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Milk coagulation properties (MCP) have been widely investigated in the past using milk collected from different cattle breeds and herds. However, to our knowledge, no previous studies have assessed MCP in individual milk samples from several multi-breed herds characterized by either high or low milk productivity, thereby allowing the effects of herd and cow breed to be evaluated independently. Multi-breed herds (n = 41) were classified into 2 categories based on milk productivity (high vs. low), defined according to the average milk net energy yielded daily by lactating cows. Milk samples were taken from 1,508 cows of 6 different breeds: 3 specialized dairy (Holstein-Friesian, Brown Swiss, Jersey) and 3 dual-purpose (Simmental, Rendena, Alpine Grey) breeds, and analyzed in duplicate (3,016 tests) using 2 lactodynamographs to obtain 240 curd firming (CF) measurements over 60 min (1 every 15 s) for each duplicate. The 5 traditional single-point MCP (RCT, k20, a30, a45, and a60) were yielded directly by the instrument from the available CF measures. All 240 CF measures of each replicate were also used to estimate 4 individual equation parameters: RCT estimated according to curd firm change over time modeling (RCTeq), asymptotic potential curd firmness (CFP), curd firming instant rate constant (kCF), and syneresis instant rate constant (kSR) and 2 derived traits: maximum curd firmness achieved within 45 min (CFmax) and time at achievement of CFmax (tmax) by curvilinear regression using a nonlinear procedure. Results showed that the effect of herd-date on traditional and modeled MCP was modest, ranging from 6.1% of total variance for k20 to 10.7% for RCT, whereas individual animal variance was the highest, ranging from 32.0% for tmax to 82.5% for RCTeq. The repeatability of MCP was high (>80%) for all traits except those associated with the last part of the lactodynamographic curve (i.e., a60, kSR, kCF, and tmax: 57 to 71%). Reproducibility, taking into account the effect of instrument, was equal to or slightly lower than repeatability. Milk samples collected in farms characterized by high productivity exhibited delayed coagulation (RCTeq: 18.6 vs. 16.3 min) but greater potential curd firmness (CFP: 76.8 vs. 71.9 mm) compared with milk samples collected from lowproductivity herds. Parity and days in milk influenced almost all MCP. Large differences in all MCP traits were observed among breeds, both between specialized and dual-purpose breeds and within these 2 groups of breeds, even after adjusting for milk quality and yield. Milk quality and MCP of samples from Jersey cows, and coagulation time of samples from Rendena cows were better than in milk from Holstein-Friesian cows, and intermediate results were found with the other breeds of Alpine origin. The results of this study, taking into account the intrinsic limitation of this technique, show that the effects of breed on traditional and modeled MCP are much greater than the effects of herd productivity class, parity, and DIM. Moreover, the variance in individual animals is much greater than the variance in individual herds within herd productivity class. It seems that improvement in MCP depends more on genetics (e.g., breed, selection) than on environmental and management factors. [ABSTRACT FROM AUTHOR]

In the dry Mahafaly region of southwestern Madagascar, livestock keeping plays a key role in people's livelihoods. Especially zebu cattle and goats are socially important and contribute considerably to regular income of local households. We therefore analyzed the reproductive performance of local breeds along with livestock owners' culling strategies to determine herd dynamics, opportunities for economic development, as well as potential improvements, by using a combined methodical, both production-oriented and economic approach. Data was collected through interviews on the progeny history of breeding females (506 cows and 593 does) and their offspring (721 calves and 1073 kids). Based on the results, reproduction parameters were calculated and entered into the PRY Herd Life model to simulate herd development for present management ( status quo ) and two alternate scenarios assuming either (i) improved feeding and resulting higher productivity of breeding females or (ii) improved culling. Based on prices collected at local markets, a Monte Carlo simulation was used to estimate annual costs and revenues from livestock keeping. Age at first parturition was 40.5 ± 11.2 months for cattle and 21.3 ± 9.8 months for goats. Females from both species showed long parturition intervals (cattle 24.2 ± 8.7 months, goats 12.4 ± 5.7 months) whereas reported offspring mortality was low with 2.5% of cattle and 18.8% of goats dying before reaching maturity. On the other hand, market prices, especially for zebus, were quite high, leading to annual contribution margins of 33 € per cattle unit and 11 € per goat unit. The simulations indicated that improved feeding could support substantial herd expansion and productive offtake rates, whereas improved culling would stabilize livestock numbers and concomitantly increase monetary herd output. Even though the current livestock husbandry system appears profitable, it might reach its limits in the near future due to the region's restricted ecological carrying capacity. Increasing livestock offtake would allow livestock keepers to raise their economic benefit without compromising herd development or enhancing the pressure on pasture resources. [ABSTRACT FROM AUTHOR]

• Second litter syndrome can be evaluated with total born and born alive piglets. • A total of 56.63% of sows did not improve born alive piglets in second parity. • Within herds, a mean of 57.75% of sows showed second litter syndrome. • Second litter syndrome is even shown in farms with high performance. • Incidence can be reduced through first farrowing age and lactation length. Second litter syndrome (SLS) consists of a loss of prolificacy in the second parity (P2), when a sow presents the same or lower results for litter size than in the first parity (P1). This syndrome has been reported for modern prolific breeds but has not been studied for rustic breeds. The objectives of this study are to determine how and to what degree Iberian sows (a low productivity breed recently raised on intensive farms) are affected by SLS; to establish a target and reference levels; and to assess the factors influencing the performance. Analysed data correspond to 66 Spanish farms with a total of 126 140 Iberian sows. The average Iberian sow prolificacy in P1 was 8.91 total born (TB) and 8.47 born alive (BA) piglets, whereas in P2, it decreased by −0.05 TB and −0.01 BA piglets, suggesting some general incidence of SLS. At the sow level, 56.63% did not improve prolificacy in terms of BA piglets in P2, and 16.98% had a clear decrease in prolificacy, losing ≥3 BA piglets in P2. Within herds, a mean of 57.75% of sows showed SLS, with an evident decrease in the number of BA piglets in P2. The plausible target for the Iberian farm's prolificacy comes from the quartile of farms with the lowest percentage of SLS sows within the farms with the highest prolificacy between P1 and P2 (mean of 8.77 BA). So, in this subset of farms (N = 17), 47.3% of sows improved their prolificacy in P2 (i.e. did not show SLS). Hence, half the sows could be expected to show SLS even on farms with a good performance. Finally, this study brings out the main factors reducing P2 prolificacy through SLS in the Iberian breed: later age at first farrowing, long first lactation length, medium weaning to conception interval and large litter size in P1. In conclusion, improving the reproductive performance of Iberian farms requires reducing the percentage of sows with SLS, paying special attention to those risk factors. The knowledge derived from this study can provide references for comparing and establishing objectives of performance on Iberian sow farms which can be used for other robust breeds. [ABSTRACT FROM AUTHOR]

Abstract: The objectives of this study were to assess the occurrence of decreased numbers of pigs born alive (PBA) in parity 2 (D-PBA) and to evaluate the importance of D-PBA sows and herds by analyzing against using the summed numbers of PBA in parity 1 and 2 (SPBA) and nonproductive sow days (NPD). The study assessed annual data from 2001 to 2005 from 106 herds, and sow data including 137,360 farrowing records of 68,680 sows farrowed in parity 1 and 2. D-PBA was defined as the same or fewer numbers of PBA in parity 2 than that in parity 1 at either the sow or herd level. Sows or herds were categorized into two groups: D-PBA or increased PBA in parity 2 (I-PBA). NPD was defined as the number of days that sows were neither gestating nor lactating in parity 1. Mixed-effects models were used to compare the reproductive performance between the two groups. Of the 68,680 sows, 49.5% had an occurrence of D-PBA. D-PBA sows had 0.3 pigs fewer SPBA than I-PBA sows, but those sows had 1.9days shorter NPD in parity 1 than I-PBA sows (P <0.05). Over the five years studied the average annual proportion of D-PBA herds was 16%. No differences were found between the D-PBA and I-PBA herds in the number of pigs weaned per mated female per year (PWMFY), SPBA or NPD in any year. Additionally, the PWMFY was not correlated in any years with either the proportions of D-PBA sows or the difference in PBA between parity 1 and 2. In conclusion, the occurrence of D-PBA does not appear to be a serious problem in Japanese swine herds studied. [Copyright &y& Elsevier]

Abstract: The objectives of this study were to characterize sows having high lifetime efficiency and high longevity (HE–HL), to examine the relationship between lifetime measurements, and to determine the association between the sows and herd productivity. This study was conducted by obtaining sow data with 66,262 parity records of 13,786 sows born during 1999 and herd data with mean measurements of 4-year records from 2000 to 2003 in 92 herds. Sow lifetime efficiency was defined as the sum of pigs born alive in lifetime divided by the sow life days and multiplied by 365 days. Sows were categorized into three sow groups based on the upper 25 percentile of the lifetime efficiency and parity at culling ≥6. The three groups were sows having 1) the upper 25 percentile of the lifetime efficiency and parity at culling ≥6 (HE–HL sows), 2) less than the upper 25 percentile of the lifetime efficiency and parity at culling ≥6 (OE–HL sows), and 3) parity at culling ≤5 regardless of lifetime efficiency (LL sows). Mixed-effects models were used to compare reproductive performance between the three sow groups and to identify factors associated with a proportion of a HE–HL sow in the herd. Correlation analyses were done between lifetime performances in sows and between herd productivity measurements and the proportions of three sow groups in the herd. The proportions of HE–HL, OE–HL, and LL sows in 13,786 sows were 21.8%, 24.5%, and 53.7%, respectively. Lifetime efficiency was correlated with parity at culling (r =0.76; P <0.01) and nonproductive days per parity (r =−0.46; P <0.01). From first parity to the end, HE–HL sows had the greatest numbers of pigs born alive, the highest farrowing percentage, and the shortest nonproductive days per parity (P <0.01). Sows aged between 186 and 227 days at first mating were 1.09 to 1.11 times as more likely to become a HE–HL sow as those aged between 249 and 269 days at first mating (P <0.05). Of the 92 herds, mean proportion of HE–HL sows was 23.5%, and the proportions ranged from 0 to 57.6%. A higher proportion of HE–HL sows and a lower proportion of LL sows in the herd were correlated with more pigs weaned per mated female per year (P <0.01). In conclusion, HE–HL sows had high efficiency from the first parity to the end, which was attributed to herd productivity. [Copyright &y& Elsevier]