Effects of cottonseed cake-based diets supplemented with blood meal, alone or with lysine, on the growth of pigs

An experiment was carried out to establish the effect on the growth of pigs of including blood meal or lysine in diets containing gossypol from cottenseed cake. Forty Landrace x Large White pigs (20 of each sex) were randomly allocated to 5 treatments of 8 pigs each in a 2x2 factorial design with two levels of lysine or two levels of blood meal in the diets plus a control diet. The pigs were fed different diets and slaughtered at 75.0+/-2.0 kg live weight for carcase analysis. Supplementing the diets with blood meal resulted in higher live weight gains (p<0.001) and improved feed conversion ratios (p<0.001) than supplementing with lysine. Pigs fed the higher level of cottonseed cake showed a significant (p<0.001) depression in live weight gain and feed conversion ratio compared to those fed a low level of the cake. There was no significant difference (p>0.05) in intake in the pigs fed diets with cottonseed cake including blood meal or synthetic lysine. The kidney and liver weights of the pigs fed the diets with a higher level of cottonseed cake were significantly greater (p<0.001) than in those fed the lower level, but when the diets containing cottonseed cake were supplemented with blood meal or lysine at the same level there was no significant difference (p>0.05) in the weights of these organs. Lysine or other factors derived from blood meal appear to be more efficient than synthetic lysine in reducing the adverse effects of gossypol.

An evaluation of the use of Cottonseed cake in the diet of growing pigs

An experiment was conducted to determine the effects of including cottonseed cake in rations for weaned growing pigs. Thirty-two Landrace x Large White pigs, weighing 20-24 kg, were included in four blocks formed on the basis of initial weight within sex in an otherwise completely randomized block design. The pigs were killed when they reached a live weight of 75.0 +/- 2.0 kg and the half careases were analysed into cuts and the weights of the organs were recorded. An estimate of the productivity of the pigs on each diet was calculated. Cottonseed cake reduced the voluntary feed intake (p < 0.001) and live weight gains (p < 0.001) and increased the heart, kidney and liver weights (p < 0.01). The pigs on the soya bean-based control diet took the shortest time to reach slaughter weight. The result was probably in part due to lysine deficiency and in part to the effect of free gossypol. It was found that it is at present cost-effective to include cottonseed cake in pig weaner grower diets up to 300 g/kg in Cameroon.

Prediction of cottonseed longevity

The objective of this work was to determine the viability equation constants for cottonseed and to detect the occurrence and depletion of hardseededness. Three seedlots of Brazilian cultivars IAC-19 and IAC-20 were tested, using 12 moisture content levels, ranging from 2.2 to 21.7% and three storage temperatures, 40, 50 and 65 degrees C. Seed moisture content level was reached from the initial value (around 8.8%) either by rehydration, in a closed container, or by drying in desiccators containing silica gel, both at 20 degrees C. Twelve seed subsamples for each moisture content/temperature treatment were sealed in laminated aluminium-foil packets and stored in incubators at those temperatures, until complete survival curves were obtained. Seed equilibrium relative humidity was recorded. Hardseededness was detected at moisture content levels below 6% and its releasing was achieved either naturally, during storage period, or artificially through seed coat removal. The viability equation quantified the response of seed longevity to storage environment well with K-E = 9.240, C-W = 5.190, C-H = 0.03965 and C-Q = 0.000426. The lower limit estimated for application of this equation at 65 degrees C was 3.6% moisture content.

Simulation of milk production by dairy cows fed sugarcane top-based diets with locally available supplements under Indian conditions

A model of sugarcane digestion was applied to indicate the suitability of various locally available supplements for enhancing milk production of Indian crossbred dairy cattle. Milk production was calculated according to simulated energy, lipogenic, glucogenic and aminogenic substrate availability. The model identified the most limiting substrate for milk production from different sugarcane-based diets. For sugarcane tops/urea fed alone, milk production was most limited by amino acid followed by long chain fatty acid availability. Among the protein-rich oil cake supplements at 100, 200 and 300 g supplement/kg total DM, cottonseed oil cake proved superior with a milk yield of 5.5, 7.3 and 8.3 kg/day, respectively. This was followed by mustard oil cake with 5.1, 6.5 and 7.6 kg/day, respectively. In the case of a protein-rich supplement (fish meal), milk yield was limited to 6.6 kg/day due to a shortage of long chain fatty acids. However, at 300 g of supplementation, energy became limiting, with a milk yield of 6.7 kg/day. Supplementation with rice bran and rice polishings at 100, 200 and 300 g restricted milk yield to 4.3, 4.9 and 5.5 and 4.5, 5.3 and 6.1 kg/day, respectively, and amino acids became the factor limiting milk production. The diet comprising basal sugarcane tops supplemented by leguminous fodder, dry fodder (e.g. rice or wheat straw) and concentrates at levels of 100, 200 and 300 g supplements/kg total diet DM proved to be the most balanced with a milk yield of 5.1, 6.7 and 9.0 kg/day, respectively.

Developmental programming: Deficits in reproductive hormone dynamics and ovulatory outcomes in prenatal, testosterone-treated sheep

Prenatal testosterone excess leads to neuroendocrine, ovarian, and metabolic disruptions, culminating in reproductive phenotypes mimicking that of women with polycystic ovary syndrome (PCOS). The objective of this study was to determine the consequences of prenatal testosterone treatment on periovulatory hormonal dynamics and ovulatory outcomes. To generate prenatal testosterone-treated females, pregnant sheep were injected intramuscularly (days 30-90 of gestation, term = 147 days) with 100 mg of testosterone-propionate in cottonseed oil semi-weekly. Female offspring born to untreated control females and prenatal testosterone-treated females were then studied during their first two breeding seasons. Sheep were given two injections of prostaglandin F-2alpha 11 days apart, and blood samples were collected at 2-h intervals for 120 h, 10-min intervals for 8 h during the luteal phase (first breeding season only), and daily for an additional 15 days to characterize changes in reproductive hormonal dynamics. During the first breeding season, prenatal testosterone-treated females manifested disruptions in the timing and magnitude of primary gonadotropin surges, luteal defects, and reduced responsiveness to progesterone negative feedback. Disruptions in the periovulatory sequence of events during the second breeding season included: 1) delayed but increased preovulatory estradiol rise, 2) delayed and severely reduced primary gonadotropin surge in prenatal testosterone-treated females having an LH surge, 3) tendency for an amplified secondary FSH surge and a shift in the relative balance of FSH regulatory proteins, and 4) luteal responses that ranged from normal to anovulatory. These outcomes are likely to be of relevance to developmental origin of infertility disorders and suggest that differences in fetal exposure or fetal susceptibility to testosterone may account for the variability in reproductive phenotypes.

Transgenic soya beans: economic implications for EU livestock sector

World oilseed trade consists of many closely substitutable commodities, with canola and cottonseed as possible alternatives to soya beans for many purposes. Transgenic events in all three crops have been widely adopted, particularly in North and South America, for compelling economic or agronomic reasons. Despite the close attention from organizations concerned about the potential consequences of transgenic crop adoption, there appears to be no substantiated evidence of transgenic DNA in meat or milk products when such crops are fed to livestock. The global area of these transgenic crops continues to increase. No transgenic canola, cotton or soya bean crops are permitted for commercial cultivation in Europe, and although transgenic feed resources are permitted for import, importers risk shipments being denied entry if the traces of an unauthorized transgenic crop are detected. These tight controls can mean that livestock farmers in the EU are disadvantaged due to restricted access to cheaper feed or higher feed costs, and they are thus loosing a degree of competitive advantage. This paper reviews the extent to which transgenic soya beans have become the ‘conventional’ method of cultivation elsewhere, and notes implications this has for livestock nutrition, traceability and economics within the EU. The paper concludes with discussion regarding the implications for the EU of delayed acceptance of newly available transgenic traits.