Caracterização da qualidade do leite e do impacto económico das mastites em três bacias leiteiras em Portugal : ilha de S. Miguel - Açores, Entre-Douro-e-Minho e região Centro do país

Dissertação de Mestrado Integrado em Medicina VeterináriaAs mastites são tidas como a doença mais frequente e com maior impacto económico na produção leiteira. Porém, os produtores nem sempre têm a percepção da dimensão do seu impacto. A circunstância em que a doença se apresenta nas explorações é bastante díspar, evidenciando-se a importância de realizar uma análise económica para cada realidade produtiva. Através da aplicação de um modelo económico, pretendeu-se aferir o custo das mastites em três bacias leiteiras (S. Miguel, Entre-Douro-e-Minho e Centro do país), bem como caracterizar as práticas de maneio em cada região e procurar uma relação entre ambos. Os resultados alcançados demonstraram que o custo de um caso clinico foi de, em média, 118 €, com diferentes valores entre regiões (p<0,05). O impacto económico anual foi de, em média, 147 €/vaca, todavia com grande amplitude de resultados entre explorações. O maneio praticado revela padrões distintos por região, contudo não se comprovou a existência de uma relação entre este e o custo da doença. A análise do maneio das explorações e das consequências económicas da doença, bem como a motivação do produtor para a melhoria contínua da saúde do úbere, são factores cruciais na redução da incidência das mastites e do seu impacto económico.ABSTRACT - Milk quality characterization and economic impact of mastitis in 3 areas of Portugal – S. Miguel island, Entre-Douro-e-Minho e central area of continental Portugal - Mastitis is considered as the most frequent and costly disease affecting dairy farming. Farmers are not always aware of the full dimension of its impact. The circumstances in which the disease manifests itself on different farms may be quite different, leading to the need for an economic analysis to be performed for each production setup. Through the use of an economic model, we aimed at assessing mastitis costs in three dairy areas (S. Miguel, Entre-Douro-e-Minho and e central area of continental Portugal), as well as to characterize management practices in each region, trying subsequently to search for possible relations between them. The results obtained showed that the cost of a clinical case of mastitis was 118€ on average, with different costs per region (p<0.05). The annual economic impact was 147€/cow/year on average, with a large distribution of results between farms. The management practices showed distinct patterns for each region, with no relationship between management and mastitis cost being shown. Farm management procedures and economic consequences of mastitis, as well as farmer motivation for the continual improvement of udder health, are crucial in the reduction of mastitis incidence and its economic impact

Identification of genetic markers associated with hyperketonemia patterns in early lactation Holstein cows.

Ketosis, evidenced by hyperketonemia with elevated blood β-hydroxybutyrate (BHB) levels, is a significant metabolic disorder of dairy cattle, typically diagnosed within the first 6 weeks post-calving when high energy levels are essential to milk production. Our study aimed to identify genetic markers linked to hyperketonemia (HYK) patterns in Holstein cows during early lactation and compare these to HYK-negative cows. We screened 964 cows for HYK using a threshold of BHB ≥1.2 mmol/L during the first 2 weeks postpartum (screening period, SP). Cows that tested negative initially were retested the following week. Cows were deemed HYK-negative (CON group) if BHB levels were below 1.2 mmol/L in both tests, while those with BHB levels exceeding this threshold at any test were treated and classified as HYK-positive (HYK+). Post-treatment, HYK+ cows were monitored for two-week follow-up period (FP) and classified based on their recovery: cured (CUR; consistently low BHB), recurrent (REC; fluctuating BHB levels), severe (SEV; high initial BHB that decreased), or chronic (CHR; persistently high BHB). Using 489 cows that were genotyped, a GWAS was conducted using GCTA software, revealing significant associations of several SNPs across different HYK patterns when compared to the CON group. These SNPs were primarily linked to genes affecting milk traits and were enriched in biological pathways relevant to protein glycosylation, inflammatory response, glucose homeostasis, and fatty acid synthesis. Our findings highlight genomic regions, potential candidate genes, and biological pathways related to ketosis, underscoring potential targets for improving health management in dairy cattle. These insights could lead to better strategies for managing ketosis through genetic selection, ultimately enhancing dairy cattle welfare and productivity. Further research with a larger number of cows is recommended to validate these findings and help confirm the implicated SNPs and genes

The effect of prepartum negative dietary cation-anion difference and serum calcium concentration on blood neutrophil function in the transition period of healthy dairy cows

Our objectives were to assess the effects of a diet with a negative dietary cation-anion difference (DCAD) before calving on phagocytosis (Pc) and oxidative burst (OB) function of circulating neutrophils, and to determine the associations of serum ionized (iCa) and total calcium (tCa) concentrations with Pc and OB in transition dairy cows. We hypothesized that multiparous cows fed a negative DCAD diet prepartum would have greater iCa and tCa, and thus improved Pc and OB. From 3 wk before expected parturition until calving, 38 healthy multiparous cows from 3 farms were assigned to negative DCAD treatment (TRT; −100 mEq/kg of diet dry matter; n = 21) or a control (CON; 95 mEq/kg of dry matter; n = 17) diet. Each farm was on one treatment or the other at a time, but all farms contributed cows to both groups. Urine pH was measured weekly and in TRT was 6.1 ± 0.8 with 80% of 50 samples <7 and 74% ≤ 6.5. Phagocytosis, OB, iCa, and tCa were measured at d −7, 1, and 4 relative to calving. Median fluorescence intensity for Pc (MFIP) and OB (MFIOB), and the shift of percentage of cells active for Pc (PPc) and OB (POB) were measured in isolated, stimulated neutrophils via flow cytometry. Outcomes were assessed with mixed linear regression models accounting for repeated measures. There were no differences between treatments in the 4 neutrophil function outcomes. Although MFIOB varied over time, there were no interactions of treatment with time for any outcome. Serum ionized and tCa did not differ between TRT and CON. The least squares means ± standard deviation for iCa were: d −7, 1.23 ± 0.12 vs. 1.21 ± 0.12; d 1, 1.07 ± 0.12 vs. 1.02 ± 0.12; d 4, 1.16 ± 0.12 vs. 1.17 ± 0.12 mmol/L for TRT and CON, respectively; and for tCa: d −7 2.39 ± 0.25 vs 2.44 ± 0.31; d 1, 2.01 ± 0.25 vs 1.97 ± 0.31; d 4, 2.33 ± 0.25 vs 2.32 ± 0.31 mmol/L, respectively. The proportion of blood samples with tCa <2.15mmol/L at d −7, 1 and 4 was 5, 76, and 13%, respectively, with no differences between TRT and CON. Correlations of iCa or tCa with each of the 4 polymorphonuclear leukocyte (PMN) function outcomes were weak (r < |0.3|). We did not observe the hypothesized differences in aspects of innate immunity in clinically healthy multiparous cows fed a negative DCAD. We underline that cows that experienced clinical disease were excluded from this study, which is important for interpretation of the results

Identification of genetic markers associated with hyperketonemia patterns in early lactation Holstein cows

Additional File 1- Table S1. Descriptive statistics for blood BHB concentration (mmol/L) in Holstein cows were included in an observational study to assess their hyperketonemia patterns in the two weeks postpartum followed by diagnosis and treatment of the condition. Additional File 1- Table S2. Results indicated differences in blood BHB concentration (mmol/L) among HYK patterns in Holstein cows were included in an observational study to assess their hyperketonemia patterns in the two weeks postpartum followed by diagnosis and treatment of the condition. Additional File 2- Spreadsheet S1. List of genes, SNP and their functional consequences associated with HYK identified through cured vs. control (CUR-CON) contrast. Spreadsheet S2. List of genes, SNP and their functional consequences associated with HYK identified through severe vs. control (SEV-CON) contrast. Spreadsheet S3. List of genes, SNP and their functional consequences associated with HYK identified through chronic vs. control (CHR-CON) contrast, Spreadsheet S4. List of genes, SNP and their functional consequences associated with HYK identified through recurrent vs. control (REC-CON) contrast. Additional File 3- Spreadsheet S1. Pathways associated with genes identified to cured vs. control (CUR-CON) contrast, Spreadsheet S2. Pathways associated with genes identified to severe vs. control (SEV-CON) contrast, Spreadsheet S3. Pathways associated with genes identified to chronic vs. control (CHR-CON) contrast, Spreadsheet S4. Pathways associated with genes identified to recurrent vs. control (REC-CON) contrast, Spreadsheet S6. Pathways associated with genes set identified among 4 analyzed contrasts (Cured-CUR, severe-SEV, chronic-CHR and recurrent-RECU compared with control-CON, respectively), Spreadsheet S7. Protein Interaction network associated with genes set identified among 4 analyzed contrasts (Cured-CUR, severe-SEV, chronic-CHR and recurrent-RECU compared with control-CON, respectively). Additional File 4- Spreadsheet S1. Go terms and QTL associated with genes and SNPs related to HYK identified through cured vs. control (CUR-CON) contrast analysis, Spreadsheet S2. Go terms and QTL associated with genes and SNPs related to HYK identified through severe vs. control (SEV-CON) contrast, Spreadsheet S3. Go terms and QTL associated with genes and SNPs related to HYK identified through chronic vs. control (CHR-CON) contrast, Spreadsheet S4. Go terms and QTL associated with genes and SNPs related to HYK were identified through recurrent vs. control (REC-CON) contrast

Identification of genetic markers associated with hyperketonemia patterns in early lactation Holstein cows

&lt;p&gt;&lt;strong&gt;Additional File&lt;/strong&gt; &lt;strong&gt;1&lt;/strong&gt;- &lt;strong&gt;Table S1.&nbsp;&lt;/strong&gt;Descriptive statistics for blood BHB concentration (mmol/L) in Holstein cows that were included in an observational study to assess their hyperketonemia patterns in the two weeks postpartum (SP period). &lt;strong&gt;Additional File1&lt;/strong&gt;- &lt;strong&gt;Table S2.&lt;/strong&gt; Descriptive statistics for blood BHB concentration (mmol/L) in Holstein cows that were included in an observational study to assess their hyperketonemia (HYK) patterns in the two weeks post HYK diagnosis and treatment of the condition (FP period).&lt;strong&gt; Additional File&lt;/strong&gt; &lt;strong&gt;1&lt;/strong&gt;- &lt;strong&gt;Table S3.&nbsp;&lt;/strong&gt;Results indicated differences in blood BHB concentration (mmol/L) among HYK patterns in Holstein cows were included in an observational study to assess their hyperketonemia patterns in the two weeks postpartum followed by diagnosis and treatment of the condition.&lt;strong&gt;&nbsp;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Additional File&lt;/strong&gt; &lt;strong&gt;2&lt;/strong&gt;- &lt;strong&gt;Spreadsheet S1.&lt;/strong&gt; List of genes, SNP and their functional consequences associated with HYK identified through cured vs. control (CUR-CON) contrast, &lt;strong&gt;Spreadsheet S2.&lt;/strong&gt; List of genes, SNP and their functional consequences associated with HYK identified through severe vs. control (SEV-CON) contrast. &lt;strong&gt;Spreadsheet S3.&lt;/strong&gt; List of genes, SNP and their functional consequences associated with HYK identified through chronic vs. control (CHR-CON) contrast,&lt;strong&gt; Spreadsheet S4.&lt;/strong&gt; List of genes, SNP and their functional consequences associated with HYK identified through recurrent vs. control (REC-CON) contrast.&lt;strong&gt;&nbsp;&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Additional File&lt;/strong&gt; &lt;strong&gt;3&lt;/strong&gt;-&lt;strong&gt; Spreadsheet S1.&nbsp;&lt;/strong&gt;Pathways associated with genes identified to cured vs. control (CUR-CON) contrast, &lt;strong&gt;Spreadsheet S2.&nbsp;&lt;/strong&gt;Pathways associated with genes identified to severe vs. control (SEV-CON) contrast,&lt;strong&gt;&nbsp;Spreadsheet S3.&nbsp;&lt;/strong&gt;Pathways associated with genes identified to chronic vs. control (CHR-CON) contrast,&lt;strong&gt;Spreadsheet S4.&nbsp;&lt;/strong&gt;Pathways associated with genes identified to recurrent vs. control (REC-CON) contrast,&lt;strong&gt;Spreadsheet S6.&lt;/strong&gt; Pathways associated with genes set identified among 4 analyzed contrasts (Cured-CUR, severe-SEV, chronic-CHR and recurrent-RECU compared with control-CON, respectively), &lt;strong&gt;Spreadsheet S7.&lt;/strong&gt; Protein Interaction network associated with genes set identified among 4 analyzed contrasts (Cured-CUR, severe-SEV, chronic-CHR and recurrent-RECU compared with control-CON, respectively).&lt;/p&gt;&lt;p&gt;&nbsp;&lt;strong&gt;Additional File4&lt;/strong&gt;- &lt;strong&gt;Spreadsheet S1.&lt;/strong&gt; Go terms and QTL associated with genes and SNPs related to HYK identified through cured vs. control (CUR-CON) contrast analysis, &lt;strong&gt;Spreadsheet S2.&lt;/strong&gt; Go terms and QTL associated with genes and SNPs related to HYK identified through severe vs. control (SEV-CON) contrast, &lt;strong&gt;Spreadsheet S3.&lt;/strong&gt; Go terms and QTL associated with genes and SNPs related to HYK identified through chronic vs. control (CHR-CON) contrast, &lt;strong&gt;Spreadsheet S4.&lt;/strong&gt; Go terms and QTL associated with genes and SNPs related to HYK were identified through recurrent vs. control (REC-CON) contrast.&lt;/p&gt