Breed and season influence on milk quality parameters and in mastitis occurrence

The aims of the present study were to evaluate the performance of Jersey and Holstein cows under different rainfall conditions (dry and rainy seasons) by monitoring aspects related to subclinical mastitis (somatic cell count, microbiological isolation, type of isolated pathogen), milk quality (lactose, protein, fat, total solids) and production (mean milk production) of both breeds. The study was carried out in a dairy farm located in the state of São Paulo, Brazil. Eight visitations were done to the farm, four in a period of high rainfall and four in a period of low rainfall. Milk samples were collected from 79 Holstein cows and 37 Jersey cows for electronic somatic cell count and determination of the main milk components (protein, fat, total solids, lactose). Milk fat, protein, total solids and production were influenced by breed and the season, with similar tendencies for both breeds in both seasons. Somatic cell count (SCC) showed similar results for both breeds. Holstein cows with intramammary infections (IMI) presented a higher increase in SCC when compared to Jersey cows (P<0.001). In the dry season, 53 animals had IMI in at least one month during the study, which 32 were Holstein and 21 were Jersey cows. In the rainy season, 65 animals had intramammary infection, being 43 Holstein and 22 Jersey cows. The frequency of IMI cases was larger in the rainy season than in the dry season. Jersey cows had a lower chance of showing IMI signs and symptoms than Holstein cows in the rainy season (odds ratio=0.52). The larger number of IMI cases in the rainy season may have led to a lower milk lactose rate for both breeds, thus milk lactose rate can be considered an indicator of IMI status. There was prevalence of contagious pathogens overall in the study. The applied model showed that environmental pathogens were more frequently isolated from the breed Jersey, regardless of the study season. There seems to be differences in the immune response of Jersey and Holstein breeds.

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Effect of somatic cell count on milk fat and protein in different parities and stages of lactation in Holstein cows

Acta agriculturae Slovenica ◽

10.14720/aas.2017.110.1.5 ◽

2017 ◽

Vol 110 (1) ◽

pp. 37

Author(s):

Arash CHEGINI ◽

Navid GHAVI HOSSEIN-ZADEH ◽

Hossein HOSSEINI-MOGHADAM ◽

Abdol Ahad SHADPARVAR

Keyword(s):

Somatic Cell ◽

Cell Count ◽

Milk Fat ◽

Fixed Effects ◽

Somatic Cell Count ◽

Repeated Measurements ◽

Somatic Cell Score ◽

Holstein Cows ◽

Dry Period ◽

Protein Percentage

<p>The objective of this study was to investigate the effect of somatic cell score (SCS) on milk fat and protein in different parities and stages of lactation in Iranian Holstein cows. Records between June 2003 and January 2014 from 208,478 cows in lactations one to nine in 845 herds, comprising 2,456,303 monthly test-day (TD) records were used. The MIXED procedure of the SAS software with repeated measurements was used. The fixed effects of the model were herd, year-season of calving, month of TD, weeks of lactation, previous dry period length and somatic cell score (SCS) and covariate was calving age. Lactations were divided into six stages and analyses were performed within each stage. Also, different lactations were analyzed separately. Increase of SCS led to increase of milk fat and protein percentage and the increase of milk fat and protein associated with SCS was higher in early stages of lactation relative to later stages of lactation. Also, increase of milk fat and protein associated with SCS was higher in the first lactation rather than later lactations and decreased with increase of parity.</p>

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PSII-3 Daily weather patterns associated with colostrum production in dry cows

Journal of Animal Science ◽

10.1093/jas/skab235.581 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 316-316

Author(s):

Andrea Connor ◽

Kayla Alward ◽

Alexandra Nin-Leary ◽

Jane Duncan ◽

Rebecca Cockrum

Keyword(s):

Heat Stress ◽

Somatic Cell ◽

Cell Count ◽

Somatic Cell Count ◽

Poor Quality ◽

Holstein Cows ◽

Linear Regression Models ◽

Dry Period ◽

Hormone Synthesis ◽

Jersey Cows

Abstract Insufficient consumption of colostrum and/or intake of poor-quality colostrum reduces thriftiness and survival of dairy calves. Additionally, heat stress during gestation of primiparous Holstein cows can impact hormone synthesis, leading to decreased colostrum and milk production. Previous research has primarily focused on Holstein cows who have a larger frame compared to other breeds. It is possible heat stress may impact Jersey cow colostrum production differently. Therefore, the objective of this research was to determine the relationship between temperature-humidity index (THI) and colostrum volume and quality in Jersey cows. Colostrum data was collected from Jersey cows (n = 75) from three farms and compared to the average THI values during the dry period. Colostrum data included volume, Brix score, fat, true protein (TP), solids non-fat (SNF), lactose, somatic cell count (SCC), and urea. Daily air temperature and humidity records were determined via local weather stations and used to calculate THI values. These values were averaged for the far-off and close-up periods. The data were analyzed separately for each farm using linear regression models in R version 1.3.1073. Covariates included season, dry period length, date of colostrum collection, and parity. Close-up and far-off THI tended to predict an increased volume (β=0.3656; P = 0.0724) and somatic cell count (β=82.07; P = 0.0964) for Farm 1. Far-off THI was a significant predictor for Brix for Farm 2 (β=0.2482; P ≤ 0.01) and Farm 3 (β=-0.1762; P ≤ 0.01) and increased Brix score in Farm 2 but decreased it in Farm 3. THI was not a significant predictor for any other colostrum values. Based on these results, we suggest that an increased THI during the far-off period potentially increases Brix score without compromising other values. However, more research is needed to further investigate the effects of the close-up period on volume and of covariates on other values.

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Hyperketonemia Predictions Provide an On-Farm Management Tool with Epidemiological Insights

Animals ◽

10.3390/ani11051291 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1291

Author(s):

Ryan S. Pralle ◽

Joel D. Amdall ◽

Robert H. Fourdraine ◽

Garrett R. Oetzel ◽

Heather M. White

Keyword(s):

Somatic Cell ◽

Cell Count ◽

Milk Yield ◽

Milk Fat ◽

Somatic Cell Count ◽

Past Research ◽

Management Tool ◽

Milk Analysis ◽

Linear Regression Models ◽

High Throughput Detection

Prediction of hyperketonemia (HYK), a postpartum metabolic disorder in dairy cows, through use of cow and milk data has allowed for high-throughput detection and monitoring during monthly milk sampling. The objective of this study was to determine associations between predicted HYK (pHYK) and production parameters in a dataset generated from routine milk analysis samples. Data from 240,714 lactations across 335 farms were analyzed with multiple linear regression models to determine HYK status. Data on HYK or disease treatment was not solicited. Consistent with past research, pHYK cows had greater previous lactation dry period length, somatic cell count, and dystocia. Cows identified as pHYK had lower milk yield and protein percent but greater milk fat, specifically greater mixed and preformed fatty acids (FA), and greater somatic cell count (SCC). Differential somatic cell count was greater in second and fourth parity pHYK cows. Culling (60d), days open, and number of artificial inseminations were greater in pHYK cows. Hyperketonemia prevalence decreased linearly in herds with greater rolling herd average milk yield. This research confirms previously identified risk factors and negative outcomes associated with pHYK and highlights novel associations with differential SCC, mixed FA, and preformed FA across farm sizes and production levels.

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