Direct and carry-over effect of grassland herbage allowance on metabolic hormones and reproduction in primiparous beef cows undergoing temporary weaning and flushing.

Grazing management significantly contributes to low beef production in cow-calf systems within the Rio de la Plata native grasslands. An herbage allowance (HA) of 4 kg DM/kg BW increased the productive response of primiparous cows grazing shallow soils compared to 2.5. However, the impact of HA on metabolic changes and its association with productive response were not studied. We studied two levels of native grassland HA from -150 days relative to calving (DC) to weaning (195 DC) in spring-calving primiparous beef cows undergoing temporary weaning (TW) and flushing at 86 ±â€¯12 DC on herbage intake (HI), body condition score (BCS), BW, milk yield, calf weight, concentrations of metabolic hormones, and the probability of ovulation and pregnancy. Thirty-one heifers were assigned to HA treatments that fluctuated throughout seasons: autumn (-150 to -90 DC) at 5 and 3 kg DM/kg BW, winter (-90 to 0 DC) at 3 and 3 kg DM/kg BW, and spring-summer (0 to 195 DC) at 4 and 2 kg DM/kg BW for High and Low HA, respectively. Data were analysed using linear models and generalised linear models for continuous and categorical variables, respectively. During the autumn period, HI, insulin, IGF-I, BCS, and BW were higher in High HA than Low, despite small differences in herbage mass between HA. Throughout the winter, spring, and summer, HI, insulin, leptin, and BCS changes did not differ between HA. However, IGF-I concentrations were greater at -65 and -40 DC (84 vs 55 ±â€¯8.6 ng/mL; P < 0.05) and tended to be greater after TW in High HA than Low. The probability of ovulation did not reach significance (0.94 vs 0.75 ±â€¯0.11 for High and Low HA, respectively; P = 0.125), while the probability of pregnancy was greater in High HA than in Low HA (0.9 vs 0.61 ±â€¯0.10; P = 0.07). Ovulation probability exhibited a positive association with IGF-I concentrations at -90 and -40 DC (P < 0.05), but not postpartum. Milk yield did not differ between treatments, while calf weight was heavier at weaning in High HA cows (194 vs 178 ±â€¯3.3 kg; P < 0.05). High HA enhances autumn HI and BCS and generates a carry-over effect on IGF-I concentrations throughout winter and after TW ("metabolic memory"), explaining the better reproductive response. Moderate changes in cows' nutrition during autumn contribute to changes in metabolic status and reproductive outcomes in primiparous cows grazing moderate herbage production native grasslands.

Convergence and divergence in mortality: A global study from 1990 to 2030.

An empirical question that has motivated demographers is whether there is convergence or divergence in mortality/longevity around the world. The epidemiological transition is the starting point for studying a global process of mortality convergence. This manuscript aims to provide an update on the concept of mortality convergence/divergence. We perform a comprehensive examination of nine different mortality indicators from a global perspective using clustering methods in the period 1990-2030. In addition, we include analyses of projections to provide insights into prospective trajectories of convergence clubs, a dimension unexplored in previous work. The results indicate that mortality convergence clubs of 194 countries by sex resemble the configuration of continents. These five clubs show a common steady upward trend in longevity indicators, accompanied by a progressive reduction in disparities between sexes and between groups of countries. Furthermore, this paper shows insights into the historical evolution of the convergence clubs in the period 1990-2020 and expands their scope to include projections of their expected future evolution in 2030.

Is a Refundable Deductible Insurance an advantage for the insured? a mathematical approach.

Most insurance policies include a deductible, so that a part of the claim is paid by the insured. In order to get full coverage of the claim, the insured has two options: purchase a Zero Deductible Insurance Policy or purchase an insurance policy with deductible together with Refundable Deductible Insurance. The objective of this paper is to analyze these two options and compare the premium paid by each. We define dif(P) as the difference between the premiums paid. This function depends on the parameters of the deductible applied, and we focus our attention on the sign of this difference and the calculation of the optimal deductible, that is, the values of the parameters of the deductible that allow us to obtain the greatest reduction in the premium.

Metabolic hormones, grazing behaviour, offspring physical distance and productive response of beef cow grazing at two herbage allowances.

Herbage allowance (HA) management during gestation-lactation cycle of cows grazing native grasslands improves pregnancy rates and calves' weaning weight records. Those improvements were associated with greater herbage mass, and better body condition score (BCS) and metabolic status of the cows, which could affect grazing and maternal behaviour, particularly when temporary suckling restriction (TSR) and flushing (FL) is applied. The objective of this study was to evaluate the effect of HA during the gestation-lactation period on cows' and calves' liveweight (LW), BCS, milk yield, insulin, IGF-1 and leptin concentrations, as well as the proportion of diurnal grazing activities (grazing, ruminating, walking and idling), and maternal behaviour from -10 to 70 days relative to TSR (day 0 = initiation of TSR at 86 ± 10 days relative to calving). Thirty-three primiparous Hereford cows were allocated to HA treatments during gestation and lactation, which annually averaged 2.5 (low = LHA) and 4 kg DM/kg LW (high = HHA). The LW and BCS of cows did not differ during -10 to 50 days but were greater in HHA than LHA at the end of the study (P < 0.05). Concentrations of IGF-1 were greater in HHA compared to LHA, while insulin and leptin did not differ. Grazing was lower in HHA than LHA, and the opposite occurred with ruminating and idling (P < 0.05). Cow-calf physical distance was greater in LHA cows compared to HHA (P < 0.05) and increased greatly in the former group after FL, while this increase was lower and later in HHA cows. Milk yield was greater in HHA (P < 0.05), and calves' weight did not differ between treatments from day -10 to 35, but was greater in HHA compared to LHA from 45 days until the end of the study. Thus, the HHA in a low herbage height and mass condition resulted in greater IGF-1 concentrations and milk yield, and induced changes in grazing and maternal behaviour that were associated with increased cows' LW, BCS and calves' weight at the end of the study.

Short-term dietary protein supplementation improves reproductive performance of estrous-synchronized ewes when there are long intervals of prostaglandin or progesterone-based treatments for timed AI.

To evaluate the reproductive effects of a short-term dietary protein supplementation (Days -10 to -3) before timed AI (TAI = Day 0), 471 Merino ewes grazing native pastures were estrous-synchronized when there were either long intervals between prostaglandin administrations (two prostaglandin injections 15 or 16 d apart; PG15 and PG16, respectively) or with a progesterone-eCG (P4-eCG) protocol, resulting in a 3 × 2 experimental design. Ovulation rate on Day 8 (OR), non-estrous-return to Day 21 (NRR21), and fertility, prolificacy and fecundity on Day 70 were evaluated. The interaction between estrous synchronization protocol and supplementation was not significant for any of these variables (P > 0.05). Supplementation increased OR, prolificacy and fecundity (+0.14, +0.15 and +0.14, respectively, P < 0.01), but did not affect NRR21 or fertility of ewes (+6.2% and +6.7% respectively, P > 0.05). Ewes treated using the PG15 and PG16 protocols had a lesser OR (-0.27), prolificacy (-0.22) and fecundity (-0.20) than ewes treated using P4-eCG protocol (P < 0.01 for each), and similar NRR21 and fertility (-5.4% and -7.9% respectively, P > 0.05 for both variables), without significant differences between the PG15 and PG16 groups. In conclusion, a short-term dietary protein supplementation before TAI improved OR, prolificacy and fecundity of ewes which were estrous-synchronized by imposing long interval PG (15 or 16 d apart) or P4-eCG-based protocols. There was a greater OR, prolificacy and fecundity when there was use of the P4-eCG compared to long interval PG-based protocols. Estrous-non-return rate after AI and fertility as a result TAI were not affected by either the supplementation or the estrous synchronization protocols used.

[Efficacy of topical povidone-iodine applied the day before cataract surgery to reduce conjunctival flora]. / Eficacia de la povidona yodada tópica administrada el día previo a la cirugía de catarata para reducir la flora conjuntival.

OBJECTIVE: To evaluate the efficacy of the topical use of periocular and conjunctival povidone-iodine solution applied the day before cataract surgery to reduce conjunctival flora. PATIENTS AND METHODS: Randomized and prospective clinical trial with 82 patients. The treatment group (41 patients) received an application of topical 10% povidone-iodine solution on the periocular skin and instillation of topical 5% povidone-iodine solution on the forniceal conjunctiva the day before and one hour before surgery. The control group (41 patients) only received the usual perioperative disinfectant. Conjunctival smears were obtained from in all patients at the end of the surgery and these were sent to the Microbiology Laboratory for culture. RESULTS: In the treatment group 1 positive culture was found in the 41 eyes (2.4%). In the control group, there were positive cultures in 6 out of 41 eyes (14.6%). The difference is statistically significant (p<0.05). CONCLUSIONS: The disinfecting of the periocular skin with 10% povidone-iodine solution and of the conjunctiva with 5% povidone-iodine solution the day before and one hour before cataract surgery is effective in reducing conjunctival bacterial colonization compared with perioperative disinfection alone.

Blue filter amblyopia treatment protocol for strabismic amblyopia: a prospective comparative study of 50 cases.

PURPOSE: Previous studies of monochromatic visual evoked potentials confirm the strong suppression of (the cortical representation of) paracentral retinal areas of functionally amblyopic eyes, by a flat response to a blue stimulus. A clinical trial stimulating these areas with blue light was encouraging, and justified a prospective comparison of this treatment with conventional classic treatment. SUBJECTS AND METHODS: In 50 strabismic children with amblyopia, the blue filter treatment protocol (flash stimulation with, and the wearing of, a blue filter during occlusion of the better eye for one hour daily) was compared with the classical treatment (full time total occlusion by patch) in a prospective matched and randomized study. Patients 3 to 7 years old without previous treatment and a visual acuity up to 0.3 were admitted to the study. Visual acuity and fixation behavior were used as the parameters of comparison. Visual Evoked Potentials by monochromatic flashes were also studied. Results of treatment were compared after 6 months. RESULTS: The visual acuity outcome for the blue filter treatment was "statistically significantly" better (p=0.005). The greatest improvement was seen in the subgroup of children with eccentric fixation (p=0.01). Fixation behavior also showed a better outcome from the blue filter treatment (p=0.05) favoring especially children between 3 and 5 years. In children of this age with a visual acuity better than 0.1 we found a very "statistically significant" difference between the two treatments (p=0.004). In children 3 to 5 years old with poorer visual acuity we also found a "statistically significant" difference in the two treatments (p=0.04). The interocular difference of amplitude on the Visual Evoked Potentials also demonstrated more improvement in children treated with the blue filter. This treatment improved especially the cortical response to blue flash stimulation, correlating to paracentral retinal areas. CONCLUSIONS: The blue filter treatment protocol provided better results for treating amblyopia than the conventional classic occlusion treatment method. We propose that stimulation of these paracentral retinal areas triggers a better disinhibition of a functionally amblyopic eye.