Financial risk and resiliency on US dairy farms: Measures, thresholds, and management implications.

Given the revenue and cost volatility with resulting tight profit margins in dairy farming, it is increasingly important to measure, monitor, and understand farm financial risk. Solvency, liquidity, debt repayment capacity, and financial efficiency measures can reveal potential problem areas and assist in financial risk management. Financial risk is defined as uncertainty about interest rates, willingness of lender to keep or put money into the business, ability to meet cash flow needs, and the market value of collateral. Financial resilience is defined as the ability to withstand events that impact firm net income. Solvency was measured by equity to asset ratio. Liquidity was measured by current ratio. Repayment capacity was measured by debt coverage ratio. Financial efficiency was measured by operational expense ratio and net farm income ratio. Critical thresholds for these farm financial measures include those determined by US agricultural lenders since maintaining access to outside capital is important for farm financial management. To demonstrate these concepts and measure financial risk and resilience, this research uses farm data from a balanced panel of 105 New York dairy farms from 2010 through 2019. Results reveal that there were 4 average, 2 good, and 4 poor financial years for these operations on average as measured by farm profitability. Solvency positions were relatively stable being based on long-term asset and liability values. During the poor years, the percent of farms below danger thresholds for liquidity and debt repayment capacity spiked.

Estimating milk yield and value losses from increased somatic cell count on US dairy farms.

Milk loss due to increased somatic cell counts (SCC) results in economic losses for dairy producers. This research uses 10 mo of consecutive dairy herd improvement data from 2013 and 2014 to estimate milk yield loss using SCC as a proxy for clinical and subclinical mastitis. A fixed effects regression was used to examine factors that affected milk yield while controlling for herd-level management. Breed, milking frequency, days in milk, seasonality, SCC, cumulative months with SCC greater than 100,000 cells/mL, lactation, and herd size were variables included in the regression analysis. The cumulative months with SCC above a threshold was included as a proxy for chronic mastitis. Milk yield loss increased as the number of test days with SCC ≥100,000 cells/mL increased. Results from the regression were used to estimate a monetary value of milk loss related to SCC as a function of cow and operation related explanatory variables for a representative dairy cow. The largest losses occurred from increased cumulative test days with a SCC ≥100,000 cells/mL, with daily losses of $1.20/cow per day in the first month to $2.06/cow per day in mo 10. Results demonstrate the importance of including the duration of months above a threshold SCC when estimating milk yield losses. Cows with chronic mastitis, measured by increased consecutive test days with SCC ≥100,000 cells/mL, resulted in higher milk losses than cows with a new infection. This provides farm managers with a method to evaluate the trade-off between treatment and culling decisions as it relates to mastitis control and early detection.

Using institutional and behavioural economics to examine animal health systems.

Economics provides a framework for understanding management decisions and their policy implications for the animal health system. While the neoclassical economic model is useful for framing animal health decisions on the farm, some of its assumptions and prescriptive results may be unrealistic. Institutional and behavioural economics address some of these potential shortcomings by considering the role of information, psychology and social factors in decisions. Framing such decisions under contract theory allows us to consider asymmetric information between policy-makers and farmers. Perverse incentives may exist in the area of preventing and reporting disease. Behavioural economics examines the role of internal and external psychological and social factors. Biases, heuristics, habit, social norms and other such aspects can result in farm decision-makers arriving at what might be considered irrational or otherwise sub-optimal decisions. Framing choices and providing relevant information and examples can alleviate these behavioural issues. The implications of this approach for disease policy and an applied research and outreach programme to respond to animal diseases are discussed.

L'économie fournit un cadre permettant de comprendre les décisions managériales et leurs conséquences sur les politiques à mener en matière de santé animale. Le modèle économique néoclassique permet, certes, d'encadrer utilement les décisions de santé animale à l'échelle de l'exploitation, mais certaines de ses hypothèses et des préconisations qui en résultent paraissent irréalistes. Ces carences potentielles sont en partie traitées par l'économie institutionnelle et comportementale, qui prend en considération le rôle joué par l'information, par la psychologie et par les facteurs sociaux dans le processus de prise de décision. La formulation de ces décisions dans les termes de la théorie des contrats nous permet de prendre en compte l'asymétrie de l'information entre les décideurs politiques et les éleveurs. Des incitations à effets pervers peuvent exister dans le domaine de la prévention et de la notification des maladies. L'économie comportementale examine le rôle de facteurs internes et externes de nature psychologique et sociale. Les biais, les raisonnements heuristiques, le poids de l'habitude, les normes sociales et d'autres influences similaires peuvent donner lieu à des décisions que l'on peut considérer comme irrationnelles ou médiocres. La formulation des choix effectués et la diffusion d'informations pertinentes et d'exemples sont des moyens d'atténuer ces déterminations comportementales. Les auteurs examinent les conséquences de cette approche dans l'élaboration des politiques sanitaires et présentent un programme de recherche appliquée et d'information sur le terrain pour faire face aux maladies animales.

La economía ofrece un marco de referencia para entender las decisiones de gestión y sus consecuencias normativas para todo sistema zoosanitario. Mientras que el modelo económico neoclásico resulta útil para inscribir las decisiones de sanidad animal en el contexto de la explotación, a veces algunos de sus postulados y resultados prescriptivos no son realistas. La economía institucional y conductual da respuesta a varias de esas posibles insuficiencias porque tiene en cuenta el papel que cumplen la información, la psicología y los factores sociales a la hora de adoptar decisiones. El hecho de encuadrar tales decisiones en la teoría de los contratos nos permite tener en cuenta la asimetría de la información que manejan los planificadores de políticas y los productores agropecuarios. También puede haber incentivos perversos en cuanto a la prevención y notificación de enfermedades. La economía conductual examina la función de factores de orden social y psicológico, tanto internos como externos. Los prejuicios, la heurística, los hábitos, las normas sociales y otros aspectos de parecida índole pueden llevar a los responsables de una explotación a adoptar decisiones que cabría considerar irracionales, o en cualquier caso no idóneas. El hecho de inscribir en un marco de referencia las opciones existentes y de facilitar información y ejemplos pertinentes puede reducir el peso de estos problemas de conducta. El autor examina lo que estos métodos pueden aportar a las políticas sanitarias y los programas de divulgación e investigación aplicada para la lucha contra las enfermedades animales.

Effect of GnRH and hCG on progesterone concentration and ovarian and luteal blood flow in diestrous mares.

The objective of the present study was to investigate the effect of reproductive hormones (GnRH, hCG, LH and progesterone) on the regulation of corpus luteum (CL) and ovarian blood flow. Diestrous mares received a single treatment of saline, 100µg gonadorelin (GnRH), or 1500IU hCG 10days after ovulation. Plasma LH and progesterone concentrations, resistance index (RI) for ovarian artery blood-flow, and percentage of corpus luteum (CL) with color-Doppler signals of blood flow were determined immediately before treatment (hour 0) and at hours 0.25, 0.5, 1, 1.5, 2, 3, 4, 5, and 6. In the GnRH group, LH increased (P<0.0001) between hours 0 and 0.25 and then progressively decreased; concentration of LH was not affected in the saline and hCG groups. Progesterone concentration was not different among groups. In the GnRH group, RI tended (P<0.07) to decrease between hours 0 and 1.5 and increased (P<0.01) between hours 1.5 and 4. In the hCG group, two transient RI decreases (P<0.05) occurred before hour 2. The percentage change from hour 0 in the percentage of CL with blood-flow signals was greater at hour 0.5 in the GnRH group than in the saline group and was intermediate in the hCG group. The similarity among groups in progesterone concentration indicated that changes in progesterone were not involved in the GnRH and hCG stimulation of ovarian vascular perfusion. Effects of treatment might have been mediated through LH; however, since hCG biological activity is primarily LH-like, the differences in timing and degree of ovarian and luteal blood flow changes after GnRH or hCG administration in the present study suggest that GnRH might have a direct effect on ovarian blood vessels and vascular control.

Temporality of two-way functional coupling between FSH and follicles in heifers.

The intervals from removal of FSH suppressants by follicle ablation to an increase in FSH and from an increase in FSH to an increase in follicle diameter were determined hourly during follicular wave 1 in a follicles-intact group (n = 7) and a follicles-ablated group (n = 20). Follicles other than the largest subordinate follicle of wave 1 (SF1) were ablated when the dominant follicle of wave 1 (DF1) was about 11 mm (hour 0) and FSH concentration was basal. In an ablated-regressed subgroup (n = 5), SF1 diameter decreased constantly during hours 0 to 8. In an ablated-maintained subgroup (n = 15), SF1 decreased for 2 or 3 hours and then increased (n = 11) or increased constantly (n = 4). Average diameter of SF1 during 8 hours was greater (P < 0.01) in the maintained subgroup (8.3 ± 0.07 mm) than in the regressed subgroup (7.3 ± 0.09 mm). Concentration of FSH increased (P < 0.02) similarly between the two ablated subgroups but did not change during the 8 hours in the follicles-intact group. In each wave in the ablated-maintained subgroup with a decrease and then an increase in SF1 diameter (n = 11), the SF1 increase was preceded by an FSH increase. The interval from hour 0 (removal of source of FSH suppressants) to the beginning of an increase in FSH was 0.8 ± 0.3 hours. The interval from the beginning of an FSH increase to the beginning of an SF1 diameter increase was 2.8 ± 0.4 hours. The immediate coupling and decoupling between follicles and FSH may be essential aspects of follicle deviation during selection of DF1 by impeding the growth rate of the future SF1 before it can attain the developmental stage needed for continued growth during low FSH.

Public and farmer perceptions of dairy cattle welfare in the United States.

This research used surveys of the public and dairy farmers in the United States to assess perceptions and attitudes related to dairy cattle welfare. Sixty-three percent of public respondents indicated that they were concerned about dairy cattle welfare. Most public respondents agreed that animal welfare was more important than low milk prices but that the average American did not necessarily agree. Most public respondents had not viewed media stories related to dairy cattle welfare. Respondents who had viewed these stories did so on television or Internet. The United States Department of Agriculture (USDA) was viewed as the most accurate source of information related to dairy cattle welfare, followed by the Humane Society of the United States (HSUS) and the American Veterinary Medicine Association (AVMA). Both public and dairy farmer respondents viewed farmers as having the most influence on dairy cattle welfare. However, there was a general pattern of public respondents indicating that groups including USDA, HSUS, and AVMA had a relatively larger influence on dairy cattle welfare than did farmer respondents. In contrast, dairy farmers indicated that individual actors-farmers, veterinarians, consumers-had more influence than the public indicated. When asked about production practices, most public respondents indicated that they would vote for a ban on antibiotic use outside of disease treatment or for the mandated use of pain control in castration. However, a minority indicated they would vote to ban the use of recombinant bovine somatotropin (rbST) or to pay a premium for milk produced without rbST. With respect to explaining public support for the production practice bans and limits, respondents were more likely to vote for the restrictions if they were older, female, had higher income, or had viewed animal welfare stories in the media.

Characteristics and functions of a minor FSH surge near the end of an interovulatory interval in Bos taurus heifers.

The apparent function of a minor FSH surge based on temporality with follicular events was studied in 10 heifers with 2 follicular waves per interovulatory interval. Individual follicles were tracked from their emergence at 2 mm until their outcome was known, and a blood sample was collected for FSH and LH assay every 12 h from day -14 (day 0 = ovulation) to day 4. A minor FSH surge occurred in each heifer (peak, day -4.6 ± 0.2). Concentration of LH increased (P < 0.05) during the FSH increase of the minor surge but did not decrease during the FSH decrease. A minor follicular wave with 8.2 ± 2.0 follicles occurred in 6 of 10 heifers. The maximal diameter (mean, 3.4 ± 0.9 mm) of 77% of the minor-wave follicles occurred in synchrony on day -4.4 ± 0.4. Most (59%) of minor-wave follicles regressed before ovulation and 41% decreased and then increased in diameter (recovered) on day -1.9 ± 0.3 to become part of the subsequent wave 1. A mean of 3.7 ± 0.9 regressing subordinate follicles from wave 2 recovered on the day before or at the peak of the minor FSH surge. The growth rate of the preovulatory follicle decreased (P < 0.02) for 3 d before the peak of the minor FSH surge and then increased (P < 0.03). Concentration of LH increased slightly but significantly temporally with the resurgence in growth rate of the preovulatory follicle. A minor LH surge peaked (P < 0.0002) on day 3 at the expected deviation in growth rates between the future dominant and subordinate follicles. Results indicated on a temporal basis that the recovery of some regressing subordinate follicles of wave 2 was attributable to the minor FSH surge. The hypothesis was supported that some regressing follicles from the minor follicular wave recover to become part of wave 1.

Systemic effect of follicle-stimulating hormone and intraovarian effect of the corpus luteum on complete regression vs recovery of regressing wave-2 follicles in heifers.

Each subordinate of the second follicular wave (wave 2) was monitored, and the outcome was classified as fully regressed (decreased in diameter to 2 mm) or recovered (decreased initially and then increased to become a growing follicle of the subsequent wave 1). The changing diameter of each follicle after emergence at 2 mm and plasma concentration of follicle-stimulating hormone were determined every 12 h from the day of ovulation (Day 0) to 4 d after the subsequent ovulation in heifers with 2 follicular waves per interovulatory interval (n = 10). The number and percentage of wave-2 subordinates that initially regressed and then recovered (7.2 ± 1.0 follicles; 33.2 ± 5.1%) were less (P < 0.0008) than the number and percentage that completely regressed (15.0 ± 1.7; 66.8 ± 5.1%). Follicles that later recovered initially reached maximal diameter on a later day (P < 0.0001) after emergence at 2 mm (4.3 ± 0.2 d) and at a larger (P < 0.0001) diameter (5.8 ± 0.2 mm) than follicles that completely regressed (3.2 ± 0.1 d; 4.7 ± 0.1 mm). The follicle-stimulating hormone surge that stimulated wave 2 began earlier and was more sustained in a subgroup with a high percentage of recovered follicles (61%) than in a subgroup with a low percentage (24%). Recovery began on Day -1.0 ± 0.1 when the follicles had regressed to 3.7 ± 0.1 mm. Diameter of subordinate follicles on Day -6 or before the expected days of luteolysis was greater (P < 0.05) when in the corpus luteum (CL) ovary than when in the non-CL ovary. During expected luteolysis, more follicles (P < 0.008) per ovary continued to regress when ipsilateral to the CL (9.2 ± 1.1 follicles) than when contralateral (5.8 ± 1.1), and more follicles (P < 0.02) recovered from regression when contralateral to the CL (5.0 ± 0.8) than when ipsilateral (2.2 ± 0.6). The hypothesis that the CL has a local effect on the development, regression, and recovery of the subordinate follicles of wave 2 was supported.

Defective secretion of Prostaglandin F2α during development of idiopathic persistent corpus luteum in mares.

Five mares that developed idiopathic persistent corpus luteum (PCL) were compared with 5 mares with apparently normal interovulatory intervals (IOIs). Progesterone (P4) and a metabolite of prostaglandin F2α (PGFM) were assayed daily beginning on the day of ovulation (Day 0). Transition between the end of an initial progressive P4 increase and the beginning of a gradual decrease in P4 occurred on mean Day 6. The gradual decrease in P4 between Days 6 and 12 was less (approached significance, P < 0.06) in the PCL group than in the IOI group. The P4 concentration on Day 12 (before luteolysis in IOI group) was greater (P < 0.05) in the PCL group than in the IOI group. In a post hoc comparison, an interaction (P < 0.04) of group by day for Days 4 to 7 indicated that the end of the progressive increase in P4 was temporally associated with a transient increase in concentration of PGFM in IOI mares but not in PCL mares. Complete luteolysis (P4 < 1 ng/mL) occurred in the IOI mares on Days 13 to 15. Partial luteolysis (mean P4 decrease, 62%) occurred in 3 of the 5 PCL mares. Normalization to the day at the end of the most pronounced P4 decrease in the IOI mares and in the 3 PCL mares with partial luteolysis resulted in a day-by-group interaction (P < 0.05) for PGFM concentration. The interaction was partly from lower PGFM concentration on the day at the end of the pronounced P4 decrease in the 3 PCL mares than in the IOI mares. The peak of a transient PGFM increase and the day at the end of the most pronounced decrease in P4 were synchronized in each IOI mare but not in any of the 3 PCL mares. In the other 2 PCL mares, partial luteolysis did not occur, and a transient increase in PGFM was not apparent. Results tentatively indicated that the relationship between P4 and PGFM may be altered as early as Day 6 in PCL mares and supported the hypothesis that prostaglandin F2α secretion is defective in mares with idiopathic PCL.

Concentrations of progesterone, a metabolite of PGF2α, prolactin, and luteinizing hormone during development of idiopathic persistent corpus luteum in mares.

In experiment 1, daily blood samples were available from Days 0 to 20 (Day 0 = ovulation) in mares with an interovulatory interval (IOI, n = 5) and in mares that developed idiopathic persistent corpus luteum (PCL, n = 5). The PCL was confirmed by maintenance of progesterone (P4) concentration until end of the experiment (Day 20). Significant interactions of group and day revealed the novel findings that luteinizing hormone (LH) was lower (P < 0.05) in the PCL group than that in the IOI group on Days 0 to 4, and prolactin was lower (P < 0.05) on Days 1, 4, 6, and 7. In experiment 2, treatment with a gonadotropin-releasing hormone antagonist (n = 6) significantly reduced LH on Days 1 to 6 compared with the controls (n = 6) but did not support the hypothesis that low LH during the postovulatory period increases the frequency of PCL. In experiment 3, P4, PGFM (a PGF2α metabolite), and prolactin concentrations on Days 12 to 20 from 2 reported experiments were combined to increase the number of mares with an IOI (n = 11) or a PCL (n = 11). An abrupt and complete decrease in P4 (luteolysis) began on Day 13 in the IOI group compared with a gradual and partial P4 decline after Day 12 in the PCL group. Concentrations of PGFM and prolactin were lower (P < 0.05) in the PCL group than those in the IOI group on the day at the end of the most pronounced decrease in P4. The PCL mares were subgrouped into those with an abrupt but incomplete P4 decrease (partial luteolysis; n = 5) at the expected time and those without partial luteolysis (n = 6). There were no significant differences between the 2 subgroups in concentrations of PGFM and prolactin, but on a tentative basis (P < 0.10), the concentration of PGFM seemed more focused on the day of the most pronounced decrease in P4 in the subgroup with partial luteolysis. Results for PCL compared with IOI indicated (1) postovulatory LH and prolactin were lower, (2) treatment to reduce postovulatory LH did not increase the incidence, and (3) both PGFM and prolactin were lower on the day of the most pronounced decrease in P4.

Proteomic analysis of seminal plasma and sperm cells and their associations with semen freezability in Guzerat bulls.

The objective of the present study was to describe the relationship of seminal plasma and total sperm cell proteins with the semen freezability parameters of Guzerat bulls. Thirteen bulls were subjected to breeding soundness evaluation. Semen samples were collected, cryopreserved, and then post-thawing sperm kinetics were assessed, where high ( = 7) and low ( = 6) freezability groups were defined. Seminal plasma and total sperm proteins from the 2 groups were separated by 2-dimensional SDS-PAGE, and spots were identified by mass spectrometry. Semen parameters post-cryopreservation were as follows in the high and low freezability groups, respectively: mean total motility, 52.4 ± 20.5 and 13.7 ± 3.9; percentage of normal sperm, 89.0 ± 2.6 and 64.7 ± 14.0; and reactivity of hypo-osmotic swelling test, 38.9 ± 4.7 and 13.6 ± 3.7. Three seminal plasma proteins (osteopontin-K, DNase γ precursor, and DNASE1L3) and 6 proteins from sperm cells (acrosome formation-associated factor isoform 2, annexin A1, disintegrin and metalloproteinase domain-containing protein 2, dihydrolipoyl dehydrogenase, and glyceraldehyde-3-phosphate dehydrogenase) were highly expressed ( < 0.05) in the high freezability group. Another 6 seminal plasma proteins (acrosin inhibitor 1, glutathione peroxidase 3, metalloproteinase inhibitor 2, ephrin-A1, annexin A1, and platelet-activating factor acetylhydrolase) were significantly higher ( < 0.05) in the low freezability group. We described the associations of seminal plasma and sperm cell proteins with post-thawing sperm viability of Guzerat bulls raised in a typical semiarid environment. Such associations indicate that specific seminal plasma proteins more abundant in bulls of low semen freezability may be a response to an early oxidative stress that is not detected by conventional prefreezing semen evaluation. Moreover, specific sperm proteins were more associated with good freezability. The results presented here can serve as guidelines for future research aiming to develop better extenders and/or to improve bull semen selection for cryopreservation.

Stimulation of LH, FSH, and luteal blood flow by GnRH during the luteal phase in mares.

A study was performed on the effect of a single dose per mare of 0 (n = 9), 100 (n = 8), or 300 (n = 9) of GnRH on Day 10 (Day 0 = ovulation) on concentrations of LH, FSH, and progesterone (P4) and blood flow to the CL ovary. Hormone concentration and blood flow measurements were performed at hours 0 (hour of treatment), 0.25, 0.5, 1, 2, 3, 4, and 6. Blood flow was assessed by spectral Doppler ultrasonography for resistance to blood flow in an ovarian artery before entry into the CL ovary. The percentage of the CL with color Doppler signals of blood flow was estimated from videotapes of real-time color Doppler imaging by an operator who was unaware of mare identity, hour, or treatment dose. Concentrations of LH and FSH increased (P < 0.05) at hour 0.25 and decreased (P < 0.05) over hours 1 to 6; P4 concentration was not altered by treatment. Blood flow resistance decreased between hours 0 and 1, but the decrease was greater (P < 0.05) for the 100-µg dose than for the 300-µg dose. The percentage of CL with blood flow signals increased (P < 0.05) between hours 0 and 1 with no significant difference between the 100- and 300-µg doses. The results supported the hypothesis that GnRH increases LH concentration, vascular perfusion of the CL ovary, and CL blood flow during the luteal phase; however, P4 concentration was not affected.

Persistence and recovery of regressing 3-mm ovarian follicles in heifers.

The persistence and outcome of 3-mm follicles before the emergence of follicular wave 1 were studied every 6 hours in 15 heifers beginning on Day 14 (Day 0 = ovulation). A mean of 9.1 ± 1.3 persistent 3-mm follicles (P3Fs) per heifer was detected with persistence for 3.5 ± 0.1 days. The P3Fs either regressed continuously and remained in the 3-mm range (3.0-3.9 mm) or regressed but with a transient increase in diameter during regression. Some (43%) P3Fs were rescued to become growing follicles in wave 1. The number of follicles that became part of wave 1 was less (P < 0.0001) for follicles that originated from a P3F (4.2 ± 1.0 P3Fs) than for follicles that did not originate from a P3F (11.9 ± 1.6 follicles). The day of rescue of wave 1 follicles from a P3F (Day -1.1 ± 0.6) was earlier (P < 0.001) than for emergence of follicles at 3 mm that did not originate from a P3F (Day -0.5 ± 0.5). A cluster of 5.1 ± 0.6 P3Fs was identified in 10 of 15 heifers by the synchronized peaks of transient diameter increases at the 6-hour interval corresponding to Day -4.0 ± 0.3. Concentrations of FSH oscillated at 12-hour intervals with a peak (P < 0.05) 6 hours before and 6 hours after the beginning of a transient diameter increase during a P3F. Concentration of FSH was greater (P < 0.02) in heifers with a high number (11-18) of P3Fs per heifer (0.27 ± 0.02 ng/mL) than with a low number (2-9) per heifer (0.17 ± 0.008 ng/mL). Results supported the novel hypothesis that 3-mm follicles may persist for two or more days and may be rescued to become growing follicles of wave 1.

Differences between follicular waves 1 and 2 in patterns of emergence of 2-mm follicles, associated FSH surges, and ovarian vascular perfusion in heifers.

The emergence (first detection) of 2-mm follicles, FSH surges, and ovarian vascular perfusion for follicular wave 1 and surge 1 (n = 26) and wave 2 and surge 2 (n = 25) were studied daily in heifers. The day the future dominant follicle was closest to 5.5 mm was designated Day 0 for each wave. In wave 1, many 2-mm follicles (41%) emerged on Days -5 to -3, whereas FSH surge 1 did not begin until Day -3. Concentration of FSH increased abruptly in 1 day to a peak on the day of maximal number of emerging 2-mm follicles, although the day of maximal number relative to Day 0 differed among individuals. The first emergence of 2-mm follicles in wave 2 occurred concurrently with the first increase in the FSH of surge 2. In wave 1, ovarian resistance to vascular perfusion was negatively correlated (r = -0.48, P < 0.05) with a number of 2-mm follicles on Days -4 to -1 for ovaries that did not contain the preovulatory follicle; vascular perfusion increased with an increase in the number of small follicles. The following hypotheses were supported for wave 1 but not for wave 2: (1) an increase in the number of emerging 2-mm follicles of a follicular wave occurs before the beginning of an increase in FSH, (2) the day of maximal number of emerging 2-mm follicles occurs concurrently with an abrupt FSH increase on different days among individuals, and (3) the association between the number of emerging 2-mm follicles and the extent of ovarian vascular perfusion is positive.

Proteomics of endometrial fluid after dexamethasone treatment in mares susceptible to endometritis.

Corticotherapy is a common treatment in mares susceptible to endometritis. Isoflupredone improves pregnancy rates and affects the protein profile of endometrial fluid in comparison to untreated mares. Dexamethasone decreases postbreeding fluid accumulation and uterine edema; however, its effects on the protein profile of the endometrial fluid have not yet been studied. The aim of the present study was to verify the effect of dexamethasone on the protein profile of endometrial fluid, in the presence or absence of infection, from mares susceptible to persistent postbreeding endometritis. Nine susceptible mares aged between 7 and 18 years were used. After checking for signs of estrus, mares were subjected to four treatments: C: mares received no treatment and served as control; D: mares received 40-mg dexamethasone at breeding, with collection of samples after 6 hours; I-6 and I-24: intrauterine infusion of 1 × 10(9)Streptococcus zooepidemicus/mL and samples collected after 6 and 24 hours; I/D-6 and I/D-24: intrauterine infusion of 1 × 10(9)S zooepidemicus/mL and 40-mg dexamethasone, collecting the sample after 6 and 24 hours. All mares were subjected to all treatments. Samples were collected and subjected to two-dimensional electrophoresis and mass spectrometry for the identification of relevant protein spots. Corticotherapy altered the protein profile of the endometrial fluid of susceptible mares, characterized by an increase and/or decrease in the optical density of inflammatory acute-phase proteins. We conclude that the use of dexamethasone in mares with and without infection alters the protein profile of endometrial fluid of susceptible mares.

Relationships among nitric oxide metabolites and pulses of a PGF2α metabolite during and after luteolysis in mares.

Hourly circulating concentrations of a PGF2α metabolite (PGFM), progesterone (P4), and LH were obtained from a reported project, and concentrations of nitric oxide (NO) metabolites (NOMs; nitrates and nitrites) were determined in eight mares. Unlike the reported project, hormone concentrations were normalized to the peak of the first PGFM pulse of luteolysis (early luteolysis), second PGFM pulse (late luteolysis), and a pulse after luteolysis. The duration of luteolysis was 23.1 ± 1.0 hours, and the peak of the first and second PGFM pulses occurred 6.5 ± 0.9 and 14.8 ± 0.8 hours after the beginning of luteolysis. Concentration of P4 decreased progressively within and between the PGFM pulses Changes were not detected in LH concentration in association with the PGFM pulses. Concentration of NOMs was greater (P < 0.05) at the peak of the PGFM pulse during early luteolysis (88.8 ± 15.0 µg/mL) than during late luteolysis (58.8 ± 9.0 µg/mL). Concentration of NOMs began to decrease (P < 0.05) 4 hours before the peak of the PGFM pulse of early luteolysis. Concentration began to increase (P < 0.05) an hour after the peak of the PGFM pulse of late luteolysis. An NOM decrease and increase was not detected during the PGFM pulse after luteolysis. On a temporal basis, results indicated that NO either is not required for luteolysis in mares or has a role in or responds only during late luteolysis. A caveat is that the relative contribution of the CL versus other body tissues to circulating concentrations of NOMs in mares has not been determined.

Spontaneous and experimental conversion of a regressing subordinate follicle of wave 1 to the dominant follicle of wave 2 in heifers.

Examination of daily ultrasound records from a previous study indicated that spontaneous conversion of a regressing largest subordinate follicle (SF) of wave 1 (SF1) to the dominant follicle (DF) of wave 2 (DF2) occurred on Day 6 or 7 (Day 0 = ovulation) in two of 28 heifers (7%). A conversion was considered definitive on the basis of no other SFs in the same ovary as SF1, thereby avoiding error in maintaining follicle identity. Spontaneous conversion appeared to involve an FSH fluctuation. In a separate study, experimental conversion of SF1 to DF2 was studied by ultrasonic imaging every 6 hours after ablating follicles other than SF1 when DF of wave 1 was close to 11.0 mm (hour 0). Diameter of SF1 decreased (P < 0.01) between hours -6 (7.8 ± 0.3 mm) and 0 (7.6 ± 0.3 mm). A decrease of 0.1 to 0.8 mm occurred in each heifer, indicating that SF1 was in early regression at hour 0. Conversion occurred in four of 12 (33%) heifers. A diameter increase (P < 0.05) in DF2 after conversion from SF1 occurred between hours 6 and 12. An increase (P < 0.05) in FSH occurred by hour 12 with and without conversion of SF1. Concentration of FSH at each of hours 30 to 48 was greater (P < 0.05) for nonconversion than that for conversion of SF1 to DF2 and greater (P < 0.05) for conversion than that for the basal concentration in controls (n = 7). The hypothesis that a regressing SF1 can be converted to DF2 by ablating other follicles was supported.

Dairy farmer use of price risk management tools.

Volatility in milk and feed prices can adversely affect dairy farm profitability. Many risk management tools are available for use by US dairy farmers. This research uses surveys of Michigan dairy farmers to examine the extent to which price risk management tools have been used, the farm and operator characteristics that explain the use of these tools, and reasons farmers have not used these tools. A 1999 survey was used to benchmark the degree to which dairy producers had used milk and feed price risk management instruments to compare with 2011 use rates. The surveys collected information about the farm characteristics such as herd size, farmland operated, business organization, and solvency position. Farm operator characteristics collected include age, education, and experience. Dairy farmer use of both milk and feed price risk management tools increased between 1999 and 2011. In 2011, herd size was positively related to the use of milk price risk management tools, whereas farms organized as a sole proprietorship were less likely to use them. Also in 2011, herd size and land operated were positively related to feed price risk management tools, whereas operator age was negatively related. Reasons why farmers had not used price risk management tools included basis risk, cost, lack of management time, cooperative membership, and lack of understanding. Conclusions include the need for educational programming on price risk management tools and a broader exploration of dairy farm risk management programs.

Effect of corticotherapy on proteomics of endometrial fluid from mares susceptible to persistent postbreeding endometritis.

The objective was to determine the effects of corticotherapy, in the presence and absence of uterine inflammation, on proteomics of endometrial fluid from mares susceptible to endometritis. In 11 mares, estrus was induced seven times with 5 mg PGF(2α) given at 14-day intervals. The first estrus was a control (no treatment). During the third estrus, mares received glucocorticoid (GC) treatment (20 mg isoflupredone acetate) every 12 h, for three consecutive days. The fifth estrus was the Infected treatment (intrauterine infusion of 1 × 10(9) colony-forming unit/mL Streptococcus equi subspecies zooepidemicus). Finally, the seventh was a combination of GC + Infected treatment (infusion of bacteria 24 h after the first GC treatment). At 12 h after the end of each treatment, uterine samples were collected and submitted to two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) for protein separation and mass spectrometry. Both GC treatment and uterine lumen infection induced proteomic alterations in the endometrial fluid of susceptible mares, characterized by an increase, decrease, or both in the relative optic density and/or frequency of inflammatory acute phase proteins (APP), with major alterations occurring when corticotherapy was applied in the presence of an infectious process. Corticotherapy in the presence of infection increased α(1)-antitrypsin (AAT), transthyretin (TT), and actin, but reduced immunoglobulin G, whereas intrauterine infection increased haptoglobin (Hp) and apolipoprotein A-1 (ApoA-1) and decreased transferrin (TF). Infection reduced levels of α(1)-antitrypsin and transthyretin, whereas corticotherapy in the presence of infection increased their frequency. We concluded that GC influenced the immune response, not only as suppressors, but also as enhancers of local defense mechanisms, through an immunomodulatory action. Short-term corticotherapy could be beneficial for treatment of uterine infectious processes in the mare.

Effect of intensified feeding of heifer calves on growth, pubertal age, calving age, milk yield, and economics.

The objective of this study was to determine if increasing the energy and protein intake of heifer calves would affect growth rates, age at puberty, age at calving, and first lactation milk yield. A second objective was to perform an economic analysis of this feeding program using feed costs, number of nonproductive days, and milk yield data. Holstein heifer calves born at the Michigan State Dairy Cattle Teaching and Research Center were randomly assigned to 1 of 2 dietary treatments (n=40/treatment) that continued from 2 d of age until weaning at 42 d of age. The conventional diet consisted of a standard milk replacer [21.5% crude protein (CP), 21.5% fat] fed at 1.2% of body weight (BW) on a dry matter basis and starter grain (19.9% CP) to attain 0.45 kg of daily gain. The intensive diet consisted of a high-protein milk replacer (30.6% CP, 16.1% fat) fed at 2.1% of BW on a dry matter basis and starter grain (24.3% CP) to achieve 0.68 kg of daily gain. Calves were gradually weaned from milk replacer by decreasing the amount offered for 5 and 12 d before weaning for the conventional and intensive diets, respectively. All calves were completely weaned at 42 d of age and kept in hutches to monitor individual starter consumption in the early postweaning period. Starting from 8 wk of age, heifers on both treatments were fed and managed similarly for the duration of the study. Body weight and skeletal measurements were taken weekly until 8 wk of age, and once every 4 wk thereafter until calving. Calves consuming the intensive diet were heavier, taller, and wider at weaning. The difference in withers height and hip width was carried over into the early post-weaning period, but a BW difference was no longer evident by 12 wk of age. Calves fed the intensive diet were younger and lighter at the onset of puberty. Heifers fed the high-energy and protein diet were 15 d younger at conception and 14 d younger at calving than heifers fed the conventional diet. Body weight after calving, daily gain during gestation, withers height at calving, body condition score at calving, calving difficulty score, and calf BW were not different. Energy-corrected, age-uncorrected 305-d milk yield was not different, averaging 9,778 kg and 10,069 kg for heifers fed the conventional and intensive diets, respectively. However, removing genetic variation in milk using parent average values as a covariate resulted in a tendency for greater milk from heifers fed the intensive diet. Preweaning costs were higher for heifers fed the intensive diet. However, total costs measured through first lactation were not different. Intensified feeding of calves can be used to decrease age at first calving without negatively affecting milk yield or economics.