effect on calves’ liveweight and quality traits at auctions. All these results provide useful technical insights to support the switch from dairy to suckler herd system as future productive alternative for some small-scale mountain cattle farms whose viability is essential for the provision of several ecosystem services in the fragile Alpine environment.

The autumn low milk yield syndrome in Brown Swiss cows in continental climates: hypotheses and facts.

Extensive research has been conducted globally on the impact of heat stress (HS) on animal health and milk production in dairy cows. In this article, we examine the possible reasons for the decrease in milk production in Brown Swiss (BS) cows during the autumn season, known as the autumn low milk yield syndrome (ALMYS). This condition has been extensively studied in high-yielding Holstein Friesian (HF) cattle and has also been observed in BS cows with a daily milk yield of around 30kg. Our hypothesis is that the drop in milk yield and the increased prevalence of mastitis in autumn, as found in our recent studies, may be a long-term consequence of summer HS. We re-evaluate our previous findings in light of the possible manifestation of an HS-related form of ALMYS in BS cows. As milk yield, mastitis spread, and reproductive function of cows are interrelated and have seasonal dependence, we examine the consistency of our hypothesis with existing data. The significant drop in milk yield in BS cows in autumn (by 2.0-3.2kg), as well as the threshold of milk yield decrease (temperature-humidity index of 70.7), may point in favour of the manifestation of ALMYS in BS cows, similar to HF cows. Only the percentage effect of seasonal factor (59.4%; p < 0.05) on milk yield of BS cows was significant. HS-related ALMYS provides a robust conceptual framework for diverse sets of productive and animal health data in BS cows, similar to observations in high-yielding HF cattle. However, the limitations associated with the lack of additional data (e.g. immunological indicators) suggest the need for further research to confirm ALMYS in BS breed.

Influence of dietary fiber content and horn status on thermoregulatory responses of Brown Swiss dairy cows under thermoneutral and short-term heat stress conditions

In the present experiment, 10 horned and 10 disbudded mid-lactating Brown Swiss cows were included in a crossover feeding trial with a hay or hay and concentrate diet. The effects of dietary neutral detergent fiber (NDF) content and horn status on thermoregulatory responses under thermoneutral and short-term heat stress conditions were studied, as both are considered to ease the cow's thermoregulation under an environmental heat load. Cows received either ad libitum hay and alfalfa pellets (85:15, C-, NDF content: 41.0%) or restricted amounts of hay and concentrate (70:30, C+, NDF content: 34.5%). The level of restriction applied with the C+ diet was determined from pre-experimental ad libitum intakes, ensuring that both diets provided the same intake of net energy for lactation (NEL). For data collection, cows were housed in respiration chambers for 5 d. The climatic conditions were 10°C and 60% relative humidity (RH), considered thermoneutral (TN) conditions (temperature-humidity index (THI): 52) for d 1 and 2, and 25°C and 70% RH, considered heat stress (HS) conditions (THI: 74), for d 4 and 5. On d 3, the temperature and RH were increased gradually. Compared with TN, HS conditions increased the water intake, skin temperature, respiration and heart rates, and endogenous heat production. They did not affect body temperature, feed intake, or milk production. Lowering dietary fiber content via concentrate supplementation lowered methane and increased carbon dioxide production. It did not mitigate physiological responses to HS. Although the responses of horned and disbudded cows were generally similar, the slower respiration rates of horned cows under HS conditions indicate a possible, albeit minor, role of the horn in thermoregulation. In conclusion, future investigations on nutritional strategies must be conducted to mitigate mild heat stress.

PRODUCTIVE AND ECONOMIC PERFORMANCE OF BROWN SWISS COWS AT DIFFERENT STAGES OF LACTATION FED TWO CRUDE PROTEIN LEVELS

&lt;p&gt;&lt;strong&gt;Background. &lt;/strong&gt;Dairy cows convert between 24 to 32% of dietary nitrogen (N&lt;sub&gt;2&lt;/sub&gt;) into milk protein, the rest of the dietary N&lt;sub&gt;2&lt;/sub&gt; is excreted in urine and feces which contributes to environmental N&lt;sub&gt;2&lt;/sub&gt; pollution. Besides the N&lt;sub&gt;2&lt;/sub&gt; excretions, crude protein (CP) represents up to 69% of the diet´s total cost. Therefore, the best way to reduce environmental pollution and increase dairy profits is the reduction of crude protein in the diet of cows. &lt;strong&gt;Objective. &lt;/strong&gt;To determine the productive and economic performance of Brown Swiss cows at different stages of lactation fed two crude protein levels 14 vs 16%. &lt;strong&gt;Methodology. &lt;/strong&gt;Twenty-three multiparous Brown Swiss cows stratified by stage of lactation as early (EL), mid (ML), and late (LL) were used and subjected to two CP levels 14 and 16% on a crossover design with two experimental periods (EP) of three weeks each. Cows on experimental CP 14% in the EP1 switched to 16% in the EP-2, whereas cows that received a 16% diet in the first EP switched to 14% in the EP2. Milk-to-feed price ratio and income over-feeding cost were estimated as indicators of profitability. &lt;strong&gt;Results. &lt;/strong&gt;The were no significant differences in any response variable due to dietary crude protein (P &amp;gt; 0.05), except for milk protein yield (kg/day) (P = 0.03), where 16% CP had higher yields (0.57) than 14% CP (0.55, kg/day). Cows in early and mid-lactation stages had higher performance than in late lactation (P &amp;lt; 0.05), on most of the response variables. Income over feeding-costs were 0.24 and 0.21 ($ USD/kg) for CP 14 and 16%, respectively. Total income over feeding cost per treatment was $1,020 for CP 14%, and $917 for CP 16%. &lt;strong&gt;Implications.&lt;/strong&gt; The reduction of crude protein in the diet of lactating cows will allow reductions if milk production cost, as well as reductions of N&lt;sub&gt;2&lt;/sub&gt; excretions to the environment. &lt;strong&gt;Conclusions. &lt;/strong&gt;The productive performance of the cows was not affected by a reduction of crude protein in the diet, but the reduction of crude protein resulted in lower milk production cost and higher income-over feeding cost.&lt;/p&gt;

Families of Brown Swiss cows in breeding farms of the Smolensk region

Increasing the dairy productivity of cows is the main goal of breeding work in dairy cattle breeding. The main method of purebred cattle breeding is considered to be breeding by lines and families. In the herds of five padigree farms of the Smolensk region for the breeding of the Brown Swiss breed of cattle 160 main families with a total number of 2285 cows have been established. The number of families on farms ranged from 17 to 40 with the number of animals from 235 to 502, in each. The main indicators of dairy productivity of cows in individual families are determined, the most promising for further breeding work are identified. The best families were formed in the breeding reproducer of the SPC "Druzhba" with record indicators of dairy productivity of cows for the breed. So in the Nevesta's family 917 cows were received: Zlata 2259 (3 – 305 – 8953 -3.94% – 3.31%); Dona 313 (2 – 305 – 11184 – 3.76% – 3.64 %). The Index of genetic similarity between animals of individual families calculated using immunogenetic markers revealed significant differences in the hereditary characteristics of the compared groups.