Agricultural education and research in New Zealand

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The Presidential address provides an opportunity for the president of organizations such as ours to express publicly his ideas and opinions on any matter with somewhat more weight than they might otherwise carry. This privilege must therefore be taken with due humility and circumspection, for it is not unusual for statements to be weighed solely on the standing of the person making them, without reference to his special qualifications for doing so; nor, unfortunately, is it rare for people well qualified in certain spheres to make seemingly authoritative statements on things about which they know very little.     

Vaginal prolapse in sheep—Part IV: Cyclic changes in the vulva,vestibule, and vagina during the year

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Many English breeds of sheep exhibit a well-defined breeding season which begins in the autumn about February–March in the southern hemisphere and ends about July–August. Over this period, the oestrous cycle, in unmated ewes, is repeated at intervals averaging 16 to 17 days. At other times of the year, these breeds are in anoestrum during which the 'ovaries and the tubular parts of the reproductive system are relatively quiescent.     

The Effect of Piglet Expulsion in the Sow on Plasma Cortisol, Adrenocorticotropic Hormone and β-endorphin

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Previous studies have shown an increase in plasma cortisol in gilts over farrowing irrespective of environment suggesting that factor(s) associated with parturition itself cause physiological stress. Factors involved in mediating the hypathalomo–pituitary–adrenal (HPA) axis at parturition are not well understood. This study examines the effect of piglet expulsion on the pituitary–adrenal axis by measurement of plasma cortisol, adrenocorticotropic hormone (ACTH) and β-endorphin. The effect of farrowing environment in modulating the acute response to piglet expulsion is also investigated. Twelve second parity sows, with indwelling jugular catheters, were moved into either a farrowing crate or a straw-bedded pen 5 days before their expected parturition date (EPD). Blood samples were taken from each sow during a prefarrowing baseline period and then rapid samples (2.5 mins) were taken for 10 min following the birth of two piglets. No effect of environment was found on any of the hormonal variables which reinforces the hypothesis that the physiological stress seen in parturient pigs is due to some intrinsic factor of parturition. Plasma cortisol, ACTH and β-endorphin did not change significantly in the period following piglet expulsion suggesting that individual piglet expulsions do not play a major role in 'parturition stress'. There was however, an increase in plasma cortisol, ACTH and β-endorphin in response to increasing piglet number which is consistent with previous studies of general farrowing in which cortisol increased as farrowing progressed. Therefore this study reinforces the hypothesis that physiological stress increases with ongoing parturition although this does not appear to be a result of piglet expulsion. The potential role of other factors which may be involved in causing 'parturition stress' should be investigated.     

Assessing Environmental Influences on Solvent Retention Capacities of Two Soft White Spring Wheat Cultivars

The solvent retention capacity test (SRC) (AACC Approved Method 56‐11) of flour is used to evaluate multiple aspects of wheat (Triticum aestivum L.) quality including pentosan content, starch damage, gluten strength, and general water retention based on the ability of flour to retain a range of solvents. The objectives of this study were to evaluate the effects of grain production environment in general and crop irrigation and fertility management in particular on SRC of soft wheat flour, and to evaluate the ability of SRC to predict end‐use quality across diverse environments. Two soft white spring wheat cultivars ‘Pomerelle’ and ‘Centennial’ were produced in a range of irrigated and rain‐fed production environments. SRC profiles and milling and baking quality parameters were measured. In a two‐year study at Aberdeen, ID, with two late‐season irrigation management regimes and two crop nitrogen fertility treatments, only wheat genotype significantly affected flour SRC. In two‐year studies at Tetonia, ID, one conducted under rain‐fed conditions and the other under irrigation, additional fertilizer applied at anthesis did not affect SRC. Correlations among quality parameters were determined using the Aberdeen and Tetonia flour samples, as well as samples of the same genotypes grown in fertility trials under rain‐fed conditions at Havre and Bozeman, MT, and under irrigation at Bozeman. Patterns of correlations among SRC values were similar for both genotypes. Grain test weight was negatively correlated with sodium carbonate and sucrose SRC of both genotypes. Flour protein was strongly positively correlated with sucrose and lactic acid SRC of both genotypes. The optimal regression models for predicting sugar snap cookie diameter (AACC Approved Method 10‐52) as a function of protein, SRC, flour extraction, and kernel hardness were different for the two cultivars. SRC evaluations of flours from these trials were consistent with large genotype and environment effects, yet minimal genotype × environment interaction. This suggests that selection among genotypes within an environment will produce a gain‐from‐selection observable in multiple and diverse environments.     

Effect of Progesterone and Ionomycin on Domestic Cat Sperm Motility Patterns and Acrosome Reaction

This study was aimed at assessing the changes in sperm motion patterns and the percentage of acrosome reaction (AR) in domestic cat semen after treatment with either ionomycin or progesterone (P₄). Ten ejaculates were collected from five tomcats using an artificial vagina, and were diluted, centrifuged and resuspended in a capacitation medium. Samples were evaluated and divided into seven equal aliquots and, after 2 h at 25°C, were incubated for 30 min at 38°C in 5% CO₂ and then analyzed. Computer-assisted sperm analysis and a combination of three fluorescent probes were used to assess sperm plasma, acrosomal membrane integrity and mitochondrial transmembrane potential. Thirty minutes after the start of incubation, P₄ was added (10 μg/ml) to the P1 group. Groups P2 and P3 were supplemented with P₄ (10 and 20 μg/ml, respectively) only after 2 h of incubation, and groups I1 and I2 were supplemented with ionomycin (4 and 8 μ m , respectively) 2 h after incubation. Group E was supplemented with ethanol (0.6%) at 2 h after incubation and group C received no supplementation. Ionomycin and P₄ treatments led to a hyperactivation-like sperm motion and an increase (p < 0.05) in the percentage of AR. Although a higher (p < 0.05) percentage of AR was obtained in group I2 when compared with all P₄ groups, a decrease (p < 0.05) in total and progressive motility was observed in I2 group. As I1 group was similar to I2 to induce AR without diminishing sperm motility, we can conclude that ionomycin at 4 μ m seems to be more suitable to trigger AR in domestic cat sperm.     

Measuring compression wood severity in spruce

As the severity of compression wood influences the mechanical and chemical properties of wood it is desirable to be able to measure compression wood severity. However, so far no satisfactory method has been reported in the literature. Here we describe how scanning FTIR micro-spectroscopy can be employed to achieve CW severity measurements on increment cores of Norway spruce (Picea abies (L. Karst.) and Sitka spruce (Picea sitchensis (Bong.) Carrière). Radial wood strips were converted into sawdust by a process that maintained their spatial orientation. Samples prepared in this way were scanned with an FTIR-microscope in reflective mode and from the spectra obtained a CW-indicator was calculated representing aromatic and carboxyl signals. This FTIR CW-indicator correlated well with alternative CW identification techniques (namely microfibril angle, transmitted light and immunolabelling of beta 1–4 galactan), which have been used to validate the method. Repeatability of the measurements was good and no systematic difference between spruce species was found. The achievable resolution of the measurements was of sub-mm order. The CW indicator described offers the opportunity to correlate CW severity with mechanical wood properties in spruce.     

Ethical equitation: Capping the price horses pay for human glory

Ethical equitation is nowadays coming into sharp focus in equestrian culture. Concerns surround the ethics of sports based on controlling an animal's locomotory responses and in using animals such as horses in sport in general. Anthropomorphically labeled misinterpretations of the responses of trained horses, such as the use of terms like “mad,” “lazy,” “keen,” and “stubborn,” may be detrimental to optimal equine welfare. Similarly, the concept of the “equine athlete” may imply an ill-informed teleological explanation of the motives of the horse in sport. Despite problems in identifying the happy horse, rewarding optimal welfare and the absence of critical stress responses in performance horses is an important step forward.Horse racing is the source of many welfare concerns because of the use of the whip and the physical dangers to horses involved in hurdle racing and steeplechasing. The use of the whip in racing is controversial and, because it does not always lead to acceleration, problematic. There is a pressing need for learning theory to be adopted in all equestrian pursuits, because such an approach would obviate the need for whips, punishment, and the use of fear in escape learning. In other disciplines, practices such as hyperflexion and soring have a significant potential to compromise the welfare of the horse in sport.The future of horse sports should involve abandoning the mandatory use of primitive control devices, such as curb bits, that have a real potential to cause harm. International governing bodies and national equestrian federations ought to proceed with removing any requirements to use curb bits and judges should reward riders who use the most humane control devices at the higher levels of competition.Finally, horse breeding should also be scrutinized under an ethical spotlight. Selecting horses on the basis of temperament has inherent risks, including lowered motivation of riders and trainers to refine their training skill set, which may also lead to significant wastage. Pure breeding risks the health and welfare of horses owing to increases in homozygous deleterious genes expressing themselves.