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2.
J Dairy Sci ; 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39218062

ABSTRACT

Improving production efficiency and minimizing the environmental impact of dairy farming are 2 important goals of the dairy industry. Achieving these objectives requires improving the feed-to-milk conversion efficiency. One way to achieve this goal is through genetic selection. However, measuring feed efficiency in commercial herds is currently not feasible. As such, we conducted a study to evaluate the genetic accuracy of various selection indices derived from Fourier transform mid-infrared (FTIR)-spectra or milk composition. We use 7,793 weekly records on 537 genotyped cows (78,964 SNPs), with information on residual feed intake (RFI), and FTIR-spectra. We fitted various types of selection indexes using the complete FTIR-spectra of milk samples. The estimated heritability of RFI was 0.12 ± 0.02. The accuracy of indirect selection using the FTIR-spectra was maximized using a principal components selection index (0.16 ± 0.07), followed by a Lasso-type penalized selection index (0.14 ± 0.06). We determined that an index based on milk spectral data recorded on ~25 daughters produced a progeny average with an accuracy comparable to direct phenotypic selection for RFI. We conclude that indirect selection for RFI using FTIR-spectra data can be effective for sires with progeny; however, future studies with a larger sample size are needed to validate these results.

3.
J Dairy Sci ; 107(10): 8084-8099, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38876215

ABSTRACT

Feed efficiency is important for economic profitability of dairy farms; however, recording daily DMI is expensive. Our objective was to investigate the potential use of milk mid-infrared (MIR) spectral data to predict proxy phenotypes for DMI based on different cross-validation schemes. We were specifically interested in comparisons between a model that included only MIR data (model M1); a model that incorporated different energy sink predictors, such as body weight, body weight change, and milk energy (model M2); and an extended model that incorporated both energy sinks and MIR data (model M3). Models M2 and M3 also included various cow-level variables (stage of lactation, age at calving, parity) such that any improvement in model performance from M2 to M3, whether through a smaller root mean squared error (RMSE) or a greater squared predictive correlation (R2), could indicate a potential benefit of MIR to predict residual feed intake. The data used in our study originated from a multi-institutional project on the genetics of feed efficiency in US Holsteins. Analyses were conducted on 2 different trait definitions based on different period lengths: averaged across weeks versus averaged across 28 d. Specifically, there were 19,942 weekly records on 1,812 cows across 46 experiments or cohorts and 3,724 28-d records on 1,700 cows across 43 different cohorts. The cross-validation analyses involved 3 different k-fold schemes. First, a 10-fold cow-independent cross-validation was conducted whereby all records from any one cow were kept together in either training or test sets. Similarly, a 10-fold experiment-independent cross-validation kept entire experiments together, whereas a 4-fold herd-independent cross-validation kept entire herds together in either training or test sets. Based on cow-independent cross-validation for both weekly and 28-d DMI, adding MIR predictors to energy sinks (model M3 vs. M2) significantly (P < 10-10) reduced average RMSE to 1.59 kg and increased average R2 to 0.89. However, adding MIR to energy sinks (M3) to predict DMI either within an experiment-independent or herd-independent cross-validation scheme seemed to demonstrate no merit (P > 0.05) compared with an energy sink model (M2) for either R2 or RMSE (respectively, 0.68 and 2.55 kg for M2 in herd-independent scheme). We further noted that with broader cross-validation schemes (i.e., from cow-independent to experiment-independent to herd-independent schemes), the mean and slope bias increased. Given that proxy DMI phenotypes for cows would need to be almost entirely generated in herds having no DMI or training data of their own, herd-independent cross-validation assessments of predictive performance should be emphasized. Hence, more research on predictive algorithms suitable for broader cross-validation schemes and a more earnest effort on calibration of spectrophotometers against each other should be considered.


Subject(s)
Lactation , Milk , Animals , Cattle , Milk/metabolism , Milk/chemistry , Female , Animal Feed/analysis , Eating , Phenotype , Body Weight
4.
J Dairy Sci ; 107(10): 7918-7931, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38876222

ABSTRACT

The objectives of this study were to determine the effects of 2 dietary microbial additives on productive performance and feed efficiency when supplemented to diets of Holstein cows. One hundred seventeen Holstein cows were enrolled at 61 d (31-87 d) postpartum in a randomized complete block design experiment. Cows were blocked by parity group, as nulliparous or multiparous cows and, within parity, by pretreatment ECM yield. Within block, cows were randomly assigned to one of 3 treatments administered as top-dress for 140 d. Treatments consisted of either 100 g of corn meal containing no microbial additive (CON; 15 primiparous and 25 multiparous), 100 g of corn meal containing 5 g of a mixture of Clostridium beijerinckii and Pichia kudriavzevii (G1; 4 × 107 cfu of C. beijerinckii and 1 × 109 cfu of P. kudriavzevii; 14 primiparous and 24 multiparous), or 100 g of corn meal containing 5 g of a mixture of C. beijerinckii, P. kudriavzevii, Butyrivibrio fibrisolvens, and Ruminococcus bovis (G2; 4 × 107 cfu of C. beijerinckii, 1 × 109 cfu of P. kudriavzevii, 1 × 108 cfu of B. fibrisolvens, and 1 × 108 cfu of R. bovis; 15 primiparous and 24 multiparous). Intake of DM, milk yield, and BW were measured daily, whereas milk composition was analyzed at each milking 2 d a week, and body condition was scored twice weekly. Milk samples were collected on d 60 and 62 in the experiment and analyzed for individual fatty acids. The data were analyzed with mixed-effects models with orthogonal contrast to determine the effect of microbial additive (MA; CON vs. 1/2 G1 + 1/2 G2) and type of microbial additive (TMA; G1 vs. G2). Results are described in sequence as CON, G1, and G2. Intake of DM (22.2 vs. 22.4 vs. 22.4 kg/d), BW (685 vs. 685 vs. 685 kg) and the daily BW change (0.40 vs. 0.39 vs. 0.39 kg/d) did not differ among treatments; however, feeding MA tended to increase BCS (3.28 vs. 3.33 vs. 3.36). Supplementing MA increased yields of milk (39.9 vs. 41.3 vs. 41.5 kg/d), ECM (37.9 vs. 39.3 vs. 39.9 kg/d), fat (1.31 vs. 1.37 vs. 1.40 kg/d), TS (4.59 vs. 4.75 vs. 4.79 kg/d), and ECM per kg of DMI (1.72 vs. 1.76 vs. 1.80 kg/kg). Furthermore, cows fed MA increased yields of preformed fatty acids in milk fat (>16C; 435 vs. 463 vs. 488 g/d), particularly UFA (367 vs. 387 vs. 410 g/d), such as linoleic (C18:2 cis-9,cis-12; 30.9 vs. 33.5 vs. 35.4 g/d) and α-linolenic acids (C18:3 cis-9,cis-12,cis-15; 2.46 vs. 2.68 vs. 2.82 g/d) on d 60 and 62 in the experiment. Collectively, supplementing G1 and G2 improved productive performance of cows with no differences between the 2 MA.


Subject(s)
Animal Feed , Diet , Dietary Supplements , Lactation , Milk , Rumen , Animals , Cattle , Female , Diet/veterinary , Rumen/microbiology , Rumen/metabolism , Milk/chemistry
5.
Anim Microbiome ; 6(1): 30, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802977

ABSTRACT

BACKGROUND: Metritis is a prevalent uterine disease that affects the welfare, fertility, and survival of dairy cows. The uterine microbiome from cows that develop metritis and those that remain healthy do not differ from calving until 2 days postpartum, after which there is a dysbiosis of the uterine microbiome characterized by a shift towards opportunistic pathogens such as Fusobacteriota and Bacteroidota. Whether these opportunistic pathogens proliferate and overtake the uterine commensals could be determined by the type of substrates present in the uterus. The objective of this study was to integrate uterine microbiome and metabolome data to advance the understanding of the uterine environment in dairy cows that develop metritis. Holstein cows (n = 104) had uterine fluid collected at calving and at the day of metritis diagnosis. Cows with metritis (n = 52) were paired with cows without metritis (n = 52) based on days after calving. First, the uterine microbiome and metabolome were evaluated individually, and then integrated using network analyses. RESULTS: The uterine microbiome did not differ at calving but differed on the day of metritis diagnosis between cows with and without metritis. The uterine metabolome differed both at calving and on the day of metritis diagnosis between cows that did and did not develop metritis. Omics integration was performed between 6 significant bacteria genera and 153 significant metabolites on the day of metritis diagnosis. Integration was not performed at calving because there were no significant differences in the uterine microbiome. A total of 3 bacteria genera (i.e. Fusobacterium, Porphyromonas, and Bacteroides) were strongly correlated with 49 metabolites on the day of metritis diagnosis. Seven of the significant metabolites at calving were among the 49 metabolites strongly correlated with opportunistic pathogenic bacteria on the day of metritis diagnosis. The main metabolites have been associated with attenuation of biofilm formation by commensal bacteria, opportunistic pathogenic bacteria overgrowth, tissue damage and inflammation, immune evasion, and immune dysregulation. CONCLUSIONS: The data integration presented herein helps advance the understanding of the uterine environment in dairy cows with metritis. The identified metabolites may provide a competitive advantage to the main uterine pathogens Fusobacterium, Porphyromonas and Bacteroides, and may be promising targets for future interventions aiming to reduce opportunistic pathogenic bacteria growth in the uterus.

6.
J Dairy Sci ; 107(8): 6079-6089, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38580147

ABSTRACT

The objective was to assess differences in productive and reproductive performance, and survival associated with vaginal discharge characteristics and fever in postpartum dairy cows located in western and southern states of the United States. This retrospective cohort study included data from 3 experiments conducted in 9 dairies. Vaginal discharge was evaluated twice within 12 DIM and scored on a 5-point scale. The highest vaginal discharge score observed for each cow was used to allocate them into 1 of 5 possible groups (VD group) as follows: VD 1 and 2 (VD 1/2; n = 1,174) = clear mucus or lochia with or without flecks of pus; VD 3 (n = 1,802) = mucopurulent with <50% pus; VD 4 (n = 1,643) = mucopurulent with ≥50% of pus or nonfetid reddish-brownish mucus, n = 1,643; VD 5 = fetid, watery, and reddish-brownish, n = 1,800. All VD 5 cows received treatment according to each herd's protocol. Rectal temperature was assessed in a subset of VD 5 cows, and subsequently divided into fever (rectal temperature ≥39.5°C; n = 334) and no fever (n = 558) groups. A smaller proportion of cows with VD 5 (67.6%) resumed ovarian cyclicity compared with VD 1/2 (76.2%) and VD 4 (72.9%) cows; however, a similar proportion of VD 5 and VD 3 (72.6%) cows resumed ovarian cyclicity. A smaller proportion of VD 5 (85.8%) cows received at least one AI compared with VD 1/2 (91.5%), VD 3 (91.0%), or VD 4 (91.6%) cows. Although we did not detect differences in pregnancy at first AI according to VD, fewer cows with VD 5 (64.4%) were pregnant at 300 DIM than cows with VD 1/2 (76.5%), VD 3 (76.2%), or VD 4 (74.7%). Hazard of pregnancy by 300 DIM was smaller for VD 5 compared with VD 1/2, VD 3, or VD 4 cows. A greater proportion of VD 5 cows were removed from the herd within 300 DIM compared with other VD groups. Milk production was 760 kg lower within 300 DIM for VD 5 compared with VD 2, VD 3, and VD 4, whereas VD 2, VD 3, and VD 4 had similar milk production. We did not detect an association between fever at diagnosis of VD 5 and reproductive performance or milk production. A greater proportion of VD 5 cows without fever were removed from the herd by 300 DIM compared with VD 5 cows with fever. Differences in productive and reproductive performance, and removal of the herd were restricted to fetid, watery, and reddish-brownish vaginal discharge, which was independent of fever.


Subject(s)
Cattle Diseases , Fever , Lactation , Milk , Postpartum Period , Reproduction , Vaginal Discharge , Animals , Cattle , Female , Vaginal Discharge/veterinary , Retrospective Studies , Fever/veterinary , Pregnancy , Cohort Studies
7.
J Dairy Sci ; 107(7): 4357-4369, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38522836

ABSTRACT

In late gestation and in the first weeks postpartum, lipid droplets accumulate in the hepatic tissue resulting in approximately 40% to 50% of the dairy cows developing hepatic lipidosis in the first weeks of lactation. Elevated concentrations of triacylglycerol in the hepatic tissue are associated with increased risk of peripartum diseases and impaired productive performance. Cows with hepatic lipidosis need to dispose the excess of hepatic triacylglycerol, but this is a slow process in the bovine liver and relies on primary mechanisms such as complete oxidation and ketogenesis because of the limited export of triacylglycerols as lipoproteins. Choline is a lipotropic compound because, among other functions, it facilitates the export of lipids from the liver. Supplementing choline as rumen-protected choline (RPC) to diets of feed-restricted dairy cows reduces the degree of triacylglycerol infiltration into the hepatic parenchyma in part by enhancing export of triacylglycerol as nascent lipoprotein. The reduced accumulation of triacylglycerol in hepatic tissue in feed-restricted cows fed RPC might affect secondary pathways involved in hepatic disposal of fatty acids such as increased cellular autophagy and lipophagy and minimize endoplasmic reticulum stress response and hepatocyte inflammation. Collectively, these effects on secondary pathways might further reduce the severity of hepatic lipidosis in cows. One of the benefits of supplementing RPC is improved fat digestibility, perhaps because choline, through phosphatidylcholines, facilitates lipid transport within the enterocyte by increasing the synthesis of chylomicrons. Finally, when supplemented during the transition period, RPC improves productive performance of cows, irrespective of their body condition, that extends well beyond the period of supplementation. This review summarizes the current understanding of hepatic lipidosis in early lactation, recapitulates the absorption, transport and metabolism of choline, and discusses its role on hepatic metabolism and gastrointestinal functions, which collectively results in improved performance in dairy cows.


Subject(s)
Choline , Diet , Lactation , Animals , Choline/metabolism , Cattle , Female , Diet/veterinary , Animal Feed , Nutrients/metabolism , Liver/metabolism , Triglycerides/metabolism
8.
J Dairy Sci ; 107(7): 4881-4894, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38310966

ABSTRACT

The objective was to evaluate the performance of exploratory models containing routinely available on-farm data, behavior data, and the combination of both to predict metritis self-cure (SC) and treatment failure (TF). Holstein cows (n = 1,061) were fitted with a collar-mounted automated-health monitoring device (AHMD) from -21 ± 3 to 60 ± 3 d relative to calving to monitor rumination time and activity. Cows were examined for diagnosis of metritis at 4 ± 1, 7 ± 1, and 9 ± 1 d in milk (DIM). Cows diagnosed with metritis (n = 132), characterized by watery, fetid, reddish/brownish vaginal discharge (VD), were randomly allocated to 1 of 2 treatments: control (CON; n = 62), no treatment at the time of metritis diagnosis (d 0); or ceftiofur (CEF; n = 70), subcutaneous injection of 6.6 mg/kg of ceftiofur crystalline-free acid on d 0 and 3 relative to diagnosis. Cure was determined 12 d after diagnosis and was considered when VD became mucoid and not fetid. Cows in CON were used to determine SC, and cows in CEF were used to determine TF. Univariable analyses were performed using farm-collected data (parity, calving season, calving-related disorders, body condition score, rectal temperature, and DIM at metritis diagnosis) and behavior data (i.e., daily averages of rumination time, activity generated by AHMD, and derived variables) to assess their association with metritis SC or TF. Variables with P-values ≤0.20 were included in the multivariable logistic regression exploratory models. To predict SC, the area under the curve (AUC) for the exploratory model containing only data routinely available on-farm was 0.75. The final exploratory model to predict SC combining routinely available on-farm data and behavior data increased the AUC to 0.87, with sensitivity (Se) of 89% and specificity (Sp) of 77%. To predict TF, the AUC for the exploratory model containing only data routinely available on-farm was 0.90. The final exploratory model combining routinely available on-farm data and behavior data increased the AUC to 0.93, with Se of 93% and Sp of 87%. Cross-validation analysis revealed that generalizability of the exploratory models was poor, which indicates that the findings are applicable to the conditions of the present exploratory study. In summary, the addition of behavior data contributed to increasing the prediction of SC and TF. Developing and validating accurate prediction models for SC could lead to a reduction in antimicrobial use, whereas accurate prediction of cows that would have TF may allow for better management decisions.


Subject(s)
Cattle Diseases , Animals , Cattle , Female , Cattle Diseases/drug therapy , Lactation , Milk , Treatment Failure , Endometritis/veterinary , Endometritis/drug therapy , Anti-Bacterial Agents/therapeutic use
10.
J Dairy Sci ; 107(7): 4381-4393, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38278298

ABSTRACT

The objectives of this retrospective observational study were to investigate the association between BCS at 21 d before calving with prepartum and postpartum DMI, energy balance (EB), and milk yield. Data from 427 multigravid cows from 11 different experiments conducted at the University of Florida (Gainesville, FL) were used. Cows were classified according to their BCS at 21 d before calving as fat (BCS ≥ 4.00; n = 83), moderate (BCS = 3.25-3.75; n = 287), and thin (BCS ≤ 3.00; n = 57). Daily DMI from -21 to -1 and from +1 to +28 DIM was individually recorded. Energy balance was calculated as the difference between net energy for lactation consumed and required. Dry matter intake in fat cows was lower than that in moderate and thin cows both prepartum (fat = 9.97 ± 0.21, moderate = 11.15 ± 0.14, and thin = 11.92 ± 0.22 kg/d) and postpartum (fat = 14.35 ± 0.49, moderate = 15.47 ± 0.38, and thin = 16.09 ± 0.47 kg/d). Dry matter intake was also lower for moderate cows compared with thin cows prepartum, but not postpartum. Energy balance in fat cows was lower than in moderate and thin cows both prepartum (fat = -4.16 ± 0.61, moderate = -1.20 ± 0.56, and thin = 0.88 ± 0.62 Mcal/d) and postpartum (fat = -12.77 ± 0.50, moderate = -10.13 ± 0.29, and thin = -6.14 ± 0.51 Mcal/d). Energy balance was also lower for moderate cows compared with thin cows both prepartum and postpartum. There was a quadratic association between BCS at 21 d before calving and milk yield. Increasing BCS from 2.5 to 3.5 was associated with an increase in daily milk yield of 6.0 kg and 28 d cumulative milk of 147 kg. Increasing BCS from 3.5 to 4.5 was associated with a decrease in daily milk yield of 4.4 kg and 28 d cumulative milk of 116 kg. In summary, a moderate BCS at 21 d before calving was associated with intermediate DMI and EB pre- and postpartum but greater milk yield compared with thinner and fatter cows. Our findings indicate that a moderate BCS is ideal for ensuring a successful lactation.


Subject(s)
Energy Metabolism , Lactation , Milk , Postpartum Period , Animals , Cattle , Female , Milk/metabolism , Pregnancy , Retrospective Studies , Diet/veterinary
11.
JDS Commun ; 5(1): 77-82, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38223375

ABSTRACT

Hepatic lipidosis is a prevalent metabolic disorder, and in vivo models to study intermediary lipid metabolism are needed in dairy cows. Objectives were to apply a method to induce hyperlipidemia and characterize the responses and safety of the intervention in feed-restricted dry Holstein cows at 8 mo of gestation. It was hypothesized that infusion of tyloxapol would induce hyperlipidemia without deleterious effects on health of dairy cows. Pregnant, nonlactating parous Holstein cows (n = 33) at a mean (± standard deviation) of 234 ± 2.2 d of gestation were fed for ad libitum intake on d 1 to 5 and restricted to 41% of the required NEL from d 6 to 13. On d 14, when cows were 247 ± 2.2 d of gestation, cows were kept off feed, and received i.v. a 10% solution of tyloxapol at 120 mg/kg body weight to block hydrolysis of triacylglycerols in very-low-density lipoprotein (VLDL) particles. Blood was sampled for 720 min and analyzed for concentrations of triacylglycerol, VLDL cholesterol, and total cholesterol in serum to reflect hepatic secretion or reduced clearance of such metabolites from blood. Rectal temperature, respiration and heart rates, and clinical signs related to potential anaphylaxis were monitored for the first 30 min relative to tyloxapol infusion, and for any abnormal behavior in the subsequent 24 h. Infusion of tyloxapol progressively increased the concentrations of triacylglycerol, VLDL cholesterol, and total cholesterol in serum. Tyloxapol increased rectal temperature by 0.19°C at 30 min after infusion and increased respiration and heart rates in the first 10 min after infusion by 29% and 40%, respectively. Tyloxapol induced tachycardia (heart rate >80 beats/min) in 66.7% (n = 22), frothy salivation in 39.4% (n = 13), muzzle twitching in 15.2% (n = 5), eyes twitching in 12.1% (n = 4), muscle twitching in 48.5% (n = 16), nystagmus in 6.1% (n = 2), signs of hyperexcitement in 18.2% (n = 6), staggering gait in 18.2% (n = 6), and anaphylaxis in 12.1% (n = 4) of the cows; however, all these signs were transient, and cows returned to normal after 20 min of infusion. No other abnormal behavior was observed past 20 min of tyloxapol infusion. None of the cows aborted and gestation length, calf birth weight, and risk of diseases in the first 21 d postpartum did not differ between cows receiving tyloxapol and a companion group that did not receive tyloxapol. Infusion of tyloxapol induced hyperlipidemia in cows with some animals showing transient reactions to the treatment, but without complications to the cow and the offspring. Application of this model can be useful to study intermediary lipid metabolism in dairy cows.

12.
J Dairy Sci ; 107(3): 1523-1534, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37690722

ABSTRACT

Feed efficiency has become an increasingly important research topic in recent years. As feed costs rise and the environmental impacts of agriculture become more apparent, improving the efficiency with which dairy cows convert feed to milk is increasingly important. However, feed intake is expensive to measure accurately on large populations, making the inclusion of this trait in breeding programs difficult. Understanding how the genetic parameters of feed efficiency and traits related to feed efficiency vary throughout the lactation period is valuable to gain understanding into the genetic nature of feed efficiency. This study used 121,226 dry matter intake (DMI) records, 120,500 energy-corrected milk (ECM) records, and 98,975 metabolic body weight (MBW) records, collected on 7,440 first-lactation Holstein cows from 6 countries (Canada, Denmark, Germany, Spain, Switzerland, and the United States), from January 2003 to February 2022. Genetic parameters were estimated using a multiple-trait random regression model with a fourth-order Legendre polynomial for all traits. Weekly phenotypes for DMI were re-parameterized using linear regressions of DMI on ECM and MBW, creating a measure of feed efficiency that was genetically corrected for ECM and MBW, referred to as genomic residual feed intake (gRFI). Heritability (SE) estimates varied from 0.15 (0.03) to 0.29 (0.02) for DMI, 0.24 (0.01) to 0.29 (0.03) for ECM, 0.55 (0.03) to 0.83 (0.05) for MBW, and 0.12 (0.03) to 0.22 (0.06) for gRFI. In general, heritability estimates were lower in the first stage of lactation compared with the later stages of lactation. Additive genetic correlations between weeks of lactation varied, with stronger correlations between weeks of lactation that were close together. The results of this study contribute to a better understanding of the change in genetic parameters across the first lactation, providing insight into potential selection strategies to include feed efficiency in breeding programs.


Subject(s)
Lactation , Milk , Animals , Female , Cattle/genetics , Lactation/genetics , Eating/genetics , Agriculture , Phenotype
13.
J Dairy Sci ; 106(12): 9078-9094, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37678762

ABSTRACT

Residual feed intake is viewed as an important trait in breeding programs that could be used to enhance genetic progress in feed efficiency. In particular, improving feed efficiency could improve both economic and environmental sustainability in the dairy cattle industry. However, data remain sparse, limiting the development of reliable genomic evaluations across lactation and parity for residual feed intake. Here, we estimated novel genetic parameters for genetic residual feed intake (gRFI) across the first, second, and third parity, using a random regression model. Research data on the measured feed intake, milk production, and body weight of 7,379 cows (271,080 records) from 6 countries in 2 continents were shared through the Horizon 2020 project Genomic Management Tools to Optimise Resilience and Efficiency, and the Resilient Dairy Genome Project. The countries included Canada (1,053 cows with 47,130 weekly records), Denmark (1,045 cows with 72,760 weekly records), France (329 cows with 16,888 weekly records), Germany (938 cows with 32,614 weekly records), the Netherlands (2,051 cows with 57,830 weekly records), and United States (1,963 cows with 43,858 weekly records). Each trait had variance components estimated from first to third parity, using a random regression model across countries. Genetic residual feed intake was found to be heritable in all 3 parities, with first parity being predominant (range: 22-34%). Genetic residual feed intake was highly correlated across parities for mid- to late lactation; however, genetic correlation across parities was lower during early lactation, especially when comparing first and third parity. We estimated a genetic correlation of 0.77 ± 0.37 between North America and Europe for dry matter intake at first parity. Published literature on genetic correlations between high input countries/continents for dry matter intake support a high genetic correlation for dry matter intake. In conclusion, our results demonstrate the feasibility of estimating variance components for gRFI across parities, and the value of sharing data on scarce phenotypes across countries. These results can potentially be implemented in genetic evaluations for gRFI in dairy cattle.


Subject(s)
Lactation , Milk , Pregnancy , Female , Cattle/genetics , Animals , Parity , Time Factors , Lactation/genetics , Eating/genetics , Europe , North America , Animal Feed/analysis
14.
J Dairy Sci ; 106(12): 8942-8952, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37678784

ABSTRACT

Heat stress (HS) during the dry period can affect animal welfare, health, dry matter intake (DMI), and milk production in the subsequent lactation, which will negatively affect the profitability of dairy farms. In this study, the objective was to model the changes in DMI in pregnant nonlactating heat-stressed dairy cows with or without access to evaporative cooling systems. A database was built, composed of individual DMI records from 244 pregnant nonlactating dairy cows from an average -29.3 d (range: -42 to -21 d; SD: ±7.54 d) to -1 d relative to calving (DRC) and housed in environmental conditions in which temperature-humidity index (THI) ranged from 58.4 to 83.3, with or without access to evaporative cooling systems. Generalized additive mixed-effects models were used to describe the relationships of DMI with HS and DRC. Changes in DMI with the increase in THI and the progression of pregnancy in cows with or without evaporative cooling systems were estimated using differential equations. On average, cows housed in barns without evaporative cooling systems had a reduction in DMI of 1.30 kg/d and increased rectal temperature in 0.22°C in relation to those housed in barns with evaporative cooling systems. Dry matter intake decreased as THI increased, but the reduction was greater for noncooled cows as THI values increased. In addition, regardless of the THI, DMI started to decrease at -14 DRC for cooled cows, whereas for noncooled cows it already started at -30 DRC, relative to the previous days evaluated. The intensity of the reduction was lesser for cows that had access to evaporative cooling systems or were in the dry period in May to June as compared with those that were in the dry period in July to August or September to October. The models generated in this study, which include environmental variables, should lead to more accurate predictions of DMI during HS that can be used to formulate diets to meet the needs of the late pregnant cow because it is possible to predict changes in DMI as the heat load and DRC change. Such models are also expected to help dairy nutritionists to decide when and how to apply the dietary strategies available to attenuate the reductions in DMI with the intensity of HS and progression of pregnancy.


Subject(s)
Hot Temperature , Milk , Pregnancy , Female , Cattle , Animals , Lactation , Eating , Heat-Shock Response , Diet/veterinary
15.
J Dairy Sci ; 106(11): 7630-7650, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37641262

ABSTRACT

Objectives were to determine the effects of supplementing rumen-protected choline (RPC) on hepatic composition and secretion of triacylglycerol-rich lipoprotein when cows were subjected to feed restriction to develop fatty liver. It was hypothesized that RPC reduces hepatic triacylglycerol by enhancing secretion of hepatic lipoprotein. Pregnant, nonlactating parous Holstein cows (n = 33) at mean (± standard deviation) 234 ± 2.2 d of gestation were blocked by body condition (3.79 ± 0.49) and assigned to receive 0 g/d (CON), 25.8 g/d choline ion from a RPC product containing 28.8% choline chloride (CC; treatment L25.8), or 25.8 g/d of choline ion from a RPC product containing 60.0% CC (H25.8). Cows were fed for ad libitum intake for the first 5 d and restricted to 41% of the net energy for lactation required for maintenance and pregnancy from d 6 to 13. Intake of metabolizable methionine was maintained at 18 g/d during feed restriction by supplying rumen-protected methionine. Hepatic tissue was sampled on d 6 and 13 and analyzed for triacylglycerol and glycogen, and mRNA expression of hepatic tissue was investigated. On d 14, cows were not fed and received a 10% solution of tyloxapol intravenously at 120 mg/kg of body weight to block hydrolysis of triacylglycerols in very low density lipoprotein (VLDL). Blood was sampled sequentially for 720 min and analyzed for concentration of triacylglycerol and total cholesterol. Lymph was sampled 6 h after tyloxapol infusion, and analyzed for concentrations of fatty acids, ß-hydroxybutyrate, glucose, triacylglycerol, and total cholesterol. A sample of serum collected at 720 min after tyloxapol was assayed for the metabolome composition. The area under the curve (AUC) of serum triacylglycerol, VLDL cholesterol, and total cholesterol were calculated. Orthogonal contrasts evaluated the effect of supplementing RPC (CON vs. [1/2 L25.8 + 1/2 H25.8]) and source of RPC (L25.8 vs. H25.8). Least squares means and standard errors of the means are presented in sequence as CON, L25.8, H25.8. During feed restriction, supplementation of RPC reduced hepatic triacylglycerol (9.0 vs. 4.1 vs. 4.5 ± 0.6%) and increased glycogen contents (1.9 vs. 3.5 vs. 4.1 ± 0.2%). Similarly, supplementation of RPC increased the expression of transcripts involved in the synthesis and assembly of lipoproteins (MTTP), cellular autophagy (ATG3), and inflammation (TNFA), and reduced the expression of transcripts associated with mitochondrial oxidation of fatty acids (HADHA, MLYCD) and stabilization of lipid droplets (PLIN2). After infusion of tyloxapol, RPC increased the AUC for serum triacylglycerol (21,741 vs. 32,323 vs. 28,699 ± 3,706 mg/dL × min) and VLDL cholesterol (4,348 vs. 6,465 vs. 5,740 ± 741 mg/dL × min) but tended to reduce the concentrations of triacylglycerol in lymph (16.7 vs. 13.8 vs. 11.9 ± 1.9 mg/dL). Feeding RPC tended to increase the concentrations of 89 metabolites in serum, after adjusting for false discovery, including 3 acylcarnitines, 1 AA-related metabolite, 11 bile acids, 1 ceramide, 6 diacylglycerols, 2 dihydroceramides, 1 glycerophospholipid, and 64 triacylglycerols compared with CON. Feeding 25.8 g/d of choline ion as RPC mediated increased hepatic triacylglycerol secretion to promote lipotropic effects that reduced hepatic lipidosis in dairy cows.

16.
J Dairy Sci ; 106(12): 9745-9762, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37641295

ABSTRACT

The objective was to characterize transcriptome changes associated with elongation in bovine conceptuses during preimplantation stages. Nonlactating Holstein cows were euthanized 17 d after artificial insemination (AI) and the uterine horn ipsilateral to the CL was flushed with saline solution. Recovered conceptuses were classified as small (1.2 to 6.9 cm; n = 9), medium (10.5 to 16.0 cm; n = 9), or large (18.0 to 26.4 cm; n = 10). Total mRNA was extracted and subjected to transcriptome analyses using the Affymetrix Gene Chip Bovine array. Data were normalized using the GCRMA method and analyzed by robust regression using the Linear Models for Microarray library within Bioconductor in R. Transcripts with P ≤ 0.05 after adjustment for false discovery rate and fold change ≥1.5 were considered differentially expressed. Functional analyses were conducted using the Ingenuity Pathway Analysis platform. Comparisons between large versus small (LvsS), large versus medium (LvsM), and medium versus small (MvsS) conceptuses yielded a total of 634, 240, and 63 differentially expressed transcripts, respectively. Top canonical pathways of known involvement with embryo growth that were upregulated in large conceptuses included actin cytoskeleton (LvsS), integrin signaling (LvsS and LvsM), ephrin receptor (LvsS), mesenchymal transition by growth factor (LvsM), and regulation of calpain protease (LvsS). Transcripts involved with lipid metabolism pathways (LXR/RXR, FXR/RXR, hepatic fibrosis) were associated with the LvsS and LvsM, and some transcripts such as APOC2, APOH, APOM, RARA, RBP4, and PPARGC1A, were involved in these pathways. An overall network summary associated biological downstream effects of invasion of cells, proliferation of embryonic cells, and inhibition of organismal death in the LvsS. In conclusion, differently expressed transcripts in the LvsS comparison were associated with the cell growth, adhesion, and organismal development, although part of these findings could be attributed to differences in circulatory concentrations of progesterone of the cows that bore large and small conceptuses. The large and medium conceptuses developed under similar concentrations of progesterone and presented 240 differently expressed transcripts, associated with cell differentiation, metabolite regulation, and other biological processes.


Subject(s)
Progesterone , Transcriptome , Female , Cattle , Animals , Progesterone/metabolism , Embryo, Mammalian , Gene Expression Profiling/veterinary , Insemination, Artificial/veterinary
17.
J Dairy Sci ; 106(12): 9763-9777, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37641338

ABSTRACT

The objective was to characterize endometrial transcriptome on d 17 of gestation in dairy cows according to conceptus length. Nonlactating Holstein cows (n = 48) were slaughtered 17 d after AI and the uterine horn ipsilateral to the corpus luteum (CL) was flushed with saline solution. Recovered conceptuses were classified as small (1.2-6.9 cm; n = 9), medium (10.5-16.0 cm; n = 9), or large (18.0-26.4 cm; n = 10). Samples of intercaruncular endometrium dissected from the caudal, intermediate, and cranial portions of the uterine horn ipsilateral to the pregnancy were pooled for analyses. Total mRNA was extracted from endometrial tissue and subjected to transcriptome analyses using the Affymetrix Gene Chip Bovine array. Data were normalized using the GCRMA method and analyzed by robust regression using the Linear Models for Microarray library within Bioconductor in R. Transcripts with P ≤ 0.05 after adjustment for false discovery rate and fold change ≥1.5 were considered differentially expressed. Functional analyses were conducted using the Ingenuity Pathway Analysis platform. Comparisons between endometria of cows carrying large versus small (LvsS), large versus medium (LvsM), and medium versus small (MvsS) conceptuses yielded a total of 235, 21, and 94 differentially expressed transcripts, respectively. Top canonical pathways included the antigen presentation pathway and Th1/Th2 activation pathways, both for LvsS and MvsS. Interferon-α and -γ were identified as activated upstream regulators, primarily based on differently expressed transcripts such as IDO1, ISG20, WARS, LGALS9, IFI44, and PSMB9 (LvsS and MvsS). For LvsS, regulator analyses revealed predicted activation of FOXO1, IFN, NFACTC2, IL-12, IL-6, and IL-18, whereas it depicted inhibition of IL10RA and ZBTB1. Changes in these regulators were associated with a downstream activation of leukocytes, as well as quantity and expansion of T lymphocytes. Canonical pathways associated with the comparison LvsM included cell cycle G2/M DNA damage checkpoint regulation, cell cycle control of chromosomal replication. Moreover, tretinoin was predicted, as activated in upstream analysis for the same comparison. In conclusion, most of the differently expressed transcripts in the endometrium on d 17 of gestation were identified between cows carrying small conceptuses compared with counterparts carrying medium and large conceptuses and were involved with pathways associated with modulation of the immune response.


Subject(s)
Endometrium , Transcriptome , Pregnancy , Female , Cattle , Animals , Endometrium/metabolism , Embryo, Mammalian , Uterus/metabolism , Insemination
18.
J Dairy Sci ; 106(11): 8098-8109, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37641346

ABSTRACT

The objective of this study was to identify metabolites associated with metritis and use them for identification of cellular mechanisms affected during transition into lactation. Holstein cows (n = 104) had blood collected in the prepartum period (d -14 ± 6 relative to calving), at calving (d 0), and at the day of metritis diagnosis (d 7 ± 2 after calving). Cows with reddish or brownish, watery, and fetid discharge were diagnosed with metritis (n = 52). Cows with metritis were paired with herdmates without metritis (n = 52) based on days in milk. The metabolome of plasma samples was evaluated using untargeted gas chromatography time-of-flight mass spectrometry. Univariate analyses included t-tests and fold change analyses. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were used for partial least squares discriminant analysis coupled with permutational analysis using 2,000 permutations. Metabolites with false discovery rate adjusted P ≤ 0.10 on t-tests were also used for enriched pathway analyses and identification of cellular processes. Cows that developed metritis had affected cellular processes associated with lower amino acid metabolism in the prepartum period, greater lipolysis, cell death, and oxidative stress at calving and at metritis diagnosis, and greater leukocyte activation at calving, but lower immune cell activation at metritis diagnosis. In summary, cows that developed metritis had plasma metabolomic changes associated with greater lipolysis, oxidative stress, and a dysregulated immune response which may predispose cows to metritis development.

19.
J Dairy Sci ; 106(12): 9244-9259, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37641354

ABSTRACT

The objective was to unravel the peripartum immune and metabolic changes associated with metritis in Holstein cows. Holstein cows (n = 128) had blood collected at -14, 0, 3, and 7 d relative to parturition (DRP). Flow cytometry was used to evaluate blood leukocyte counts, proportions, and activation. Total cells, live cells, single cells, monocytes (CD172α+/CD14+), polymorphonuclears (CD172α+/CD14-/SSChigh), B-cells (CD21+/MHCII+), CD4+ T-cells (CD4+), CD8+ T-cells (CD8+), and γδ T-cells (γδTCR+) were evaluated. Both CD62L and CD11b were used as markers of cell activation. Major histocompatibility complex class II was used as a marker of antigen presentation in monocytes. A Milliplex Bovine Cytokine/Chemokine 08-plex kit was used to evaluate plasma concentrations of IFN-γ, IL-1α, IL-1ß, IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor-α. The body weight (BW) change prepartum was calculated as the difference between calving BW and prepartum BW divided by the number of days between measurements. Plasma fatty acids (FA) were measured at -14 and 0 DRP using untargeted gas chromatography with time-of-flight mass spectrometry. Data were analyzed by ANOVA for repeated measures. Cows that developed metritis (n = 57) had greater prepartum BW, prepartum BW loss, and greater FA concentrations at calving. Plasma FA at calving was positively correlated with IL-1ß. Cows that developed metritis had persistent systemic inflammation, which was demonstrated by greater B-cell activation, greater pro-inflammatory cytokine concentrations, and greater cell damage pre- and postpartum. Postpartum, we observed greater polymorphonuclear cell activation and extravasation but lesser monocytes and CD4+ T-cells activation and extravasation, which suggests postpartum immune tolerance. Greater prepartum adiposity in cows that developed metritis may lead to systemic inflammation pre- and postpartum and immune tolerance postpartum, which may lead to failure to prevent bacterial infection, and development of puerperal metritis.


Subject(s)
Cattle Diseases , Pelvic Inflammatory Disease , Female , Cattle , Animals , CD8-Positive T-Lymphocytes , Gas Chromatography-Mass Spectrometry/veterinary , Postpartum Period , Cytokines , Inflammation/veterinary , Pelvic Inflammatory Disease/veterinary , Lactation
20.
Av. odontoestomatol ; 39(2)abr.-jun. 2023. tab, graf
Article in Spanish | IBECS | ID: ibc-223398

ABSTRACT

Objetivo: Evaluar la precisión de la estimación del sexo y edad utilizando la morfometría de la rama mandibular mediante un modelo de regresión lineal múltiple incluyendo el ancho intercondilear, el ancho bigonial, la longitud coronoides, la longitud de la rama mandibular, la longitud del cóndilo, el ancho máximo de la rama mandibular y el ángulo goniaco en una población adulta peruana 2014-2019. Material y métodos: Se utilizaron 174 tomografías computarizadas de 18 a 60 años de edad y se analizaron las variables ancho intercondileo (AI), ancho bigonial (AB), longitud coronoides (LCr), longitud del cóndilo (LC), longitud de la rama mandibular (LRm), ancho máximo de la rama mandibular (AMRm) y ángulo goniaco (AG) del lado derecho de la mandíbula. Resultados: La prueba t de muestras independientes determinó que la mayor diferencia entre el sexo fue en la variable LC con 6.9225 mm, la función discriminante obtuvo una tasa de clasificación correcta del sexo con 82.7% y con el modelo de regresión logística múltiple se obtuvo una sensibilidad en el sexo femenino de 81.2%, una especificidad de 85.7%, el sexo masculino una sensibilidad de 85.7%, una especificidad de 81.2%, en la edad la correlación más alta fue en AG con -0.252. Conclusión: Los coeficientes más potentes fueron en LRm, AI y AB con 0.608, 0.606 y 0.604 respectivamente. La mayor diferencia se encontró en el ancho intercondilar con 9.3 mm entre los sexos, en general el porcentaje de precisión predictiva fue de 83.9% en una población egipcia muy parecido a este estudio. (AU)


Objective: To evaluate the precision of the estimation of sex and age using the morphometry of the mandibular ramus through a multiple linear regression model including the intercondylar width, the bigonial width, the coronoid length, the length of the mandibular ramus, the length of the condyle, the maximum width of the mandibular ramus and the gonial angle in a Peruvian adult population 2014-2019. Material and methods: 174 computed tomography scans from 18 to 60 years of age were used and the variables intercondylar width (AI), bigonial width (AB), coronoid length (CLr), condyle length (LC), ramus length mandibular ramus (MRm), maximum width of the mandibular ramus (MRAm) and gonial angle (AG) of the right side of the mandible. Results: The independent samples t-test determined that the greatest difference between the sexes was in the LC variable with 6.9225 mm, the discriminant function obtained a correct classification rate of the sex with 82.7% and with the multiple logistic regression model a sensitivity in the female sex of 81.2%, a specificity of 85.7%, the male sex a sensitivity of 85.7%, a specificity of 81.2%, in age the highest correlation was in AG with -0.252. Discussion: The most powerful coefficients were in LRm, AI and AB with 0.608, 0.606 and 0.604 respectively. The greatest difference was found in the intercondylar width with 9.3 mm between the sexes, in general the percentage of predictive accuracy was 83.9% in an Egyptian population very similar to this study. (AU)


Subject(s)
Humans , Male , Female , Adolescent , Young Adult , Adult , Middle Aged , Aged , Morphological and Microscopic Findings , Models, Statistical , Mandible/growth & development , Age and Sex Distribution , Statistics as Topic , Peru/ethnology
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