Calf loss continues to be a considerable problem on German dairy farms. Untrained personnel or the lack of best practice routines are potential reasons. Standard operating procedures (SOP) may increase process consistency and can improve animal health and animal welfare. We developed SOP for 8 important tasks in calf care and provided them online to interested dairy farmers and their employees. Five questionnaires were embedded to collect data on demographics, use, perception, and feasibility of SOP. Main objectives of the study were to investigate (1) if there is a gap between the existence of SOP and the wish for SOP, (2) if participants (n = 301) consider ready-made SOP as feasible for their farm and (3) suitable to train new personnel, and (4) if they state their confidence in task execution higher after the courses. We experienced a strong discrepancy between the existence (13.1%) and the wish for SOP (69.4%). Most of the participants rated ready-made SOP as feasible for their farm (66.5%). Eighty-five percent fully agreed or agreed to the statement that SOP are a suitable tool for training new employees. Interestingly, 64.2% of employees mentioned, that they wanted to be involved in the creation of SOP specific to their farm. The SOP-based e-learning courses increased the confidence in performing tasks in calf care, especially concerning tasks that were performed less often such as tube feeding, emergency care, and testing of colostrum quality.
{"title":"Feasibility and acceptance of ready-made standard operating procedures in calf care on German dairy farms","authors":"S. Neukirchner , K.C. Jensen , W. Heuwieser","doi":"10.3168/jds.2023-24597","DOIUrl":"10.3168/jds.2023-24597","url":null,"abstract":"<div><div>Calf loss continues to be a considerable problem on German dairy farms. Untrained personnel or the lack of best practice routines are potential reasons. Standard operating procedures (SOP) may increase process consistency and can improve animal health and animal welfare. We developed SOP for 8 important tasks in calf care and provided them online to interested dairy farmers and their employees. Five questionnaires were embedded to collect data on demographics, use, perception, and feasibility of SOP. Main objectives of the study were to investigate (1) if there is a gap between the existence of SOP and the wish for SOP, (2) if participants (n = 301) consider ready-made SOP as feasible for their farm and (3) suitable to train new personnel, and (4) if they state their confidence in task execution higher after the courses. We experienced a strong discrepancy between the existence (13.1%) and the wish for SOP (69.4%). Most of the participants rated ready-made SOP as feasible for their farm (66.5%). Eighty-five percent fully agreed or agreed to the statement that SOP are a suitable tool for training new employees. Interestingly, 64.2% of employees mentioned, that they wanted to be involved in the creation of SOP specific to their farm. The SOP-based e-learning courses increased the confidence in performing tasks in calf care, especially concerning tasks that were performed less often such as tube feeding, emergency care, and testing of colostrum quality.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9477-9490"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141465134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W.A. Tom , J.V. Judy , P.J. Kononoff , S.C. Fernando
Microbes play an important role in human and animal health, as well as animal productivity. The host microbial interactions within ruminants play a critical role in animal health and productivity and provide up to 70% of the animal's energy needs in the form of fermentation products. As such, many studies have investigated microbial community composition to understand the microbial community changes and factors that affect microbial colonization and persistence. Advances in next-generation sequencing technologies and the low cost of sequencing have led many studies to use 16S rDNA-based analysis tools for interrogation of microbiomes at a much finer scale than traditional culturing. However, methods that rely on single base pair differences for bacterial taxa clustering may inflate or underestimate diversity, leading to inaccurate identification of bacterial diversity. Therefore, in this study, we sequenced mock communities of known membership and abundance to establish filtration parameters to reduce the inflation of microbial diversity due to PCR and sequencing errors. Additionally, we evaluated the effect of the resulting filtering parameters proposed using established bioinformatic pipelines on a study consisting of Holstein and Jersey cattle to identify breed and treatment effects on the bacterial community composition and the impact of filtering on global microbial community structure analysis and results. Filtration resulted in a sharp reduction in bacterial taxa identified, yet retain most sequencing data (retaining >79% of sequencing reads) when analyzed using 3 different microbial analysis pipelines (DADA2, Mothur, USEARCH). After filtration, conclusions from α-diversity and β-diversity tests showed very similar results across all analysis methods. The mock community-based filtering parameters proposed in this study help provide a more realistic estimation of bacterial diversity. Additionally, filtration reduced the variation between microbiome analysis methods and helped to identify microbial community differences that could have been missed due to the large animal-to-animal variation observed in the unfiltered data. As such, we believe the new filtering parameters described in this study will help to obtain diversity estimates that are closer to realistic values, improve the ability to detecting microbial community differences, and help to better understand microbial community changes in 16S rDNA-based studies.
{"title":"Influence of empirically derived filtering parameters, amplicon sequence variant, and operational taxonomic unit pipelines on assessing rumen microbial diversity","authors":"W.A. Tom , J.V. Judy , P.J. Kononoff , S.C. Fernando","doi":"10.3168/jds.2023-24479","DOIUrl":"10.3168/jds.2023-24479","url":null,"abstract":"<div><div>Microbes play an important role in human and animal health, as well as animal productivity. The host microbial interactions within ruminants play a critical role in animal health and productivity and provide up to 70% of the animal's energy needs in the form of fermentation products. As such, many studies have investigated microbial community composition to understand the microbial community changes and factors that affect microbial colonization and persistence. Advances in next-generation sequencing technologies and the low cost of sequencing have led many studies to use 16S rDNA-based analysis tools for interrogation of microbiomes at a much finer scale than traditional culturing. However, methods that rely on single base pair differences for bacterial taxa clustering may inflate or underestimate diversity, leading to inaccurate identification of bacterial diversity. Therefore, in this study, we sequenced mock communities of known membership and abundance to establish filtration parameters to reduce the inflation of microbial diversity due to PCR and sequencing errors. Additionally, we evaluated the effect of the resulting filtering parameters proposed using established bioinformatic pipelines on a study consisting of Holstein and Jersey cattle to identify breed and treatment effects on the bacterial community composition and the impact of filtering on global microbial community structure analysis and results. Filtration resulted in a sharp reduction in bacterial taxa identified, yet retain most sequencing data (retaining >79% of sequencing reads) when analyzed using 3 different microbial analysis pipelines (DADA2, Mothur, USEARCH). After filtration, conclusions from α-diversity and β-diversity tests showed very similar results across all analysis methods. The mock community-based filtering parameters proposed in this study help provide a more realistic estimation of bacterial diversity. Additionally, filtration reduced the variation between microbiome analysis methods and helped to identify microbial community differences that could have been missed due to the large animal-to-animal variation observed in the unfiltered data. As such, we believe the new filtering parameters described in this study will help to obtain diversity estimates that are closer to realistic values, improve the ability to detecting microbial community differences, and help to better understand microbial community changes in 16S rDNA-based studies.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9209-9234"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141465137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Lou , V. Bonfatti , H. Bovenhuis , R. Shi , A. van der Linden , H.A. Mulder , L. Liu , Y. Wang , B. Ducro
Accurate and ex-ante prediction of cows' likelihood of conception (LC) based on milk composition information could improve reproduction management on dairy farms. Milk composition is already routinely measured by mid-infrared (MIR) spectra, which are known to change with advancing stages of pregnancy. For lactating cows, MIR spectra may also be used for predicting the LC. Our objectives were to classify the LC at first insemination using milk MIR spectra data collected from calving to first insemination and to identify the spectral regions that contribute the most to the prediction of LC at first insemination. After quality control, 4,866 MIR spectra, milk production, and reproduction records from 3,451 Holstein cows were used. The classification accuracy and area under the curve (AUC) of 6 models comprising different predictors and 3 machine learning methods were estimated and compared. The results showed that partial least square discriminant analysis (PLS-DA) and random forest had higher prediction accuracies than logistic regression. The classification accuracy of good and poor LC cows and AUC in herd-by-herd validation of the best model were 76.35% ± 10.60% and 0.77 ± 0.11, respectively. All wavenumbers with values of variable importance in the projection higher than 1.00 in PLS-DA belonged to 3 spectral regions, namely from 1,003 to 1,189, 1,794 to 2,260, and 2,300 to 2,660 cm−1. In conclusion, the model can predict LC in dairy cows from a high productive TMR system before insemination with a relatively good accuracy, allowing farmers to intervene in advance or adjust the insemination schedule for cows with a poor predicted LC.
{"title":"Prediction of likelihood of conception in dairy cows using milk mid-infrared spectra collected before the first insemination and machine learning algorithms","authors":"W. Lou , V. Bonfatti , H. Bovenhuis , R. Shi , A. van der Linden , H.A. Mulder , L. Liu , Y. Wang , B. Ducro","doi":"10.3168/jds.2023-24621","DOIUrl":"10.3168/jds.2023-24621","url":null,"abstract":"<div><div>Accurate and ex-ante prediction of cows' likelihood of conception (LC) based on milk composition information could improve reproduction management on dairy farms. Milk composition is already routinely measured by mid-infrared (MIR) spectra, which are known to change with advancing stages of pregnancy. For lactating cows, MIR spectra may also be used for predicting the LC. Our objectives were to classify the LC at first insemination using milk MIR spectra data collected from calving to first insemination and to identify the spectral regions that contribute the most to the prediction of LC at first insemination. After quality control, 4,866 MIR spectra, milk production, and reproduction records from 3,451 Holstein cows were used. The classification accuracy and area under the curve (AUC) of 6 models comprising different predictors and 3 machine learning methods were estimated and compared. The results showed that partial least square discriminant analysis (PLS-DA) and random forest had higher prediction accuracies than logistic regression. The classification accuracy of good and poor LC cows and AUC in herd-by-herd validation of the best model were 76.35% ± 10.60% and 0.77 ± 0.11, respectively. All wavenumbers with values of variable importance in the projection higher than 1.00 in PLS-DA belonged to 3 spectral regions, namely from 1,003 to 1,189, 1,794 to 2,260, and 2,300 to 2,660 cm<sup>−1</sup>. In conclusion, the model can predict LC in dairy cows from a high productive TMR system before insemination with a relatively good accuracy, allowing farmers to intervene in advance or adjust the insemination schedule for cows with a poor predicted LC.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9415-9425"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141198987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. González-Cabrera , S. Álvarez , M. Salomone-Caballero , N. Castro , A. Argüello , L.E. Hernández-Castellano
This study evaluated the effect of feeding colostrum obtained from an intramammary administration (IA) of LPS from Escherichia coli (O55:B5) to dairy goats at parturition, on goat kid performance, biochemical parameters (i.e., calcium, lactate dehydrogenase, glucose, total proteins, albumin, and urea) and immune status (i.e., IgG and IgM) during the first month of life. At birth, goat kids were weighted (d 0) and immediately allocated into either the LPS group (n = 15) or the control (CON) group (n = 21) based on the experimental group of the dam. At parturition, 20 multiparous dairy goats were allocated in 1 of the 2 experimental groups (LPS vs. CON). The LPS group received an IA of saline solution (2 mL) containing 50 µg of LPS in each half udder whereas goats in the CON group received an IA of saline solution (2 mL) without LPS. Goat kids were bottle-fed dam colostrum equivalent to 10% of the birth BW divided in 2 meals (i.e., at 3 and 12 h relative to birth), and then fed twice daily with milk replacer ad libitum. Individual milk intake (MI) and BW were recorded on d 7, 15, 21 and 30 of life. Blood samples were collected on d 0, 1, 2, 4, 7, 15, 21 and 30 after birth. Data were analyzed using the MIXED procedure of SAS (9.4; SAS Institute Inc.). The model included IA, time (T), and their interaction (IA × T) as fixed effects, and sex and litter size as random effects. Both groups showed similar MI, except on d 7 relative to birth as the LPS group showed higher MI than the CON group (910.5 ± 69.77 and 683.9 ± 59.64 mL, respectively; mean ± SEM). No differences in BW or rectal temperature were observed between groups, neither in plasma IgG nor IgM concentrations. Despite the IA did not affect calcium, glucose, LDH, total protein, and albumin concentrations an interaction between the IA and T was observed for urea concentration, showing the LPS group higher urea concentrations than the CON group on d 0 (20.1 ± 1.34 and 20.0 ± 1.25 mg/dL, respectively). In conclusion, feeding colostrum from goats that received an IA of LPS at parturition does not affect goat kid performance, plasma immunoglobulin concentrations and serum metabolites during the first month of life.
{"title":"Intramammary administration of lipopolysaccharides at parturition does not affect the transfer of passive immunity in goat kids","authors":"M. González-Cabrera , S. Álvarez , M. Salomone-Caballero , N. Castro , A. Argüello , L.E. Hernández-Castellano","doi":"10.3168/jds.2024-25073","DOIUrl":"10.3168/jds.2024-25073","url":null,"abstract":"<div><div>This study evaluated the effect of feeding colostrum obtained from an intramammary administration (IA) of LPS from <em>Escherichia coli</em> (O55:B5) to dairy goats at parturition, on goat kid performance, biochemical parameters (i.e., calcium, lactate dehydrogenase, glucose, total proteins, albumin, and urea) and immune status (i.e., IgG and IgM) during the first month of life. At birth, goat kids were weighted (d 0) and immediately allocated into either the LPS group (n = 15) or the control (CON) group (n = 21) based on the experimental group of the dam. At parturition, 20 multiparous dairy goats were allocated in 1 of the 2 experimental groups (LPS vs. CON). The LPS group received an IA of saline solution (2 mL) containing 50 µg of LPS in each half udder whereas goats in the CON group received an IA of saline solution (2 mL) without LPS. Goat kids were bottle-fed dam colostrum equivalent to 10% of the birth BW divided in 2 meals (i.e., at 3 and 12 h relative to birth), and then fed twice daily with milk replacer ad libitum. Individual milk intake (MI) and BW were recorded on d 7, 15, 21 and 30 of life. Blood samples were collected on d 0, 1, 2, 4, 7, 15, 21 and 30 after birth. Data were analyzed using the MIXED procedure of SAS (9.4; SAS Institute Inc.). The model included IA, time (T), and their interaction (IA × T) as fixed effects, and sex and litter size as random effects. Both groups showed similar MI, except on d 7 relative to birth as the LPS group showed higher MI than the CON group (910.5 ± 69.77 and 683.9 ± 59.64 mL, respectively; mean ± SEM). No differences in BW or rectal temperature were observed between groups, neither in plasma IgG nor IgM concentrations. Despite the IA did not affect calcium, glucose, LDH, total protein, and albumin concentrations an interaction between the IA and T was observed for urea concentration, showing the LPS group higher urea concentrations than the CON group on d 0 (20.1 ± 1.34 and 20.0 ± 1.25 mg/dL, respectively). In conclusion, feeding colostrum from goats that received an IA of LPS at parturition does not affect goat kid performance, plasma immunoglobulin concentrations and serum metabolites during the first month of life.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9888-9896"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141786862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Milk serves as an important dietary source of bioactive peptides, offering notable benefits to individuals. Among the antioxidant short peptides (di- and tripeptides) generated from gastrointestinal digestion are characterized by enhanced bioavailability and bioaccessibility, while assessing them individually presents a labor-intensive and expensive challenge. Based on 4 distinct types of AA descriptors (physicochemical, 3-dimensional structural, quantum, and topological attributes) and genetic algorithms for feature selection, 1 and 4 machine learning–predicted models separately for di- and tripeptides with 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging capacity exhibited excellent fitting and prediction ability with random forest regression as machine learning algorithm. Intriguingly, the electronic properties of N-terminal AA were considered as only factor affecting the antioxidant capacity of dipeptides containing both tyrosine and tryptophan. Four peptides from the potential di- and tripeptides exhibited highly predicted values by the constructed predicted models. Subsequently, a total of 45 dipeptides and 52 tripeptides were screened by a customized workflow in goat milk during in vitro simulated digestion. In addition to 5 known antioxidant dipeptides, 9 peptides were quantified during digestion, exhibiting concentrations ranging from 0.04 to 1.78 mg L−1. Particularly noteworthy was the promising in vivo functionality of antioxidant dipeptides with N-terminal tyrosine, supported by in silico assays. Overall, this investigation explored crucial molecular properties influencing antioxidant short peptides and high-throughput screening potential peptides with antioxidant activity from goat milk aided by machine learning, thereby facilitating the discovery of novel functional peptides from milk-derived proteins and paving the way for understanding their metabolites during digestion.
{"title":"Machine learning methods for unveiling the potential of antioxidant short peptides in goat milk-derived proteins during in vitro gastrointestinal digestion","authors":"An Du , Wei Jia , Rong Zhang","doi":"10.3168/jds.2024-24887","DOIUrl":"10.3168/jds.2024-24887","url":null,"abstract":"<div><div>Milk serves as an important dietary source of bioactive peptides, offering notable benefits to individuals. Among the antioxidant short peptides (di- and tripeptides) generated from gastrointestinal digestion are characterized by enhanced bioavailability and bioaccessibility, while assessing them individually presents a labor-intensive and expensive challenge. Based on 4 distinct types of AA descriptors (physicochemical, 3-dimensional structural, quantum, and topological attributes) and genetic algorithms for feature selection, 1 and 4 machine learning–predicted models separately for di- and tripeptides with 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging capacity exhibited excellent fitting and prediction ability with random forest regression as machine learning algorithm. Intriguingly, the electronic properties of N-terminal AA were considered as only factor affecting the antioxidant capacity of dipeptides containing both tyrosine and tryptophan. Four peptides from the potential di- and tripeptides exhibited highly predicted values by the constructed predicted models. Subsequently, a total of 45 dipeptides and 52 tripeptides were screened by a customized workflow in goat milk during in vitro simulated digestion. In addition to 5 known antioxidant dipeptides, 9 peptides were quantified during digestion, exhibiting concentrations ranging from 0.04 to 1.78 mg L<sup>−1</sup>. Particularly noteworthy was the promising in vivo functionality of antioxidant dipeptides with N-terminal tyrosine, supported by in silico assays. Overall, this investigation explored crucial molecular properties influencing antioxidant short peptides and high-throughput screening potential peptides with antioxidant activity from goat milk aided by machine learning, thereby facilitating the discovery of novel functional peptides from milk-derived proteins and paving the way for understanding their metabolites during digestion.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 8837-8851"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141465138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Lora , C. Calderone , L. Prussiani , B. Contiero , S. Malagoli , A. Lotto , G. Cozzi
Blood gas analysis is a great support to the diagnostic process of critically ill patients. Its correct application to the medicine of dairy cows depends on the availability of specific reference intervals that are still difficult to find in the literature. They may vary according to the type of blood sampled, the animals' age and production stage, and climatic conditions. This study aimed at calculating the reference limits for some blood gas parameters in the blood collected from the coccygeal vessels of multiparous Holstein dairy cows. This site of sampling implies the risk of withdrawing blood of unknown origin (venous, arterial, or mixed), but it has a high practical interest for easy and quick performance and minimal animal restraint required. Data from 379 cows were used, and reference limits were produced for pH, partial pressure of carbon dioxide, bicarbonate concentration, total carbon dioxide concentration, oxygen saturation (sO2), hemoglobin (Hb), hematocrit (Hct), base excess, glucose, Na, K, and ionized calcium (iCa). The effects of stage of lactation (5–60 vs. >60 DIM) and season of sampling (cold vs. hot) were investigated, and specific reference limits were produced for each variable and each level of the factors whenever a significant effect was detected. The pH, sO2, K, and iCa were not influenced by season or stage of lactation. All the other blood gas parameters were significantly affected by season of sampling, and Hb, Hct, glucose, and Na were also affected by stage of lactation. Reference limits provided in this study are specific to the site of sampling (coccygeal vessels) and the animal category considered. Further studies are needed to produce reference intervals for other blood gas parameters, cow categories, and blood types.
{"title":"Reference limits for blood gas analysis performed from coccygeal vessels of multiparous Holstein dairy cows: Effects of stage of lactation and season of sampling","authors":"I. Lora , C. Calderone , L. Prussiani , B. Contiero , S. Malagoli , A. Lotto , G. Cozzi","doi":"10.3168/jds.2024-24859","DOIUrl":"10.3168/jds.2024-24859","url":null,"abstract":"<div><div>Blood gas analysis is a great support to the diagnostic process of critically ill patients. Its correct application to the medicine of dairy cows depends on the availability of specific reference intervals that are still difficult to find in the literature. They may vary according to the type of blood sampled, the animals' age and production stage, and climatic conditions. This study aimed at calculating the reference limits for some blood gas parameters in the blood collected from the coccygeal vessels of multiparous Holstein dairy cows. This site of sampling implies the risk of withdrawing blood of unknown origin (venous, arterial, or mixed), but it has a high practical interest for easy and quick performance and minimal animal restraint required. Data from 379 cows were used, and reference limits were produced for pH, partial pressure of carbon dioxide, bicarbonate concentration, total carbon dioxide concentration, oxygen saturation (sO<sub>2</sub>), hemoglobin (Hb), hematocrit (Hct), base excess, glucose, Na, K, and ionized calcium (iCa). The effects of stage of lactation (5–60 vs. >60 DIM) and season of sampling (cold vs. hot) were investigated, and specific reference limits were produced for each variable and each level of the factors whenever a significant effect was detected. The pH, sO<sub>2</sub>, K, and iCa were not influenced by season or stage of lactation. All the other blood gas parameters were significantly affected by season of sampling, and Hb, Hct, glucose, and Na were also affected by stage of lactation. Reference limits provided in this study are specific to the site of sampling (coccygeal vessels) and the animal category considered. Further studies are needed to produce reference intervals for other blood gas parameters, cow categories, and blood types.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9839-9846"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141733099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M.R. Pupo, E.C. Diepersloot, C. Heinzen Jr., L.F. Ferraretto
The objective of this study was to evaluate the effects of dietary fiber source and direct-fed microbial supplementation on lactation performance and feeding behavior of high-producing dairy cows. Sixty-four multiparous Holstein cows (3.5 ± 1.6 [SD] lactations; 76 ± 22 DIM and 735 ± 67 kg of BW at covariate period initiation) and 32 gate feeders were enrolled in a study with a completely randomized design and a 2 × 2 factorial arrangement. Cows and gate feeders were randomly assigned to treatments (16 cows and 8 gate feeds per treatment). Cows were allowed 1 wk to acclimate to feeding gates followed by a 2-wk covariate period. During the acclimation and covariate periods, all cows were fed the same diet to meet or exceed the nutrient requirements. Following the covariate period, cows were enrolled in a 8-wk treatment period during which cows were randomly assigned to 1 of 4 treatments consisting of forage inclusion in the diet, either 45.8% (LF) or 56.7% (HF) of DM, and the supplementation of 75 mL/head per day of a direct-fed microbial (DFM) containing herbal extracts (mallow, mint, and sage), Lactiplantibacillus plantarum, Lentilactobacillus buchneri, Saccharomyces cerevisiae, and sugar cane molasses (Valibiom Mix, Valibiotics AG, Emmen, Switzerland) or without supplementation (CON). The average covariate period value of each variable was used as a covariate. Three-way interactions were observed for DMI and feed efficiency. Dry matter intake was 2 to 3 kg greater for LF-DFM than HF-CON and HF-DFM during wk 2, 3, 5, and 8 of the treatment period. Milk production was 2.1 kg/d greater for LF than HF diets. Both milk fat and MUN concentrations were greater for HF than LF diets. Conversely, milk protein concentration was lower for HF than LF diets. The respiration rate measured in the morning was lower with DFM supplementation than CON. Rectal temperature measured in the morning and averaged for the day were greater for LF than HF diets. Under the conditions of the present study, feeding high-forage diets may be an alternative for producers to reduce feeding costs depending on the price of purchased feeds. However, nonforage fiber sources (i.e., soy hulls) must be considered when producers are challenged by either forage shortages or forage with a lower nutritive value. Additionally, DFM supplementation reduced respiration rate in the morning and affected meal behavior of lactating cows.
{"title":"Dietary fiber source and direct-fed microbial supplementation effects on lactation performance and feeding behavior of high-producing dairy cows","authors":"M.R. Pupo, E.C. Diepersloot, C. Heinzen Jr., L.F. Ferraretto","doi":"10.3168/jds.2024-25033","DOIUrl":"10.3168/jds.2024-25033","url":null,"abstract":"<div><div>The objective of this study was to evaluate the effects of dietary fiber source and direct-fed microbial supplementation on lactation performance and feeding behavior of high-producing dairy cows. Sixty-four multiparous Holstein cows (3.5 ± 1.6 [SD] lactations; 76 ± 22 DIM and 735 ± 67 kg of BW at covariate period initiation) and 32 gate feeders were enrolled in a study with a completely randomized design and a 2 × 2 factorial arrangement. Cows and gate feeders were randomly assigned to treatments (16 cows and 8 gate feeds per treatment). Cows were allowed 1 wk to acclimate to feeding gates followed by a 2-wk covariate period. During the acclimation and covariate periods, all cows were fed the same diet to meet or exceed the nutrient requirements. Following the covariate period, cows were enrolled in a 8-wk treatment period during which cows were randomly assigned to 1 of 4 treatments consisting of forage inclusion in the diet, either 45.8% (LF) or 56.7% (HF) of DM, and the supplementation of 75 mL/head per day of a direct-fed microbial (DFM) containing herbal extracts (mallow, mint, and sage), <em>Lactiplantibacillus plantarum</em>, <em>Lentilactobacillus buchneri</em>, <em>Saccharomyces cerevisiae</em>, and sugar cane molasses (Valibiom Mix, Valibiotics AG, Emmen, Switzerland) or without supplementation (CON). The average covariate period value of each variable was used as a covariate. Three-way interactions were observed for DMI and feed efficiency. Dry matter intake was 2 to 3 kg greater for LF-DFM than HF-CON and HF-DFM during wk 2, 3, 5, and 8 of the treatment period. Milk production was 2.1 kg/d greater for LF than HF diets. Both milk fat and MUN concentrations were greater for HF than LF diets. Conversely, milk protein concentration was lower for HF than LF diets. The respiration rate measured in the morning was lower with DFM supplementation than CON. Rectal temperature measured in the morning and averaged for the day were greater for LF than HF diets. Under the conditions of the present study, feeding high-forage diets may be an alternative for producers to reduce feeding costs depending on the price of purchased feeds. However, nonforage fiber sources (i.e., soy hulls) must be considered when producers are challenged by either forage shortages or forage with a lower nutritive value. Additionally, DFM supplementation reduced respiration rate in the morning and affected meal behavior of lactating cows.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9347-9359"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141733129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L.F. Martins , S.F. Cueva , D.E. Wasson , C.V. Almeida , C. Eifert , M.B. de Ondarza , J.M. Tricarico , A.N. Hristov
<div><div>The objective of this meta-analysis was to quantify the potential of CH<sub>4</sub>-mitigating strategies in dairy cattle when accounting for the effects of treatment dose, dietary nutrient composition, and supplementation period. Data from 218 studies with dairy cattle published between 1963 to 2022 were reviewed. Individual CH<sub>4</sub> mitigation strategies selected for the analysis were algae (<em>Asparagopsis</em> spp.), 3-nitrooxypropanol, nitrate, lipids, plant secondary compounds, and direct-fed microbials (DFM). Response variables evaluated were daily CH<sub>4</sub> emission (g/d), CH<sub>4</sub> yield (g CH<sub>4</sub>/kg DMI), and CH<sub>4</sub> intensity (g CH<sub>4</sub>/kg milk yield [MY] and ECM). Relative mean difference between treatment and control means reported in the studies were calculated and used in the statistical analysis. Robust variance estimation method was used to analyze the effects of CH<sub>4</sub> mitigation strategies. Dose, forage-to-concentrate ratio (F:C), dietary concentrations of CP, ether extract (EE), NDF, ADF, and starch, and supplementation period were used as continuous explanatory variables. Data for algae supplementation were limited and responses to studied species were contrasting but, overall, <em>Asparagopsis</em> spp. effectively decreased daily CH<sub>4</sub> emission, CH<sub>4</sub> yield, and CH<sub>4</sub> intensities by 29.8 ± 4.6%, 23.0 ± 5.3%, 34.0 ± 4.3%, and 22.6 ± 7.3%, respectively. Supplementation of 3-nitrooxypropanol decreased daily CH<sub>4</sub> emission, yield, and intensity (per kg MY and ECM) by 28.2 ± 3.6%, 28.7 ± 2.8%, 29.2 ± 3.1%, and 31.8 ± 2.8%, respectively, compared with control. Decreasing dietary fiber (i.e., F:C, NDF, and ADF), whereas increasing dietary starch concentration increased the efficacy of 3-nitrooxypropanol at mitigating enteric CH<sub>4</sub> emission. Nitrate supplementation decreased CH<sub>4</sub> emission, yield, and intensity (per kg ECM) by 18.5% ± 1.9%, 17.6 ± 1.6%, and 13.0 ± 0.2%, respectively, compared with control. Efficacy of nitrate at mitigating enteric CH<sub>4</sub> yield and CH<sub>4</sub> intensity was positively associated with dose, and efficacy of nitrate at mitigating CH<sub>4</sub> yield was positively associated with dietary starch concentration. Lipid supplementation decreased CH<sub>4</sub> emission, yield, and intensities by up to 14.8 ± 2.3%, respectively, compared with control. Efficacy of lipids supplementation was positively associated with dietary EE, starch, and supplementation period, but negatively associated with dietary ADF concentration. Free oil supplementation tended to increase lipid efficacy by 31% at decreasing CH<sub>4</sub> emission, compared with control. Condensed tannins and plant-derived bioactive compounds decreased CH<sub>4</sub> yield by 11.3 ± 2.9% and 5.7 ± 2.5%, respectively, but oregano did not affect enteric CH<sub>4</sub> emission metrics in the current meta-analysis. Direct-fed microb
{"title":"Effects of dose, dietary nutrient composition, and supplementation period on the efficacy of methane mitigation strategies in dairy cows: A meta-analysis","authors":"L.F. Martins , S.F. Cueva , D.E. Wasson , C.V. Almeida , C. Eifert , M.B. de Ondarza , J.M. Tricarico , A.N. Hristov","doi":"10.3168/jds.2024-24783","DOIUrl":"10.3168/jds.2024-24783","url":null,"abstract":"<div><div>The objective of this meta-analysis was to quantify the potential of CH<sub>4</sub>-mitigating strategies in dairy cattle when accounting for the effects of treatment dose, dietary nutrient composition, and supplementation period. Data from 218 studies with dairy cattle published between 1963 to 2022 were reviewed. Individual CH<sub>4</sub> mitigation strategies selected for the analysis were algae (<em>Asparagopsis</em> spp.), 3-nitrooxypropanol, nitrate, lipids, plant secondary compounds, and direct-fed microbials (DFM). Response variables evaluated were daily CH<sub>4</sub> emission (g/d), CH<sub>4</sub> yield (g CH<sub>4</sub>/kg DMI), and CH<sub>4</sub> intensity (g CH<sub>4</sub>/kg milk yield [MY] and ECM). Relative mean difference between treatment and control means reported in the studies were calculated and used in the statistical analysis. Robust variance estimation method was used to analyze the effects of CH<sub>4</sub> mitigation strategies. Dose, forage-to-concentrate ratio (F:C), dietary concentrations of CP, ether extract (EE), NDF, ADF, and starch, and supplementation period were used as continuous explanatory variables. Data for algae supplementation were limited and responses to studied species were contrasting but, overall, <em>Asparagopsis</em> spp. effectively decreased daily CH<sub>4</sub> emission, CH<sub>4</sub> yield, and CH<sub>4</sub> intensities by 29.8 ± 4.6%, 23.0 ± 5.3%, 34.0 ± 4.3%, and 22.6 ± 7.3%, respectively. Supplementation of 3-nitrooxypropanol decreased daily CH<sub>4</sub> emission, yield, and intensity (per kg MY and ECM) by 28.2 ± 3.6%, 28.7 ± 2.8%, 29.2 ± 3.1%, and 31.8 ± 2.8%, respectively, compared with control. Decreasing dietary fiber (i.e., F:C, NDF, and ADF), whereas increasing dietary starch concentration increased the efficacy of 3-nitrooxypropanol at mitigating enteric CH<sub>4</sub> emission. Nitrate supplementation decreased CH<sub>4</sub> emission, yield, and intensity (per kg ECM) by 18.5% ± 1.9%, 17.6 ± 1.6%, and 13.0 ± 0.2%, respectively, compared with control. Efficacy of nitrate at mitigating enteric CH<sub>4</sub> yield and CH<sub>4</sub> intensity was positively associated with dose, and efficacy of nitrate at mitigating CH<sub>4</sub> yield was positively associated with dietary starch concentration. Lipid supplementation decreased CH<sub>4</sub> emission, yield, and intensities by up to 14.8 ± 2.3%, respectively, compared with control. Efficacy of lipids supplementation was positively associated with dietary EE, starch, and supplementation period, but negatively associated with dietary ADF concentration. Free oil supplementation tended to increase lipid efficacy by 31% at decreasing CH<sub>4</sub> emission, compared with control. Condensed tannins and plant-derived bioactive compounds decreased CH<sub>4</sub> yield by 11.3 ± 2.9% and 5.7 ± 2.5%, respectively, but oregano did not affect enteric CH<sub>4</sub> emission metrics in the current meta-analysis. Direct-fed microb","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9289-9308"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Johanna Ahmann , Jana Friederichs , Wolfgang Büscher , Julia Steinhoff-Wagner
Because calves are born with low levels of antibodies, effective colostrum management is one of the most critical factors for successful calf rearing. A timely and adequate supply of sufficiently high-quality colostrum immediately after birth is essential to ensure the passive immunization of calves. Frozen colostrum reserves are recommended to fulfill the immunological and nutrient requirements of newborn calves, even in exceptional situations; however, the implementation rates on German dairy farms and challenges of realization remain unclear. A 33-question online survey, focused on frozen colostrum reserves, was developed to obtain an overview of colostrum management practices on German dairy farms. The questionnaire was divided into 3 sections: (1) personal data; (2) farm characteristics; (3) colostrum management. Of the 155 responses we received, 63.9% were from female farmers, and 35.5% were from male farmers. Conventional farming was practiced on 89.0% of farms, and organic farming was practiced on 7.1% of farms. Of the respondents, 89.0% froze colostrum. The main reasons for freezing colostrum were (1) the dam does not produce enough colostrum; (2) the dam cannot be milked; or (3) the dam died during birth. Farmers primarily froze colostrum from cows during their third to fifth lactation. Before freezing, 33.1% of the respondents measured indicators in the colostrum to estimate Ig concentrations, whereas 2.3% determined the colostrum quality after freezing. Reusable and disposable polyethylene terephthalate deposits (23.1%, 22.3%) and colostrum bags (20.0%) were the primary containers used to freeze colostrum. The main reasons for not freezing colostrum were the high labor intensity and the availability of fresh colostrum from other cows. Thawing methods included buckets (47.7%) and professional water baths (13.8%). The survey identified areas in which improved knowledge transfer could enhance colostrum management. Furthermore, there appeared to be a lack of specific, feasible instructions for employees concerning the practical implementation of colostrum management. Most importantly, the regular determination and documentation of immunoglobulin concentrations should be emphasized. The added value of stored colostrum, relative to a greater workload, should also be promoted, particularly on smaller farms.
{"title":"Survey on colostrum management by German dairy farmers focusing on frozen colostrum storage","authors":"Johanna Ahmann , Jana Friederichs , Wolfgang Büscher , Julia Steinhoff-Wagner","doi":"10.3168/jds.2024-24716","DOIUrl":"10.3168/jds.2024-24716","url":null,"abstract":"<div><div>Because calves are born with low levels of antibodies, effective colostrum management is one of the most critical factors for successful calf rearing. A timely and adequate supply of sufficiently high-quality colostrum immediately after birth is essential to ensure the passive immunization of calves. Frozen colostrum reserves are recommended to fulfill the immunological and nutrient requirements of newborn calves, even in exceptional situations; however, the implementation rates on German dairy farms and challenges of realization remain unclear. A 33-question online survey, focused on frozen colostrum reserves, was developed to obtain an overview of colostrum management practices on German dairy farms. The questionnaire was divided into 3 sections: (1) personal data; (2) farm characteristics; (3) colostrum management. Of the 155 responses we received, 63.9% were from female farmers, and 35.5% were from male farmers. Conventional farming was practiced on 89.0% of farms, and organic farming was practiced on 7.1% of farms. Of the respondents, 89.0% froze colostrum. The main reasons for freezing colostrum were (1) the dam does not produce enough colostrum; (2) the dam cannot be milked; or (3) the dam died during birth. Farmers primarily froze colostrum from cows during their third to fifth lactation. Before freezing, 33.1% of the respondents measured indicators in the colostrum to estimate Ig concentrations, whereas 2.3% determined the colostrum quality after freezing. Reusable and disposable polyethylene terephthalate deposits (23.1%, 22.3%) and colostrum bags (20.0%) were the primary containers used to freeze colostrum. The main reasons for not freezing colostrum were the high labor intensity and the availability of fresh colostrum from other cows. Thawing methods included buckets (47.7%) and professional water baths (13.8%). The survey identified areas in which improved knowledge transfer could enhance colostrum management. Furthermore, there appeared to be a lack of specific, feasible instructions for employees concerning the practical implementation of colostrum management. Most importantly, the regular determination and documentation of immunoglobulin concentrations should be emphasized. The added value of stored colostrum, relative to a greater workload, should also be promoted, particularly on smaller farms.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9459-9476"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141439895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yapin Wang , Allyson Ipema , Roselinde Goselink , Eline Burgers , Josef Gross , Rupert Bruckmaier , Bas Kemp , Ariette van Knegsel
Extending the voluntary waiting period (VWP) for insemination in dairy cows is of interest as a strategy to reduce the frequency of calving events and inseminate at a moment with fewer fertility problems. Little is known about the calves born from dams with a different VWP followed by a different calving interval (CInt). The objective of the current study was to identify the effect of dam's CInt on body condition, metabolic status, and milk production of their offspring from birth until 100 DIM of the offspring's first lactation. Holstein-Friesian dairy cows (n = 154, 41 primiparous, 113 multiparous) were blocked according to parity, milk yield, and SCC and randomly assigned to a VWP of 50, 125, or 200 d. Female calves (n = 62) from cows with different CInt were monitored from birth until their first calving event as heifer. Certain dams were not successfully inseminated soon after the planned VWP, resulting in differences between the intended VWP and the actual CInt. Calves were regrouped according to their dam's actual CInt (CInt_1: 324–408 d; CInt_2: 409–468 d; CInt_3: 469–586 d). The dam's CInt did not affect calf birth weight. From birth to weaning, the calves born to dams in CInt_1 had a higher plasma nonesterified fatty acids (NEFA) concentration (0.34 mmol/L; CI: 0.30, 0.37) than CInt_2 (0.28 mmol/L; CI: 0.26, 0.31) and CInt_3 (0.26 mmol/L; CI: 0.24, 0.29) calves. Calves born to dams with a shorter CInt (CInt_1) had greater IgG and IgM against keyhole limpet hemocyanin (KLH) than CInt_3 (IgG: 6.05 ± 0.30 vs. 4.64 ± 0.30; IgM: 6.45 ± 0.17 vs. 5.89 ± 0.16, respectively; mean ± SE) before weaning. After weaning till calving, CInt_1 calves tended to have greater plasma NEFA concentration than CInt_3-calves. During the first 100 DIM, a longer CInt of the dams resulted in lower plasma IGF_1 (CInt_2), lower milk lactose (CInt_3), and lower fat- and protein-corrected milk (FPCM; CInt_2) in offspring, compared with shorter CInt of the dams (CInt_1). Collectively, a longer CInt in dams did not affect birth weight of their calves or BW during the weaning or rearing phase. From birth till weaning, a longer CInt in dams resulted in less anti-KLH IgG and lower plasma NEFA concentration in plasma of the calves. During the first lactation of their offspring, a longer CInt in dams can result in a lower plasma IGF_1 and FPCM during the first 100 DIM, although effects were not present in all CInt categories.
{"title":"Effects of calving interval of dairy cows on development, metabolism, and milk performance of their offspring","authors":"Yapin Wang , Allyson Ipema , Roselinde Goselink , Eline Burgers , Josef Gross , Rupert Bruckmaier , Bas Kemp , Ariette van Knegsel","doi":"10.3168/jds.2024-24885","DOIUrl":"10.3168/jds.2024-24885","url":null,"abstract":"<div><div>Extending the voluntary waiting period (VWP) for insemination in dairy cows is of interest as a strategy to reduce the frequency of calving events and inseminate at a moment with fewer fertility problems. Little is known about the calves born from dams with a different VWP followed by a different calving interval (CInt). The objective of the current study was to identify the effect of dam's CInt on body condition, metabolic status, and milk production of their offspring from birth until 100 DIM of the offspring's first lactation. Holstein-Friesian dairy cows (n = 154, 41 primiparous, 113 multiparous) were blocked according to parity, milk yield, and SCC and randomly assigned to a VWP of 50, 125, or 200 d. Female calves (n = 62) from cows with different CInt were monitored from birth until their first calving event as heifer. Certain dams were not successfully inseminated soon after the planned VWP, resulting in differences between the intended VWP and the actual CInt. Calves were regrouped according to their dam's actual CInt (CInt_1: 324–408 d; CInt_2: 409–468 d; CInt_3: 469–586 d). The dam's CInt did not affect calf birth weight. From birth to weaning, the calves born to dams in CInt_1 had a higher plasma nonesterified fatty acids (NEFA) concentration (0.34 mmol/L; CI: 0.30, 0.37) than CInt_2 (0.28 mmol/L; CI: 0.26, 0.31) and CInt_3 (0.26 mmol/L; CI: 0.24, 0.29) calves. Calves born to dams with a shorter CInt (CInt_1) had greater IgG and IgM against keyhole limpet hemocyanin (KLH) than CInt_3 (IgG: 6.05 ± 0.30 vs. 4.64 ± 0.30; IgM: 6.45 ± 0.17 vs. 5.89 ± 0.16, respectively; mean ± SE) before weaning. After weaning till calving, CInt_1 calves tended to have greater plasma NEFA concentration than CInt_3-calves. During the first 100 DIM, a longer CInt of the dams resulted in lower plasma IGF_1 (CInt_2), lower milk lactose (CInt_3), and lower fat- and protein-corrected milk (FPCM; CInt_2) in offspring, compared with shorter CInt of the dams (CInt_1). Collectively, a longer CInt in dams did not affect birth weight of their calves or BW during the weaning or rearing phase. From birth till weaning, a longer CInt in dams resulted in less anti-KLH IgG and lower plasma NEFA concentration in plasma of the calves. During the first lactation of their offspring, a longer CInt in dams can result in a lower plasma IGF_1 and FPCM during the first 100 DIM, although effects were not present in all CInt categories.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"107 11","pages":"Pages 9934-9947"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141439899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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